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Merge branch 'ijg' into dev

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- Restore GIF read/compressed GIF write support from jpeg-6a and
  jpeg-9d.
- Integrate jpegtran -wipe and -drop options from jpeg-9a and jpeg-9d.
- Integrate jpegtran -crop extension (for expanding the image size) from
  jpeg-9a and jpeg-9d.
- Integrate other minor code tweaks from jpeg-9*
This commit is contained in:
DRC
2020-10-27 13:28:56 -05:00
parent 7e4eac7021 9fc018fd1a
commit 88ae60986e
19 changed files with 1999 additions and 228 deletions
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8
ChangeLog.md
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@@ -101,6 +101,14 @@ TurboJPEG API libraries. This facilitates using libjpeg-turbo with CMake's
target_link_libraries(turbojpeg_program_static PUBLIC
libjpeg-turbo::turbojpeg-static)
11. Since the Unisys LZW patent has long expired, cjpeg and djpeg can now
read/write both LZW-compressed and uncompressed GIF files (feature ported from
jpeg-6a and jpeg-9d.)
12. jpegtran now includes the `-wipe` and `-drop` options from jpeg-9a and
jpeg-9d, as well as the ability to expand the image size using the `-crop`
option. Refer to jpegtran.1 or usage.txt for more details.
2.0.6
=====

15
README.ijg
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@@ -128,7 +128,7 @@ with respect to this software, its quality, accuracy, merchantability, or
fitness for a particular purpose. This software is provided "AS IS", and you,
its user, assume the entire risk as to its quality and accuracy.
This software is copyright (C) 1991-2016, Thomas G. Lane, Guido Vollbeding.
This software is copyright (C) 1991-2020, Thomas G. Lane, Guido Vollbeding.
All Rights Reserved except as specified below.
Permission is hereby granted to use, copy, modify, and distribute this
@@ -159,19 +159,6 @@ commercial products, provided that all warranty or liability claims are
assumed by the product vendor.
The IJG distribution formerly included code to read and write GIF files.
To avoid entanglement with the Unisys LZW patent (now expired), GIF reading
support has been removed altogether, and the GIF writer has been simplified
to produce "uncompressed GIFs". This technique does not use the LZW
algorithm; the resulting GIF files are larger than usual, but are readable
by all standard GIF decoders.
We are required to state that
"The Graphics Interchange Format(c) is the Copyright property of
CompuServe Incorporated. GIF(sm) is a Service Mark property of
CompuServe Incorporated."
REFERENCES
==========

6
cderror.h
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@@ -42,7 +42,7 @@ JMESSAGE(JMSG_FIRSTADDONCODE = 1000, NULL) /* Must be first entry! */
#ifdef BMP_SUPPORTED
JMESSAGE(JERR_BMP_BADCMAP, "Unsupported BMP colormap format")
JMESSAGE(JERR_BMP_BADDEPTH, "Only 8- and 24-bit BMP files are supported")
JMESSAGE(JERR_BMP_BADDEPTH, "Only 8-, 24-, and 32-bit BMP files are supported")
JMESSAGE(JERR_BMP_BADHEADER, "Invalid BMP file: bad header length")
JMESSAGE(JERR_BMP_BADPLANES, "Invalid BMP file: biPlanes not equal to 1")
JMESSAGE(JERR_BMP_COLORSPACE, "BMP output must be grayscale or RGB")
@@ -50,9 +50,9 @@ JMESSAGE(JERR_BMP_COMPRESSED, "Sorry, compressed BMPs not yet supported")
JMESSAGE(JERR_BMP_EMPTY, "Empty BMP image")
JMESSAGE(JERR_BMP_NOT, "Not a BMP file - does not start with BM")
JMESSAGE(JERR_BMP_OUTOFRANGE, "Numeric value out of range in BMP file")
JMESSAGE(JTRC_BMP, "%ux%u 24-bit BMP image")
JMESSAGE(JTRC_BMP, "%ux%u %d-bit BMP image")
JMESSAGE(JTRC_BMP_MAPPED, "%ux%u 8-bit colormapped BMP image")
JMESSAGE(JTRC_BMP_OS2, "%ux%u 24-bit OS2 BMP image")
JMESSAGE(JTRC_BMP_OS2, "%ux%u %d-bit OS2 BMP image")
JMESSAGE(JTRC_BMP_OS2_MAPPED, "%ux%u 8-bit colormapped OS2 BMP image")
#endif /* BMP_SUPPORTED */

3
cdjpeg.h
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@@ -3,6 +3,7 @@
*
* This file was part of the Independent JPEG Group's software:
* Copyright (C) 1994-1997, Thomas G. Lane.
* Modified 2019 by Guido Vollbeding.
* libjpeg-turbo Modifications:
* Copyright (C) 2017, 2019, D. R. Commander.
* For conditions of distribution and use, see the accompanying README.ijg
@@ -104,7 +105,7 @@ EXTERN(cjpeg_source_ptr) jinit_read_bmp(j_compress_ptr cinfo,
EXTERN(djpeg_dest_ptr) jinit_write_bmp(j_decompress_ptr cinfo, boolean is_os2,
boolean use_inversion_array);
EXTERN(cjpeg_source_ptr) jinit_read_gif(j_compress_ptr cinfo);
EXTERN(djpeg_dest_ptr) jinit_write_gif(j_decompress_ptr cinfo);
EXTERN(djpeg_dest_ptr) jinit_write_gif(j_decompress_ptr cinfo, boolean is_lzw);
EXTERN(cjpeg_source_ptr) jinit_read_ppm(j_compress_ptr cinfo);
EXTERN(djpeg_dest_ptr) jinit_write_ppm(j_decompress_ptr cinfo);
EXTERN(cjpeg_source_ptr) jinit_read_targa(j_compress_ptr cinfo);

31
change.log
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@@ -6,6 +6,25 @@ reference. Please see ChangeLog.md for information specific to libjpeg-turbo.
CHANGE LOG for Independent JPEG Group's JPEG software
Version 9d 12-Jan-2020
-----------------------
Restore GIF read and write support from libjpeg version 6a.
Thank to Wolfgang Werner (W.W.) Heinz for suggestion.
Add jpegtran -drop option; add options to the crop extension and wipe
to fill the extra area with content from the source image region,
instead of gray out.
Version 9c 14-Jan-2018
-----------------------
jpegtran: add an option to the -wipe switch to fill the region
with the average of adjacent blocks, instead of gray out.
Thank to Caitlyn Feddock and Maddie Ziegler for inspiration.
Version 9b 17-Jan-2016
-----------------------
@@ -13,6 +32,13 @@ Document 'f' specifier for jpegtran -crop specification.
Thank to Michele Martone for suggestion.
Version 9a 19-Jan-2014
-----------------------
Add jpegtran -wipe option and extension for -crop.
Thank to Andrew Senior, David Clunie, and Josef Schmid for suggestion.
Version 9 13-Jan-2013
----------------------
@@ -138,11 +164,6 @@ Huffman tables being used.
Huffman tables are checked for validity much more carefully than before.
To avoid the Unisys LZW patent, djpeg's GIF output capability has been
changed to produce "uncompressed GIFs", and cjpeg's GIF input capability
has been removed altogether. We're not happy about it either, but there
seems to be no good alternative.
The configure script now supports building libjpeg as a shared library
on many flavors of Unix (all the ones that GNU libtool knows how to
build shared libraries for). Use "./configure --enable-shared" to

13
cjpeg.1
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@@ -16,7 +16,7 @@ cjpeg \- compress an image file to a JPEG file
compresses the named image file, or the standard input if no file is
named, and produces a JPEG/JFIF file on the standard output.
The currently supported input file formats are: PPM (PBMPLUS color
format), PGM (PBMPLUS grayscale format), BMP, and Targa.
format), PGM (PBMPLUS grayscale format), BMP, GIF, and Targa.
.SH OPTIONS
All switch names may be abbreviated; for example,
.B \-grayscale
@@ -41,10 +41,10 @@ Scale quantization tables to adjust image quality. Quality is 0 (worst) to
.TP
.B \-grayscale
Create monochrome JPEG file from color input. Be sure to use this switch when
compressing a grayscale BMP file, because
compressing a grayscale BMP or GIF file, because
.B cjpeg
isn't bright enough to notice whether a BMP file uses only shades of gray.
By saying
isn't bright enough to notice whether a BMP or GIF file uses only shades of
gray. By saying
.BR \-grayscale,
you'll get a smaller JPEG file that takes less time to process.
.TP
@@ -343,11 +343,6 @@ This file was modified by The libjpeg-turbo Project to include only information
relevant to libjpeg-turbo, to wordsmith certain sections, and to describe
features not present in libjpeg.
.SH ISSUES
Support for GIF input files was removed in cjpeg v6b due to concerns over
the Unisys LZW patent. Although this patent expired in 2006, cjpeg still
lacks GIF support, for these historical reasons. (Conversion of GIF files to
JPEG is usually a bad idea anyway, since GIF is a 256-color format.)
.PP
Not all variants of BMP and Targa file formats are supported.
.PP
The

22
djpeg.1
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@@ -80,9 +80,20 @@ is specified, or if the JPEG file is grayscale; otherwise, 24-bit full-color
format is emitted.
.TP
.B \-gif
Select GIF output format. Since GIF does not support more than 256 colors,
Select GIF output format (LZW-compressed). Since GIF does not support more
than 256 colors,
.B \-colors 256
is assumed (unless you specify a smaller number of colors).
is assumed (unless you specify a smaller number of colors). If you specify
.BR \-fast,
the default number of colors is 216.
.TP
.B \-gif0
Select GIF output format (uncompressed). Since GIF does not support more than
256 colors,
.B \-colors 256
is assumed (unless you specify a smaller number of colors). If you specify
.BR \-fast,
the default number of colors is 216.
.TP
.B \-os2
Select BMP output format (OS/2 1.x flavor). 8-bit colormapped format is
@@ -305,10 +316,3 @@ Independent JPEG Group
This file was modified by The libjpeg-turbo Project to include only information
relevant to libjpeg-turbo, to wordsmith certain sections, and to describe
features not present in libjpeg.
.SH ISSUES
Support for compressed GIF output files was removed in djpeg v6b due to
concerns over the Unisys LZW patent. Although this patent expired in 2006,
djpeg still lacks compressed GIF support, for these historical reasons.
(Conversion of JPEG files to GIF is usually a bad idea anyway, since GIF is a
256-color format.) The uncompressed GIF files that djpeg generates are larger
than they should be, but they are readable by standard GIF decoders.

22
djpeg.c
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@@ -3,7 +3,7 @@
*
* This file was part of the Independent JPEG Group's software:
* Copyright (C) 1991-1997, Thomas G. Lane.
* Modified 2013 by Guido Vollbeding.
* Modified 2013-2019 by Guido Vollbeding.
* libjpeg-turbo Modifications:
* Copyright (C) 2010-2011, 2013-2017, 2019-2020, D. R. Commander.
* Copyright (C) 2015, Google, Inc.
@@ -68,7 +68,8 @@ static const char * const cdjpeg_message_table[] = {
typedef enum {
FMT_BMP, /* BMP format (Windows flavor) */
FMT_GIF, /* GIF format */
FMT_GIF, /* GIF format (LZW-compressed) */
FMT_GIF0, /* GIF format (uncompressed) */
FMT_OS2, /* BMP format (OS/2 flavor) */
FMT_PPM, /* PPM/PGM (PBMPLUS formats) */
FMT_TARGA, /* Targa format */
@@ -129,8 +130,10 @@ usage(void)
(DEFAULT_FMT == FMT_BMP ? " (default)" : ""));
#endif
#ifdef GIF_SUPPORTED
fprintf(stderr, " -gif Select GIF output format%s\n",
fprintf(stderr, " -gif Select GIF output format (LZW-compressed)%s\n",
(DEFAULT_FMT == FMT_GIF ? " (default)" : ""));
fprintf(stderr, " -gif0 Select GIF output format (uncompressed)%s\n",
(DEFAULT_FMT == FMT_GIF0 ? " (default)" : ""));
#endif
#ifdef BMP_SUPPORTED
fprintf(stderr, " -os2 Select BMP output format (OS/2 style)%s\n",
@@ -227,7 +230,7 @@ parse_switches(j_decompress_ptr cinfo, int argc, char **argv,
arg++; /* advance past switch marker character */
if (keymatch(arg, "bmp", 1)) {
/* BMP output format. */
/* BMP output format (Windows flavor). */
requested_fmt = FMT_BMP;
} else if (keymatch(arg, "colors", 1) || keymatch(arg, "colours", 1) ||
@@ -298,9 +301,13 @@ parse_switches(j_decompress_ptr cinfo, int argc, char **argv,
cinfo->do_fancy_upsampling = FALSE;
} else if (keymatch(arg, "gif", 1)) {
/* GIF output format. */
/* GIF output format (LZW-compressed). */
requested_fmt = FMT_GIF;
} else if (keymatch(arg, "gif0", 4)) {
/* GIF output format (uncompressed). */
requested_fmt = FMT_GIF0;
} else if (keymatch(arg, "grayscale", 2) ||
keymatch(arg, "greyscale", 2)) {
/* Force monochrome output. */
@@ -680,7 +687,10 @@ main(int argc, char **argv)
#endif
#ifdef GIF_SUPPORTED
case FMT_GIF:
dest_mgr = jinit_write_gif(&cinfo);
dest_mgr = jinit_write_gif(&cinfo, TRUE);
break;
case FMT_GIF0:
dest_mgr = jinit_write_gif(&cinfo, FALSE);
break;
#endif
#ifdef PPM_SUPPORTED

13
jerror.h
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@@ -207,6 +207,10 @@ JMESSAGE(JWRN_ARITH_BAD_CODE, "Corrupt JPEG data: bad arithmetic code")
#endif
#endif
JMESSAGE(JWRN_BOGUS_ICC, "Corrupt JPEG data: bad ICC marker")
#if JPEG_LIB_VERSION < 70
JMESSAGE(JERR_BAD_DROP_SAMPLING,
"Component index %d: mismatching sampling ratio %d:%d, %d:%d, %c")
#endif
#ifdef JMAKE_ENUM_LIST
@@ -252,6 +256,15 @@ JMESSAGE(JWRN_BOGUS_ICC, "Corrupt JPEG data: bad ICC marker")
(cinfo)->err->msg_parm.i[2] = (p3), \
(cinfo)->err->msg_parm.i[3] = (p4), \
(*(cinfo)->err->error_exit) ((j_common_ptr)(cinfo)))
#define ERREXIT6(cinfo, code, p1, p2, p3, p4, p5, p6) \
((cinfo)->err->msg_code = (code), \
(cinfo)->err->msg_parm.i[0] = (p1), \
(cinfo)->err->msg_parm.i[1] = (p2), \
(cinfo)->err->msg_parm.i[2] = (p3), \
(cinfo)->err->msg_parm.i[3] = (p4), \
(cinfo)->err->msg_parm.i[4] = (p5), \
(cinfo)->err->msg_parm.i[5] = (p6), \
(*(cinfo)->err->error_exit) ((j_common_ptr)(cinfo)))
#define ERREXITS(cinfo, code, str) \
((cinfo)->err->msg_code = (code), \
strncpy((cinfo)->err->msg_parm.s, (str), JMSG_STR_PARM_MAX), \

8
jidctint.c
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@@ -3,7 +3,7 @@
*
* This file was part of the Independent JPEG Group's software:
* Copyright (C) 1991-1998, Thomas G. Lane.
* Modification developed 2002-2009 by Guido Vollbeding.
* Modification developed 2002-2018 by Guido Vollbeding.
* libjpeg-turbo Modifications:
* Copyright (C) 2015, D. R. Commander.
* For conditions of distribution and use, see the accompanying README.ijg
@@ -417,7 +417,7 @@ jpeg_idct_islow(j_decompress_ptr cinfo, jpeg_component_info *compptr,
/*
* Perform dequantization and inverse DCT on one block of coefficients,
* producing a 7x7 output block.
* producing a reduced-size 7x7 output block.
*
* Optimized algorithm with 12 multiplications in the 1-D kernel.
* cK represents sqrt(2) * cos(K*pi/14).
@@ -1258,7 +1258,7 @@ jpeg_idct_10x10(j_decompress_ptr cinfo, jpeg_component_info *compptr,
/*
* Perform dequantization and inverse DCT on one block of coefficients,
* producing a 11x11 output block.
* producing an 11x11 output block.
*
* Optimized algorithm with 24 multiplications in the 1-D kernel.
* cK represents sqrt(2) * cos(K*pi/22).
@@ -2398,7 +2398,7 @@ jpeg_idct_16x16(j_decompress_ptr cinfo, jpeg_component_info *compptr,
tmp0 = DEQUANTIZE(inptr[DCTSIZE * 0], quantptr[DCTSIZE * 0]);
tmp0 = LEFT_SHIFT(tmp0, CONST_BITS);
/* Add fudge factor here for final descale. */
tmp0 += 1 << (CONST_BITS - PASS1_BITS - 1);
tmp0 += ONE << (CONST_BITS - PASS1_BITS - 1);
z1 = DEQUANTIZE(inptr[DCTSIZE * 4], quantptr[DCTSIZE * 4]);
tmp1 = MULTIPLY(z1, FIX(1.306562965)); /* c4[16] = c2[8] */

55
jpegtran.1
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@@ -1,4 +1,4 @@
.TH JPEGTRAN 1 "18 December 2019"
.TH JPEGTRAN 1 "26 October 2020"
.SH NAME
jpegtran \- lossless transformation of JPEG files
.SH SYNOPSIS
@@ -161,13 +161,13 @@ to do a perfect rotation, if available, or an approximated one if not.
.PP
This version of \fBjpegtran\fR also offers a lossless crop option, which
discards data outside of a given image region but losslessly preserves what is
inside. Like the rotate and flip transforms, lossless crop is restricted by the
current JPEG format; the upper left corner of the selected region must fall on
an iMCU boundary. If it doesn't, then it is silently moved up and/or left to
the nearest iMCU boundary (the lower right corner is unchanged.) Thus, the
inside. Like the rotate and flip transforms, lossless crop is restricted by
the current JPEG format; the upper left corner of the selected region must fall
on an iMCU boundary. If it doesn't, then it is silently moved up and/or left
to the nearest iMCU boundary (the lower right corner is unchanged.) Thus, the
output image covers at least the requested region, but it may cover more. The
adjustment of the region dimensions may be optionally disabled by attaching
an 'f' character ("force") to the width or height number.
adjustment of the region dimensions may be optionally disabled by attaching an
'f' character ("force") to the width or height number.
The image can be losslessly cropped by giving the switch:
.TP
@@ -180,6 +180,47 @@ left corner of the selected region must fall on an iMCU boundary. If it
doesn't, then it is silently moved up and/or left to the nearest iMCU boundary
(the lower right corner is unchanged.)
.PP
If W or H is larger than the width/height of the input image, then the output
image is expanded in size, and the expanded region is filled in with zeros
(neutral gray). Attaching an 'f' character ("flatten") to the width number
will cause each block in the expanded region to be filled in with the DC
coefficient of the nearest block in the input image rather than grayed out.
Attaching an 'r' character ("reflect") to the width number will cause the
expanded region to be filled in with repeated reflections of the input image
rather than grayed out.
.PP
A complementary lossless wipe option is provided to discard (gray out) data
inside a given image region while losslessly preserving what is outside:
.TP
.B \-wipe WxH+X+Y
Wipe (gray out) a rectangular region of width W and height H from the input
image, starting at point X,Y.
.PP
Attaching an 'f' character ("flatten") to the width number will cause the
region to be filled with the average of adjacent blocks rather than grayed out.
If the wipe region and the region outside the wipe region, when adjusted to the
nearest iMCU boundary, form two horizontally adjacent rectangles, then
attaching an 'r' character ("reflect") to the width number will cause the wipe
region to be filled with repeated reflections of the outside region rather than
grayed out.
.PP
A lossless drop option is also provided, which allows another JPEG image to be
inserted ("dropped") into the input image data at a given position, replacing
the existing image data at that position:
.TP
.B \-drop +X+Y filename
Drop (insert) another image at point X,Y
.PP
Both the input image and the drop image must have the same subsampling level.
It is best if they also have the same quantization (quality.) Otherwise, the
quantization of the output image will be adapted to accommodate the higher of
the input image quality and the drop image quality. The trim option can be
used with the drop option to requantize the drop image to match the input
image. Note that a grayscale image can be dropped into a full-color image or
vice versa, as long as the full-color image has no vertical subsampling. If
the input image is grayscale and the drop image is full-color, then the
chrominance channels from the drop image will be discarded.
.PP
Other not-strictly-lossless transformation switches are:
.TP
.B \-grayscale

102
jpegtran.c
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@@ -2,7 +2,7 @@
* jpegtran.c
*
* This file was part of the Independent JPEG Group's software:
* Copyright (C) 1995-2010, Thomas G. Lane, Guido Vollbeding.
* Copyright (C) 1995-2019, Thomas G. Lane, Guido Vollbeding.
* libjpeg-turbo Modifications:
* Copyright (C) 2010, 2014, 2017, 2019, D. R. Commander.
* For conditions of distribution and use, see the accompanying README.ijg
@@ -43,6 +43,7 @@ static const char *progname; /* program name for error messages */
static char *icc_filename; /* for -icc switch */
JDIMENSION max_scans; /* for -maxscans switch */
static char *outfilename; /* for -outfile switch */
static char *dropfilename; /* for -drop switch */
boolean report; /* for -report switch */
boolean strict; /* for -strict switch */
static JCOPY_OPTION copyoption; /* -copy switch */
@@ -72,9 +73,10 @@ usage(void)
#endif
fprintf(stderr, "Switches for modifying the image:\n");
#if TRANSFORMS_SUPPORTED
fprintf(stderr, " -crop WxH+X+Y Crop to a rectangular subarea\n");
fprintf(stderr, " -grayscale Reduce to grayscale (omit color data)\n");
fprintf(stderr, " -crop WxH+X+Y Crop to a rectangular region\n");
fprintf(stderr, " -drop +X+Y filename Drop (insert) another image\n");
fprintf(stderr, " -flip [horizontal|vertical] Mirror image (left-right or top-bottom)\n");
fprintf(stderr, " -grayscale Reduce to grayscale (omit color data)\n");
fprintf(stderr, " -perfect Fail if there is non-transformable edge blocks\n");
fprintf(stderr, " -rotate [90|180|270] Rotate image (degrees clockwise)\n");
#endif
@@ -82,6 +84,8 @@ usage(void)
fprintf(stderr, " -transpose Transpose image\n");
fprintf(stderr, " -transverse Transverse transpose image\n");
fprintf(stderr, " -trim Drop non-transformable edge blocks\n");
fprintf(stderr, " with -drop: Requantize drop file to match source file\n");
fprintf(stderr, " -wipe WxH+X+Y Wipe (gray out) a rectangular region\n");
#endif
fprintf(stderr, "Switches for advanced users:\n");
#ifdef C_ARITH_CODING_SUPPORTED
@@ -202,7 +206,8 @@ parse_switches(j_compress_ptr cinfo, int argc, char **argv,
#if TRANSFORMS_SUPPORTED
if (++argn >= argc) /* advance to next argument */
usage();
if (!jtransform_parse_crop_spec(&transformoption, argv[argn])) {
if (transformoption.crop /* reject multiple crop/drop/wipe requests */ ||
!jtransform_parse_crop_spec(&transformoption, argv[argn])) {
fprintf(stderr, "%s: bogus -crop argument '%s'\n",
progname, argv[argn]);
exit(EXIT_FAILURE);
@@ -211,6 +216,26 @@ parse_switches(j_compress_ptr cinfo, int argc, char **argv,
select_transform(JXFORM_NONE); /* force an error */
#endif
} else if (keymatch(arg, "drop", 2)) {
#if TRANSFORMS_SUPPORTED
if (++argn >= argc) /* advance to next argument */
usage();
if (transformoption.crop /* reject multiple crop/drop/wipe requests */ ||
!jtransform_parse_crop_spec(&transformoption, argv[argn]) ||
transformoption.crop_width_set != JCROP_UNSET ||
transformoption.crop_height_set != JCROP_UNSET) {
fprintf(stderr, "%s: bogus -drop argument '%s'\n",
progname, argv[argn]);
exit(EXIT_FAILURE);
}
if (++argn >= argc) /* advance to next argument */
usage();
dropfilename = argv[argn];
select_transform(JXFORM_DROP);
#else
select_transform(JXFORM_NONE); /* force an error */
#endif
} else if (keymatch(arg, "debug", 1) || keymatch(arg, "verbose", 1)) {
/* Enable debug printouts. */
/* On first -d, print version identification */
@@ -371,6 +396,21 @@ parse_switches(j_compress_ptr cinfo, int argc, char **argv,
/* Trim off any partial edge MCUs that the transform can't handle. */
transformoption.trim = TRUE;
} else if (keymatch(arg, "wipe", 1)) {
#if TRANSFORMS_SUPPORTED
if (++argn >= argc) /* advance to next argument */
usage();
if (transformoption.crop /* reject multiple crop/drop/wipe requests */ ||
!jtransform_parse_crop_spec(&transformoption, argv[argn])) {
fprintf(stderr, "%s: bogus -wipe argument '%s'\n",
progname, argv[argn]);
exit(EXIT_FAILURE);
}
select_transform(JXFORM_WIPE);
#else
select_transform(JXFORM_NONE); /* force an error */
#endif
} else {
usage(); /* bogus switch */
}
@@ -417,6 +457,11 @@ int
main(int argc, char **argv)
{
struct jpeg_decompress_struct srcinfo;
#if TRANSFORMS_SUPPORTED
struct jpeg_decompress_struct dropinfo;
struct jpeg_error_mgr jdroperr;
FILE *drop_file;
#endif
struct jpeg_compress_struct dstinfo;
struct jpeg_error_mgr jsrcerr, jdsterr;
struct cdjpeg_progress_mgr src_progress, dst_progress;
@@ -452,7 +497,7 @@ main(int argc, char **argv)
* values read here are mostly ignored; we will rescan the switches after
* opening the input file. Also note that most of the switches affect the
* destination JPEG object, so we parse into that and then copy over what
* needs to affects the source too.
* needs to affect the source too.
*/
file_index = parse_switches(&dstinfo, argc, argv, 0, FALSE);
@@ -536,6 +581,21 @@ main(int argc, char **argv)
src_progress.report = report;
src_progress.max_scans = max_scans;
}
#if TRANSFORMS_SUPPORTED
/* Open the drop file. */
if (dropfilename != NULL) {
if ((drop_file = fopen(dropfilename, READ_BINARY)) == NULL) {
fprintf(stderr, "%s: can't open %s for reading\n", progname,
dropfilename);
exit(EXIT_FAILURE);
}
dropinfo.err = jpeg_std_error(&jdroperr);
jpeg_create_decompress(&dropinfo);
jpeg_stdio_src(&dropinfo, drop_file);
} else {
drop_file = NULL;
}
#endif
/* Specify data source for decompression */
jpeg_stdio_src(&srcinfo, fp);
@@ -546,6 +606,17 @@ main(int argc, char **argv)
/* Read file header */
(void)jpeg_read_header(&srcinfo, TRUE);
#if TRANSFORMS_SUPPORTED
if (dropfilename != NULL) {
(void)jpeg_read_header(&dropinfo, TRUE);
transformoption.crop_width = dropinfo.image_width;
transformoption.crop_width_set = JCROP_POS;
transformoption.crop_height = dropinfo.image_height;
transformoption.crop_height_set = JCROP_POS;
transformoption.drop_ptr = &dropinfo;
}
#endif
/* Any space needed by a transform option must be requested before
* jpeg_read_coefficients so that memory allocation will be done right.
*/
@@ -561,6 +632,12 @@ main(int argc, char **argv)
/* Read source file as DCT coefficients */
src_coef_arrays = jpeg_read_coefficients(&srcinfo);
#if TRANSFORMS_SUPPORTED
if (dropfilename != NULL) {
transformoption.drop_coef_arrays = jpeg_read_coefficients(&dropinfo);
}
#endif
/* Initialize destination compression parameters from source values */
jpeg_copy_critical_parameters(&srcinfo, &dstinfo);
@@ -621,12 +698,22 @@ main(int argc, char **argv)
/* Finish compression and release memory */
jpeg_finish_compress(&dstinfo);
jpeg_destroy_compress(&dstinfo);
#if TRANSFORMS_SUPPORTED
if (dropfilename != NULL) {
(void)jpeg_finish_decompress(&dropinfo);
jpeg_destroy_decompress(&dropinfo);
}
#endif
(void)jpeg_finish_decompress(&srcinfo);
jpeg_destroy_decompress(&srcinfo);
/* Close output file, if we opened it */
if (fp != stdout)
fclose(fp);
#if TRANSFORMS_SUPPORTED
if (drop_file != NULL)
fclose(drop_file);
#endif
if (report)
end_progress_monitor((j_common_ptr)&dstinfo);
@@ -636,6 +723,11 @@ main(int argc, char **argv)
free(icc_profile);
/* All done. */
#if TRANSFORMS_SUPPORTED
if (dropfilename != NULL)
exit(jsrcerr.num_warnings + jdroperr.num_warnings +
jdsterr.num_warnings ? EXIT_WARNING : EXIT_SUCCESS);
#endif
exit(jsrcerr.num_warnings + jdsterr.num_warnings ?
EXIT_WARNING : EXIT_SUCCESS);
return 0; /* suppress no-return-value warnings */

4
jversion.h
View File

@@ -2,7 +2,7 @@
* jversion.h
*
* This file was part of the Independent JPEG Group's software:
* Copyright (C) 1991-2012, Thomas G. Lane, Guido Vollbeding.
* Copyright (C) 1991-2020, Thomas G. Lane, Guido Vollbeding.
* libjpeg-turbo Modifications:
* Copyright (C) 2010, 2012-2020, D. R. Commander.
* For conditions of distribution and use, see the accompanying README.ijg
@@ -48,7 +48,7 @@
"Copyright (C) 2009, 2012 Pierre Ossman for Cendio AB\n" \
"Copyright (C) 2009-2011 Nokia Corporation and/or its subsidiary(-ies)\n" \
"Copyright (C) 1999-2006 MIYASAKA Masaru\n" \
"Copyright (C) 1991-2017 Thomas G. Lane, Guido Vollbeding"
"Copyright (C) 1991-2020 Thomas G. Lane, Guido Vollbeding"
#define JCOPYRIGHT_SHORT \
"Copyright (C) 1991-2020 The libjpeg-turbo Project and many others"

12
rdbmp.c
View File

@@ -12,7 +12,7 @@
*
* This file contains routines to read input images in Microsoft "BMP"
* format (MS Windows 3.x, OS/2 1.x, and OS/2 2.x flavors).
* Currently, only 8-bit and 24-bit images are supported, not 1-bit or
* Currently, only 8-, 24-, and 32-bit images are supported, not 1-bit or
* 4-bit (feeding such low-depth images into JPEG would be silly anyway).
* Also, we don't support RLE-compressed files.
*
@@ -61,7 +61,7 @@ typedef struct _bmp_source_struct {
JDIMENSION source_row; /* Current source row number */
JDIMENSION row_width; /* Physical width of scanlines in file */
int bits_per_pixel; /* remembers 8- or 24-bit format */
int bits_per_pixel; /* remembers 8-, 24-, or 32-bit format */
int cmap_length; /* colormap length */
boolean use_inversion_array; /* TRUE = preload the whole image, which is
@@ -469,7 +469,9 @@ start_input_bmp(j_compress_ptr cinfo, cjpeg_source_ptr sinfo)
TRACEMS2(cinfo, 1, JTRC_BMP_OS2_MAPPED, biWidth, biHeight);
break;
case 24: /* RGB image */
TRACEMS2(cinfo, 1, JTRC_BMP_OS2, biWidth, biHeight);
case 32: /* RGB image + Alpha channel */
TRACEMS3(cinfo, 1, JTRC_BMP_OS2, biWidth, biHeight,
source->bits_per_pixel);
break;
default:
ERREXIT(cinfo, JERR_BMP_BADDEPTH);
@@ -496,10 +498,8 @@ start_input_bmp(j_compress_ptr cinfo, cjpeg_source_ptr sinfo)
TRACEMS2(cinfo, 1, JTRC_BMP_MAPPED, biWidth, biHeight);
break;
case 24: /* RGB image */
TRACEMS2(cinfo, 1, JTRC_BMP, biWidth, biHeight);
break;
case 32: /* RGB image + Alpha channel */
TRACEMS2(cinfo, 1, JTRC_BMP, biWidth, biHeight);
TRACEMS3(cinfo, 1, JTRC_BMP, biWidth, biHeight, source->bits_per_pixel);
break;
default:
ERREXIT(cinfo, JERR_BMP_BADDEPTH);

663
rdgif.c
View File

@@ -2,28 +2,656 @@
* rdgif.c
*
* Copyright (C) 1991-1997, Thomas G. Lane.
* Modified 2019 by Guido Vollbeding.
* This file is part of the Independent JPEG Group's software.
* For conditions of distribution and use, see the accompanying README.ijg
* file.
*
* This file contains routines to read input images in GIF format.
*
*****************************************************************************
* NOTE: to avoid entanglements with Unisys' patent on LZW compression, *
* the ability to read GIF files has been removed from the IJG distribution. *
* Sorry about that. *
*****************************************************************************
*
* We are required to state that
* "The Graphics Interchange Format(c) is the Copyright property of
* CompuServe Incorporated. GIF(sm) is a Service Mark property of
* CompuServe Incorporated."
* These routines may need modification for non-Unix environments or
* specialized applications. As they stand, they assume input from
* an ordinary stdio stream. They further assume that reading begins
* at the start of the file; start_input may need work if the
* user interface has already read some data (e.g., to determine that
* the file is indeed GIF format).
*/
/*
* This code is loosely based on giftoppm from the PBMPLUS distribution
* of Feb. 1991. That file contains the following copyright notice:
* +-------------------------------------------------------------------+
* | Copyright 1990, David Koblas. |
* | Permission to use, copy, modify, and distribute this software |
* | and its documentation for any purpose and without fee is hereby |
* | granted, provided that the above copyright notice appear in all |
* | copies and that both that copyright notice and this permission |
* | notice appear in supporting documentation. This software is |
* | provided "as is" without express or implied warranty. |
* +-------------------------------------------------------------------+
*/
#include "cdjpeg.h" /* Common decls for cjpeg/djpeg applications */
#ifdef GIF_SUPPORTED
/* Macros to deal with unsigned chars as efficiently as compiler allows */
typedef unsigned char U_CHAR;
#define UCH(x) ((int)(x))
#define ReadOK(file, buffer, len) \
(JFREAD(file, buffer, len) == ((size_t)(len)))
#define MAXCOLORMAPSIZE 256 /* max # of colors in a GIF colormap */
#define NUMCOLORS 3 /* # of colors */
#define CM_RED 0 /* color component numbers */
#define CM_GREEN 1
#define CM_BLUE 2
#define MAX_LZW_BITS 12 /* maximum LZW code size */
#define LZW_TABLE_SIZE (1 << MAX_LZW_BITS) /* # of possible LZW symbols */
/* Macros for extracting header data --- note we assume chars may be signed */
#define LM_to_uint(array, offset) \
((unsigned int)UCH(array[offset]) + \
(((unsigned int)UCH(array[offset + 1])) << 8))
#define BitSet(byte, bit) ((byte) & (bit))
#define INTERLACE 0x40 /* mask for bit signifying interlaced image */
#define COLORMAPFLAG 0x80 /* mask for bit signifying colormap presence */
/*
* LZW decompression tables look like this:
* symbol_head[K] = prefix symbol of any LZW symbol K (0..LZW_TABLE_SIZE-1)
* symbol_tail[K] = suffix byte of any LZW symbol K (0..LZW_TABLE_SIZE-1)
* Note that entries 0..end_code of the above tables are not used,
* since those symbols represent raw bytes or special codes.
*
* The stack represents the not-yet-used expansion of the last LZW symbol.
* In the worst case, a symbol could expand to as many bytes as there are
* LZW symbols, so we allocate LZW_TABLE_SIZE bytes for the stack.
* (This is conservative since that number includes the raw-byte symbols.)
*/
/* Private version of data source object */
typedef struct {
struct cjpeg_source_struct pub; /* public fields */
j_compress_ptr cinfo; /* back link saves passing separate parm */
JSAMPARRAY colormap; /* GIF colormap (converted to my format) */
/* State for GetCode and LZWReadByte */
U_CHAR code_buf[256 + 4]; /* current input data block */
int last_byte; /* # of bytes in code_buf */
int last_bit; /* # of bits in code_buf */
int cur_bit; /* next bit index to read */
boolean first_time; /* flags first call to GetCode */
boolean out_of_blocks; /* TRUE if hit terminator data block */
int input_code_size; /* codesize given in GIF file */
int clear_code, end_code; /* values for Clear and End codes */
int code_size; /* current actual code size */
int limit_code; /* 2^code_size */
int max_code; /* first unused code value */
/* Private state for LZWReadByte */
int oldcode; /* previous LZW symbol */
int firstcode; /* first byte of oldcode's expansion */
/* LZW symbol table and expansion stack */
UINT16 *symbol_head; /* => table of prefix symbols */
UINT8 *symbol_tail; /* => table of suffix bytes */
UINT8 *symbol_stack; /* => stack for symbol expansions */
UINT8 *sp; /* stack pointer */
/* State for interlaced image processing */
boolean is_interlaced; /* TRUE if have interlaced image */
jvirt_sarray_ptr interlaced_image; /* full image in interlaced order */
JDIMENSION cur_row_number; /* need to know actual row number */
JDIMENSION pass2_offset; /* # of pixel rows in pass 1 */
JDIMENSION pass3_offset; /* # of pixel rows in passes 1&2 */
JDIMENSION pass4_offset; /* # of pixel rows in passes 1,2,3 */
} gif_source_struct;
typedef gif_source_struct *gif_source_ptr;
/* Forward declarations */
METHODDEF(JDIMENSION) get_pixel_rows(j_compress_ptr cinfo,
cjpeg_source_ptr sinfo);
METHODDEF(JDIMENSION) load_interlaced_image(j_compress_ptr cinfo,
cjpeg_source_ptr sinfo);
METHODDEF(JDIMENSION) get_interlaced_row(j_compress_ptr cinfo,
cjpeg_source_ptr sinfo);
LOCAL(int)
ReadByte(gif_source_ptr sinfo)
/* Read next byte from GIF file */
{
register FILE *infile = sinfo->pub.input_file;
register int c;
if ((c = getc(infile)) == EOF)
ERREXIT(sinfo->cinfo, JERR_INPUT_EOF);
return c;
}
LOCAL(int)
GetDataBlock(gif_source_ptr sinfo, U_CHAR *buf)
/* Read a GIF data block, which has a leading count byte */
/* A zero-length block marks the end of a data block sequence */
{
int count;
count = ReadByte(sinfo);
if (count > 0) {
if (!ReadOK(sinfo->pub.input_file, buf, count))
ERREXIT(sinfo->cinfo, JERR_INPUT_EOF);
}
return count;
}
LOCAL(void)
SkipDataBlocks(gif_source_ptr sinfo)
/* Skip a series of data blocks, until a block terminator is found */
{
U_CHAR buf[256];
while (GetDataBlock(sinfo, buf) > 0)
/* skip */;
}
LOCAL(void)
ReInitLZW(gif_source_ptr sinfo)
/* (Re)initialize LZW state; shared code for startup and Clear processing */
{
sinfo->code_size = sinfo->input_code_size + 1;
sinfo->limit_code = sinfo->clear_code << 1; /* 2^code_size */
sinfo->max_code = sinfo->clear_code + 2; /* first unused code value */
sinfo->sp = sinfo->symbol_stack; /* init stack to empty */
}
LOCAL(void)
InitLZWCode(gif_source_ptr sinfo)
/* Initialize for a series of LZWReadByte (and hence GetCode) calls */
{
/* GetCode initialization */
sinfo->last_byte = 2; /* make safe to "recopy last two bytes" */
sinfo->code_buf[0] = 0;
sinfo->code_buf[1] = 0;
sinfo->last_bit = 0; /* nothing in the buffer */
sinfo->cur_bit = 0; /* force buffer load on first call */
sinfo->first_time = TRUE;
sinfo->out_of_blocks = FALSE;
/* LZWReadByte initialization: */
/* compute special code values (note that these do not change later) */
sinfo->clear_code = 1 << sinfo->input_code_size;
sinfo->end_code = sinfo->clear_code + 1;
ReInitLZW(sinfo);
}
LOCAL(int)
GetCode(gif_source_ptr sinfo)
/* Fetch the next code_size bits from the GIF data */
/* We assume code_size is less than 16 */
{
register int accum;
int offs, count;
while (sinfo->cur_bit + sinfo->code_size > sinfo->last_bit) {
/* Time to reload the buffer */
/* First time, share code with Clear case */
if (sinfo->first_time) {
sinfo->first_time = FALSE;
return sinfo->clear_code;
}
if (sinfo->out_of_blocks) {
WARNMS(sinfo->cinfo, JWRN_GIF_NOMOREDATA);
return sinfo->end_code; /* fake something useful */
}
/* preserve last two bytes of what we have -- assume code_size <= 16 */
sinfo->code_buf[0] = sinfo->code_buf[sinfo->last_byte-2];
sinfo->code_buf[1] = sinfo->code_buf[sinfo->last_byte-1];
/* Load more bytes; set flag if we reach the terminator block */
if ((count = GetDataBlock(sinfo, &sinfo->code_buf[2])) == 0) {
sinfo->out_of_blocks = TRUE;
WARNMS(sinfo->cinfo, JWRN_GIF_NOMOREDATA);
return sinfo->end_code; /* fake something useful */
}
/* Reset counters */
sinfo->cur_bit = (sinfo->cur_bit - sinfo->last_bit) + 16;
sinfo->last_byte = 2 + count;
sinfo->last_bit = sinfo->last_byte * 8;
}
/* Form up next 24 bits in accum */
offs = sinfo->cur_bit >> 3; /* byte containing cur_bit */
accum = UCH(sinfo->code_buf[offs + 2]);
accum <<= 8;
accum |= UCH(sinfo->code_buf[offs + 1]);
accum <<= 8;
accum |= UCH(sinfo->code_buf[offs]);
/* Right-align cur_bit in accum, then mask off desired number of bits */
accum >>= (sinfo->cur_bit & 7);
sinfo->cur_bit += sinfo->code_size;
return accum & ((1 << sinfo->code_size) - 1);
}
LOCAL(int)
LZWReadByte(gif_source_ptr sinfo)
/* Read an LZW-compressed byte */
{
register int code; /* current working code */
int incode; /* saves actual input code */
/* If any codes are stacked from a previously read symbol, return them */
if (sinfo->sp > sinfo->symbol_stack)
return (int)(*(--sinfo->sp));
/* Time to read a new symbol */
code = GetCode(sinfo);
if (code == sinfo->clear_code) {
/* Reinit state, swallow any extra Clear codes, and */
/* return next code, which is expected to be a raw byte. */
ReInitLZW(sinfo);
do {
code = GetCode(sinfo);
} while (code == sinfo->clear_code);
if (code > sinfo->clear_code) { /* make sure it is a raw byte */
WARNMS(sinfo->cinfo, JWRN_GIF_BADDATA);
code = 0; /* use something valid */
}
/* make firstcode, oldcode valid! */
sinfo->firstcode = sinfo->oldcode = code;
return code;
}
if (code == sinfo->end_code) {
/* Skip the rest of the image, unless GetCode already read terminator */
if (!sinfo->out_of_blocks) {
SkipDataBlocks(sinfo);
sinfo->out_of_blocks = TRUE;
}
/* Complain that there's not enough data */
WARNMS(sinfo->cinfo, JWRN_GIF_ENDCODE);
/* Pad data with 0's */
return 0; /* fake something usable */
}
/* Got normal raw byte or LZW symbol */
incode = code; /* save for a moment */
if (code >= sinfo->max_code) { /* special case for not-yet-defined symbol */
/* code == max_code is OK; anything bigger is bad data */
if (code > sinfo->max_code) {
WARNMS(sinfo->cinfo, JWRN_GIF_BADDATA);
incode = 0; /* prevent creation of loops in symbol table */
}
/* this symbol will be defined as oldcode/firstcode */
*(sinfo->sp++) = (UINT8)sinfo->firstcode;
code = sinfo->oldcode;
}
/* If it's a symbol, expand it into the stack */
while (code >= sinfo->clear_code) {
*(sinfo->sp++) = sinfo->symbol_tail[code]; /* tail is a byte value */
code = sinfo->symbol_head[code]; /* head is another LZW symbol */
}
/* At this point code just represents a raw byte */
sinfo->firstcode = code; /* save for possible future use */
/* If there's room in table... */
if ((code = sinfo->max_code) < LZW_TABLE_SIZE) {
/* Define a new symbol = prev sym + head of this sym's expansion */
sinfo->symbol_head[code] = (UINT16)sinfo->oldcode;
sinfo->symbol_tail[code] = (UINT8)sinfo->firstcode;
sinfo->max_code++;
/* Is it time to increase code_size? */
if (sinfo->max_code >= sinfo->limit_code &&
sinfo->code_size < MAX_LZW_BITS) {
sinfo->code_size++;
sinfo->limit_code <<= 1; /* keep equal to 2^code_size */
}
}
sinfo->oldcode = incode; /* save last input symbol for future use */
return sinfo->firstcode; /* return first byte of symbol's expansion */
}
LOCAL(void)
ReadColorMap(gif_source_ptr sinfo, int cmaplen, JSAMPARRAY cmap)
/* Read a GIF colormap */
{
int i;
for (i = 0; i < cmaplen; i++) {
#if BITS_IN_JSAMPLE == 8
#define UPSCALE(x) (x)
#else
#define UPSCALE(x) ((x) << (BITS_IN_JSAMPLE - 8))
#endif
cmap[CM_RED][i] = (JSAMPLE)UPSCALE(ReadByte(sinfo));
cmap[CM_GREEN][i] = (JSAMPLE)UPSCALE(ReadByte(sinfo));
cmap[CM_BLUE][i] = (JSAMPLE)UPSCALE(ReadByte(sinfo));
}
}
LOCAL(void)
DoExtension(gif_source_ptr sinfo)
/* Process an extension block */
/* Currently we ignore 'em all */
{
int extlabel;
/* Read extension label byte */
extlabel = ReadByte(sinfo);
TRACEMS1(sinfo->cinfo, 1, JTRC_GIF_EXTENSION, extlabel);
/* Skip the data block(s) associated with the extension */
SkipDataBlocks(sinfo);
}
/*
* Read the file header; return image size and component count.
*/
METHODDEF(void)
start_input_gif(j_compress_ptr cinfo, cjpeg_source_ptr sinfo)
{
gif_source_ptr source = (gif_source_ptr)sinfo;
U_CHAR hdrbuf[10]; /* workspace for reading control blocks */
unsigned int width, height; /* image dimensions */
int colormaplen, aspectRatio;
int c;
/* Read and verify GIF Header */
if (!ReadOK(source->pub.input_file, hdrbuf, 6))
ERREXIT(cinfo, JERR_GIF_NOT);
if (hdrbuf[0] != 'G' || hdrbuf[1] != 'I' || hdrbuf[2] != 'F')
ERREXIT(cinfo, JERR_GIF_NOT);
/* Check for expected version numbers.
* If unknown version, give warning and try to process anyway;
* this is per recommendation in GIF89a standard.
*/
if ((hdrbuf[3] != '8' || hdrbuf[4] != '7' || hdrbuf[5] != 'a') &&
(hdrbuf[3] != '8' || hdrbuf[4] != '9' || hdrbuf[5] != 'a'))
TRACEMS3(cinfo, 1, JTRC_GIF_BADVERSION, hdrbuf[3], hdrbuf[4], hdrbuf[5]);
/* Read and decipher Logical Screen Descriptor */
if (!ReadOK(source->pub.input_file, hdrbuf, 7))
ERREXIT(cinfo, JERR_INPUT_EOF);
width = LM_to_uint(hdrbuf, 0);
height = LM_to_uint(hdrbuf, 2);
/* we ignore the color resolution, sort flag, and background color index */
aspectRatio = UCH(hdrbuf[6]);
if (aspectRatio != 0 && aspectRatio != 49)
TRACEMS(cinfo, 1, JTRC_GIF_NONSQUARE);
/* Allocate space to store the colormap */
source->colormap = (*cinfo->mem->alloc_sarray)
((j_common_ptr)cinfo, JPOOL_IMAGE, (JDIMENSION)MAXCOLORMAPSIZE,
(JDIMENSION)NUMCOLORS);
colormaplen = 0; /* indicate initialization */
/* Read global colormap if header indicates it is present */
if (BitSet(hdrbuf[4], COLORMAPFLAG)) {
colormaplen = 2 << (hdrbuf[4] & 0x07);
ReadColorMap(source, colormaplen, source->colormap);
}
/* Scan until we reach start of desired image.
* We don't currently support skipping images, but could add it easily.
*/
for (;;) {
c = ReadByte(source);
if (c == ';') /* GIF terminator?? */
ERREXIT(cinfo, JERR_GIF_IMAGENOTFOUND);
if (c == '!') { /* Extension */
DoExtension(source);
continue;
}
if (c != ',') { /* Not an image separator? */
WARNMS1(cinfo, JWRN_GIF_CHAR, c);
continue;
}
/* Read and decipher Local Image Descriptor */
if (!ReadOK(source->pub.input_file, hdrbuf, 9))
ERREXIT(cinfo, JERR_INPUT_EOF);
/* we ignore top/left position info, also sort flag */
width = LM_to_uint(hdrbuf, 4);
height = LM_to_uint(hdrbuf, 6);
source->is_interlaced = (BitSet(hdrbuf[8], INTERLACE) != 0);
/* Read local colormap if header indicates it is present */
/* Note: if we wanted to support skipping images, */
/* we'd need to skip rather than read colormap for ignored images */
if (BitSet(hdrbuf[8], COLORMAPFLAG)) {
colormaplen = 2 << (hdrbuf[8] & 0x07);
ReadColorMap(source, colormaplen, source->colormap);
}
source->input_code_size = ReadByte(source); /* get min-code-size byte */
if (source->input_code_size < 2 || source->input_code_size > 8)
ERREXIT1(cinfo, JERR_GIF_CODESIZE, source->input_code_size);
/* Reached desired image, so break out of loop */
/* If we wanted to skip this image, */
/* we'd call SkipDataBlocks and then continue the loop */
break;
}
/* Prepare to read selected image: first initialize LZW decompressor */
source->symbol_head = (UINT16 *)
(*cinfo->mem->alloc_large) ((j_common_ptr)cinfo, JPOOL_IMAGE,
LZW_TABLE_SIZE * sizeof(UINT16));
source->symbol_tail = (UINT8 *)
(*cinfo->mem->alloc_large) ((j_common_ptr)cinfo, JPOOL_IMAGE,
LZW_TABLE_SIZE * sizeof(UINT8));
source->symbol_stack = (UINT8 *)
(*cinfo->mem->alloc_large) ((j_common_ptr)cinfo, JPOOL_IMAGE,
LZW_TABLE_SIZE * sizeof(UINT8));
InitLZWCode(source);
/*
* If image is interlaced, we read it into a full-size sample array,
* decompressing as we go; then get_interlaced_row selects rows from the
* sample array in the proper order.
*/
if (source->is_interlaced) {
/* We request the virtual array now, but can't access it until virtual
* arrays have been allocated. Hence, the actual work of reading the
* image is postponed until the first call to get_pixel_rows.
*/
source->interlaced_image = (*cinfo->mem->request_virt_sarray)
((j_common_ptr)cinfo, JPOOL_IMAGE, FALSE,
(JDIMENSION)width, (JDIMENSION)height, (JDIMENSION)1);
if (cinfo->progress != NULL) {
cd_progress_ptr progress = (cd_progress_ptr)cinfo->progress;
progress->total_extra_passes++; /* count file input as separate pass */
}
source->pub.get_pixel_rows = load_interlaced_image;
} else {
source->pub.get_pixel_rows = get_pixel_rows;
}
/* Create compressor input buffer. */
source->pub.buffer = (*cinfo->mem->alloc_sarray)
((j_common_ptr)cinfo, JPOOL_IMAGE, (JDIMENSION)width * NUMCOLORS,
(JDIMENSION)1);
source->pub.buffer_height = 1;
/* Pad colormap for safety. */
for (c = colormaplen; c < source->clear_code; c++) {
source->colormap[CM_RED][c] =
source->colormap[CM_GREEN][c] =
source->colormap[CM_BLUE][c] = CENTERJSAMPLE;
}
/* Return info about the image. */
cinfo->in_color_space = JCS_RGB;
cinfo->input_components = NUMCOLORS;
cinfo->data_precision = BITS_IN_JSAMPLE; /* we always rescale data to this */
cinfo->image_width = width;
cinfo->image_height = height;
TRACEMS3(cinfo, 1, JTRC_GIF, width, height, colormaplen);
}
/*
* Read one row of pixels.
* This version is used for noninterlaced GIF images:
* we read directly from the GIF file.
*/
METHODDEF(JDIMENSION)
get_pixel_rows(j_compress_ptr cinfo, cjpeg_source_ptr sinfo)
{
gif_source_ptr source = (gif_source_ptr)sinfo;
register int c;
register JSAMPROW ptr;
register JDIMENSION col;
register JSAMPARRAY colormap = source->colormap;
ptr = source->pub.buffer[0];
for (col = cinfo->image_width; col > 0; col--) {
c = LZWReadByte(source);
*ptr++ = colormap[CM_RED][c];
*ptr++ = colormap[CM_GREEN][c];
*ptr++ = colormap[CM_BLUE][c];
}
return 1;
}
/*
* Read one row of pixels.
* This version is used for the first call on get_pixel_rows when
* reading an interlaced GIF file: we read the whole image into memory.
*/
METHODDEF(JDIMENSION)
load_interlaced_image(j_compress_ptr cinfo, cjpeg_source_ptr sinfo)
{
gif_source_ptr source = (gif_source_ptr)sinfo;
register JSAMPROW sptr;
register JDIMENSION col;
JDIMENSION row;
cd_progress_ptr progress = (cd_progress_ptr)cinfo->progress;
/* Read the interlaced image into the virtual array we've created. */
for (row = 0; row < cinfo->image_height; row++) {
if (progress != NULL) {
progress->pub.pass_counter = (long)row;
progress->pub.pass_limit = (long)cinfo->image_height;
(*progress->pub.progress_monitor) ((j_common_ptr)cinfo);
}
sptr = *(*cinfo->mem->access_virt_sarray)
((j_common_ptr)cinfo, source->interlaced_image, row, (JDIMENSION)1,
TRUE);
for (col = cinfo->image_width; col > 0; col--) {
*sptr++ = (JSAMPLE)LZWReadByte(source);
}
}
if (progress != NULL)
progress->completed_extra_passes++;
/* Replace method pointer so subsequent calls don't come here. */
source->pub.get_pixel_rows = get_interlaced_row;
/* Initialize for get_interlaced_row, and perform first call on it. */
source->cur_row_number = 0;
source->pass2_offset = (cinfo->image_height + 7) / 8;
source->pass3_offset = source->pass2_offset + (cinfo->image_height + 3) / 8;
source->pass4_offset = source->pass3_offset + (cinfo->image_height + 1) / 4;
return get_interlaced_row(cinfo, sinfo);
}
/*
* Read one row of pixels.
* This version is used for interlaced GIF images:
* we read from the virtual array.
*/
METHODDEF(JDIMENSION)
get_interlaced_row(j_compress_ptr cinfo, cjpeg_source_ptr sinfo)
{
gif_source_ptr source = (gif_source_ptr)sinfo;
register int c;
register JSAMPROW sptr, ptr;
register JDIMENSION col;
register JSAMPARRAY colormap = source->colormap;
JDIMENSION irow;
/* Figure out which row of interlaced image is needed, and access it. */
switch ((int)(source->cur_row_number & 7)) {
case 0: /* first-pass row */
irow = source->cur_row_number >> 3;
break;
case 4: /* second-pass row */
irow = (source->cur_row_number >> 3) + source->pass2_offset;
break;
case 2: /* third-pass row */
case 6:
irow = (source->cur_row_number >> 2) + source->pass3_offset;
break;
default: /* fourth-pass row */
irow = (source->cur_row_number >> 1) + source->pass4_offset;
}
sptr = *(*cinfo->mem->access_virt_sarray)
((j_common_ptr)cinfo, source->interlaced_image, irow, (JDIMENSION)1,
FALSE);
/* Scan the row, expand colormap, and output */
ptr = source->pub.buffer[0];
for (col = cinfo->image_width; col > 0; col--) {
c = *sptr++;
*ptr++ = colormap[CM_RED][c];
*ptr++ = colormap[CM_GREEN][c];
*ptr++ = colormap[CM_BLUE][c];
}
source->cur_row_number++; /* for next time */
return 1;
}
/*
* Finish up at the end of the file.
*/
METHODDEF(void)
finish_input_gif(j_compress_ptr cinfo, cjpeg_source_ptr sinfo)
{
/* no work */
}
/*
* The module selection routine for GIF format input.
*/
@@ -31,9 +659,18 @@
GLOBAL(cjpeg_source_ptr)
jinit_read_gif(j_compress_ptr cinfo)
{
fprintf(stderr, "GIF input is unsupported for legal reasons. Sorry.\n");
exit(EXIT_FAILURE);
return NULL; /* keep compiler happy */
gif_source_ptr source;
/* Create module interface object */
source = (gif_source_ptr)
(*cinfo->mem->alloc_small) ((j_common_ptr)cinfo, JPOOL_IMAGE,
sizeof(gif_source_struct));
source->cinfo = cinfo; /* make back link for subroutines */
/* Fill in method ptrs, except get_pixel_rows which start_input sets */
source->pub.start_input = start_input_gif;
source->pub.finish_input = finish_input_gif;
return (cjpeg_source_ptr)source;
}
#endif /* GIF_SUPPORTED */

826
transupp.c
View File

@@ -2,7 +2,7 @@
* transupp.c
*
* This file was part of the Independent JPEG Group's software:
* Copyright (C) 1997-2011, Thomas G. Lane, Guido Vollbeding.
* Copyright (C) 1997-2019, Thomas G. Lane, Guido Vollbeding.
* libjpeg-turbo Modifications:
* Copyright (C) 2010, 2017, D. R. Commander.
* For conditions of distribution and use, see the accompanying README.ijg
@@ -88,6 +88,189 @@
*/
LOCAL(void)
dequant_comp(j_decompress_ptr cinfo, jpeg_component_info *compptr,
jvirt_barray_ptr coef_array, JQUANT_TBL *qtblptr1)
{
JDIMENSION blk_x, blk_y;
int offset_y, k;
JQUANT_TBL *qtblptr;
JBLOCKARRAY buffer;
JBLOCKROW block;
JCOEFPTR ptr;
qtblptr = compptr->quant_table;
for (blk_y = 0; blk_y < compptr->height_in_blocks;
blk_y += compptr->v_samp_factor) {
buffer = (*cinfo->mem->access_virt_barray)
((j_common_ptr)cinfo, coef_array, blk_y,
(JDIMENSION)compptr->v_samp_factor, TRUE);
for (offset_y = 0; offset_y < compptr->v_samp_factor; offset_y++) {
block = buffer[offset_y];
for (blk_x = 0; blk_x < compptr->width_in_blocks; blk_x++) {
ptr = block[blk_x];
for (k = 0; k < DCTSIZE2; k++)
if (qtblptr->quantval[k] != qtblptr1->quantval[k])
ptr[k] *= qtblptr->quantval[k] / qtblptr1->quantval[k];
}
}
}
}
LOCAL(void)
requant_comp(j_decompress_ptr cinfo, jpeg_component_info *compptr,
jvirt_barray_ptr coef_array, JQUANT_TBL *qtblptr1)
{
JDIMENSION blk_x, blk_y;
int offset_y, k;
JQUANT_TBL *qtblptr;
JBLOCKARRAY buffer;
JBLOCKROW block;
JCOEFPTR ptr;
JCOEF temp, qval;
qtblptr = compptr->quant_table;
for (blk_y = 0; blk_y < compptr->height_in_blocks;
blk_y += compptr->v_samp_factor) {
buffer = (*cinfo->mem->access_virt_barray)
((j_common_ptr)cinfo, coef_array, blk_y,
(JDIMENSION)compptr->v_samp_factor, TRUE);
for (offset_y = 0; offset_y < compptr->v_samp_factor; offset_y++) {
block = buffer[offset_y];
for (blk_x = 0; blk_x < compptr->width_in_blocks; blk_x++) {
ptr = block[blk_x];
for (k = 0; k < DCTSIZE2; k++) {
temp = qtblptr->quantval[k];
qval = qtblptr1->quantval[k];
if (temp != qval) {
temp *= ptr[k];
/* The following quantization code is copied from jcdctmgr.c */
#ifdef FAST_DIVIDE
#define DIVIDE_BY(a, b) a /= b
#else
#define DIVIDE_BY(a, b) if (a >= b) a /= b; else a = 0
#endif
if (temp < 0) {
temp = -temp;
temp += qval >> 1; /* for rounding */
DIVIDE_BY(temp, qval);
temp = -temp;
} else {
temp += qval >> 1; /* for rounding */
DIVIDE_BY(temp, qval);
}
ptr[k] = temp;
}
}
}
}
}
}
/*
* Calculate largest common denominator using Euclid's algorithm.
*/
LOCAL(JCOEF)
largest_common_denominator(JCOEF a, JCOEF b)
{
JCOEF c;
do {
c = a % b;
a = b;
b = c;
} while (c);
return a;
}
LOCAL(void)
adjust_quant(j_decompress_ptr srcinfo, jvirt_barray_ptr *src_coef_arrays,
j_decompress_ptr dropinfo, jvirt_barray_ptr *drop_coef_arrays,
boolean trim, j_compress_ptr dstinfo)
{
jpeg_component_info *compptr1, *compptr2;
JQUANT_TBL *qtblptr1, *qtblptr2, *qtblptr3;
int ci, k;
for (ci = 0; ci < dstinfo->num_components && ci < dropinfo->num_components;
ci++) {
compptr1 = srcinfo->comp_info + ci;
compptr2 = dropinfo->comp_info + ci;
qtblptr1 = compptr1->quant_table;
qtblptr2 = compptr2->quant_table;
for (k = 0; k < DCTSIZE2; k++) {
if (qtblptr1->quantval[k] != qtblptr2->quantval[k]) {
if (trim)
requant_comp(dropinfo, compptr2, drop_coef_arrays[ci], qtblptr1);
else {
qtblptr3 = dstinfo->quant_tbl_ptrs[compptr1->quant_tbl_no];
for (k = 0; k < DCTSIZE2; k++)
if (qtblptr1->quantval[k] != qtblptr2->quantval[k])
qtblptr3->quantval[k] =
largest_common_denominator(qtblptr1->quantval[k],
qtblptr2->quantval[k]);
dequant_comp(srcinfo, compptr1, src_coef_arrays[ci], qtblptr3);
dequant_comp(dropinfo, compptr2, drop_coef_arrays[ci], qtblptr3);
}
break;
}
}
}
}
LOCAL(void)
do_drop(j_decompress_ptr srcinfo, j_compress_ptr dstinfo,
JDIMENSION x_crop_offset, JDIMENSION y_crop_offset,
jvirt_barray_ptr *src_coef_arrays,
j_decompress_ptr dropinfo, jvirt_barray_ptr *drop_coef_arrays,
JDIMENSION drop_width, JDIMENSION drop_height)
/* Drop (insert) the contents of another image into the source image. If the
* number of components in the drop image is smaller than the number of
* components in the destination image, then we fill in the remaining
* components with zero. This allows for dropping the contents of grayscale
* images into (arbitrarily sampled) color images.
*/
{
JDIMENSION comp_width, comp_height;
JDIMENSION blk_y, x_drop_blocks, y_drop_blocks;
int ci, offset_y;
JBLOCKARRAY src_buffer, dst_buffer;
jpeg_component_info *compptr;
for (ci = 0; ci < dstinfo->num_components; ci++) {
compptr = dstinfo->comp_info + ci;
comp_width = drop_width * compptr->h_samp_factor;
comp_height = drop_height * compptr->v_samp_factor;
x_drop_blocks = x_crop_offset * compptr->h_samp_factor;
y_drop_blocks = y_crop_offset * compptr->v_samp_factor;
for (blk_y = 0; blk_y < comp_height; blk_y += compptr->v_samp_factor) {
dst_buffer = (*srcinfo->mem->access_virt_barray)
((j_common_ptr)srcinfo, src_coef_arrays[ci], blk_y + y_drop_blocks,
(JDIMENSION)compptr->v_samp_factor, TRUE);
if (ci < dropinfo->num_components) {
src_buffer = (*dropinfo->mem->access_virt_barray)
((j_common_ptr)dropinfo, drop_coef_arrays[ci], blk_y,
(JDIMENSION)compptr->v_samp_factor, FALSE);
for (offset_y = 0; offset_y < compptr->v_samp_factor; offset_y++) {
jcopy_block_row(src_buffer[offset_y],
dst_buffer[offset_y] + x_drop_blocks, comp_width);
}
} else {
for (offset_y = 0; offset_y < compptr->v_samp_factor; offset_y++) {
MEMZERO(dst_buffer[offset_y] + x_drop_blocks,
comp_width * sizeof(JBLOCK));
}
}
}
}
}
LOCAL(void)
do_crop(j_decompress_ptr srcinfo, j_compress_ptr dstinfo,
JDIMENSION x_crop_offset, JDIMENSION y_crop_offset,
@@ -113,13 +296,422 @@ do_crop(j_decompress_ptr srcinfo, j_compress_ptr dstinfo,
((j_common_ptr)srcinfo, dst_coef_arrays[ci], dst_blk_y,
(JDIMENSION)compptr->v_samp_factor, TRUE);
src_buffer = (*srcinfo->mem->access_virt_barray)
((j_common_ptr)srcinfo, src_coef_arrays[ci],
dst_blk_y + y_crop_blocks,
((j_common_ptr)srcinfo, src_coef_arrays[ci], dst_blk_y + y_crop_blocks,
(JDIMENSION)compptr->v_samp_factor, FALSE);
for (offset_y = 0; offset_y < compptr->v_samp_factor; offset_y++) {
jcopy_block_row(src_buffer[offset_y] + x_crop_blocks,
dst_buffer[offset_y],
compptr->width_in_blocks);
dst_buffer[offset_y], compptr->width_in_blocks);
}
}
}
}
LOCAL(void)
do_crop_ext_zero(j_decompress_ptr srcinfo, j_compress_ptr dstinfo,
JDIMENSION x_crop_offset, JDIMENSION y_crop_offset,
jvirt_barray_ptr *src_coef_arrays,
jvirt_barray_ptr *dst_coef_arrays)
/* Crop. This is only used when no rotate/flip is requested with the crop.
* Extension: If the destination size is larger than the source, we fill in the
* expanded region with zero (neutral gray). Note that we also have to zero
* partial iMCUs at the right and bottom edge of the source image area in this
* case.
*/
{
JDIMENSION MCU_cols, MCU_rows, comp_width, comp_height;
JDIMENSION dst_blk_y, x_crop_blocks, y_crop_blocks;
int ci, offset_y;
JBLOCKARRAY src_buffer, dst_buffer;
jpeg_component_info *compptr;
MCU_cols = srcinfo->output_width /
(dstinfo->max_h_samp_factor * dstinfo_min_DCT_h_scaled_size);
MCU_rows = srcinfo->output_height /
(dstinfo->max_v_samp_factor * dstinfo_min_DCT_v_scaled_size);
for (ci = 0; ci < dstinfo->num_components; ci++) {
compptr = dstinfo->comp_info + ci;
comp_width = MCU_cols * compptr->h_samp_factor;
comp_height = MCU_rows * compptr->v_samp_factor;
x_crop_blocks = x_crop_offset * compptr->h_samp_factor;
y_crop_blocks = y_crop_offset * compptr->v_samp_factor;
for (dst_blk_y = 0; dst_blk_y < compptr->height_in_blocks;
dst_blk_y += compptr->v_samp_factor) {
dst_buffer = (*srcinfo->mem->access_virt_barray)
((j_common_ptr)srcinfo, dst_coef_arrays[ci], dst_blk_y,
(JDIMENSION)compptr->v_samp_factor, TRUE);
if (dstinfo->_jpeg_height > srcinfo->output_height) {
if (dst_blk_y < y_crop_blocks ||
dst_blk_y >= y_crop_blocks + comp_height) {
for (offset_y = 0; offset_y < compptr->v_samp_factor; offset_y++) {
MEMZERO(dst_buffer[offset_y],
compptr->width_in_blocks * sizeof(JBLOCK));
}
continue;
}
src_buffer = (*srcinfo->mem->access_virt_barray)
((j_common_ptr)srcinfo, src_coef_arrays[ci],
dst_blk_y - y_crop_blocks, (JDIMENSION)compptr->v_samp_factor,
FALSE);
} else {
src_buffer = (*srcinfo->mem->access_virt_barray)
((j_common_ptr)srcinfo, src_coef_arrays[ci],
dst_blk_y + y_crop_blocks, (JDIMENSION)compptr->v_samp_factor,
FALSE);
}
for (offset_y = 0; offset_y < compptr->v_samp_factor; offset_y++) {
if (dstinfo->_jpeg_width > srcinfo->output_width) {
if (x_crop_blocks > 0) {
MEMZERO(dst_buffer[offset_y], x_crop_blocks * sizeof(JBLOCK));
}
jcopy_block_row(src_buffer[offset_y],
dst_buffer[offset_y] + x_crop_blocks, comp_width);
if (compptr->width_in_blocks > x_crop_blocks + comp_width) {
MEMZERO(dst_buffer[offset_y] + x_crop_blocks + comp_width,
(compptr->width_in_blocks - x_crop_blocks - comp_width) *
sizeof(JBLOCK));
}
} else {
jcopy_block_row(src_buffer[offset_y] + x_crop_blocks,
dst_buffer[offset_y], compptr->width_in_blocks);
}
}
}
}
}
LOCAL(void)
do_crop_ext_flat(j_decompress_ptr srcinfo, j_compress_ptr dstinfo,
JDIMENSION x_crop_offset, JDIMENSION y_crop_offset,
jvirt_barray_ptr *src_coef_arrays,
jvirt_barray_ptr *dst_coef_arrays)
/* Crop. This is only used when no rotate/flip is requested with the crop.
* Extension: The destination width is larger than the source, and we fill in
* the expanded region with the DC coefficient of the adjacent block. Note
* that we also have to fill partial iMCUs at the right and bottom edge of the
* source image area in this case.
*/
{
JDIMENSION MCU_cols, MCU_rows, comp_width, comp_height;
JDIMENSION dst_blk_x, dst_blk_y, x_crop_blocks, y_crop_blocks;
int ci, offset_y;
JCOEF dc;
JBLOCKARRAY src_buffer, dst_buffer;
jpeg_component_info *compptr;
MCU_cols = srcinfo->output_width /
(dstinfo->max_h_samp_factor * dstinfo_min_DCT_h_scaled_size);
MCU_rows = srcinfo->output_height /
(dstinfo->max_v_samp_factor * dstinfo_min_DCT_v_scaled_size);
for (ci = 0; ci < dstinfo->num_components; ci++) {
compptr = dstinfo->comp_info + ci;
comp_width = MCU_cols * compptr->h_samp_factor;
comp_height = MCU_rows * compptr->v_samp_factor;
x_crop_blocks = x_crop_offset * compptr->h_samp_factor;
y_crop_blocks = y_crop_offset * compptr->v_samp_factor;
for (dst_blk_y = 0; dst_blk_y < compptr->height_in_blocks;
dst_blk_y += compptr->v_samp_factor) {
dst_buffer = (*srcinfo->mem->access_virt_barray)
((j_common_ptr)srcinfo, dst_coef_arrays[ci], dst_blk_y,
(JDIMENSION)compptr->v_samp_factor, TRUE);
if (dstinfo->_jpeg_height > srcinfo->output_height) {
if (dst_blk_y < y_crop_blocks ||
dst_blk_y >= y_crop_blocks + comp_height) {
for (offset_y = 0; offset_y < compptr->v_samp_factor; offset_y++) {
MEMZERO(dst_buffer[offset_y],
compptr->width_in_blocks * sizeof(JBLOCK));
}
continue;
}
src_buffer = (*srcinfo->mem->access_virt_barray)
((j_common_ptr)srcinfo, src_coef_arrays[ci],
dst_blk_y - y_crop_blocks, (JDIMENSION)compptr->v_samp_factor,
FALSE);
} else {
src_buffer = (*srcinfo->mem->access_virt_barray)
((j_common_ptr)srcinfo, src_coef_arrays[ci],
dst_blk_y + y_crop_blocks, (JDIMENSION)compptr->v_samp_factor,
FALSE);
}
for (offset_y = 0; offset_y < compptr->v_samp_factor; offset_y++) {
if (x_crop_blocks > 0) {
MEMZERO(dst_buffer[offset_y], x_crop_blocks * sizeof(JBLOCK));
dc = src_buffer[offset_y][0][0];
for (dst_blk_x = 0; dst_blk_x < x_crop_blocks; dst_blk_x++) {
dst_buffer[offset_y][dst_blk_x][0] = dc;
}
}
jcopy_block_row(src_buffer[offset_y],
dst_buffer[offset_y] + x_crop_blocks, comp_width);
if (compptr->width_in_blocks > x_crop_blocks + comp_width) {
MEMZERO(dst_buffer[offset_y] + x_crop_blocks + comp_width,
(compptr->width_in_blocks - x_crop_blocks - comp_width) *
sizeof(JBLOCK));
dc = src_buffer[offset_y][comp_width - 1][0];
for (dst_blk_x = x_crop_blocks + comp_width;
dst_blk_x < compptr->width_in_blocks; dst_blk_x++) {
dst_buffer[offset_y][dst_blk_x][0] = dc;
}
}
}
}
}
}
LOCAL(void)
do_crop_ext_reflect(j_decompress_ptr srcinfo, j_compress_ptr dstinfo,
JDIMENSION x_crop_offset, JDIMENSION y_crop_offset,
jvirt_barray_ptr *src_coef_arrays,
jvirt_barray_ptr *dst_coef_arrays)
/* Crop. This is only used when no rotate/flip is requested with the crop.
* Extension: The destination width is larger than the source, and we fill in
* the expanded region with repeated reflections of the source image. Note
* that we also have to fill partial iMCUs at the right and bottom edge of the
* source image area in this case.
*/
{
JDIMENSION MCU_cols, MCU_rows, comp_width, comp_height, src_blk_x;
JDIMENSION dst_blk_x, dst_blk_y, x_crop_blocks, y_crop_blocks;
int ci, k, offset_y;
JBLOCKARRAY src_buffer, dst_buffer;
JBLOCKROW src_row_ptr, dst_row_ptr;
JCOEFPTR src_ptr, dst_ptr;
jpeg_component_info *compptr;
MCU_cols = srcinfo->output_width /
(dstinfo->max_h_samp_factor * dstinfo_min_DCT_h_scaled_size);
MCU_rows = srcinfo->output_height /
(dstinfo->max_v_samp_factor * dstinfo_min_DCT_v_scaled_size);
for (ci = 0; ci < dstinfo->num_components; ci++) {
compptr = dstinfo->comp_info + ci;
comp_width = MCU_cols * compptr->h_samp_factor;
comp_height = MCU_rows * compptr->v_samp_factor;
x_crop_blocks = x_crop_offset * compptr->h_samp_factor;
y_crop_blocks = y_crop_offset * compptr->v_samp_factor;
for (dst_blk_y = 0; dst_blk_y < compptr->height_in_blocks;
dst_blk_y += compptr->v_samp_factor) {
dst_buffer = (*srcinfo->mem->access_virt_barray)
((j_common_ptr)srcinfo, dst_coef_arrays[ci], dst_blk_y,
(JDIMENSION)compptr->v_samp_factor, TRUE);
if (dstinfo->_jpeg_height > srcinfo->output_height) {
if (dst_blk_y < y_crop_blocks ||
dst_blk_y >= y_crop_blocks + comp_height) {
for (offset_y = 0; offset_y < compptr->v_samp_factor; offset_y++) {
MEMZERO(dst_buffer[offset_y],
compptr->width_in_blocks * sizeof(JBLOCK));
}
continue;
}
src_buffer = (*srcinfo->mem->access_virt_barray)
((j_common_ptr)srcinfo, src_coef_arrays[ci],
dst_blk_y - y_crop_blocks, (JDIMENSION)compptr->v_samp_factor,
FALSE);
} else {
src_buffer = (*srcinfo->mem->access_virt_barray)
((j_common_ptr)srcinfo, src_coef_arrays[ci],
dst_blk_y + y_crop_blocks, (JDIMENSION)compptr->v_samp_factor,
FALSE);
}
for (offset_y = 0; offset_y < compptr->v_samp_factor; offset_y++) {
/* Copy source region */
jcopy_block_row(src_buffer[offset_y],
dst_buffer[offset_y] + x_crop_blocks, comp_width);
if (x_crop_blocks > 0) {
/* Reflect to left */
dst_row_ptr = dst_buffer[offset_y] + x_crop_blocks;
for (dst_blk_x = x_crop_blocks; dst_blk_x > 0;) {
src_row_ptr = dst_row_ptr; /* (re)set axis of reflection */
for (src_blk_x = comp_width; src_blk_x > 0 && dst_blk_x > 0;
src_blk_x--, dst_blk_x--) {
dst_ptr = *(--dst_row_ptr); /* destination goes left */
src_ptr = *src_row_ptr++; /* source goes right */
/* This unrolled loop doesn't need to know which row it's on. */
for (k = 0; k < DCTSIZE2; k += 2) {
*dst_ptr++ = *src_ptr++; /* copy even column */
*dst_ptr++ = -(*src_ptr++); /* copy odd column with sign
change */
}
}
}
}
if (compptr->width_in_blocks > x_crop_blocks + comp_width) {
/* Reflect to right */
dst_row_ptr = dst_buffer[offset_y] + x_crop_blocks + comp_width;
for (dst_blk_x = compptr->width_in_blocks - x_crop_blocks - comp_width;
dst_blk_x > 0;) {
src_row_ptr = dst_row_ptr; /* (re)set axis of reflection */
for (src_blk_x = comp_width; src_blk_x > 0 && dst_blk_x > 0;
src_blk_x--, dst_blk_x--) {
dst_ptr = *dst_row_ptr++; /* destination goes right */
src_ptr = *(--src_row_ptr); /* source goes left */
/* This unrolled loop doesn't need to know which row it's on. */
for (k = 0; k < DCTSIZE2; k += 2) {
*dst_ptr++ = *src_ptr++; /* copy even column */
*dst_ptr++ = -(*src_ptr++); /* copy odd column with sign
change */
}
}
}
}
}
}
}
}
LOCAL(void)
do_wipe(j_decompress_ptr srcinfo, j_compress_ptr dstinfo,
JDIMENSION x_crop_offset, JDIMENSION y_crop_offset,
jvirt_barray_ptr *src_coef_arrays,
JDIMENSION drop_width, JDIMENSION drop_height)
/* Wipe - discard image contents of specified region and fill with zero
* (neutral gray)
*/
{
JDIMENSION x_wipe_blocks, wipe_width;
JDIMENSION y_wipe_blocks, wipe_bottom;
int ci, offset_y;
JBLOCKARRAY buffer;
jpeg_component_info *compptr;
for (ci = 0; ci < dstinfo->num_components; ci++) {
compptr = dstinfo->comp_info + ci;
x_wipe_blocks = x_crop_offset * compptr->h_samp_factor;
wipe_width = drop_width * compptr->h_samp_factor;
y_wipe_blocks = y_crop_offset * compptr->v_samp_factor;
wipe_bottom = drop_height * compptr->v_samp_factor + y_wipe_blocks;
for (; y_wipe_blocks < wipe_bottom;
y_wipe_blocks += compptr->v_samp_factor) {
buffer = (*srcinfo->mem->access_virt_barray)
((j_common_ptr)srcinfo, src_coef_arrays[ci], y_wipe_blocks,
(JDIMENSION)compptr->v_samp_factor, TRUE);
for (offset_y = 0; offset_y < compptr->v_samp_factor; offset_y++) {
MEMZERO(buffer[offset_y] + x_wipe_blocks, wipe_width * sizeof(JBLOCK));
}
}
}
}
LOCAL(void)
do_flatten(j_decompress_ptr srcinfo, j_compress_ptr dstinfo,
JDIMENSION x_crop_offset, JDIMENSION y_crop_offset,
jvirt_barray_ptr *src_coef_arrays,
JDIMENSION drop_width, JDIMENSION drop_height)
/* Flatten - discard image contents of specified region, similarly to wipe,
* but fill with the average of adjacent blocks instead of zero.
*/
{
JDIMENSION x_wipe_blocks, wipe_width, wipe_right;
JDIMENSION y_wipe_blocks, wipe_bottom, blk_x;
int ci, offset_y, dc_left_value, dc_right_value, average;
JBLOCKARRAY buffer;
jpeg_component_info *compptr;
for (ci = 0; ci < dstinfo->num_components; ci++) {
compptr = dstinfo->comp_info + ci;
x_wipe_blocks = x_crop_offset * compptr->h_samp_factor;
wipe_width = drop_width * compptr->h_samp_factor;
wipe_right = wipe_width + x_wipe_blocks;
y_wipe_blocks = y_crop_offset * compptr->v_samp_factor;
wipe_bottom = drop_height * compptr->v_samp_factor + y_wipe_blocks;
for (; y_wipe_blocks < wipe_bottom;
y_wipe_blocks += compptr->v_samp_factor) {
buffer = (*srcinfo->mem->access_virt_barray)
((j_common_ptr)srcinfo, src_coef_arrays[ci], y_wipe_blocks,
(JDIMENSION)compptr->v_samp_factor, TRUE);
for (offset_y = 0; offset_y < compptr->v_samp_factor; offset_y++) {
MEMZERO(buffer[offset_y] + x_wipe_blocks, wipe_width * sizeof(JBLOCK));
if (x_wipe_blocks > 0) {
dc_left_value = buffer[offset_y][x_wipe_blocks - 1][0];
if (wipe_right < compptr->width_in_blocks) {
dc_right_value = buffer[offset_y][wipe_right][0];
average = (dc_left_value + dc_right_value) >> 1;
} else {
average = dc_left_value;
}
} else if (wipe_right < compptr->width_in_blocks) {
average = buffer[offset_y][wipe_right][0];
} else continue;
for (blk_x = x_wipe_blocks; blk_x < wipe_right; blk_x++) {
buffer[offset_y][blk_x][0] = (JCOEF)average;
}
}
}
}
}
LOCAL(void)
do_reflect(j_decompress_ptr srcinfo, j_compress_ptr dstinfo,
JDIMENSION x_crop_offset, jvirt_barray_ptr *src_coef_arrays,
JDIMENSION drop_width, JDIMENSION drop_height)
/* Reflect - discard image contents of specified region, similarly to wipe,
* but fill with repeated reflections of the outside region instead of zero.
* NB: y_crop_offset is assumed to be zero.
*/
{
JDIMENSION x_wipe_blocks, wipe_width;
JDIMENSION y_wipe_blocks, wipe_bottom;
JDIMENSION src_blk_x, dst_blk_x;
int ci, k, offset_y;
JBLOCKARRAY buffer;
JBLOCKROW src_row_ptr, dst_row_ptr;
JCOEFPTR src_ptr, dst_ptr;
jpeg_component_info *compptr;
for (ci = 0; ci < dstinfo->num_components; ci++) {
compptr = dstinfo->comp_info + ci;
x_wipe_blocks = x_crop_offset * compptr->h_samp_factor;
wipe_width = drop_width * compptr->h_samp_factor;
wipe_bottom = drop_height * compptr->v_samp_factor;
for (y_wipe_blocks = 0; y_wipe_blocks < wipe_bottom;
y_wipe_blocks += compptr->v_samp_factor) {
buffer = (*srcinfo->mem->access_virt_barray)
((j_common_ptr)srcinfo, src_coef_arrays[ci], y_wipe_blocks,
(JDIMENSION)compptr->v_samp_factor, TRUE);
for (offset_y = 0; offset_y < compptr->v_samp_factor; offset_y++) {
if (x_wipe_blocks > 0) {
/* Reflect from left */
dst_row_ptr = buffer[offset_y] + x_wipe_blocks;
for (dst_blk_x = wipe_width; dst_blk_x > 0;) {
src_row_ptr = dst_row_ptr; /* (re)set axis of reflection */
for (src_blk_x = x_wipe_blocks;
src_blk_x > 0 && dst_blk_x > 0; src_blk_x--, dst_blk_x--) {
dst_ptr = *dst_row_ptr++; /* destination goes right */
src_ptr = *(--src_row_ptr); /* source goes left */
/* this unrolled loop doesn't need to know which row it's on... */
for (k = 0; k < DCTSIZE2; k += 2) {
*dst_ptr++ = *src_ptr++; /* copy even column */
*dst_ptr++ = -(*src_ptr++); /* copy odd column with sign change */
}
}
}
} else if (compptr->width_in_blocks > x_wipe_blocks + wipe_width) {
/* Reflect from right */
dst_row_ptr = buffer[offset_y] + x_wipe_blocks + wipe_width;
for (dst_blk_x = wipe_width; dst_blk_x > 0;) {
src_row_ptr = dst_row_ptr; /* (re)set axis of reflection */
src_blk_x = compptr->width_in_blocks - x_wipe_blocks - wipe_width;
for (; src_blk_x > 0 && dst_blk_x > 0; src_blk_x--, dst_blk_x--) {
dst_ptr = *(--dst_row_ptr); /* destination goes left */
src_ptr = *src_row_ptr++; /* source goes right */
/* this unrolled loop doesn't need to know which row it's on... */
for (k = 0; k < DCTSIZE2; k += 2) {
*dst_ptr++ = *src_ptr++; /* copy even column */
*dst_ptr++ = -(*src_ptr++); /* copy odd column with sign change */
}
}
}
} else {
MEMZERO(buffer[offset_y] + x_wipe_blocks,
wipe_width * sizeof(JBLOCK));
}
}
}
}
@@ -239,7 +831,7 @@ do_flip_h(j_decompress_ptr srcinfo, j_compress_ptr dstinfo,
/* this unrolled loop doesn't need to know which row it's on... */
for (k = 0; k < DCTSIZE2; k += 2) {
*dst_ptr++ = *src_ptr++; /* copy even column */
*dst_ptr++ = - *src_ptr++; /* copy odd column with sign change */
*dst_ptr++ = -(*src_ptr++); /* copy odd column with sign change */
}
} else {
/* Copy last partial block(s) verbatim */
@@ -318,7 +910,7 @@ do_flip_v(j_decompress_ptr srcinfo, j_compress_ptr dstinfo,
*dst_ptr++ = *src_ptr++;
/* copy odd row with sign change */
for (j = 0; j < DCTSIZE; j++)
*dst_ptr++ = - *src_ptr++;
*dst_ptr++ = -(*src_ptr++);
}
}
} else {
@@ -599,11 +1191,11 @@ do_rot_180(j_decompress_ptr srcinfo, j_compress_ptr dstinfo,
/* For even row, negate every odd column. */
for (j = 0; j < DCTSIZE; j += 2) {
*dst_ptr++ = *src_ptr++;
*dst_ptr++ = - *src_ptr++;
*dst_ptr++ = -(*src_ptr++);
}
/* For odd row, negate every even column. */
for (j = 0; j < DCTSIZE; j += 2) {
*dst_ptr++ = - *src_ptr++;
*dst_ptr++ = -(*src_ptr++);
*dst_ptr++ = *src_ptr++;
}
}
@@ -614,7 +1206,7 @@ do_rot_180(j_decompress_ptr srcinfo, j_compress_ptr dstinfo,
for (j = 0; j < DCTSIZE; j++)
*dst_ptr++ = *src_ptr++;
for (j = 0; j < DCTSIZE; j++)
*dst_ptr++ = - *src_ptr++;
*dst_ptr++ = -(*src_ptr++);
}
}
}
@@ -630,7 +1222,7 @@ do_rot_180(j_decompress_ptr srcinfo, j_compress_ptr dstinfo,
src_row_ptr[comp_width - x_crop_blocks - dst_blk_x - 1];
for (i = 0; i < DCTSIZE2; i += 2) {
*dst_ptr++ = *src_ptr++;
*dst_ptr++ = - *src_ptr++;
*dst_ptr++ = -(*src_ptr++);
}
} else {
/* Any remaining right-edge blocks are only copied. */
@@ -786,7 +1378,7 @@ jt_read_integer(const char **strptr, JDIMENSION *result)
* The routine returns TRUE if the spec string is valid, FALSE if not.
*
* The crop spec string should have the format
* <width>[f]x<height>[f]{+-}<xoffset>{+-}<yoffset>
* <width>[{fr}]x<height>[{fr}]{+-}<xoffset>{+-}<yoffset>
* where width, height, xoffset, and yoffset are unsigned integers.
* Each of the elements can be omitted to indicate a default value.
* (A weakness of this style is that it is not possible to omit xoffset
@@ -811,6 +1403,9 @@ jtransform_parse_crop_spec(jpeg_transform_info *info, const char *spec)
if (*spec == 'f' || *spec == 'F') {
spec++;
info->crop_width_set = JCROP_FORCE;
} else if (*spec == 'r' || *spec == 'R') {
spec++;
info->crop_width_set = JCROP_REFLECT;
} else
info->crop_width_set = JCROP_POS;
}
@@ -822,6 +1417,9 @@ jtransform_parse_crop_spec(jpeg_transform_info *info, const char *spec)
if (*spec == 'f' || *spec == 'F') {
spec++;
info->crop_height_set = JCROP_FORCE;
} else if (*spec == 'r' || *spec == 'R') {
spec++;
info->crop_height_set = JCROP_REFLECT;
} else
info->crop_height_set = JCROP_POS;
}
@@ -896,10 +1494,10 @@ jtransform_request_workspace(j_decompress_ptr srcinfo,
jvirt_barray_ptr *coef_arrays;
boolean need_workspace, transpose_it;
jpeg_component_info *compptr;
JDIMENSION xoffset, yoffset;
JDIMENSION xoffset, yoffset, dtemp;
JDIMENSION width_in_iMCUs, height_in_iMCUs;
JDIMENSION width_in_blocks, height_in_blocks;
int ci, h_samp_factor, v_samp_factor;
int itemp, ci, h_samp_factor, v_samp_factor;
/* Determine number of components in output image */
if (info->force_grayscale &&
@@ -985,39 +1583,129 @@ jtransform_request_workspace(j_decompress_ptr srcinfo,
info->crop_xoffset = 0; /* default to +0 */
if (info->crop_yoffset_set == JCROP_UNSET)
info->crop_yoffset = 0; /* default to +0 */
if (info->crop_xoffset >= info->output_width ||
info->crop_yoffset >= info->output_height)
ERREXIT(srcinfo, JERR_BAD_CROP_SPEC);
if (info->crop_width_set == JCROP_UNSET)
if (info->crop_width_set == JCROP_UNSET) {
if (info->crop_xoffset >= info->output_width)
ERREXIT(srcinfo, JERR_BAD_CROP_SPEC);
info->crop_width = info->output_width - info->crop_xoffset;
if (info->crop_height_set == JCROP_UNSET)
} else {
/* Check for crop extension */
if (info->crop_width > info->output_width) {
/* Crop extension does not work when transforming! */
if (info->transform != JXFORM_NONE ||
info->crop_xoffset >= info->crop_width ||
info->crop_xoffset > info->crop_width - info->output_width)
ERREXIT(srcinfo, JERR_BAD_CROP_SPEC);
} else {
if (info->crop_xoffset >= info->output_width ||
info->crop_width <= 0 ||
info->crop_xoffset > info->output_width - info->crop_width)
ERREXIT(srcinfo, JERR_BAD_CROP_SPEC);
}
}
if (info->crop_height_set == JCROP_UNSET) {
if (info->crop_yoffset >= info->output_height)
ERREXIT(srcinfo, JERR_BAD_CROP_SPEC);
info->crop_height = info->output_height - info->crop_yoffset;
/* Ensure parameters are valid */
if (info->crop_width <= 0 || info->crop_width > info->output_width ||
info->crop_height <= 0 || info->crop_height > info->output_height ||
info->crop_xoffset > info->output_width - info->crop_width ||
info->crop_yoffset > info->output_height - info->crop_height)
ERREXIT(srcinfo, JERR_BAD_CROP_SPEC);
} else {
/* Check for crop extension */
if (info->crop_height > info->output_height) {
/* Crop extension does not work when transforming! */
if (info->transform != JXFORM_NONE ||
info->crop_yoffset >= info->crop_height ||
info->crop_yoffset > info->crop_height - info->output_height)
ERREXIT(srcinfo, JERR_BAD_CROP_SPEC);
} else {
if (info->crop_yoffset >= info->output_height ||
info->crop_height <= 0 ||
info->crop_yoffset > info->output_height - info->crop_height)
ERREXIT(srcinfo, JERR_BAD_CROP_SPEC);
}
}
/* Convert negative crop offsets into regular offsets */
if (info->crop_xoffset_set == JCROP_NEG)
xoffset = info->output_width - info->crop_width - info->crop_xoffset;
else
if (info->crop_xoffset_set != JCROP_NEG)
xoffset = info->crop_xoffset;
if (info->crop_yoffset_set == JCROP_NEG)
yoffset = info->output_height - info->crop_height - info->crop_yoffset;
else if (info->crop_width > info->output_width) /* crop extension */
xoffset = info->crop_width - info->output_width - info->crop_xoffset;
else
xoffset = info->output_width - info->crop_width - info->crop_xoffset;
if (info->crop_yoffset_set != JCROP_NEG)
yoffset = info->crop_yoffset;
else if (info->crop_height > info->output_height) /* crop extension */
yoffset = info->crop_height - info->output_height - info->crop_yoffset;
else
yoffset = info->output_height - info->crop_height - info->crop_yoffset;
/* Now adjust so that upper left corner falls at an iMCU boundary */
if (info->crop_width_set == JCROP_FORCE)
info->output_width = info->crop_width;
else
info->output_width =
info->crop_width + (xoffset % info->iMCU_sample_width);
if (info->crop_height_set == JCROP_FORCE)
info->output_height = info->crop_height;
else
info->output_height =
info->crop_height + (yoffset % info->iMCU_sample_height);
switch (info->transform) {
case JXFORM_DROP:
/* Ensure the effective drop region will not exceed the requested */
itemp = info->iMCU_sample_width;
dtemp = itemp - 1 - ((xoffset + itemp - 1) % itemp);
xoffset += dtemp;
if (info->crop_width <= dtemp)
info->drop_width = 0;
else if (xoffset + info->crop_width - dtemp == info->output_width)
/* Matching right edge: include partial iMCU */
info->drop_width = (info->crop_width - dtemp + itemp - 1) / itemp;
else
info->drop_width = (info->crop_width - dtemp) / itemp;
itemp = info->iMCU_sample_height;
dtemp = itemp - 1 - ((yoffset + itemp - 1) % itemp);
yoffset += dtemp;
if (info->crop_height <= dtemp)
info->drop_height = 0;
else if (yoffset + info->crop_height - dtemp == info->output_height)
/* Matching bottom edge: include partial iMCU */
info->drop_height = (info->crop_height - dtemp + itemp - 1) / itemp;
else
info->drop_height = (info->crop_height - dtemp) / itemp;
/* Check if sampling factors match for dropping */
if (info->drop_width != 0 && info->drop_height != 0)
for (ci = 0; ci < info->num_components &&
ci < info->drop_ptr->num_components; ci++) {
if (info->drop_ptr->comp_info[ci].h_samp_factor *
srcinfo->max_h_samp_factor !=
srcinfo->comp_info[ci].h_samp_factor *
info->drop_ptr->max_h_samp_factor)
ERREXIT6(srcinfo, JERR_BAD_DROP_SAMPLING, ci,
info->drop_ptr->comp_info[ci].h_samp_factor,
info->drop_ptr->max_h_samp_factor,
srcinfo->comp_info[ci].h_samp_factor,
srcinfo->max_h_samp_factor, 'h');
if (info->drop_ptr->comp_info[ci].v_samp_factor *
srcinfo->max_v_samp_factor !=
srcinfo->comp_info[ci].v_samp_factor *
info->drop_ptr->max_v_samp_factor)
ERREXIT6(srcinfo, JERR_BAD_DROP_SAMPLING, ci,
info->drop_ptr->comp_info[ci].v_samp_factor,
info->drop_ptr->max_v_samp_factor,
srcinfo->comp_info[ci].v_samp_factor,
srcinfo->max_v_samp_factor, 'v');
}
break;
case JXFORM_WIPE:
/* Ensure the effective wipe region will cover the requested */
info->drop_width = (JDIMENSION)jdiv_round_up
((long)(info->crop_width + (xoffset % info->iMCU_sample_width)),
(long)info->iMCU_sample_width);
info->drop_height = (JDIMENSION)jdiv_round_up
((long)(info->crop_height + (yoffset % info->iMCU_sample_height)),
(long)info->iMCU_sample_height);
break;
default:
/* Ensure the effective crop region will cover the requested */
if (info->crop_width_set == JCROP_FORCE ||
info->crop_width > info->output_width)
info->output_width = info->crop_width;
else
info->output_width =
info->crop_width + (xoffset % info->iMCU_sample_width);
if (info->crop_height_set == JCROP_FORCE ||
info->crop_height > info->output_height)
info->output_height = info->crop_height;
else
info->output_height =
info->crop_height + (yoffset % info->iMCU_sample_height);
}
/* Save x/y offsets measured in iMCUs */
info->x_crop_offset = xoffset / info->iMCU_sample_width;
info->y_crop_offset = yoffset / info->iMCU_sample_height;
@@ -1033,7 +1721,9 @@ jtransform_request_workspace(j_decompress_ptr srcinfo,
transpose_it = FALSE;
switch (info->transform) {
case JXFORM_NONE:
if (info->x_crop_offset != 0 || info->y_crop_offset != 0)
if (info->x_crop_offset != 0 || info->y_crop_offset != 0 ||
info->output_width > srcinfo->output_width ||
info->output_height > srcinfo->output_height)
need_workspace = TRUE;
/* No workspace needed if neither cropping nor transforming */
break;
@@ -1087,6 +1777,10 @@ jtransform_request_workspace(j_decompress_ptr srcinfo,
need_workspace = TRUE;
transpose_it = TRUE;
break;
case JXFORM_WIPE:
break;
case JXFORM_DROP:
break;
}
/* Allocate workspace if needed.
@@ -1387,7 +2081,7 @@ jtransform_adjust_parameters(j_decompress_ptr srcinfo, j_compress_ptr dstinfo,
dstinfo->jpeg_height = info->output_height;
#endif
/* Transpose destination image parameters */
/* Transpose destination image parameters, adjust quantization */
switch (info->transform) {
case JXFORM_TRANSPOSE:
case JXFORM_TRANSVERSE:
@@ -1399,6 +2093,12 @@ jtransform_adjust_parameters(j_decompress_ptr srcinfo, j_compress_ptr dstinfo,
#endif
transpose_critical_parameters(dstinfo);
break;
case JXFORM_DROP:
if (info->drop_width != 0 && info->drop_height != 0)
adjust_quant(srcinfo, src_coef_arrays,
info->drop_ptr, info->drop_coef_arrays,
info->trim, dstinfo);
break;
default:
#if JPEG_LIB_VERSION < 80
dstinfo->image_width = info->output_width;
@@ -1465,7 +2165,23 @@ jtransform_execute_transform(j_decompress_ptr srcinfo, j_compress_ptr dstinfo,
*/
switch (info->transform) {
case JXFORM_NONE:
if (info->x_crop_offset != 0 || info->y_crop_offset != 0)
if (info->output_width > srcinfo->output_width ||
info->output_height > srcinfo->output_height) {
if (info->output_width > srcinfo->output_width &&
info->crop_width_set == JCROP_REFLECT)
do_crop_ext_reflect(srcinfo, dstinfo,
info->x_crop_offset, info->y_crop_offset,
src_coef_arrays, dst_coef_arrays);
else if (info->output_width > srcinfo->output_width &&
info->crop_width_set == JCROP_FORCE)
do_crop_ext_flat(srcinfo, dstinfo,
info->x_crop_offset, info->y_crop_offset,
src_coef_arrays, dst_coef_arrays);
else
do_crop_ext_zero(srcinfo, dstinfo,
info->x_crop_offset, info->y_crop_offset,
src_coef_arrays, dst_coef_arrays);
} else if (info->x_crop_offset != 0 || info->y_crop_offset != 0)
do_crop(srcinfo, dstinfo, info->x_crop_offset, info->y_crop_offset,
src_coef_arrays, dst_coef_arrays);
break;
@@ -1501,6 +2217,30 @@ jtransform_execute_transform(j_decompress_ptr srcinfo, j_compress_ptr dstinfo,
do_rot_270(srcinfo, dstinfo, info->x_crop_offset, info->y_crop_offset,
src_coef_arrays, dst_coef_arrays);
break;
case JXFORM_WIPE:
if (info->crop_width_set == JCROP_REFLECT &&
info->y_crop_offset == 0 && info->drop_height ==
(JDIMENSION)jdiv_round_up
((long)info->output_height, (long)info->iMCU_sample_height) &&
(info->x_crop_offset == 0 ||
info->x_crop_offset + info->drop_width ==
(JDIMENSION)jdiv_round_up
((long)info->output_width, (long)info->iMCU_sample_width)))
do_reflect(srcinfo, dstinfo, info->x_crop_offset,
src_coef_arrays, info->drop_width, info->drop_height);
else if (info->crop_width_set == JCROP_FORCE)
do_flatten(srcinfo, dstinfo, info->x_crop_offset, info->y_crop_offset,
src_coef_arrays, info->drop_width, info->drop_height);
else
do_wipe(srcinfo, dstinfo, info->x_crop_offset, info->y_crop_offset,
src_coef_arrays, info->drop_width, info->drop_height);
break;
case JXFORM_DROP:
if (info->drop_width != 0 && info->drop_height != 0)
do_drop(srcinfo, dstinfo, info->x_crop_offset, info->y_crop_offset,
src_coef_arrays, info->drop_ptr, info->drop_coef_arrays,
info->drop_width, info->drop_height);
break;
}
}

34
transupp.h
View File

@@ -2,7 +2,7 @@
* transupp.h
*
* This file was part of the Independent JPEG Group's software:
* Copyright (C) 1997-2011, Thomas G. Lane, Guido Vollbeding.
* Copyright (C) 1997-2019, Thomas G. Lane, Guido Vollbeding.
* libjpeg-turbo Modifications:
* Copyright (C) 2017, D. R. Commander.
* For conditions of distribution and use, see the accompanying README.ijg
@@ -62,6 +62,17 @@
* output image covers at least the requested region, but may cover more.)
* The adjustment of the region dimensions may be optionally disabled.
*
* A complementary lossless wipe option is provided to discard (gray out) data
* inside a given image region while losslessly preserving what is outside.
* A lossless drop option is also provided, which allows another JPEG image to
* be inserted ("dropped") into the source image data at a given position,
* replacing the existing image data at that position. Both the source image
* and the drop image must have the same subsampling level. It is best if they
* also have the same quantization (quality.) Otherwise, the quantization of
* the output image will be adapted to accommodate the higher of the source
* image quality and the drop image quality. The trim option can be used with
* the drop option to requantize the drop image to match the source image.
*
* We also provide a lossless-resize option, which is kind of a lossless-crop
* operation in the DCT coefficient block domain - it discards higher-order
* coefficients and losslessly preserves lower-order coefficients of a
@@ -92,20 +103,23 @@ typedef enum {
JXFORM_TRANSVERSE, /* transpose across UR-to-LL axis */
JXFORM_ROT_90, /* 90-degree clockwise rotation */
JXFORM_ROT_180, /* 180-degree rotation */
JXFORM_ROT_270 /* 270-degree clockwise (or 90 ccw) */
JXFORM_ROT_270, /* 270-degree clockwise (or 90 ccw) */
JXFORM_WIPE, /* wipe */
JXFORM_DROP /* drop */
} JXFORM_CODE;
/*
* Codes for crop parameters, which can individually be unspecified,
* positive or negative for xoffset or yoffset,
* positive or forced for width or height.
* positive or force or reflect for width or height.
*/
typedef enum {
JCROP_UNSET,
JCROP_POS,
JCROP_NEG,
JCROP_FORCE
JCROP_FORCE,
JCROP_REFLECT
} JCROP_CODE;
/*
@@ -120,7 +134,7 @@ typedef struct {
boolean perfect; /* if TRUE, fail if partial MCUs are requested */
boolean trim; /* if TRUE, trim partial MCUs as needed */
boolean force_grayscale; /* if TRUE, convert color image to grayscale */
boolean crop; /* if TRUE, crop source image */
boolean crop; /* if TRUE, crop or wipe source image, or drop */
boolean slow_hflip; /* For best performance, the JXFORM_FLIP_H transform
normally modifies the source coefficients in place.
Setting this to TRUE will instead use a slower,
@@ -133,14 +147,18 @@ typedef struct {
* These can be filled in by jtransform_parse_crop_spec().
*/
JDIMENSION crop_width; /* Width of selected region */
JCROP_CODE crop_width_set; /* (forced disables adjustment) */
JCROP_CODE crop_width_set; /* (force-disables adjustment) */
JDIMENSION crop_height; /* Height of selected region */
JCROP_CODE crop_height_set; /* (forced disables adjustment) */
JCROP_CODE crop_height_set; /* (force-disables adjustment) */
JDIMENSION crop_xoffset; /* X offset of selected region */
JCROP_CODE crop_xoffset_set; /* (negative measures from right edge) */
JDIMENSION crop_yoffset; /* Y offset of selected region */
JCROP_CODE crop_yoffset_set; /* (negative measures from bottom edge) */
/* Drop parameters: set by caller for drop request */
j_decompress_ptr drop_ptr;
jvirt_barray_ptr *drop_coef_arrays;
/* Internal workspace: caller should not touch these */
int num_components; /* # of components in workspace */
jvirt_barray_ptr *workspace_coef_arrays; /* workspace for transformations */
@@ -148,6 +166,8 @@ typedef struct {
JDIMENSION output_height;
JDIMENSION x_crop_offset; /* destination crop offsets measured in iMCUs */
JDIMENSION y_crop_offset;
JDIMENSION drop_width; /* drop/wipe dimensions measured in iMCUs */
JDIMENSION drop_height;
int iMCU_sample_width; /* destination iMCU size */
int iMCU_sample_height;
} jpeg_transform_info;

75
usage.txt
View File

@@ -50,9 +50,9 @@ or
This syntax works on all systems, so it is useful for scripts.
The currently supported image file formats are: PPM (PBMPLUS color format),
PGM (PBMPLUS grayscale format), BMP, and Targa. cjpeg recognizes the input
image format automatically, with the exception of some Targa files. You have
to tell djpeg which format to generate.
PGM (PBMPLUS grayscale format), BMP, GIF, and Targa. cjpeg recognizes the
input image format automatically, with the exception of some Targa files. You
have to tell djpeg which format to generate.
JPEG files are in the defacto standard JFIF file format. There are other,
less widely used JPEG-based file formats, but we don't support them.
@@ -74,10 +74,10 @@ The basic command line switches for cjpeg are:
-grayscale Create monochrome JPEG file from color input.
Be sure to use this switch when compressing a grayscale
BMP file, because cjpeg isn't bright enough to notice
whether a BMP file uses only shades of gray. By
saying -grayscale, you'll get a smaller JPEG file that
takes less time to process.
BMP or GIF file, because cjpeg isn't bright enough to
notice whether a BMP or GIF file uses only shades of
gray. By saying -grayscale, you'll get a smaller JPEG
file that takes less time to process.
-rgb Create RGB JPEG file.
Using this switch suppresses the conversion from RGB
@@ -288,10 +288,17 @@ The basic command line switches for djpeg are:
is specified, or if the JPEG file is grayscale;
otherwise, 24-bit full-color format is emitted.
-gif Select GIF output format. Since GIF does not support
more than 256 colors, -colors 256 is assumed (unless
you specify a smaller number of colors). If you
specify -fast, the default number of colors is 216.
-gif Select GIF output format (LZW-compressed). Since GIF
does not support more than 256 colors, -colors 256 is
assumed (unless you specify a smaller number of
colors). If you specify -fast, the default number of
colors is 216.
-gif0 Select GIF output format (uncompressed). Since GIF
does not support more than 256 colors, -colors 256 is
assumed (unless you specify a smaller number of
colors). If you specify -fast, the default number of
colors is 216.
-os2 Select BMP output format (OS/2 1.x flavor). 8-bit
colormapped format is emitted if -colors or -grayscale
@@ -400,11 +407,6 @@ quality settings to make very small JPEG files; the percentage improvement
is often a lot more than it is on larger files. (At present, -optimize
mode is always selected when generating progressive JPEG files.)
Support for GIF input files was removed in cjpeg v6b due to concerns over
the Unisys LZW patent. Although this patent expired in 2006, cjpeg still
lacks GIF support, for these historical reasons. (Conversion of GIF files to
JPEG is usually a bad idea anyway.)
HINTS FOR DJPEG
@@ -419,10 +421,6 @@ When producing a color-quantized image, "-onepass -dither ordered" is fast but
much lower quality than the default behavior. "-dither none" may give
acceptable results in two-pass mode, but is seldom tolerable in one-pass mode.
To avoid the Unisys LZW patent (now expired), djpeg produces uncompressed GIF
files. These are larger than they should be, but are readable by standard GIF
decoders.
HINTS FOR BOTH PROGRAMS
@@ -529,6 +527,43 @@ The image can be losslessly cropped by giving the switch:
-crop WxH+X+Y Crop to a rectangular region of width W and height H,
starting at point X,Y.
If W or H is larger than the width/height of the input image, then the output
image is expanded in size, and the expanded region is filled in with zeros
(neutral gray). Attaching an 'f' character ("flatten") to the width number
will cause each block in the expanded region to be filled in with the DC
coefficient of the nearest block in the input image rather than grayed out.
Attaching an 'r' character ("reflect") to the width number will cause the
expanded region to be filled in with repeated reflections of the input image
rather than grayed out.
A complementary lossless wipe option is provided to discard (gray out) data
inside a given image region while losslessly preserving what is outside:
-wipe WxH+X+Y Wipe (gray out) a rectangular region of width W and
height H from the input image, starting at point X,Y.
Attaching an 'f' character ("flatten") to the width number will cause the
region to be filled with the average of adjacent blocks rather than grayed out.
If the wipe region and the region outside the wipe region, when adjusted to the
nearest iMCU boundary, form two horizontally adjacent rectangles, then
attaching an 'r' character ("reflect") to the width number will cause the wipe
region to be filled with repeated reflections of the outside region rather than
grayed out.
A lossless drop option is also provided, which allows another JPEG image to be
inserted ("dropped") into the input image data at a given position, replacing
the existing image data at that position:
-drop +X+Y filename Drop (insert) another image at point X,Y
Both the input image and the drop image must have the same subsampling level.
It is best if they also have the same quantization (quality.) Otherwise, the
quantization of the output image will be adapted to accommodate the higher of
the input image quality and the drop image quality. The trim option can be
used with the drop option to requantize the drop image to match the input
image. Note that a grayscale image can be dropped into a full-color image or
vice versa, as long as the full-color image has no vertical subsampling. If
the input image is grayscale and the drop image is full-color, then the
chrominance channels from the drop image will be discarded.
Other not-strictly-lossless transformation switches are:
-grayscale Force grayscale output.

315
wrgif.c
View File

@@ -3,6 +3,7 @@
*
* This file was part of the Independent JPEG Group's software:
* Copyright (C) 1991-1997, Thomas G. Lane.
* Modified 2015-2019 by Guido Vollbeding.
* libjpeg-turbo Modifications:
* Copyright (C) 2015, 2017, D. R. Commander.
* For conditions of distribution and use, see the accompanying README.ijg
@@ -10,12 +11,6 @@
*
* This file contains routines to write output images in GIF format.
*
**************************************************************************
* NOTE: to avoid entanglements with Unisys' patent on LZW compression, *
* this code has been modified to output "uncompressed GIF" files. *
* There is no trace of the LZW algorithm in this file. *
**************************************************************************
*
* These routines may need modification for non-Unix environments or
* specialized applications. As they stand, they assume output to
* an ordinary stdio stream.
@@ -33,11 +28,6 @@
* copyright notice and this permission notice appear in supporting
* documentation. This software is provided "as is" without express or
* implied warranty.
*
* We are also required to state that
* "The Graphics Interchange Format(c) is the Copyright property of
* CompuServe Incorporated. GIF(sm) is a Service Mark property of
* CompuServe Incorporated."
*/
#include "cdjpeg.h" /* Common decls for cjpeg/djpeg applications */
@@ -45,6 +35,37 @@
#ifdef GIF_SUPPORTED
#define MAX_LZW_BITS 12 /* maximum LZW code size (4096 symbols) */
typedef INT16 code_int; /* must hold -1 .. 2**MAX_LZW_BITS */
#define LZW_TABLE_SIZE ((code_int)1 << MAX_LZW_BITS)
#define HSIZE 5003 /* hash table size for 80% occupancy */
typedef int hash_int; /* must hold -2*HSIZE..2*HSIZE */
#define MAXCODE(n_bits) (((code_int)1 << (n_bits)) - 1)
/*
* The LZW hash table consists of two parallel arrays:
* hash_code[i] code of symbol in slot i, or 0 if empty slot
* hash_value[i] symbol's value; undefined if empty slot
* where slot values (i) range from 0 to HSIZE-1. The symbol value is
* its prefix symbol's code concatenated with its suffix character.
*
* Algorithm: use open addressing double hashing (no chaining) on the
* prefix code / suffix character combination. We do a variant of Knuth's
* algorithm D (vol. 3, sec. 6.4) along with G. Knott's relatively-prime
* secondary probe.
*/
typedef int hash_entry; /* must hold (code_int << 8) | byte */
#define HASH_ENTRY(prefix, suffix) ((((hash_entry)(prefix)) << 8) | (suffix))
/* Private version of data destination object */
typedef struct {
@@ -54,14 +75,24 @@ typedef struct {
/* State for packing variable-width codes into a bitstream */
int n_bits; /* current number of bits/code */
int maxcode; /* maximum code, given n_bits */
long cur_accum; /* holds bits not yet output */
code_int maxcode; /* maximum code, given n_bits */
int init_bits; /* initial n_bits ... restored after clear */
int cur_accum; /* holds bits not yet output */
int cur_bits; /* # of bits in cur_accum */
/* LZW string construction */
code_int waiting_code; /* symbol not yet output; may be extendable */
boolean first_byte; /* if TRUE, waiting_code is not valid */
/* State for GIF code assignment */
int ClearCode; /* clear code (doesn't change) */
int EOFCode; /* EOF code (ditto) */
int code_counter; /* counts output symbols */
code_int ClearCode; /* clear code (doesn't change) */
code_int EOFCode; /* EOF code (ditto) */
code_int free_code; /* LZW: first not-yet-used symbol code */
code_int code_counter; /* not LZW: counts output symbols */
/* LZW hash table */
code_int *hash_code; /* => hash table of symbol codes */
hash_entry *hash_value; /* => hash table of symbol values */
/* GIF data packet construction buffer */
int bytesinpkt; /* # of bytes in current packet */
@@ -71,9 +102,6 @@ typedef struct {
typedef gif_dest_struct *gif_dest_ptr;
/* Largest value that will fit in N bits */
#define MAXCODE(n_bits) ((1 << (n_bits)) - 1)
/*
* Routines to package finished data bytes into GIF data blocks.
@@ -105,7 +133,7 @@ flush_packet(gif_dest_ptr dinfo)
/* Routine to convert variable-width codes into a byte stream */
LOCAL(void)
output(gif_dest_ptr dinfo, int code)
output(gif_dest_ptr dinfo, code_int code)
/* Emit a code of n_bits bits */
/* Uses cur_accum and cur_bits to reblock into 8-bit bytes */
{
@@ -117,74 +145,76 @@ output(gif_dest_ptr dinfo, int code)
dinfo->cur_accum >>= 8;
dinfo->cur_bits -= 8;
}
/*
* If the next entry is going to be too big for the code size,
* then increase it, if possible. We do this here to ensure
* that it's done in sync with the decoder's codesize increases.
*/
if (dinfo->free_code > dinfo->maxcode) {
dinfo->n_bits++;
if (dinfo->n_bits == MAX_LZW_BITS)
dinfo->maxcode = LZW_TABLE_SIZE; /* free_code will never exceed this */
else
dinfo->maxcode = MAXCODE(dinfo->n_bits);
}
}
/* The pseudo-compression algorithm.
*
* In this module we simply output each pixel value as a separate symbol;
* thus, no compression occurs. In fact, there is expansion of one bit per
* pixel, because we use a symbol width one bit wider than the pixel width.
*
* GIF ordinarily uses variable-width symbols, and the decoder will expect
* to ratchet up the symbol width after a fixed number of symbols.
* To simplify the logic and keep the expansion penalty down, we emit a
* GIF Clear code to reset the decoder just before the width would ratchet up.
* Thus, all the symbols in the output file will have the same bit width.
* Note that emitting the Clear codes at the right times is a mere matter of
* counting output symbols and is in no way dependent on the LZW patent.
*
* With a small basic pixel width (low color count), Clear codes will be
* needed very frequently, causing the file to expand even more. So this
* simplistic approach wouldn't work too well on bilevel images, for example.
* But for output of JPEG conversions the pixel width will usually be 8 bits
* (129 to 256 colors), so the overhead added by Clear symbols is only about
* one symbol in every 256.
*/
/* Compression initialization & termination */
LOCAL(void)
clear_hash(gif_dest_ptr dinfo)
/* Fill the hash table with empty entries */
{
/* It's sufficient to zero hash_code[] */
MEMZERO(dinfo->hash_code, HSIZE * sizeof(code_int));
}
LOCAL(void)
clear_block(gif_dest_ptr dinfo)
/* Reset compressor and issue a Clear code */
{
clear_hash(dinfo); /* delete all the symbols */
dinfo->free_code = dinfo->ClearCode + 2;
output(dinfo, dinfo->ClearCode); /* inform decoder */
dinfo->n_bits = dinfo->init_bits; /* reset code size */
dinfo->maxcode = MAXCODE(dinfo->n_bits);
}
LOCAL(void)
compress_init(gif_dest_ptr dinfo, int i_bits)
/* Initialize pseudo-compressor */
/* Initialize compressor */
{
/* init all the state variables */
dinfo->n_bits = i_bits;
dinfo->n_bits = dinfo->init_bits = i_bits;
dinfo->maxcode = MAXCODE(dinfo->n_bits);
dinfo->ClearCode = (1 << (i_bits - 1));
dinfo->ClearCode = ((code_int) 1 << (i_bits - 1));
dinfo->EOFCode = dinfo->ClearCode + 1;
dinfo->code_counter = dinfo->ClearCode + 2;
dinfo->code_counter = dinfo->free_code = dinfo->ClearCode + 2;
dinfo->first_byte = TRUE; /* no waiting symbol yet */
/* init output buffering vars */
dinfo->bytesinpkt = 0;
dinfo->cur_accum = 0;
dinfo->cur_bits = 0;
/* clear hash table */
if (dinfo->hash_code != NULL)
clear_hash(dinfo);
/* GIF specifies an initial Clear code */
output(dinfo, dinfo->ClearCode);
}
LOCAL(void)
compress_pixel(gif_dest_ptr dinfo, int c)
/* Accept and "compress" one pixel value.
* The given value must be less than n_bits wide.
*/
{
/* Output the given pixel value as a symbol. */
output(dinfo, c);
/* Issue Clear codes often enough to keep the reader from ratcheting up
* its symbol size.
*/
if (dinfo->code_counter < dinfo->maxcode) {
dinfo->code_counter++;
} else {
output(dinfo, dinfo->ClearCode);
dinfo->code_counter = dinfo->ClearCode + 2; /* reset the counter */
}
}
LOCAL(void)
compress_term(gif_dest_ptr dinfo)
/* Clean up at end */
{
/* Flush out the buffered LZW code */
if (!dinfo->first_byte)
output(dinfo, dinfo->waiting_code);
/* Send an EOF code */
output(dinfo, dinfo->EOFCode);
/* Flush the bit-packing buffer */
@@ -221,7 +251,7 @@ put_3bytes(gif_dest_ptr dinfo, int val)
LOCAL(void)
emit_header(gif_dest_ptr dinfo, int num_colors, JSAMPARRAY colormap)
/* Output the GIF file header, including color map */
/* If colormap==NULL, synthesize a grayscale colormap */
/* If colormap == NULL, synthesize a grayscale colormap */
{
int BitsPerPixel, ColorMapSize, InitCodeSize, FlagByte;
int cshift = dinfo->cinfo->data_precision - 8;
@@ -278,7 +308,7 @@ emit_header(gif_dest_ptr dinfo, int num_colors, JSAMPARRAY colormap)
}
} else {
/* fill out the map to a power of 2 */
put_3bytes(dinfo, 0);
put_3bytes(dinfo, CENTERJSAMPLE >> cshift);
}
}
/* Write image separator and Image Descriptor */
@@ -292,7 +322,7 @@ emit_header(gif_dest_ptr dinfo, int num_colors, JSAMPARRAY colormap)
/* Write Initial Code Size byte */
putc(InitCodeSize, dinfo->pub.output_file);
/* Initialize for "compression" of image data */
/* Initialize for compression of image data */
compress_init(dinfo, InitCodeSize + 1);
}
@@ -318,17 +348,139 @@ start_output_gif(j_decompress_ptr cinfo, djpeg_dest_ptr dinfo)
* In this module rows_supplied will always be 1.
*/
/*
* The LZW algorithm proper
*/
METHODDEF(void)
put_pixel_rows(j_decompress_ptr cinfo, djpeg_dest_ptr dinfo,
JDIMENSION rows_supplied)
put_LZW_pixel_rows(j_decompress_ptr cinfo, djpeg_dest_ptr dinfo,
JDIMENSION rows_supplied)
{
gif_dest_ptr dest = (gif_dest_ptr)dinfo;
register JSAMPROW ptr;
register JDIMENSION col;
code_int c;
register hash_int i;
register hash_int disp;
register hash_entry probe_value;
ptr = dest->pub.buffer[0];
for (col = cinfo->output_width; col > 0; col--) {
compress_pixel(dest, *ptr++);
/* Accept and compress one 8-bit byte */
c = (code_int)(*ptr++);
if (dest->first_byte) { /* need to initialize waiting_code */
dest->waiting_code = c;
dest->first_byte = FALSE;
continue;
}
/* Probe hash table to see if a symbol exists for
* waiting_code followed by c.
* If so, replace waiting_code by that symbol and continue.
*/
i = ((hash_int)c << (MAX_LZW_BITS - 8)) + dest->waiting_code;
/* i is less than twice 2**MAX_LZW_BITS, therefore less than twice HSIZE */
if (i >= HSIZE)
i -= HSIZE;
probe_value = HASH_ENTRY(dest->waiting_code, c);
if (dest->hash_code[i] == 0) {
/* hit empty slot; desired symbol not in table */
output(dest, dest->waiting_code);
if (dest->free_code < LZW_TABLE_SIZE) {
dest->hash_code[i] = dest->free_code++; /* add symbol to hashtable */
dest->hash_value[i] = probe_value;
} else
clear_block(dest);
dest->waiting_code = c;
continue;
}
if (dest->hash_value[i] == probe_value) {
dest->waiting_code = dest->hash_code[i];
continue;
}
if (i == 0) /* secondary hash (after G. Knott) */
disp = 1;
else
disp = HSIZE - i;
for (;;) {
i -= disp;
if (i < 0)
i += HSIZE;
if (dest->hash_code[i] == 0) {
/* hit empty slot; desired symbol not in table */
output(dest, dest->waiting_code);
if (dest->free_code < LZW_TABLE_SIZE) {
dest->hash_code[i] = dest->free_code++; /* add symbol to hashtable */
dest->hash_value[i] = probe_value;
} else
clear_block(dest);
dest->waiting_code = c;
break;
}
if (dest->hash_value[i] == probe_value) {
dest->waiting_code = dest->hash_code[i];
break;
}
}
}
}
/*
* The pseudo-compression algorithm.
*
* In this version we simply output each pixel value as a separate symbol;
* thus, no compression occurs. In fact, there is expansion of one bit per
* pixel, because we use a symbol width one bit wider than the pixel width.
*
* GIF ordinarily uses variable-width symbols, and the decoder will expect
* to ratchet up the symbol width after a fixed number of symbols.
* To simplify the logic and keep the expansion penalty down, we emit a
* GIF Clear code to reset the decoder just before the width would ratchet up.
* Thus, all the symbols in the output file will have the same bit width.
* Note that emitting the Clear codes at the right times is a mere matter of
* counting output symbols and is in no way dependent on the LZW algorithm.
*
* With a small basic pixel width (low color count), Clear codes will be
* needed very frequently, causing the file to expand even more. So this
* simplistic approach wouldn't work too well on bilevel images, for example.
* But for output of JPEG conversions the pixel width will usually be 8 bits
* (129 to 256 colors), so the overhead added by Clear symbols is only about
* one symbol in every 256.
*/
METHODDEF(void)
put_raw_pixel_rows(j_decompress_ptr cinfo, djpeg_dest_ptr dinfo,
JDIMENSION rows_supplied)
{
gif_dest_ptr dest = (gif_dest_ptr)dinfo;
register JSAMPROW ptr;
register JDIMENSION col;
code_int c;
ptr = dest->pub.buffer[0];
for (col = cinfo->output_width; col > 0; col--) {
c = (code_int)(*ptr++);
/* Accept and output one pixel value.
* The given value must be less than n_bits wide.
*/
/* Output the given pixel value as a symbol. */
output(dest, c);
/* Issue Clear codes often enough to keep the reader from ratcheting up
* its symbol size.
*/
if (dest->code_counter < dest->maxcode) {
dest->code_counter++;
} else {
output(dest, dest->ClearCode);
dest->code_counter = dest->ClearCode + 2; /* reset the counter */
}
}
}
@@ -342,7 +494,7 @@ finish_output_gif(j_decompress_ptr cinfo, djpeg_dest_ptr dinfo)
{
gif_dest_ptr dest = (gif_dest_ptr)dinfo;
/* Flush "compression" mechanism */
/* Flush compression mechanism */
compress_term(dest);
/* Write a zero-length data block to end the series */
putc(0, dest->pub.output_file);
@@ -370,7 +522,7 @@ calc_buffer_dimensions_gif(j_decompress_ptr cinfo, djpeg_dest_ptr dinfo)
*/
GLOBAL(djpeg_dest_ptr)
jinit_write_gif(j_decompress_ptr cinfo)
jinit_write_gif(j_decompress_ptr cinfo, boolean is_lzw)
{
gif_dest_ptr dest;
@@ -380,7 +532,6 @@ jinit_write_gif(j_decompress_ptr cinfo)
sizeof(gif_dest_struct));
dest->cinfo = cinfo; /* make back link for subroutines */
dest->pub.start_output = start_output_gif;
dest->pub.put_pixel_rows = put_pixel_rows;
dest->pub.finish_output = finish_output_gif;
dest->pub.calc_buffer_dimensions = calc_buffer_dimensions_gif;
@@ -407,6 +558,22 @@ jinit_write_gif(j_decompress_ptr cinfo)
((j_common_ptr)cinfo, JPOOL_IMAGE, cinfo->output_width, (JDIMENSION)1);
dest->pub.buffer_height = 1;
if (is_lzw) {
dest->pub.put_pixel_rows = put_LZW_pixel_rows;
/* Allocate space for hash table */
dest->hash_code = (code_int *)
(*cinfo->mem->alloc_small) ((j_common_ptr)cinfo, JPOOL_IMAGE,
HSIZE * sizeof(code_int));
dest->hash_value = (hash_entry *)
(*cinfo->mem->alloc_large) ((j_common_ptr)cinfo, JPOOL_IMAGE,
HSIZE * sizeof(hash_entry));
} else {
dest->pub.put_pixel_rows = put_raw_pixel_rows;
/* Mark tables unused */
dest->hash_code = NULL;
dest->hash_value = NULL;
}
return (djpeg_dest_ptr)dest;
}