README.md


Log

Author Commit Date CI Message
DRC 3d1d68cf 2023-10-04T13:20:38 README.md: Mention 4:4:0 math. incomp. vs. jpeg-6b libjpeg-turbo implements 4:4:0 "fancy" (smooth) upsampling, which is enabled by default when decompressing JPEG images that use 4:4:0 chrominance subsampling. libjpeg did not and does not implement fancy 4:4:0 upsampling.
DRC 926f1f3d 2023-07-05T12:41:32 README.md: Include GitHub Sponsors link/button Closes #706
DRC 762f8b4f 2023-07-05T10:55:07 Doc: Mention that we are a JPEG ref implementation
DRC 6b9e3b04 2023-06-19T11:11:16 README.md: Include link to project home page (for compliance with SignPath's Code of Conduct for Open Source projects)
DRC 6c2bc901 2022-11-03T14:39:19 Don't allow disabling in-memory src/dest managers By default, libjpeg-turbo 1.3.x and later have enabled the in-memory source/destination manager functions from libjpeg v8 when emulating the libjpeg v6b or v7 API/ABI, which has allowed operating system distributors to provide those functions without adopting the backward-incompatible libjpeg v8 API/ABI. Prior to libjpeg-turbo 1.5.x, it made sense to allow users to disable the in-memory source/destination manager functions at build time and thus retain both backward and forward API/ABI compatibility relative to libjpeg v6b or v7. Since then, however, we have introduced several new libjpeg API functions that break forward API/ABI compatibility, so it no longer makes sense to allow the in-memory source/destination managers to be disabled. libjpeg-turbo only claims to be backward-API/ABI-compatible, i.e. to allow applications built against libjpeg or an older version of libjpeg-turbo to work properly with the current version of libjpeg-turbo.
Jonathan Wright 240ba417 2020-01-07T16:40:32 Neon: Intrinsics impl. of prog. Huffman encoding The previous AArch64 GAS implementation has been removed, since the intrinsics implementation provides the same or better performance. There was no previous AArch32 GAS implementation.
DRC 7c1a1789 2020-11-05T16:04:55 Merge branch 'master' into dev
DRC 6e632af9 2020-11-04T10:13:06 Demote "fast" [I]DCT algorithms to legacy status - Refer to the "slow" [I]DCT algorithms as "accurate" instead, since they are not slow under libjpeg-turbo. - Adjust documentation claims to reflect the fact that the "slow" and "fast" algorithms produce about the same performance on AVX2-equipped CPUs (because of the dual-lane nature of AVX2, it was not possible to accelerate the "fast" algorithm beyond what was achievable with SSE2.) Also adjust the claims to reflect the fact that the "fast" algorithm tends to be ~5-15% faster than the "slow" algorithm on non-AVX2-equipped CPUs, regardless of the use of the libjpeg-turbo SIMD extensions. - Indicate the legacy status of the "fast" and float algorithms in the documentation and cjpeg/djpeg usage info. - Remove obsolete paragraph in the djpeg man page that suggested that the float algorithm could be faster than the "fast" algorithm on some CPUs.
DRC 59352195 2020-10-19T21:17:46 Merge branch 'master' into dev
DRC 1ed312ea 2020-10-15T17:47:31 "ARM"="Arm", "NEON"="Neon" Refer to: https://www.arm.com/company/policies/trademarks/arm-trademark-list/arm-trademark https://www.arm.com/company/policies/trademarks/arm-trademark-list/neon-trademark NOTE: These changes are only applied to change log entries for 2.0.x and later, since the change log is a historical record and Arm's new trademark policy did not go into effect until late 2017.
DRC fe79f56b 2020-07-28T15:09:00 Merge branch 'master' into dev
DRC 30282a87 2020-07-28T13:00:39 README.md, jquant2.c: Use gender-neutral pronouns Closes #444
DRC c4675d62 2019-12-31T00:42:53 Merge branch 'master' into dev
DRC 29f718ee 2019-12-31T00:06:11 README.md, package specs: Various tweaks - Don't enumerate the types of SIMD instructions that libjpeg-turbo supports, as this can change without notice. - Use more clear terminology when describing support for libjpeg v7/v8 features ("libjpeg" is, colloquially but not officially, the name for the IJG's software, whereas the "libjpeg API" refers to our emulation of said software.) - "PhotoShop" = "Photoshop" (StudLy Caps Police) - Adjust dynamic library versions to reflect the addition of jpeg_read_icc_profile() and jpeg_write_icc_profile() in libjpeg-turbo 2.0.x.
DRC 5db6a681 2019-08-30T12:02:50 README.md: Document memory debugger pitfalls (more specifically, the need to disable libjpeg-turbo's SIMD extensions when testing with valgrind, MSan, etc.) Addresses a concern expressed in #365
DRC f448279b 2019-08-30T11:15:47 README.md: Remove vestigial autotools references
DRC 450306a8 2018-04-06T18:31:17 READMEs: Mention that prog JPEG is now accelerated
DRC d83c9977 2018-03-23T00:00:58 README.md: clarify where API docs can be found
DRC 985ef4f9 2018-02-14T14:50:04 Merge branch 'master' into dev
Ben Boeckel 700de8aa 2018-02-14T15:41:36 README.md: Fix permissions
DRC 8c40ac8a 2017-11-16T18:46:01 Add TurboJPEG C example and clean up Java example Also rename example.c --> example.txt and add a disclaimer to that file so people will stop trying to compile it.
DRC 0ff7da71 2016-11-16T15:55:12 Advertise the new AVX2 SIMD extensions (our story so far ...)
DRC ab664e35 2016-11-18T09:09:41 BUILDING.md/README.md: Increment libjpeg SO age Documentation buglet. This should have been changed in 6ed4d9d11085acd04dc7f2f899848693976dc010 to reflect the addition of libjpeg API functions in libjpeg-turbo 1.5.
DRC ce26e83f 2016-11-18T09:08:52 README.md: Don't use trailing spaces as line break Makes it easier to maintain this file using editors that automatically remove trailing spaces.
Roberto Civille Rodrigues 9407cf7f 2016-09-22T00:42:25 README.md: Fix typo Introduced in 17de51835735e319ada5ca139a64227423946a8a Closes #102
DRC e5f280c4 2016-03-11T11:14:28 README.md: Link to BUILDING.md Addresses a concern expressed in #56 and #58.
DRC 4f581231 2016-03-09T17:23:45 BUILDING.md and README.md: Cosmetic tweaks
DRC fe11699d 2016-02-03T14:02:13 Adjust performance claims Document the latest benchmarks on the Nexus 5X and change the "2-4x" overall claim to "2-6x". The peak performance on x86 platforms was already closer to 5x, and the addition of SIMD-accelerated Huffman encoding gave it that extra push over the cliff.
DRC e42032ba 2015-10-10T10:56:58 README.md: create link for jcstest.c
DRC 17de5183 2015-10-10T10:34:55 Markdown versions of README, LICENSE, BUILDING
DRC 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.