Files
mozjpeg/release
Kornel ed667d4bfd Merge remote-tracking branch 'libjpeg-turbo/3.0.x' into mozjpeg
* libjpeg-turbo/3.0.x: (135 commits)
  Ensure methods called by global funcs are init'd
  Build: Generate 32-bit supplementary ppc64 .deb
  Build: Fix float test errors with Xcode 14.2/Arm
  AltiVec: Disable/Fix some strict compiler warnings
  Neon: Disable some strict compiler warnings
  Build: Make Mac packaging architecture-agnostic
  Exclude more code if !(C|D)_LOSSLESS_SUPPORTED
  Fix OSS-Fuzz decompress_yuv fuzzer MSan failure
  TJ doc: Density params require YCbCr or grayscale
  Allow disabling prog/opt/lossless if prev. enabled
  GitHub: Use macos-13 runner image w/ Xcode 14.2
  LICENSE.md: Update copyright year
  ChangeLog: Document accidental fix from 9983840e
  tj3Set(): Allow TJPARAM_LOSSLESSPT vals from 0..15
  Build: Support LLVM/Windows
  tj3Transform: Don't calc dst subsamp unless needed
  Fuzz: Calc. xformed buf size based on dst. subsamp
  TJ: Calc. xformed buf sizes based on dst. subsamp
  Minor TurboJPEG doc tweaks
  turbojpeg.c: Fix -Wsign-compare compiler warning
  ...
2025-01-03 09:57:35 +00:00
..
2020-10-15 10:22:51 -05:00
2020-10-15 10:22:51 -05:00
2020-12-08 21:25:47 -06:00

libjpeg-turbo is a JPEG image codec that uses SIMD instructions to accelerate baseline JPEG compression and decompression on x86, x86-64, Arm, PowerPC, and MIPS systems, as well as progressive JPEG compression on x86, x86-64, and Arm systems.  On such systems, libjpeg-turbo is generally 2-6x as fast as libjpeg, all else being equal.  On other types of systems, libjpeg-turbo can still outperform libjpeg by a significant amount, by virtue of its highly-optimized Huffman coding routines.  In many cases, the performance of libjpeg-turbo rivals that of proprietary high-speed JPEG codecs.

libjpeg-turbo implements both the traditional libjpeg API as well as the less powerful but more straightforward TurboJPEG API.  libjpeg-turbo also features colorspace extensions that allow it to compress from/decompress to 32-bit and big-endian pixel buffers (RGBX, XBGR, etc.), as well as a full-featured Java interface.

libjpeg-turbo was originally based on libjpeg/SIMD, an MMX-accelerated derivative of libjpeg v6b developed by Miyasaka Masaru.  The TigerVNC and VirtualGL projects made numerous enhancements to the codec in 2009, and in early 2010, libjpeg-turbo spun off into an independent project, with the goal of making high-speed JPEG compression/decompression technology available to a broader range of users and developers.  libjpeg-turbo is an ISO/IEC and ITU-T reference implementation of the JPEG standard.