djpeg.1


Log

Author Commit Date CI Message
DRC 5bc43c78 2017-11-13T21:01:53 Further partial image decompression fixes - Referring to 073b0e88a192adebbb479ee2456beb089d8b5de7 and #185, the reason why BMP and RLE didn't (and won't) work with partial image decompression is that the output engines for both formats maintain a whole-image buffer, which is used to reverse the order of scanlines. However, it was straightforward to add -crop support for GIF and Targa, which is useful for testing partial image decompression along with color quantization. - Such testing reproduced a bug reported by Mozilla (refer to PR #182) whereby jpeg_skip_scanlines() would segfault if color quantization was enabled. To fix this issue, read_and_discard_scanlines() now sets up a dummy quantize function in the same manner that it sets up a dummy color conversion function. Closes #182
DRC 073b0e88 2017-11-08T21:01:57 djpeg -crop: Exit gracefully with non-PPM formats ... and document that only PPM/PGM output images are supported with the -crop option for the moment. I investigated the possibility of supporting -crop with -bmp, but even after resetting the buffer dimensions, I still kept getting virtual array access errors. It seems that doing this the "right way" would require creating a re-initialization function for each image format's destination manager. I'm disinclined to do that right now, given that this feature was Google's baby (developed as a prerequisite for including libjpeg-turbo in Android), and the -crop option in djpeg is intended only as an example of how to use the partial image decompression API. Real-world applications would need to handle this in their own destination managers. It would probably be possible to make this work with Targa by employing a similar hack to the one we used with PPM, but Targa isn't popular enough to bother. Fixes #185
DRC da2a27ef 2017-03-18T16:15:14 Honor max_memory_to_use/JPEGMEM/-maxmemory This re-introduces a feature of the obsolete system-specific libjpeg memory managers-- namely the ability to limit the amount of main memory used by the library during decompression or multi-pass compression. This is mainly beneficial for two reasons: - Works around a 2 GB limit in libFuzzer - Allows security-sensitive applications to set a memory limit for the JPEG decoder so as to work around the progressive JPEG exploit (LJT-01-004) described here: http://www.libjpeg-turbo.org/pmwiki/uploads/About/TwoIssueswiththeJPEGStandard.pdf This commit also removes obsolete documentation regarding the MS-DOS memory manager (which itself was removed long ago) and changes the documentation of the -maxmemory switch and JPEGMEM environment variable to reflect the fact that backing stores are never used in libjpeg-turbo. Inspired by: https://github.com/caolanm/libjpeg-turbo/commit/066fee2e7d6834f24838bc1896aa38ca77209e3c Closes #143
DRC 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
DRC 83aeb7b2 2016-02-17T20:05:44 Wordsmith GIF limitations in cjpeg.1/djpeg.1
Guido Vollbeding a560e4b4 2016-01-17T00:00:00 The Independent JPEG Group's JPEG software v9b
Guido Vollbeding fc11193e 2014-01-19T00:00:00 The Independent JPEG Group's JPEG software v9a
Thomas G. Lane bc79e068 1995-08-02T00:00:00 The Independent JPEG Group's JPEG software v6
Thomas G. Lane a8b67c4f 1995-03-15T00:00:00 The Independent JPEG Group's JPEG software v5b
Thomas G. Lane 36a4cccc 1994-09-24T00:00:00 The Independent JPEG Group's JPEG software v5
Thomas G. Lane cc7150e2 1993-02-18T00:00:00 The Independent JPEG Group's JPEG software v4a
Thomas G. Lane 88aeed42 1992-12-10T00:00:00 The Independent JPEG Group's JPEG software v4
Thomas G. Lane 4a6b7303 1992-03-17T00:00:00 The Independent JPEG Group's JPEG software v3
Thomas G. Lane bd543f03 1991-12-13T00:00:00 The Independent JPEG Group's JPEG software v2
Guido Vollbeding 989630f7 2010-01-10T00:00:00 The Independent JPEG Group's JPEG software v8
Guido Vollbeding 5996a25e 2009-06-27T00:00:00 The Independent JPEG Group's JPEG software v7
Thomas G. Lane 5ead57a3 1998-03-27T00:00:00 The Independent JPEG Group's JPEG software v6b
DRC 7a7da946 2015-06-27T08:10:31 Add regression tests for jpeg_skip_scanlines(); change "stripe" to "strip" in djpeg; document -strip and -skip parameters in djpeg git-svn-id: svn+ssh://svn.code.sf.net/p/libjpeg-turbo/code/trunk@1587 632fc199-4ca6-4c93-a231-07263d6284db
DRC 9665f5e3 2014-11-22T04:04:38 Print the library version and exit whenever -version is passed to cjpeg, djpeg, or jpegtran. git-svn-id: svn+ssh://svn.code.sf.net/p/libjpeg-turbo/code/branches/1.4.x@1422 632fc199-4ca6-4c93-a231-07263d6284db
DRC 90d6c382 2014-05-12T09:08:39 Document -rgb option in djpeg man page; "gray-scale"="grayscale" git-svn-id: svn+ssh://svn.code.sf.net/p/libjpeg-turbo/code/branches/1.3.x@1293 632fc199-4ca6-4c93-a231-07263d6284db
DRC 05524e67 2014-05-11T23:14:43 Document the fact that the fast integer FDCT is not fully accelerated for quality levels above 97 + additional wordsmithing git-svn-id: svn+ssh://svn.code.sf.net/p/libjpeg-turbo/code/branches/1.3.x@1289 632fc199-4ca6-4c93-a231-07263d6284db
DRC 8940e6ca 2014-05-11T09:46:28 Provide a more thorough description of the trade-offs between the various DCT/IDCT algorithms, based on new resarch git-svn-id: svn+ssh://svn.code.sf.net/p/libjpeg-turbo/code/branches/1.3.x@1286 632fc199-4ca6-4c93-a231-07263d6284db
DRC ab70623e 2013-01-18T23:42:31 Implement in-memory source/destination managers even when not emulating the libjpeg v8 API/ABI git-svn-id: svn+ssh://svn.code.sf.net/p/libjpeg-turbo/code/trunk@913 632fc199-4ca6-4c93-a231-07263d6284db
DRC cf763c0c 2013-01-01T09:51:37 Further changes to the copyright/attribution notices to make it clear that our modified files are not part of the IJG's software. git-svn-id: svn+ssh://svn.code.sf.net/p/libjpeg-turbo/code/branches/1.2.x@876 632fc199-4ca6-4c93-a231-07263d6284db
DRC 03badeab 2013-01-01T09:49:47 Further changes to the copyright/attribution notices to make it clear that our modified files are not part of the IJG's software. git-svn-id: svn+ssh://svn.code.sf.net/p/libjpeg-turbo/code/trunk@875 632fc199-4ca6-4c93-a231-07263d6284db
DRC 27fb3fc5 2012-01-28T01:48:07 Support additional scaling factors when decompressing git-svn-id: svn+ssh://svn.code.sf.net/p/libjpeg-turbo/code/trunk@753 632fc199-4ca6-4c93-a231-07263d6284db
DRC 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
DRC 39ea562c 2010-10-12T01:55:31 Document new v7/v8 features; .doc = .txt git-svn-id: svn+ssh://svn.code.sf.net/p/libjpeg-turbo/code/trunk@252 632fc199-4ca6-4c93-a231-07263d6284db
Constantin Kaplinsky c8753072 2006-05-25T05:01:55 Migrating to new directory structure adopted from the RealVNC's source tree. More changes will follow. git-svn-id: svn+ssh://svn.code.sf.net/p/libjpeg-turbo/code/trunk@1 632fc199-4ca6-4c93-a231-07263d6284db