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Log

Author Commit Date CI Message
DRC be96fa0a 2023-12-14T13:18:20 Doc: Lossless JPEG clarifications - Clarify that lossless JPEG is slower than and doesn't compress as well as lossy JPEG. (That should be obvious, because "lossy" literally means that data is thrown away.) - Re-generate TurboJPEG C API documentation using Doxygen 1.9.8. - Clarify that setting the data_precision field in jpeg_compress_struct to 16 requires lossless mode. - Explain what the predictor selection value actually does. (Refer to Recommendation ITU-T T.81 (1992) | ISO/IEC 10918-1:1994, Section H.1.2.1.)
DRC 55d342c7 2023-11-16T15:36:47 TurboJPEG: Expose/extend hidden "max pixels" param TJPARAM_MAXPIXELS was previously hidden and used only for fuzz testing, but it is potentially useful for calling applications as well, particularly if they want to guard against excessive memory consumption by the tj3LoadImage*() functions. The parameter has also been extended to decompression and lossless transformation functions/methods, mainly as a convenience. (It was already possible for calling applications to impose their own JPEG image size limits by reading the JPEG header prior to decompressing or transforming the image.)
DRC df9dbff8 2023-11-11T12:25:03 TurboJPEG: New param to limit virt array mem usage This corresponds to max_memory_to_use in the jpeg_memory_mgr struct in the libjpeg API, except that the TurboJPEG parameter is specified in megabytes. Because this is 2023 and computers with less than 1 MB of memory are not a thing (at least not within the scope of libjpeg-turbo support), it isn't useful to allow a limit less than 1 MB to be specified. Furthermore, because TurboJPEG parameters are signed integers, if we allowed the memory limit to be specified in bytes, then it would be impossible to specify a limit larger than 2 GB on 64-bit machines. Because max_memory_to_use is a long signed integer, effectively we can specify a limit of up to 2 petabytes on 64-bit machines if the TurboJPEG parameter is specified in megabytes. (2 PB should be enough for anybody, right?) This commit also bumps the TurboJPEG API version to 3.0.1. Since the TurboJPEG API version no longer tracks the libjpeg-turbo version, it makes sense to increment the API revision number when adding constants, to increment the minor version number when adding functions, and to increment the major version number for a complete overhaul. This commit also removes the vestigial TJ_NUMPARAM macro, which was never defined because it proved unnecessary. Partially implements #735
DRC 4a831d6e 2023-06-30T10:15:40 turbojpeg.h: Make customFilter() proto match doc Closes #704
DRC fc881ebb 2023-03-09T20:55:43 TurboJPEG: Implement 4:4:1 chrominance subsampling This allows losslessly transposed or rotated 4:1:1 JPEG images to be losslessly cropped, partially decompressed, or decompressed to planar YUV images. Because tj3Transform() allows multiple lossless transformations to be chained together, all subsampling options need to have a corresponding transposed subsampling option. (This is why 4:4:0 was originally implemented as well.) Otherwise, the documentation would be technically incorrect. It says that images with unknown subsampling types cannot be losslessly cropped, partially decompressed, or decompressed to planar YUV images, but it doesn't say anything about images with known subsampling types whose subsampling type becomes unknown if the image is rotated or transposed. This is one of those situations in which it is easier to implement a feature that works around the problem than to document the problem. Closes #659
DRC fc01f467 2023-01-05T06:36:46 TurboJPEG 3 API overhaul (ChangeLog update forthcoming) - Prefix all function names with "tj3" and remove version suffixes from function names. (Future API overhauls will increment the prefix to "tj4", etc., thus retaining backward API/ABI compatibility without versioning each individual function.) - Replace stateless boolean flags (including TJ*FLAG_ARITHMETIC and TJ*FLAG_LOSSLESS, which were never released) with stateful integer parameters, the value of which persists between function calls. * Use parameters for the JPEG quality and subsampling as well, in order to eliminate the awkwardness of specifying function arguments that weren't relevant for lossless compression. * tj3DecompressHeader() now stores all relevant information about the JPEG image, including the width, height, subsampling type, entropy coding type, etc. in parameters rather than returning that information in its arguments. * TJ*FLAG_LIMITSCANS has been reimplemented as an integer parameter (TJ*PARAM_SCANLIMIT) that allows the number of scans to be specified. - Use the const keyword for all pointer arguments to unmodified buffers, as well as for both dimensions of 2D pointers. Addresses #395. - Use size_t rather than unsigned long to represent buffer sizes, since unsigned long is a 32-bit type on Windows. Addresses #24. - Return 0 from all buffer size functions if an error occurs, rather than awkwardly trying to return -1 in an unsigned data type. - Implement 12-bit and 16-bit data precision using dedicated compression, decompression, and image I/O functions/methods. * Suffix the names of all data-precision-specific functions with 8, 12, or 16. * Because the YUV functions are intended to be used for video, they are currently only implemented with 8-bit data precision, but they can be expanded to 12-bit data precision in the future, if necessary. * Extend TJUnitTest and TJBench to test 12-bit and 16-bit data precision, using a new -precision option. * Add appropriate regression tests for all of the above to the 'test' target. * Extend tjbenchtest to test 12-bit and 16-bit data precision, and add separate 'tjtest12' and 'tjtest16' targets. * BufferedImage I/O in the Java API is currently limited to 8-bit data precision, since the BufferedImage class does not straightforwardly support higher data precisions. * Extend the PPM reader to convert 12-bit and 16-bit PBMPLUS files to grayscale or CMYK pixels, as it already does for 8-bit files. - Properly accommodate lossless JPEG using dedicated parameters (TJ*PARAM_LOSSLESS, TJ*PARAM_LOSSLESSPSV, and TJ*PARAM_LOSSLESSPT), rather than using a flag and awkwardly repurposing the JPEG quality. Update TJBench to properly reflect whether a JPEG image is lossless. - Re-organize the TJBench usage screen. - Update the Java docs using Java 11, to improve the formatting and eliminate HTML frames. - Use the accurate integer DCT algorithm by default for both compression and decompression, since the "fast" algorithm is a legacy feature, it does not pass the ISO compliance tests, and it is not actually faster on modern x86 CPUs. * Remove the -accuratedct option from TJBench and TJExample. - Re-implement the 'tjtest' target using a CMake script that enables the appropriate tests, depending on the data precision and whether or not the Java API is part of the build. - Consolidate the C and Java versions of tjbenchtest into one script. - Consolidate the C and Java versions of tjexampletest into one script. - Combine all initialization functions into a single function (tj3Init()) that accepts an integer parameter specifying the subsystems to initialize. - Enable decompression scaling explicitly, using a new function/method (tj3SetScalingFactor()/TJDecompressor.setScalingFactor()), rather than implicitly using awkward "desired width"/"desired height" parameters. - Introduce a new macro/constant (TJUNSCALED/TJ.UNSCALED) that maps to a scaling factor of 1/1. - Implement partial image decompression, using a new function/method (tj3SetCroppingRegion()/TJDecompressor.setCroppingRegion()) and TJBench option (-crop). Extend tjbenchtest to test the new feature. Addresses #1. - Allow the JPEG colorspace to be specified explicitly when compressing, using a new parameter (TJ*PARAM_COLORSPACE). This allows JPEG images with the RGB and CMYK colorspaces to be created. - Remove the error/difference image feature from TJBench. Identical images to the ones that TJBench created can be generated using ImageMagick with 'magick composite <original_image> <output_image> -compose difference <diff_image>' - Handle JPEG images with unknown subsampling types. TJ*PARAM_SUBSAMP is set to TJ*SAMP_UNKNOWN (== -1) for such images, but they can still be decompressed fully into packed-pixel images or losslessly transformed (with the exception of lossless cropping.) They cannot be partially decompressed or decompressed into planar YUV images. Note also that TJBench, due to its lack of support for imperfect transforms, requires that the subsampling type be known when rotating, flipping, or transversely transposing an image. Addresses #436 - The Java version of TJBench now has identical functionality to the C version. This was accomplished by (somewhat hackishly) calling the TurboJPEG C image I/O functions through JNI and copying the pixels between the C heap and the Java heap. - Add parameters (TJ*PARAM_RESTARTROWS and TJ*PARAM_RESTARTBLOCKS) and a TJBench option (-restart) to allow the restart marker interval to be specified when compressing. Eliminate the undocumented TJ_RESTART environment variable. - Add a parameter (TJ*PARAM_OPTIMIZE), a transform option (TJ*OPT_OPTIMIZE), and a TJBench option (-optimize) to allow optimized baseline Huffman coding to be specified when compressing. Eliminate the undocumented TJ_OPTIMIZE environment variable. - Add parameters (TJ*PARAM_XDENSITY, TJ*PARAM_DENSITY, and TJ*DENSITYUNITS) to allow the pixel density to be specified when compressing or saving a Windows BMP image and to be queried when decompressing or loading a Windows BMP image. Addresses #77. - Refactor the fuzz targets to use the new API. * Extend decompression coverage to 12-bit and 16-bit data precision. * Replace the awkward cjpeg12 and cjpeg16 targets with proper TurboJPEG-based compress12, compress12-lossless, and compress16-lossless targets - Fix innocuous UBSan warnings uncovered by the new fuzzers. - Implement previous versions of the TurboJPEG API by wrapping the new functions (tested by running the 2.1.x versions of TJBench, via tjbenchtest, and TJUnitTest against the new implementation.) * Remove all JNI functions for deprecated Java methods and implement the deprecated methods using pure Java wrappers. It should be understood that backward API compatibility in Java applies only to the Java classes and that one cannot mix and match a JAR file from one version of libjpeg-turbo with a JNI library from another version. - tj3Destroy() now silently accepts a NULL handle. - tj3Alloc() and tj3Free() now return/accept void pointers, as malloc() and free() do. - The image I/O functions now accept a TurboJPEG instance handle, which is used to transmit/receive parameters and to receive error information. Closes #517
DRC d4589f4f 2023-01-14T18:07:53 Merge branch 'main' into dev
DRC 9a146f0f 2023-01-06T10:29:10 TurboJPEG: Numerous documentation improvements - Wordsmithing, formatting, and grammar tweaks - Various clarifications and corrections, including specifying whether a particular buffer or image is used as a source or destination - Accommodate/mention features that were introduced since the API documentation was created. - For clarity, use "packed-pixel" to describe uncompressed source/destination images that are not planar YUV. - Use "row" rather than "line" to refer to a single horizontal group of pixels or component values, for consistency with the libjpeg API documentation. (libjpeg also uses "scanline", which is a more archaic term.) - Use "alignment" rather than "padding" to refer to the number of bytes by which a row's width is evenly divisible. This consistifies the documention of the YUV functions and tjLoadImage(). ("Padding" typically refers to the number of bytes added to each row, which is not the same thing.) - Remove all references to "the underlying codec." Although the TurboJPEG API originated as a cross-platform wrapper for the Intel Integrated Performance Primitives, Sun mediaLib, QuickTime, and libjpeg, none of those TurboJPEG implementations has been maintained since 2009. Nothing would prevent someone from implementing the TurboJPEG API without libjpeg-turbo, but such an implementation would not necessarily have an "underlying codec." (It could be fully self-contained.) - Use "destination image" rather than "output image", for consistency, or describe the type of image that will be output. - Avoid the term "image buffer" and instead use "byte buffer" to refer to buffers that will hold JPEG images, or describe the type of image that will be contained in the buffer. (The Java documentation doesn't use "byte buffer", because the buffer arrays literally have "byte" in front of them, and since Java doesn't have pointers, it is not possible for mere mortals to store any other type of data in those arrays.) - C: Use "unified" to describe YUV images stored in a single buffer, for consistency with the Java documentation. - Use "planar YUV" rather than "YUV planar". Is is our convention to describe images using {component layout} {colorspace/pixel format} {image function}, e.g. "packed-pixel RGB source image" or "planar YUV destination image." - C: Document the TurboJPEG API version in which a particular function or macro was introduced, and reorder the backward compatibility function stubs in turbojpeg.h alphabetically by API version. - C: Use Markdown rather than HTML tags, where possible, in the Doxygen comments.
DRC 98ff1fd1 2022-11-21T20:57:39 TurboJPEG: Add lossless JPEG detection capability Add a new TurboJPEG C API function (tjDecompressHeader4()) and Java API method (TJDecompressor.getFlags()) that return the bitwise OR of any flags that are relevant to the JPEG image being decompressed (currently TJFLAG_PROGRESSIVE, TJFLAG_ARITHMETIC, TJFLAG_LOSSLESS, and their Java equivalents.) This allows a calling program to determine whether the image being decompressed is a lossless JPEG image, which means that the decompression scaling feature will not be available and that a full-sized destination buffer should be allocated. More specifically, this fixes a buffer overrun in TJBench, TJExample, and the decompress* fuzz targets that occurred when attempting (in vain) to decompress a lossless JPEG image with decompression scaling enabled.
DRC 25ccad99 2022-11-16T15:57:25 TurboJPEG: 8-bit lossless JPEG support
DRC 6002720c 2022-11-15T23:10:35 TurboJPEG: Opt. enable arithmetic entropy coding
DRC c81e91e8 2021-04-05T16:08:22 TurboJPEG: New flag for limiting prog JPEG scans This also fixes timeouts reported by OSS-Fuzz.
DRC 2d14fc2e 2020-10-01T14:35:46 Dox: Re-generate using Doxygen 1.8.20 This fixes a GitHub Dependabot alert regarding jquery.js. Fixes #421
DRC c0ca354e 2018-03-22T16:04:29 Label this release 2.0 instead of 1.6 This also pulls the formatting changes from 19c791cdac6df84418c66eb9d67cfa9703bc2461 into the TurboJPEG C API docs.
DRC dc4b9002 2017-11-16T20:43:12 TurboJPEG: Add alpha offset array/method Also, set the red/green/blue offsets for TJPF_GRAY to -1 rather than 0. It was undefined behavior for an application to use those arrays/methods with TJPF_GRAY anyhow, and this makes it easier for applications to programmatically detect whether a given pixel format has red, green, and blue components.
DRC aa745905 2017-11-16T18:09:07 TurboJPEG C API: Add BMP/PPM load/save functions The main justification for this is to provide new libjpeg-turbo users with a quick & easy way of developing a complete JPEG compression/decompression program without requiring them to build libjpeg-turbo from source (which was necessary in order to use the project-private bmp API) or to use external libraries. These new functions build upon significant enhancements to rdbmp.c, wrbmp.c, rdppm.c, and wrppm.c which allow those engines to convert directly between the native pixel format of the file and a pixel format ("colorspace" in libjpeg parlance) specified by the calling program. rdbmp.c and wrbmp.c have also been modified such that the calling program can choose to read or write image rows in the native (bottom-up) order of the file format, thus eliminating the need to use an inversion array. tjLoadImage() and tjSaveImage() leverage these new underlying features in order to significantly improve upon the performance of the old bmp API. Because these new functions cannot work without the libjpeg-turbo colorspace extensions, the libjpeg-compatible code in turbojpeg.c has been removed. That code was only there to serve as an example of how to use the TurboJPEG API on top of libjpeg, but more specific, buildable examples now exist in the https://github.com/libjpeg-turbo/ijg repository.
DRC dadebcd7 2017-06-28T11:43:08 TurboJPEG: Add "copy none", progressive xform opts Allow progressive entropy coding to be enabled on a transform-by-transform basis, and implement a new transform option for disabling the copying of markers. Closes #153
DRC aba6ae59 2017-06-27T13:24:08 TurboJPEG: Opt. enable progressive entropy coding Fulfills part of the feature request in #153. Also paves the way for SIMD-accelerated progressive Huffman coding (refer to #46.)
DRC d4092f6b 2017-06-27T10:54:21 TurboJPEG: Improve error handling - Provide a new C API function and TJException method that allows calling programs to query the severity of a compression/decompression/ transform error. - Provide a new flag that instructs the library to immediately stop compressing/decompressing/transforming if a warning is encountered. Fixes #151
DRC b9ab64d8 2017-05-11T21:02:29 TurboJPEG: Thread-safe error message retrieval Introduce a new C API function (tjGetErrorStr2()) that can be used to retrieve compression/decompression/transform error messages in a thread-safe (i.e. instance-specific) manner. Retrieving error messages from global functions is still thread-unsafe. Addresses a concern expressed in #151.
DRC 6fa14b37 2015-08-13T20:06:03 Declare source buffers in TurboJPEG C API as const This reassures the caller that the buffers will not be modified and also allows read-only buffers to be passed to the functions. Partially reverts 3947a19f25fc8186d3812dbcf8e70baea36ef652.
DRC 40dd3146 2014-08-17T12:23:49 Refactored YUVImage Java class so that it supports both unified YUV image buffers as well as separate YUV image planes; modified the JNI functions accordingly and added new helper functions to the TurboJPEG C API (tjPlaneWidth(), tjPlaneHeight(), tjPlaneSizeYUV()) to facilitate those modifications; changed potentially confusing "component width" and "component height" terms to "plane width" and "plane height" and modified variable names in turbojpeg.c to reflect this; numerous other documentation tweaks git-svn-id: svn+ssh://svn.code.sf.net/p/libjpeg-turbo/code/trunk@1360 632fc199-4ca6-4c93-a231-07263d6284db
DRC 9d77dad4 2014-08-12T15:06:30 Reformat TurboJPEG C API documentation to improve ease of maintenance and to make it more consistent with the javadoc formatting; fix minor error in tjCompressFromYUV() prototype. git-svn-id: svn+ssh://svn.code.sf.net/p/libjpeg-turbo/code/trunk@1344 632fc199-4ca6-4c93-a231-07263d6284db
DRC aecea388 2014-08-11T18:05:41 Extend the TurboJPEG C API to support handling YUV images stored in separate image planes instead of a unified buffer git-svn-id: svn+ssh://svn.code.sf.net/p/libjpeg-turbo/code/trunk@1343 632fc199-4ca6-4c93-a231-07263d6284db
DRC 34dca052 2014-02-28T09:17:14 Implement a YUV decode function in the TurboJPEG API, to be symmetric with tjEncodeYUV(). git-svn-id: svn+ssh://svn.code.sf.net/p/libjpeg-turbo/code/trunk@1132 632fc199-4ca6-4c93-a231-07263d6284db
DRC 07e982d9 2013-10-31T07:11:39 Deprecate and undocument the FORCE{MMX|SSE|SSE2|SSE3} flags. These were originally introduced in TurboJPEG/IPP as a way to override the automatic CPU selection in the underlying IPP codec, which was closed source. They are not meaningful anymore, since libjpeg-turbo provides environment variables to accomplish the same thing and since it no longer necessarily uses x86 SIMD code behind the scenes. git-svn-id: svn+ssh://svn.code.sf.net/p/libjpeg-turbo/code/trunk@1072 632fc199-4ca6-4c93-a231-07263d6284db
DRC 910a3572 2013-10-30T23:02:57 Extend the TurboJPEG C API to support compressing JPEG images from YUV planar images git-svn-id: svn+ssh://svn.code.sf.net/p/libjpeg-turbo/code/trunk@1067 632fc199-4ca6-4c93-a231-07263d6284db
DRC cd7c3e66 2013-08-23T02:49:25 Add CMYK support to the TurboJPEG C API git-svn-id: svn+ssh://svn.code.sf.net/p/libjpeg-turbo/code/trunk@1019 632fc199-4ca6-4c93-a231-07263d6284db
DRC 1f3635c4 2013-08-18T10:19:00 Add 4:1:1 subsampling support in the TurboJPEG C API git-svn-id: svn+ssh://svn.code.sf.net/p/libjpeg-turbo/code/trunk@1014 632fc199-4ca6-4c93-a231-07263d6284db
DRC bcda6834 2013-08-18T09:02:42 Upgrade to Doxygen 1.8.3.1; Add note regarding the fact that 4:4:0 lacks full SIMD support. git-svn-id: svn+ssh://svn.code.sf.net/p/libjpeg-turbo/code/branches/1.3.x@1007 632fc199-4ca6-4c93-a231-07263d6284db
DRC 71ccb39d 2013-08-18T09:00:15 Upgrade to Doxygen 1.8.3.1 git-svn-id: svn+ssh://svn.code.sf.net/p/libjpeg-turbo/code/branches/1.3.x@1006 632fc199-4ca6-4c93-a231-07263d6284db
DRC a4a48ed0 2013-08-18T08:47:03 Upgrade to Doxygen 1.8.3.1 git-svn-id: svn+ssh://svn.code.sf.net/p/libjpeg-turbo/code/trunk@1005 632fc199-4ca6-4c93-a231-07263d6284db
DRC 870fd8f1 2011-09-20T05:04:06 Add a couple of missing pages git-svn-id: svn+ssh://svn.code.sf.net/p/libjpeg-turbo/code/trunk@708 632fc199-4ca6-4c93-a231-07263d6284db
DRC f5467110 2011-09-20T05:02:19 Implement custom filter callback in Java git-svn-id: svn+ssh://svn.code.sf.net/p/libjpeg-turbo/code/trunk@707 632fc199-4ca6-4c93-a231-07263d6284db
DRC 7bf04d39 2011-09-17T00:18:31 Implement a custom DCT filter callback for lossless transforms git-svn-id: svn+ssh://svn.code.sf.net/p/libjpeg-turbo/code/trunk@703 632fc199-4ca6-4c93-a231-07263d6284db
DRC 9b28defe 2011-05-21T14:37:15 Completely refactored the TurboJPEG C API so that it uses pixel formats instead of the clunky pixel size + flags combination to define the pixel size and component order. tjCompress2() and tjTransform() can also now grow the JPEG buffer as needed, which can allow programs to save memory by not pre-allocating the "worst-case" buffer size calculated by TJBUFSIZE(). Converted API documentation to Doxygen. There is no legacy code remaining, so the refactored version of the library has been re-licensed under a BSD-style license. git-svn-id: svn+ssh://svn.code.sf.net/p/libjpeg-turbo/code/trunk@616 632fc199-4ca6-4c93-a231-07263d6284db