19c791cdac
With rare exceptions ...
- Always separate line continuation characters by one space from
preceding code.
- Always use two-space indentation. Never use tabs.
- Always use K&R-style conditional blocks.
- Always surround operators with spaces, except in raw assembly code.
- Always put a space after, but not before, a comma.
- Never put a space between type casts and variables/function calls.
- Never put a space between the function name and the argument list in
function declarations and prototypes.
- Always surround braces ('{' and '}') with spaces.
- Always surround statements (if, for, else, catch, while, do, switch)
with spaces.
- Always attach pointer symbols ('*' and '**') to the variable or
function name.
- Always precede pointer symbols ('*' and '**') by a space in type
casts.
- Use the MIN() macro from jpegint.h within the libjpeg and TurboJPEG
API libraries (using min() from tjutil.h is still necessary for
TJBench.)
- Where it makes sense (particularly in the TurboJPEG code), put a blank
line after variable declaration blocks.
- Always separate statements in one-liners by two spaces.
The purpose of this was to ease maintenance on my part and also to make
it easier for contributors to figure out how to format patch
submissions. This was admittedly confusing (even to me sometimes) when
we had 3 or 4 different style conventions in the same source tree. The
new convention is more consistent with the formatting of other OSS code
bases.
This commit corrects deviations from the chosen formatting style in the
libjpeg API code and reformats the TurboJPEG API code such that it
conforms to the same standard.
NOTES:
- Although it is no longer necessary for the function name in function
declarations to begin in Column 1 (this was historically necessary
because of the ansi2knr utility, which allowed libjpeg to be built
with non-ANSI compilers), we retain that formatting for the libjpeg
code because it improves readability when using libjpeg's function
attribute macros (GLOBAL(), etc.)
- This reformatting project was accomplished with the help of AStyle and
Uncrustify, although neither was completely up to the task, and thus
a great deal of manual tweaking was required. Note to developers of
code formatting utilities: the libjpeg-turbo code base is an
excellent test bed, because AFAICT, it breaks every single one of the
utilities that are currently available.
- The legacy (MMX, SSE, 3DNow!) assembly code for i386 has been
formatted to match the SSE2 code (refer to
ff5685d5344273df321eb63a005eaae19d2496e3.) I hadn't intended to
bother with this, but the Loongson MMI implementation demonstrated
that there is still academic value to the MMX implementation, as an
algorithmic model for other 64-bit vector implementations. Thus, it
is desirable to improve its readability in the same manner as that of
the SSE2 implementation.
145 lines
4.5 KiB
C
145 lines
4.5 KiB
C
/*
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* jccolext.c
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*
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* This file was part of the Independent JPEG Group's software:
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* Copyright (C) 1991-1996, Thomas G. Lane.
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* libjpeg-turbo Modifications:
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* Copyright (C) 2009-2012, 2015, D. R. Commander.
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* For conditions of distribution and use, see the accompanying README.ijg
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* file.
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*
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* This file contains input colorspace conversion routines.
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*/
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/* This file is included by jccolor.c */
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/*
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* Convert some rows of samples to the JPEG colorspace.
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*
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* Note that we change from the application's interleaved-pixel format
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* to our internal noninterleaved, one-plane-per-component format.
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* The input buffer is therefore three times as wide as the output buffer.
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*
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* A starting row offset is provided only for the output buffer. The caller
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* can easily adjust the passed input_buf value to accommodate any row
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* offset required on that side.
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*/
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INLINE
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LOCAL(void)
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rgb_ycc_convert_internal(j_compress_ptr cinfo, JSAMPARRAY input_buf,
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JSAMPIMAGE output_buf, JDIMENSION output_row,
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int num_rows)
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{
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my_cconvert_ptr cconvert = (my_cconvert_ptr)cinfo->cconvert;
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register int r, g, b;
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register JLONG *ctab = cconvert->rgb_ycc_tab;
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register JSAMPROW inptr;
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register JSAMPROW outptr0, outptr1, outptr2;
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register JDIMENSION col;
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JDIMENSION num_cols = cinfo->image_width;
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while (--num_rows >= 0) {
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inptr = *input_buf++;
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outptr0 = output_buf[0][output_row];
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outptr1 = output_buf[1][output_row];
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outptr2 = output_buf[2][output_row];
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output_row++;
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for (col = 0; col < num_cols; col++) {
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r = GETJSAMPLE(inptr[RGB_RED]);
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g = GETJSAMPLE(inptr[RGB_GREEN]);
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b = GETJSAMPLE(inptr[RGB_BLUE]);
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inptr += RGB_PIXELSIZE;
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/* If the inputs are 0..MAXJSAMPLE, the outputs of these equations
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* must be too; we do not need an explicit range-limiting operation.
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* Hence the value being shifted is never negative, and we don't
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* need the general RIGHT_SHIFT macro.
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*/
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/* Y */
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outptr0[col] = (JSAMPLE)((ctab[r + R_Y_OFF] + ctab[g + G_Y_OFF] +
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ctab[b + B_Y_OFF]) >> SCALEBITS);
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/* Cb */
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outptr1[col] = (JSAMPLE)((ctab[r + R_CB_OFF] + ctab[g + G_CB_OFF] +
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ctab[b + B_CB_OFF]) >> SCALEBITS);
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/* Cr */
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outptr2[col] = (JSAMPLE)((ctab[r + R_CR_OFF] + ctab[g + G_CR_OFF] +
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ctab[b + B_CR_OFF]) >> SCALEBITS);
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}
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}
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}
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/**************** Cases other than RGB -> YCbCr **************/
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/*
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* Convert some rows of samples to the JPEG colorspace.
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* This version handles RGB->grayscale conversion, which is the same
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* as the RGB->Y portion of RGB->YCbCr.
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* We assume rgb_ycc_start has been called (we only use the Y tables).
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*/
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INLINE
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LOCAL(void)
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rgb_gray_convert_internal(j_compress_ptr cinfo, JSAMPARRAY input_buf,
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JSAMPIMAGE output_buf, JDIMENSION output_row,
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int num_rows)
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{
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my_cconvert_ptr cconvert = (my_cconvert_ptr)cinfo->cconvert;
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register int r, g, b;
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register JLONG *ctab = cconvert->rgb_ycc_tab;
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register JSAMPROW inptr;
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register JSAMPROW outptr;
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register JDIMENSION col;
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JDIMENSION num_cols = cinfo->image_width;
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while (--num_rows >= 0) {
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inptr = *input_buf++;
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outptr = output_buf[0][output_row];
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output_row++;
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for (col = 0; col < num_cols; col++) {
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r = GETJSAMPLE(inptr[RGB_RED]);
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g = GETJSAMPLE(inptr[RGB_GREEN]);
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b = GETJSAMPLE(inptr[RGB_BLUE]);
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inptr += RGB_PIXELSIZE;
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/* Y */
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outptr[col] = (JSAMPLE)((ctab[r + R_Y_OFF] + ctab[g + G_Y_OFF] +
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ctab[b + B_Y_OFF]) >> SCALEBITS);
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}
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}
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}
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/*
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* Convert some rows of samples to the JPEG colorspace.
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* This version handles extended RGB->plain RGB conversion
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*/
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INLINE
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LOCAL(void)
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rgb_rgb_convert_internal(j_compress_ptr cinfo, JSAMPARRAY input_buf,
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JSAMPIMAGE output_buf, JDIMENSION output_row,
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int num_rows)
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{
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register JSAMPROW inptr;
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register JSAMPROW outptr0, outptr1, outptr2;
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register JDIMENSION col;
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JDIMENSION num_cols = cinfo->image_width;
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while (--num_rows >= 0) {
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inptr = *input_buf++;
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outptr0 = output_buf[0][output_row];
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outptr1 = output_buf[1][output_row];
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outptr2 = output_buf[2][output_row];
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output_row++;
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for (col = 0; col < num_cols; col++) {
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outptr0[col] = GETJSAMPLE(inptr[RGB_RED]);
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outptr1[col] = GETJSAMPLE(inptr[RGB_GREEN]);
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outptr2[col] = GETJSAMPLE(inptr[RGB_BLUE]);
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inptr += RGB_PIXELSIZE;
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}
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}
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}
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