|
0fc7313e
|
2024-05-14T11:41:16
|
|
Don't traverse linked list when saving a marker
If the calling application invokes jpeg_save_markers() to save a
particular type of marker, then the save_marker() function will be
invoked for every marker of that type that is encountered. Previously,
only the head of the marker linked list was stored (in
jpeg_decompress_struct), so save_marker() had to traverse the entire
linked list before it could add a new marker to the tail of the list.
That caused CPU usage to grow exponentially with the number of markers.
Referring to #764, it is possible to create a JPEG image that contains
an excessive number of markers. The specific reproducer that uncovered
this issue is a specially-crafted 1-megabyte malformed JPEG image with
tens of thousands of APP1 markers, which required approximately 30
seconds of CPU time (on a modern Intel processor) to process. However,
it should also be possible to create a legitimate JPEG image that
reproduces the issue (such as an image with tens of thousands of
duplicate EXIF tags.)
This commit introduces a new pointer (in jpeg_decomp_master, in order to
preserve backward ABI compatibility) that is used to store the tail of
the marker linked list whenever a marker is added to it. Thus, it is no
longer necessary to traverse the list when adding a marker, and CPU
usage will grow linearly rather than exponentially with the number of
markers.
Fixes #764
|
|
|
bf9f319c
|
2023-06-29T16:07:42
|
|
Disallow color quantization with lossless decomp
Color quantization is a legacy feature that serves little or no purpose
with lossless JPEG images. 9f756bc67a84d4566bf74a0c2432aa55da404021
eliminated interaction issues between the lossless decompressor and the
color quantizers related to out-of-range 12-bit samples, but referring
to #701, other interaction issues apparently still exist. Such issues
are likely, given the fact that the color quantizers were not designed
with lossless decompression in mind.
This commit reverts 9f756bc67a84d4566bf74a0c2432aa55da404021, since the
issues it fixed are no longer relevant because of this commit and
2192560d74e6e6cf99dd05928885573be00a8208.
Fixed #672
Fixes #673
Fixes #674
Fixes #676
Fixes #677
Fixes #678
Fixes #679
Fixes #681
Fixes #683
Fixes #701
|
|
|
2241434e
|
2022-12-15T12:20:50
|
|
16-bit lossless JPEG support
|
|
|
3fb10c35
|
2022-11-16T12:18:45
|
|
Merge branch 'ijg.lossless' into dev
Lossless: Accommodate LJT colorspace/SIMD exts
In libjpeg-turbo, grayscale_convert() and null_convert() aren't the only
lossless color conversion algorithms. We can also losslessly convert
RGB to and from any of the extended RGB colorspaces, and some platforms
have SIMD-accelerated null color conversion.
This commit also disallows RGB565 output in lossless mode, and it moves
the IsExtRGB() macro from cdjpeg.h to jpegint.h and repurposes it to
make jinit_color_converter() and jinit_color_deconverter() more
readable.
|
|
|
af618ffe
|
2022-11-08T15:01:18
|
|
Clean up the lossless JPEG feature
- Rename jpeg_simple_lossless() to jpeg_enable_lossless() and modify the
function so that it stores the lossless parameters directly in the Ss
and Al fields of jpeg_compress_struct rather than using a scan script.
- Move the cjpeg -lossless switch into "Switches for advanced users".
- Document the libjpeg API and run-time features that are unavailable in
lossless mode, and ensure that all parameters, functions, and switches
related to unavailable features are ignored or generate errors in
lossless mode.
- Defer any action that depends on whether lossless mode is enabled
until jpeg_start_compress()/jpeg_start_decompress() is called.
- Document the purpose of the point transform value.
- "Codec" stands for coder/decoder, so it is a bit awkward to say
"lossless compression codec" and "lossless decompression codec".
Use "lossless compressor" and "lossless decompressor" instead.
- Restore backward API/ABI compatibility with libjpeg v6b:
* Move the new 'lossless' field from the exposed jpeg_compress_struct
and jpeg_decompress_struct structures into the opaque
jpeg_comp_master and jpeg_decomp_master structures, and allocate the
master structures in the body of jpeg_create_compress() and
jpeg_create_decompress().
* Remove the new 'process' field from jpeg_compress_struct and
jpeg_decompress_struct and replace it with the old
'progressive_mode' field and the new 'lossless' field.
* Remove the new 'data_unit' field from jpeg_compress_struct and
jpeg_decompress_struct and replace it with a locally-computed
data unit variable.
* Restore the names of macros and fields that refer to DCT blocks, and
document that they have a different meaning in lossless mode. (Most
of them aren't very meaningful in lossless mode anyhow.)
* Remove the new alloc_darray() method from jpeg_memory_mgr and
replace it with an internal macro that wraps the alloc_sarray()
method.
* Move the JDIFF* data types from jpeglib.h and jmorecfg.h into
jpegint.h.
* Remove the new 'codec' field from jpeg_compress_struct and
jpeg_decompress_struct and instead reuse the existing internal
coefficient control, forward/inverse DCT, and entropy
encoding/decoding structures for lossless compression/decompression.
* Repurpose existing error codes rather than introducing new ones.
(The new JERR_BAD_RESTART and JWRN_MUST_DOWNSCALE codes remain,
although JWRN_MUST_DOWNSCALE will probably be removed in
libjpeg-turbo, since we have a different way of handling multiple
data precisions.)
- Automatically enable lossless mode when a scan script with parameters
that are only valid for lossless mode is detected, and document the
use of scan scripts to generate lossless JPEG images.
- Move the sequential and shared Huffman routines back into jchuff.c and
jdhuff.c, and document that those routines are shared with jclhuff.c
and jdlhuff.c as well as with jcphuff.c and jdphuff.c.
- Move MAX_DIFF_BITS from jchuff.h into jclhuff.c, the only place where
it is used.
- Move the predictor and scaler code into jclossls.c and jdlossls.c.
- Streamline register usage in the [un]differencers (inspired by similar
optimizations in the color [de]converters.)
- Restructure the logic in a few places to reduce duplicated code.
- Ensure that all lossless-specific code is guarded by
C_LOSSLESS_SUPPORTED or D_LOSSLESS_SUPPORTED and that the library can
be built successfully if either or both of those macros is undefined.
- Remove all short forms of external names introduced by the lossless
JPEG patch. (These will not be needed by libjpeg-turbo, so there is
no use cleaning them up.)
- Various wordsmithing, formatting, and punctuation tweaks
- Eliminate various compiler warnings.
|
|
|
b56e8b28
|
2022-11-08T15:01:18
|
|
Clean up the lossless JPEG feature
- Rename jpeg_simple_lossless() to jpeg_enable_lossless() and modify the
function so that it stores the lossless parameters directly in the Ss
and Al fields of jpeg_compress_struct rather than using a scan script.
- Move the cjpeg -lossless switch into "Switches for advanced users".
- Document the libjpeg API and run-time features that are unavailable in
lossless mode, and ensure that all parameters, functions, and switches
related to unavailable features are ignored or generate errors in
lossless mode.
- Defer any action that depends on whether lossless mode is enabled
until jpeg_start_compress()/jpeg_start_decompress() is called.
- Document the purpose of the point transform value.
- "Codec" stands for coder/decoder, so it is a bit awkward to say
"lossless compression codec" and "lossless decompression codec".
Use "lossless compressor" and "lossless decompressor" instead.
- Restore backward API/ABI compatibility with libjpeg v6b:
* Move the new 'lossless' field from the exposed jpeg_compress_struct
and jpeg_decompress_struct structures into the opaque
jpeg_comp_master and jpeg_decomp_master structures, and allocate the
master structures in the body of jpeg_create_compress() and
jpeg_create_decompress().
* Remove the new 'process' field from jpeg_compress_struct and
jpeg_decompress_struct and replace it with the old
'progressive_mode' field and the new 'lossless' field.
* Remove the new 'data_unit' field from jpeg_compress_struct and
jpeg_decompress_struct and replace it with a locally-computed
data unit variable.
* Restore the names of macros and fields that refer to DCT blocks, and
document that they have a different meaning in lossless mode. (Most
of them aren't very meaningful in lossless mode anyhow.)
* Remove the new alloc_darray() method from jpeg_memory_mgr and
replace it with an internal macro that wraps the alloc_sarray()
method.
* Move the JDIFF* data types from jpeglib.h and jmorecfg.h into
jpegint.h.
* Remove the new 'codec' field from jpeg_compress_struct and
jpeg_decompress_struct and instead reuse the existing internal
coefficient control, forward/inverse DCT, and entropy
encoding/decoding structures for lossless compression/decompression.
* Repurpose existing error codes rather than introducing new ones.
(The new JERR_BAD_RESTART and JWRN_MUST_DOWNSCALE codes remain,
although JWRN_MUST_DOWNSCALE will probably be removed in
libjpeg-turbo, since we have a different way of handling multiple
data precisions.)
- Automatically enable lossless mode when a scan script with parameters
that are only valid for lossless mode is detected, and document the
use of scan scripts to generate lossless JPEG images.
- Move the sequential and shared Huffman routines back into jchuff.c and
jdhuff.c, and document that those routines are shared with jclhuff.c
and jdlhuff.c as well as with jcphuff.c and jdphuff.c.
- Move MAX_DIFF_BITS from jchuff.h into jclhuff.c, the only place where
it is used.
- Move the predictor and scaler code into jclossls.c and jdlossls.c.
- Streamline register usage in the [un]differencers (inspired by similar
optimizations in the color [de]converters.)
- Restructure the logic in a few places to reduce duplicated code.
- Ensure that all lossless-specific code is guarded by
C_LOSSLESS_SUPPORTED or D_LOSSLESS_SUPPORTED and that the library can
be built successfully if either or both of those macros is undefined.
- Remove all short forms of external names introduced by the lossless
JPEG patch. (These will not be needed by libjpeg-turbo, so there is
no use cleaning them up.)
- Various wordsmithing, formatting, and punctuation tweaks
- Eliminate various compiler warnings.
|
|
|
97772cba
|
2022-11-14T15:36:25
|
|
Merge branch 'ijg.lossless' into dev
Refer to #402
|
|
|
217d1a75
|
2022-11-08T15:01:18
|
|
Clean up the lossless JPEG feature
- Rename jpeg_simple_lossless() to jpeg_enable_lossless() and modify the
function so that it stores the lossless parameters directly in the Ss
and Al fields of jpeg_compress_struct rather than using a scan script.
- Move the cjpeg -lossless switch into "Switches for advanced users".
- Document the libjpeg API and run-time features that are unavailable in
lossless mode, and ensure that all parameters, functions, and switches
related to unavailable features are ignored or generate errors in
lossless mode.
- Defer any action that depends on whether lossless mode is enabled
until jpeg_start_compress()/jpeg_start_decompress() is called.
- Document the purpose of the point transform value.
- "Codec" stands for coder/decoder, so it is a bit awkward to say
"lossless compression codec" and "lossless decompression codec".
Use "lossless compressor" and "lossless decompressor" instead.
- Restore backward API/ABI compatibility with libjpeg v6b:
* Move the new 'lossless' field from the exposed jpeg_compress_struct
and jpeg_decompress_struct structures into the opaque
jpeg_comp_master and jpeg_decomp_master structures, and allocate the
master structures in the body of jpeg_create_compress() and
jpeg_create_decompress().
* Remove the new 'process' field from jpeg_compress_struct and
jpeg_decompress_struct and replace it with the old
'progressive_mode' field and the new 'lossless' field.
* Remove the new 'data_unit' field from jpeg_compress_struct and
jpeg_decompress_struct and replace it with a locally-computed
data unit variable.
* Restore the names of macros and fields that refer to DCT blocks, and
document that they have a different meaning in lossless mode. (Most
of them aren't very meaningful in lossless mode anyhow.)
* Remove the new alloc_darray() method from jpeg_memory_mgr and
replace it with an internal macro that wraps the alloc_sarray()
method.
* Move the JDIFF* data types from jpeglib.h and jmorecfg.h into
jpegint.h.
* Remove the new 'codec' field from jpeg_compress_struct and
jpeg_decompress_struct and instead reuse the existing internal
coefficient control, forward/inverse DCT, and entropy
encoding/decoding structures for lossless compression/decompression.
* Repurpose existing error codes rather than introducing new ones.
(The new JERR_BAD_RESTART and JWRN_MUST_DOWNSCALE codes remain,
although JWRN_MUST_DOWNSCALE will probably be removed in
libjpeg-turbo, since we have a different way of handling multiple
data precisions.)
- Automatically enable lossless mode when a scan script with parameters
that are only valid for lossless mode is detected, and document the
use of scan scripts to generate lossless JPEG images.
- Move the sequential and shared Huffman routines back into jchuff.c and
jdhuff.c, and document that those routines are shared with jclhuff.c
and jdlhuff.c as well as with jcphuff.c and jdphuff.c.
- Move MAX_DIFF_BITS from jchuff.h into jclhuff.c, the only place where
it is used.
- Move the predictor and scaler code into jclossls.c and jdlossls.c.
- Streamline register usage in the [un]differencers (inspired by similar
optimizations in the color [de]converters.)
- Restructure the logic in a few places to reduce duplicated code.
- Ensure that all lossless-specific code is guarded by
C_LOSSLESS_SUPPORTED or D_LOSSLESS_SUPPORTED and that the library can
be built successfully if either or both of those macros is undefined.
- Remove all short forms of external names introduced by the lossless
JPEG patch. (These will not be needed by libjpeg-turbo, so there is
no use cleaning them up.)
- Various wordsmithing, formatting, and punctuation tweaks
- Eliminate various compiler warnings.
|
|
|
b5a9ef64
|
2022-11-13T13:00:26
|
|
Don't allow 12-bit JPEG support to be disabled
In libjpeg-turbo 2.1.x and prior, the WITH_12BIT CMake variable was used
to enable 12-bit JPEG support at compile time, because the libjpeg API
library could not handle multiple JPEG data precisions at run time. The
initial approach to handling multiple JPEG data precisions at run time
(7fec5074f962b20ed00b4f5da4533e1e8d4ed8ac) created a whole new API,
library, and applications for 12-bit data precision, so it made sense to
repurpose WITH_12BIT to allow 12-bit data precision to be disabled.
e8b40f3c2ba187ba95c13c3e8ce21c8534256df7 made it so that the libjpeg API
library can handle multiple JPEG data precisions at run time via a
handful of straightforward API extensions. Referring to
6c2bc901e27b047440ed46920c4d3f0480b48268, it hasn't been possible to
build libjpeg-turbo with both forward and backward libjpeg API/ABI
compatibility since libjpeg-turbo 1.4.x. Thus, whereas we retain full
backward API/ABI compatibility with libjpeg v6b-v8, forward libjpeg
API/ABI compatibility ceased being realistic years ago, so it no longer
makes sense to provide compile-time options that give a false sense of
forward API/ABI compatibility by allowing some (but not all) of our
libjpeg API extensions to be disabled. Such options are difficult to
maintain and clutter the code with #ifdefs.
|
|
|
e8b40f3c
|
2022-11-01T21:45:39
|
|
Vastly improve 12-bit JPEG integration
The Gordian knot that 7fec5074f962b20ed00b4f5da4533e1e8d4ed8ac attempted
to unravel was caused by the fact that there are several
data-precision-dependent (JSAMPLE-dependent) fields and methods in the
exposed libjpeg API structures, and if you change the exposed libjpeg
API structures, then you have to change the whole API. If you change
the whole API, then you have to provide a whole new library to support
the new API, and that makes it difficult to support multiple data
precisions in the same application. (It is not impossible, as example.c
demonstrated, but using data-precision-dependent libjpeg API structures
would have made the cjpeg, djpeg, and jpegtran source code hard to read,
so it made more sense to build, install, and package 12-bit-specific
versions of those applications.)
Unfortunately, the result of that initial integration effort was an
unreadable and unmaintainable mess, which is a problem for a library
that is an ISO/ITU-T reference implementation. Also, as I dug into the
problem of lossless JPEG support, I realized that 16-bit lossless JPEG
images are a thing, and supporting yet another version of the libjpeg
API just for those images is untenable.
In fact, however, the touch points for JSAMPLE in the exposed libjpeg
API structures are minimal:
- The colormap and sample_range_limit fields in jpeg_decompress_struct
- The alloc_sarray() and access_virt_sarray() methods in
jpeg_memory_mgr
- jpeg_write_scanlines() and jpeg_write_raw_data()
- jpeg_read_scanlines() and jpeg_read_raw_data()
- jpeg_skip_scanlines() and jpeg_crop_scanline()
(This is subtle, but both of those functions use JSAMPLE-dependent
opaque structures behind the scenes.)
It is much more readable and maintainable to provide 12-bit-specific
versions of those six top-level API functions and to document that the
aforementioned methods and fields must be type-cast when using 12-bit
samples. Since that eliminates the need to provide a 12-bit-specific
version of the exposed libjpeg API structures, we can:
- Compile only the precision-dependent libjpeg modules (the
coefficient buffer controllers, the colorspace converters, the
DCT/IDCT managers, the main buffer controllers, the preprocessing
and postprocessing controller, the downsampler and upsamplers, the
quantizers, the integer DCT methods, and the IDCT methods) for
multiple data precisions.
- Introduce 12-bit-specific methods into the various internal
structures defined in jpegint.h.
- Create precision-independent data type, macro, method, field, and
function names that are prefixed by an underscore, and use an
internal header to convert those into precision-dependent data
type, macro, method, field, and function names, based on the value
of BITS_IN_JSAMPLE, when compiling the precision-dependent libjpeg
modules.
- Expose precision-dependent jinit*() functions for each of the
precision-dependent libjpeg modules.
- Abstract the precision-dependent libjpeg modules by calling the
appropriate precision-dependent jinit*() function, based on the
value of cinfo->data_precision, from top-level libjpeg API
functions.
|
|
|
ec6e451d
|
2022-10-21T16:45:25
|
|
Lossless JPEG support: Add copyright attributions
Referring to
https://github.com/libjpeg-turbo/libjpeg-turbo/issues/402#issuecomment-768348440
and
https://github.com/libjpeg-turbo/libjpeg-turbo/issues/402#issuecomment-770221584
Ken Murchison clarified that it was his intent to release the lossless
JPEG patch under the IJG License and that adding his name to the
copyright headers would be sufficient to acknowledge that any
derivatives are based on his work.
|
|
|
2df43f51
|
2022-10-21T16:30:49
|
|
Lossless JPEG support: Fix build
(Modern compilers require function prototypes.)
|
|
2e8360e0
|
1999-04-27T00:00:00
|
|
IJG's JPEG software v6b with lossless JPEG support
Patch obtained from:
https://sourceforge.net/projects/jpeg/files/ftp.oceana.com
Author date taken from original announcement and timestamp of patch
tarball:
https://groups.google.com/g/comp.protocols.dicom/c/rrkP8BxoMRk/m/Ij4dfprggp8J
|
|
|
7fec5074
|
2022-03-08T12:34:11
|
|
Support 8-bit & 12-bit JPEGs using the same build
Partially implements #199
This commit also implements a request from #178 (the ability to compile
the libjpeg example as a standalone program.)
|
|
|
17297239
|
2022-01-06T09:17:30
|
|
Eliminate non-ANSI C compatibility macros
libjpeg-turbo has never supported non-ANSI C compilers. Per the spec,
ANSI C compilers must have locale.h, stddef.h, stdlib.h, memset(),
memcpy(), unsigned char, and unsigned short. They must also handle
undefined structures.
|
|
a72816ed
|
2021-07-16T09:37:06
|
|
Use uintptr_t, if avail, for pointer-to-int casts
Although sizeof(void *) == sizeof(size_t) for all architectures that are
currently supported by libjpeg-turbo, such is not guaranteed by the C
standard. Specifically, CHERI-enabled architectures (e.g. CHERI-RISC-V
or Arm's Morello) use capability pointers that are twice the size of
size_t (128 bits for Morello and RV64), so casting to size_t strips the
upper bits of the pointer (including the validity bit) and makes it
non-deferenceable, as indicated by the following compiler warning:
warning: cast from provenance-free integer type to pointer type will
give pointer that can not be dereferenced
[-Werror,-Wcheri-capability-misuse]
cvalue = values = (JCOEF *)PAD((size_t)values_unaligned, 16);
Ignoring this warning results in a run-time crash. Casting pointers to
uintptr_t, if it is available, avoids this problem, since uintptr_t is
defined as an unsigned integer type that can hold a pointer value.
Since C89 compatibility is still necessary in libjpeg-turbo, this commit
introduces a new typedef for pointer-to-integer casts that uses a
GNU-specific extension available in GCC 4.6+ and Clang 3.0+ and falls
back to using size_t if the extension is unavailable. The only other
options would require C99 or Clang-specific builtins.
Closes #538
|
|
9fc018fd
|
2020-01-12T00:00:00
|
|
The Independent JPEG Group's JPEG software v9d
|
|
|
96e4e7eb
|
2018-01-14T00:00:00
|
|
The Independent JPEG Group's JPEG software v9c
|
|
|
42825b68
|
2019-11-07T14:03:23
|
|
Fault-tolerant multi-scan block smoothing
This commit modifies the behavior of the block smoothing algorithm in
the libjpeg API library so that, if a scan in a multi-scan JPEG image is
incomplete (due to premature termination of the image stream), the block
smoothing parameters from the previous (complete) scan are used to
smooth any iMCU rows that the incomplete scan does not contain.
Closes #343
|
|
|
293263c3
|
2018-03-17T15:14:35
|
|
Format preprocessor macros more consistently
Within the libjpeg API code, it seems to be more the convention than not
to separate the macro name and value by two or more spaces, which
improves general readability. Making this consistent across all of
libjpeg-turbo is less about my individual preferences and more about
making it easy to automatically detect variations from our chosen
formatting convention. I intend to release the script I'm using to
validate this stuff, once it matures and stabilizes a bit.
|
|
|
19c791cd
|
2018-03-08T10:55:20
|
|
Improve code formatting consistency
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.
|
|
|
077e5bb4
|
2016-09-08T21:49:02
|
|
Fix out-of-bounds write in partial decomp. feature
Reported by Clang UBSan (refer to
https://bugzilla.mozilla.org/show_bug.cgi?id=1301252 for test image.)
This appears to be a legitimate bug introduced by
3ab68cf563f6edc2608c085f5c8b2d5d5c61157e. Any component array, such
as first_MCU_col and last_MCU_col, should always be able to accommodate
MAX_COMPONENTS values. The aforementioned test image had 8 components,
which was not enough to make the out-of-bounds write bust out of the
jpeg_decomp_master struct (and fortunately the memory after last_MCU_col
is an integer used as a boolean, so stomping on it will do nothing other
than change the decoder state.) I crafted another special image that
has 10 components (the maximum allowable), but that was apparently not
enough to bust out of the allocated memory, either. Thus, it is
posited that the security threat posed by this bug is either extremely
minimal or non-existent.
|
|
|
123f7258
|
2016-05-24T10:23:56
|
|
Format copyright headers more consistently
The IJG convention is to format copyright notices as:
Copyright (C) YYYY, Owner.
We try to maintain this convention for any code that is part of the
libjpeg API library (with the exception of preserving the copyright
notices from Cendio's code verbatim, since those predate
libjpeg-turbo.)
Note that the phrase "All Rights Reserved" is no longer necessary, since
all Buenos Aires Convention signatories signed onto the Berne Convention
in 2000. However, our convention is to retain this phrase for any files
that have a self-contained copyright header but to leave it off of any
files that refer to another file for conditions of distribution and use.
For instance, all of the non-SIMD files in the libjpeg API library refer
to README.ijg, and the copyright message in that file contains "All
Rights Reserved", so it is unnecessary to add it to the individual
files.
The TurboJPEG code retains my preferred formatting convention for
copyright notices, which is based on that of VirtualGL (where the
TurboJPEG API originated.)
|
|
|
3ab68cf5
|
2016-02-19T18:32:10
|
|
libjpeg API: Partial scanline decompression
This, in combination with the existing jpeg_skip_scanlines() function,
provides the ability to crop the image both horizontally and vertically
while decompressing (certain restrictions apply-- see libjpeg.txt.)
This also cleans up the documentation of the line skipping feature and
removes the "strip decompression" feature from djpeg, since the new
cropping feature is a superset of it.
Refer to #34 for discussion.
Closes #34
|
|
|
bd49803f
|
2016-02-19T08:53:33
|
|
Use consistent/modern code formatting for pointers
The convention used by libjpeg:
type * variable;
is not very common anymore, because it looks too much like
multiplication. Some (particularly C++ programmers) prefer to tuck the
pointer symbol against the type:
type* variable;
to emphasize that a pointer to a type is effectively a new type.
However, this can also be confusing, since defining multiple variables
on the same line would not work properly:
type* variable1, variable2; /* Only variable1 is actually a
pointer. */
This commit reformats the entirety of the libjpeg-turbo code base so
that it uses the same code formatting convention for pointers that the
TurboJPEG API code uses:
type *variable1, *variable2;
This seems to be the most common convention among C programmers, and
it is the convention used by other codec libraries, such as libpng and
libtiff.
|
|
|
fc11193e
|
2014-01-19T00:00:00
|
|
The Independent JPEG Group's JPEG software v9a
|
|
|
1e32fe31
|
2015-10-14T17:32:39
|
|
Replace INT32 with a new internal datatype (JLONG)
These days, INT32 is a commonly-defined datatype in system headers. We
cannot eliminate the definition of that datatype from jmorecfg.h, since
the INT32 typedef has technically been part of the libjpeg API since
version 5 (1994.) However, using INT32 internally is risky, because the
inclusion of a particular header (Xmd.h, for instance) could change the
definition of INT32 from long to int on 64-bit platforms and thus change
the internal behavior of libjpeg-turbo in unexpected ways (for instance,
failing to correctly set __INT32_IS_ACTUALLY_LONG to match the INT32
typedef-- perhaps as a result of including the wrong version of
jpeglib.h-- could cause libjpeg-turbo to produce incorrect results.)
The library has always been built in environments in which INT32 is
effectively long (on Windows, long is always 32-bit, so effectively it's
the same as int), so it makes sense to turn INT32 into an explicitly
long datatype. This ensures that libjpeg-turbo will always behave
consistently, regardless of the headers included at compile time.
Addresses a concern expressed in #26.
|
|
|
7e3acc0e
|
2015-10-10T10:25:46
|
|
Rename README, LICENSE, BUILDING text files
The IJG README file has been renamed to README.ijg, in order to avoid
confusion (many people were assuming that that was our project's README
file and weren't reading README-turbo.txt) and to lay the groundwork for
markdown versions of the libjpeg-turbo README and build instructions.
|
|
|
8e9cef2e
|
2015-09-21T12:57:41
|
|
Fix various issues reported by the UB sanitizers
Most of these involved left shifting a negative number, which is
technically undefined (although every modern compiler I'm aware of
will implement this by treating the signed integer as a 2's complement
unsigned integer-- the LEFT_SHIFT() macro just makes this behavior
explicit in order to shut up ubsan.) This also fixes a couple of
non-issues in the entropy codecs, whereby the sanitizer reported an
out-of-bounds index in the 4th argument of jpeg_make_d_derived_tbl().
In those cases, the index was actually out of bounds (caused by a
malformed JPEG image), but jpeg_make_d_derived_tbl() would have caught
the error and aborted prior to actually using the invalid address. Here
again, the fix was to make our intentions explicit so as to shut up
ubsan.
|
|
a2e6a9dd
|
2006-02-04T00:00:00
|
|
IJG R6b with x86SIMD V1.02
Independent JPEG Group's JPEG software release 6b
with x86 SIMD extension for IJG JPEG library version 1.02
|
|
489583f5
|
1996-02-07T00:00:00
|
|
The Independent JPEG Group's JPEG software v6a
|
|
|
bc79e068
|
1995-08-02T00:00:00
|
|
The Independent JPEG Group's JPEG software v6
|
|
|
a8b67c4f
|
1995-03-15T00:00:00
|
|
The Independent JPEG Group's JPEG software v5b
|
|
|
36a4cccc
|
1994-09-24T00:00:00
|
|
The Independent JPEG Group's JPEG software v5
|
|
1e247ac8
|
1998-03-28T00:00:00
|
|
The Independent JPEG Group's JPEG software v6b with arithmetic coding support
|
|
|
5829cb23
|
2012-01-15T00:00:00
|
|
The Independent JPEG Group's JPEG software v8d
|
|
989630f7
|
2010-01-10T00:00:00
|
|
The Independent JPEG Group's JPEG software v8
|
|
|
5996a25e
|
2009-06-27T00:00:00
|
|
The Independent JPEG Group's JPEG software v7
|
|
|
5ead57a3
|
1998-03-27T00:00:00
|
|
The Independent JPEG Group's JPEG software v6b
|
|
|
03e755bb
|
2015-07-21T17:36:18
|
|
Further improvements to partial image decoding
When using context-based upsampling, use a dummy color conversion
routine instead of a dummy row buffer. This improves performance
(since the actual color conversion routine no longer has to be called),
and it also fixes valgrind errors when decompressing to RGB565.
Valgrind previously complained, because using the RGB565 color
converter with the dummy row buffer was causing a table lookup with
undefined indices.
|
|
eb32cc1e
|
2015-06-25T03:44:36
|
|
Add a new libjpeg API function (jpeg_skip_scanlines()) to allow for partially decoding a JPEG image.
git-svn-id: svn+ssh://svn.code.sf.net/p/libjpeg-turbo/code/trunk@1582 632fc199-4ca6-4c93-a231-07263d6284db
|
|
|
5033f3e1
|
2014-05-18T18:33:44
|
|
Remove MS-DOS code and information, and adjust copyright headers to reflect the removal of features in r1307 and r1308. libjpeg-turbo has never supported MS-DOS, nor is it even possible for us to do so.
git-svn-id: svn+ssh://svn.code.sf.net/p/libjpeg-turbo/code/trunk@1312 632fc199-4ca6-4c93-a231-07263d6284db
|
|
|
bc56b754
|
2014-05-16T10:43:44
|
|
Get rid of the HAVE_PROTOTYPES configuration option, as well as the related JMETHOD and JPP macros. libjpeg-turbo has never supported compilers that don't handle prototypes. Doing so requires ansi2knr, which isn't even supported in the IJG code anymore.
git-svn-id: svn+ssh://svn.code.sf.net/p/libjpeg-turbo/code/trunk@1308 632fc199-4ca6-4c93-a231-07263d6284db
|
|
|
52ded876
|
2014-05-15T20:30:16
|
|
Remove all of the NEED_SHORT_EXTERNAL_NAMES stuff. There is scant information available as to which linkers ever had a 15-character global symbol name limit. AFAICT, it might have been a VMS and/or a.out BSD thing, but none of those platforms have ever been supported by libjpeg-turbo (nor are such systems supported by other open source libraries of this nature.)
git-svn-id: svn+ssh://svn.code.sf.net/p/libjpeg-turbo/code/trunk@1307 632fc199-4ca6-4c93-a231-07263d6284db
|
|
|
333e9187
|
2014-05-12T00:34:08
|
|
Use 2-space indentation for the enums, to be consistent with the structs
git-svn-id: svn+ssh://svn.code.sf.net/p/libjpeg-turbo/code/branches/1.3.x@1291 632fc199-4ca6-4c93-a231-07263d6284db
|
|
|
b7753510
|
2014-05-11T09:36:25
|
|
Convert tabs to spaces in the libjpeg code and the SIMD code (TurboJPEG retains the use of tabs for historical reasons. They were annoying in the libjpeg code primarily because they were not consistently used and because they were used to format as well as indent the code. In the case of TurboJPEG, tabs are used just to indent the code, so even if the editor assumes a different tab width, the code will still be readable.)
git-svn-id: svn+ssh://svn.code.sf.net/p/libjpeg-turbo/code/branches/1.3.x@1285 632fc199-4ca6-4c93-a231-07263d6284db
|
|
|
e5eaf374
|
2014-05-09T18:00:32
|
|
Convert tabs to spaces in the libjpeg code and the SIMD code (TurboJPEG retains the use of tabs for historical reasons. They were annoying in the libjpeg code primarily because they were not consistently used and because they were used to format as well as indent the code. In the case of TurboJPEG, tabs are used just to indent the code, so even if the editor assumes a different tab width, the code will still be readable.)
git-svn-id: svn+ssh://svn.code.sf.net/p/libjpeg-turbo/code/trunk@1278 632fc199-4ca6-4c93-a231-07263d6284db
|
|
|
a8eabfeb
|
2011-03-29T04:58:40
|
|
Create local round up function for jmemmgr.c so we can revert the original argument types of jround_up() without breaking the build on 64-bit Windows.
git-svn-id: svn+ssh://svn.code.sf.net/p/libjpeg-turbo/code/branches/1.1.x@539 632fc199-4ca6-4c93-a231-07263d6284db
|
|
|
66f97e68
|
2010-11-23T05:49:54
|
|
Support arithmetic encoding and decoding
git-svn-id: svn+ssh://svn.code.sf.net/p/libjpeg-turbo/code/trunk@299 632fc199-4ca6-4c93-a231-07263d6284db
|
|
|
04899094
|
2010-02-26T23:01:19
|
|
Bleepin' Windows uses LLP64, not LP64
git-svn-id: svn+ssh://svn.code.sf.net/p/libjpeg-turbo/code/trunk@158 632fc199-4ca6-4c93-a231-07263d6284db
|