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Merge branch 'master' into dev

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This commit is contained in:
DRC
2017-06-26 21:58:32 -05:00
parent 44b2399a94 6a2b067428
commit 2ac4e9d914
16 changed files with 204 additions and 93 deletions
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3
.travis.yml
View File

@@ -49,7 +49,8 @@ matrix:
before_install:
- if [ "$TRAVIS_OS_NAME" = "osx" ]; then
brew install nasm homebrew/versions/gcc5 md5sha1sum Caskroom/versions/java6 gpg &&
brew install nasm homebrew/versions/gcc5 md5sha1sum Caskroom/versions/java6 &&
ln -fs /usr/local/bin/gpg1 /usr/local/bin/gpg &&
git clone --depth=1 https://github.com/libjpeg-turbo/gas-preprocessor.git ~/src/gas-preprocessor &&
ln -fs /Applications/Xcode.app /Applications/Xcode72.app;
fi

75
BUILDING.md
View File

@@ -539,7 +539,7 @@ needs.
export LDFLAGS=-pie
TOOLCHAIN=${NDK_PATH}/toolchains/${HOST}-${TOOLCHAIN_VERSION}/prebuilt/${BUILD_PLATFORM}
cat <<EOF >android.cmake
cat <<EOF >toolchain.cmake
set(CMAKE_SYSTEM_NAME Linux)
set(CMAKE_SYSTEM_PROCESSOR arm)
set(CMAKE_C_COMPILER ${TOOLCHAIN}/bin/${HOST}-gcc)
@@ -570,7 +570,7 @@ needs.
# It should not be necessary to modify the rest
HOST=aarch64-linux-android
SYSROOT=${NDK_PATH}/platforms/android-${ANDROID_VERSION}/arch-arm64
export CFLAGS="--sysroot ${SYSROOT}"
export CFLAGS="--sysroot=${SYSROOT}"
export LDFLAGS=-pie
TOOLCHAIN=${NDK_PATH}/toolchains/${HOST}-${TOOLCHAIN_VERSION}/prebuilt/${BUILD_PLATFORM}
@@ -587,6 +587,77 @@ needs.
[additional CMake flags] {source_directory}
make
### x86 (32-bit)
The following is a general recipe script that can be modified for your specific
needs.
# Set these variables to suit your needs
NDK_PATH={full path to the "ndk" directory-- for example, /opt/android/sdk/ndk-bundle}
BUILD_PLATFORM={the platform name for the NDK package you installed--
for example, "windows-x86" or "linux-x86_64" or "darwin-x86_64"}
TOOLCHAIN_VERSION={"4.8", "4.9", "clang3.5", etc. This corresponds to a
toolchain directory under ${NDK_PATH}/toolchains/.}
ANDROID_VERSION={The minimum version of Android to support-- for example,
"16", "19", etc.}
# It should not be necessary to modify the rest
HOST=i686-linux-android
SYSROOT=${NDK_PATH}/platforms/android-${ANDROID_VERSION}/arch-x86
export CFLAGS="--sysroot=${SYSROOT}"
export LDFLAGS=-pie
TOOLCHAIN=${NDK_PATH}/toolchains/x86-${TOOLCHAIN_VERSION}/prebuilt/${BUILD_PLATFORM}
cat <<EOF >toolchain.cmake
set(CMAKE_SYSTEM_NAME Linux)
set(CMAKE_SYSTEM_PROCESSOR i386)
set(CMAKE_C_COMPILER ${TOOLCHAIN}/bin/${HOST}-gcc)
set(CMAKE_FIND_ROOT_PATH ${TOOLCHAIN}/${HOST})
EOF
cd {build_directory}
cmake -G"Unix Makefiles" -DCMAKE_TOOLCHAIN_FILE=toolchain.cmake \
-DCMAKE_POSITION_INDEPENDENT_CODE=1 \
[additional CMake flags] {source_directory}
make
### x86-64 (64-bit)
The following is a general recipe script that can be modified for your specific
needs.
# Set these variables to suit your needs
NDK_PATH={full path to the "ndk" directory-- for example, /opt/android/sdk/ndk-bundle}
BUILD_PLATFORM={the platform name for the NDK package you installed--
for example, "windows-x86" or "linux-x86_64" or "darwin-x86_64"}
TOOLCHAIN_VERSION={"4.8", "4.9", "clang3.5", etc. This corresponds to a
toolchain directory under ${NDK_PATH}/toolchains/.}
ANDROID_VERSION={The minimum version of Android to support. "21" or later
is required for a 64-bit build.}
# It should not be necessary to modify the rest
HOST=x86_64-linux-android
SYSROOT=${NDK_PATH}/platforms/android-${ANDROID_VERSION}/arch-x86_64
export CFLAGS="--sysroot=${SYSROOT}"
export LDFLAGS=-pie
TOOLCHAIN=${NDK_PATH}/toolchains/x86_64-${TOOLCHAIN_VERSION}/prebuilt/${BUILD_PLATFORM}
cat <<EOF >toolchain.cmake
set(CMAKE_SYSTEM_NAME Linux)
set(CMAKE_SYSTEM_PROCESSOR x86_64)
set(CMAKE_C_COMPILER ${TOOLCHAIN}/bin/${HOST}-gcc)
set(CMAKE_FIND_ROOT_PATH ${TOOLCHAIN}/${HOST})
EOF
cd {build_directory}
cmake -G"Unix Makefiles" -DCMAKE_TOOLCHAIN_FILE=toolchain.cmake \
-DCMAKE_POSITION_INDEPENDENT_CODE=1 \
[additional CMake flags] {source_directory}
make
If building for Android 4.0.x (API level < 16) or earlier, remove
`-DCMAKE_POSITION_INDEPENDENT_CODE=1` from the CMake arguments and `-pie` from
`LDFLAGS`.

21
ChangeLog.md
View File

@@ -81,6 +81,27 @@ API/ABI emulation, since the behavior is entirely internal. Note that
`-copy all` must be passed to jpegtran in order to transfer the EXIF tags from
the source image to the destination image.
8. Fixed several memory leaks in the TurboJPEG API library that could occur
if the library was built with certain compilers and optimization levels
(known to occur with GCC 4.x and clang with `-O1` and higher but not with
GCC 5.x or 6.x) and one of the underlying libjpeg API functions threw an error
after a TurboJPEG API function allocated a local buffer.
9. The libjpeg-turbo memory manager will now honor the `max_memory_to_use`
structure member in jpeg\_memory\_mgr, which can be set to the maximum amount
of memory (in bytes) that libjpeg-turbo should use during decompression or
multi-pass (including progressive) compression. This limit can also be set
using the `JPEGMEM` environment variable or using the `-maxmemory` switch in
cjpeg/djpeg/jpegtran (refer to the respective man pages for more details.)
This has been a documented feature of libjpeg since v5, but the
`malloc()`/`free()` implementation of the memory manager (jmemnobs.c) never
implemented the feature. Restricting libjpeg-turbo's memory usage is useful
for two reasons: it allows testers to more easily work around the 2 GB limit
in libFuzzer, and it allows developers of security-sensitive applications to
more easily defend against one of the progressive JPEG exploits (LJT-01-004)
identified in
[this report](http://www.libjpeg-turbo.org/pmwiki/uploads/About/TwoIssueswiththeJPEGStandard.pdf).
1.5.1
=====

4
appveyor.yml
View File

@@ -24,7 +24,9 @@ install:
build_script:
- cmd: >-
bash c:/buildscripts/buildljt -r file://%CD:\=/% -b /c/ljt.nightly %APPVEYOR_REPO_BRANCH% -v
for /f %%i in ('"cygpath %CD%"') do set MINGWPATH=%%i
bash c:/buildscripts/buildljt -r file://%MINGWPATH% -b /c/ljt.nightly %APPVEYOR_REPO_BRANCH% -v
move c:\ljt.nightly\files\*.tar.gz .

4
cjpeg.1
View File

@@ -1,4 +1,4 @@
.TH CJPEG 1 "19 January 2017"
.TH CJPEG 1 "18 March 2017"
.SH NAME
cjpeg \- compress an image file to a JPEG file
.SH SYNOPSIS
@@ -205,7 +205,7 @@ Set limit for amount of memory to use in processing large images. Value is
in thousands of bytes, or millions of bytes if "M" is attached to the
number. For example,
.B \-max 4m
selects 4000000 bytes. If more space is needed, temporary files will be used.
selects 4000000 bytes. If more space is needed, an error will occur.
.TP
.BI \-outfile " name"
Send output image to the named file, not to standard output.

4
djpeg.1
View File

@@ -1,4 +1,4 @@
.TH DJPEG 1 "19 January 2017"
TH DJPEG 1 "18 March 2017"
.SH NAME
djpeg \- decompress a JPEG file to an image file
.SH SYNOPSIS
@@ -188,7 +188,7 @@ Set limit for amount of memory to use in processing large images. Value is
in thousands of bytes, or millions of bytes if "M" is attached to the
number. For example,
.B \-max 4m
selects 4000000 bytes. If more space is needed, temporary files will be used.
selects 4000000 bytes. If more space is needed, an error will occur.
.TP
.BI \-outfile " name"
Send output image to the named file, not to standard output.

4
java/TJBench.java
View File

@@ -1,5 +1,5 @@
/*
* Copyright (C)2009-2014, 2016 D. R. Commander. All Rights Reserved.
* Copyright (C)2009-2014, 2016-2017 D. R. Commander. All Rights Reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
@@ -582,8 +582,8 @@ class TJBench {
System.out.print("N/A N/A ");
jpegBuf = new byte[1][TJ.bufSize(_tilew, _tileh, subsamp)];
jpegSize = new int[1];
jpegBuf[0] = srcBuf;
jpegSize[0] = srcSize;
System.arraycopy(srcBuf, 0, jpegBuf[0], 0, srcSize);
}
if (w == tilew)

16
jmemnobs.c
View File

@@ -3,8 +3,8 @@
*
* This file was part of the Independent JPEG Group's software:
* Copyright (C) 1992-1996, Thomas G. Lane.
* It was modified by The libjpeg-turbo Project to include only code and
* information relevant to libjpeg-turbo.
* libjpeg-turbo Modifications:
* Copyright (C) 2017, D. R. Commander.
* For conditions of distribution and use, see the accompanying README.ijg
* file.
*
@@ -15,7 +15,6 @@
* This is very portable in the sense that it'll compile on almost anything,
* but you'd better have lots of main memory (or virtual memory) if you want
* to process big images.
* Note that the max_memory_to_use option is ignored by this implementation.
*/
#define JPEG_INTERNALS
@@ -66,14 +65,21 @@ jpeg_free_large (j_common_ptr cinfo, void *object, size_t sizeofobject)
/*
* This routine computes the total memory space available for allocation.
* Here we always say, "we got all you want bud!"
*/
GLOBAL(size_t)
jpeg_mem_available (j_common_ptr cinfo, size_t min_bytes_needed,
size_t max_bytes_needed, size_t already_allocated)
{
return max_bytes_needed;
if (cinfo->mem->max_memory_to_use) {
if (cinfo->mem->max_memory_to_use > already_allocated)
return cinfo->mem->max_memory_to_use - already_allocated;
else
return 0;
} else {
/* Here we always say, "we got all you want bud!" */
return max_bytes_needed;
}
}

4
jpegtran.1
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@@ -1,4 +1,4 @@
.TH JPEGTRAN 1 "19 January 2017"
.TH JPEGTRAN 1 "18 March 2017"
.SH NAME
jpegtran \- lossless transformation of JPEG files
.SH SYNOPSIS
@@ -227,7 +227,7 @@ Set limit for amount of memory to use in processing large images. Value is
in thousands of bytes, or millions of bytes if "M" is attached to the
number. For example,
.B \-max 4m
selects 4000000 bytes. If more space is needed, temporary files will be used.
selects 4000000 bytes. If more space is needed, an error will occur.
.TP
.BI \-outfile " name"
Send output image to the named file, not to standard output.

12
libjpeg.txt
View File

@@ -2981,13 +2981,6 @@ Some operating modes (eg, two-pass color quantization) require full-image
buffers. Such buffers are treated as "virtual arrays": only the current strip
need be in memory, and the rest can be swapped out to a temporary file.
If you use the simplest memory manager back end (jmemnobs.c), then no
temporary files are used; virtual arrays are simply malloc()'d. Images bigger
than memory can be processed only if your system supports virtual memory.
The other memory manager back ends support temporary files of various flavors
and thus work in machines without virtual memory. They may also be useful on
Unix machines if you need to process images that exceed available swap space.
When using temporary files, the library will make the in-memory buffers for
its virtual arrays just big enough to stay within a "maximum memory" setting.
Your application can set this limit by setting cinfo->mem->max_memory_to_use
@@ -3000,6 +2993,11 @@ that space allocated with alloc_small() is ignored, on the assumption that
it's too small to be worth worrying about; so a reasonable safety margin
should be left when setting max_memory_to_use.
NOTE: Unless you develop your own memory manager back end, then temporary files
will never be used. The back end provided in libjpeg-turbo (jmemnobs.c) simply
malloc()s and free()s virtual arrays, and an error occurs if the required
memory exceeds the limit specified in cinfo->mem->max_memory_to_use.
Memory usage
------------

1
simd/arm/jsimd.c
View File

@@ -2,6 +2,7 @@
* jsimd_arm.c
*
* Copyright 2009 Pierre Ossman <ossman@cendio.se> for Cendio AB
* Copyright (C) 2011, Nokia Corporation and/or its subsidiary(-ies).
* Copyright (C) 2009-2011, 2013-2014, 2016, D. R. Commander.
* Copyright (C) 2015-2016, Matthieu Darbois.
*

1
simd/arm64/jsimd.c
View File

@@ -2,6 +2,7 @@
* jsimd_arm64.c
*
* Copyright 2009 Pierre Ossman <ossman@cendio.se> for Cendio AB
* Copyright (C) 2011, Nokia Corporation and/or its subsidiary(-ies).
* Copyright (C) 2009-2011, 2013-2014, 2016, D. R. Commander.
* Copyright (C) 2015-2016, Matthieu Darbois.
*

24
structure.txt
View File

@@ -832,21 +832,19 @@ read_backing_store, manipulate a backing-store object
write_backing_store,
close_backing_store
On some systems there will be more than one type of backing-store object
(specifically, in MS-DOS a backing store file might be an area of extended
memory as well as a disk file). jpeg_open_backing_store is responsible for
choosing how to implement a given object. The read/write/close routines
are method pointers in the structure that describes a given object; this
lets them be different for different object types.
On some systems there will be more than one type of backing-store object.
jpeg_open_backing_store is responsible for choosing how to implement a given
object. The read/write/close routines are method pointers in the structure
that describes a given object; this lets them be different for different object
types.
It may be necessary to ensure that backing store objects are explicitly
released upon abnormal program termination. For example, MS-DOS won't free
extended memory by itself. To support this, we will expect the main program
or surrounding application to arrange to call self_destruct (typically via
jpeg_destroy) upon abnormal termination. This may require a SIGINT signal
handler or equivalent. We don't want to have the back end module install its
own signal handler, because that would pre-empt the surrounding application's
ability to control signal handling.
released upon abnormal program termination. To support this, we will expect
the main program or surrounding application to arrange to call self_destruct
(typically via jpeg_destroy) upon abnormal termination. This may require a
SIGINT signal handler or equivalent. We don't want to have the back end module
install its own signal handler, because that would pre-empt the surrounding
application's ability to control signal handling.
The IJG distribution includes several memory manager back end implementations.
Usually the same back end should be suitable for all applications on a given

10
tjbench.c
View File

@@ -1,5 +1,5 @@
/*
* Copyright (C)2009-2016 D. R. Commander. All Rights Reserved.
* Copyright (C)2009-2017 D. R. Commander. All Rights Reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
@@ -40,7 +40,7 @@
#define _throw(op, err) { \
printf("ERROR in line %d while %s:\n%s\n", __LINE__, op, err); \
retval=-1; goto bailout;}
retval=-1; goto bailout;}
#define _throwunix(m) _throw(m, strerror(errno))
#define _throwtj(m) _throw(m, tjGetErrorStr())
#define _throwbmp(m) _throw(m, bmpgeterr())
@@ -207,7 +207,7 @@ int decomp(unsigned char *srcbuf, unsigned char **jpegbuf,
(double)(w*h)/1000000.*(double)iter/elapsed);
if(doyuv)
{
printf("YUV Decode --> Frame rate:  %f fps\n",
printf("YUV Decode --> Frame rate: %f fps\n",
(double)iter/elapsedDecode);
printf(" Throughput: %f Megapixels/sec\n",
(double)(w*h)/1000000.*(double)iter/elapsedDecode);
@@ -668,7 +668,9 @@ int decompTest(char *filename)
{
if(quiet==1) printf("N/A N/A ");
jpegsize[0]=srcsize;
memcpy(jpegbuf[0], srcbuf, srcsize);
free(jpegbuf[0]);
jpegbuf[0]=srcbuf;
srcbuf=NULL;
}
if(w==tilew) _tilew=_w;

79
turbojpeg.c
View File

@@ -1,5 +1,5 @@
/*
* Copyright (C)2009-2016 D. R. Commander. All Rights Reserved.
* Copyright (C)2009-2017 D. R. Commander. All Rights Reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
@@ -772,13 +772,6 @@ DLLEXPORT int DLLCALL tjCompress2(tjhandle handle, const unsigned char *srcBuf,
|| jpegSubsamp<0 || jpegSubsamp>=NUMSUBOPT || jpegQual<0 || jpegQual>100)
_throw("tjCompress2(): Invalid argument");
if(setjmp(this->jerr.setjmp_buffer))
{
/* If we get here, the JPEG code has signaled an error. */
retval=-1;
goto bailout;
}
if(pitch==0) pitch=width*tjPixelSize[pixelFormat];
#ifndef JCS_EXTENSIONS
@@ -791,6 +784,16 @@ DLLEXPORT int DLLCALL tjCompress2(tjhandle handle, const unsigned char *srcBuf,
}
#endif
if((row_pointer=(JSAMPROW *)malloc(sizeof(JSAMPROW)*height))==NULL)
_throw("tjCompress2(): Memory allocation failure");
if(setjmp(this->jerr.setjmp_buffer))
{
/* If we get here, the JPEG code has signaled an error. */
retval=-1;
goto bailout;
}
cinfo->image_width=width;
cinfo->image_height=height;
@@ -807,8 +810,6 @@ DLLEXPORT int DLLCALL tjCompress2(tjhandle handle, const unsigned char *srcBuf,
return -1;
jpeg_start_compress(cinfo, TRUE);
if((row_pointer=(JSAMPROW *)malloc(sizeof(JSAMPROW)*height))==NULL)
_throw("tjCompress2(): Memory allocation failure");
for(i=0; i<height; i++)
{
if(flags&TJFLAG_BOTTOMUP)
@@ -888,13 +889,6 @@ DLLEXPORT int DLLCALL tjEncodeYUVPlanes(tjhandle handle,
if(subsamp!=TJSAMP_GRAY && (!dstPlanes[1] || !dstPlanes[2]))
_throw("tjEncodeYUVPlanes(): Invalid argument");
if(setjmp(this->jerr.setjmp_buffer))
{
/* If we get here, the JPEG code has signaled an error. */
retval=-1;
goto bailout;
}
if(pixelFormat==TJPF_CMYK)
_throw("tjEncodeYUVPlanes(): Cannot generate YUV images from CMYK pixels");
@@ -910,6 +904,13 @@ DLLEXPORT int DLLCALL tjEncodeYUVPlanes(tjhandle handle,
}
#endif
if(setjmp(this->jerr.setjmp_buffer))
{
/* If we get here, the JPEG code has signaled an error. */
retval=-1;
goto bailout;
}
cinfo->image_width=width;
cinfo->image_height=height;
@@ -986,6 +987,13 @@ DLLEXPORT int DLLCALL tjEncodeYUVPlanes(tjhandle handle,
}
}
if(setjmp(this->jerr.setjmp_buffer))
{
/* If we get here, the JPEG code has signaled an error. */
retval=-1;
goto bailout;
}
for(row=0; row<ph0; row+=cinfo->max_v_samp_factor)
{
(*cinfo->cconvert->color_convert)(cinfo, &row_pointer[row], tmpbuf, 0,
@@ -1160,6 +1168,13 @@ DLLEXPORT int DLLCALL tjCompressFromYUVPlanes(tjhandle handle,
}
}
if(setjmp(this->jerr.setjmp_buffer))
{
/* If we get here, the JPEG code has signaled an error. */
retval=-1;
goto bailout;
}
for(row=0; row<(int)cinfo->image_height;
row+=cinfo->max_v_samp_factor*DCTSIZE)
{
@@ -1438,6 +1453,12 @@ DLLEXPORT int DLLCALL tjDecompress2(tjhandle handle,
if((row_pointer=(JSAMPROW *)malloc(sizeof(JSAMPROW)
*dinfo->output_height))==NULL)
_throw("tjDecompress2(): Memory allocation failure");
if(setjmp(this->jerr.setjmp_buffer))
{
/* If we get here, the JPEG code has signaled an error. */
retval=-1;
goto bailout;
}
for(i=0; i<(int)dinfo->output_height; i++)
{
if(flags&TJFLAG_BOTTOMUP)
@@ -1660,6 +1681,13 @@ DLLEXPORT int DLLCALL tjDecodeYUVPlanes(tjhandle handle,
}
}
if(setjmp(this->jerr.setjmp_buffer))
{
/* If we get here, the JPEG code has signaled an error. */
retval=-1;
goto bailout;
}
for(row=0; row<ph0; row+=dinfo->max_v_samp_factor)
{
JDIMENSION inrow=0, outrow=0;
@@ -1840,6 +1868,13 @@ DLLEXPORT int DLLCALL tjDecompressToYUVPlanes(tjhandle handle,
}
}
if(setjmp(this->jerr.setjmp_buffer))
{
/* If we get here, the JPEG code has signaled an error. */
retval=-1;
goto bailout;
}
if(flags&TJFLAG_FASTUPSAMPLE) dinfo->do_fancy_upsampling=FALSE;
if(flags&TJFLAG_FASTDCT) dinfo->dct_method=JDCT_FASTEST;
dinfo->raw_data_out=TRUE;
@@ -2017,6 +2052,11 @@ DLLEXPORT int DLLCALL tjTransform(tjhandle handle,
else if(flags&TJFLAG_FORCESSE) putenv("JSIMD_FORCESSE=1");
else if(flags&TJFLAG_FORCESSE2) putenv("JSIMD_FORCESSE2=1");
if((xinfo=(jpeg_transform_info *)malloc(sizeof(jpeg_transform_info)*n))
==NULL)
_throw("tjTransform(): Memory allocation failure");
MEMZERO(xinfo, sizeof(jpeg_transform_info)*n);
if(setjmp(this->jerr.setjmp_buffer))
{
/* If we get here, the JPEG code has signaled an error. */
@@ -2026,11 +2066,6 @@ DLLEXPORT int DLLCALL tjTransform(tjhandle handle,
jpeg_mem_src_tj(dinfo, jpegBuf, jpegSize);
if((xinfo=(jpeg_transform_info *)malloc(sizeof(jpeg_transform_info)*n))
==NULL)
_throw("tjTransform(): Memory allocation failure");
MEMZERO(xinfo, sizeof(jpeg_transform_info)*n);
for(i=0; i<n; i++)
{
xinfo[i].transform=xformtypes[t[i].op];

35
usage.txt
View File

@@ -212,7 +212,7 @@ Switches for advanced users:
large images. Value is in thousands of bytes, or
millions of bytes if "M" is attached to the number.
For example, -max 4m selects 4000000 bytes. If more
space is needed, temporary files will be used.
space is needed, an error will occur.
-verbose Enable debug printout. More -v's give more printout.
or -debug Also, version information is printed at startup.
@@ -377,7 +377,7 @@ Switches for advanced users:
large images. Value is in thousands of bytes, or
millions of bytes if "M" is attached to the number.
For example, -max 4m selects 4000000 bytes. If more
space is needed, temporary files will be used.
space is needed, an error will occur.
-verbose Enable debug printout. More -v's give more printout.
or -debug Also, version information is printed at startup.
@@ -423,11 +423,6 @@ 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.
Two-pass color quantization requires a good deal of memory; on MS-DOS machines
it may run out of memory even with -maxmemory 0. In that case you can still
decompress, with some loss of image quality, by specifying -onepass for
one-pass quantization.
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.
@@ -435,24 +430,9 @@ decoders.
HINTS FOR BOTH PROGRAMS
If more space is needed than will fit in the available main memory (as
determined by -maxmemory), temporary files will be used. (MS-DOS versions
will try to get extended or expanded memory first.) The temporary files are
often rather large: in typical cases they occupy three bytes per pixel, for
example 3*800*600 = 1.44Mb for an 800x600 image. If you don't have enough
free disk space, leave out -progressive and -optimize (for cjpeg) or specify
-onepass (for djpeg).
On MS-DOS, the temporary files are created in the directory named by the TMP
or TEMP environment variable, or in the current directory if neither of those
exist. Amiga implementations put the temp files in the directory named by
JPEGTMP:, so be sure to assign JPEGTMP: to a disk partition with adequate free
space.
The default memory usage limit (-maxmemory) is set when the software is
compiled. If you get an "insufficient memory" error, try specifying a smaller
-maxmemory value, even -maxmemory 0 to use the absolute minimum space. You
may want to recompile with a smaller default value if this happens often.
If the memory needed by cjpeg or djpeg exceeds the limit specified by
-maxmemory, an error will occur. You can leave out -progressive and -optimize
(for cjpeg) or specify -onepass (for djpeg) to reduce memory usage.
On machines that have "environment" variables, you can define the environment
variable JPEGMEM to set the default memory limit. The value is specified as
@@ -460,11 +440,6 @@ described for the -maxmemory switch. JPEGMEM overrides the default value
specified when the program was compiled, and itself is overridden by an
explicit -maxmemory switch.
On MS-DOS machines, -maxmemory is the amount of main (conventional) memory to
use. (Extended or expanded memory is also used if available.) Most
DOS-specific versions of this software do their own memory space estimation
and do not need you to specify -maxmemory.
JPEGTRAN