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Revision as of 16:13, 31 May 2010



Replace libjpeg by libjpeg-turbo

Summary

libjpeg-turbo is fork of the original libjpeg project. It contains numerous performance related enhancements and is at least twice faster in JPEG compression/decompression than original libjpeg on platforms with MMX/SSE instruction set. It has same API/ABI like original libjpeg and also runs on non-SSE platforms where is around 25% faster.

Owner

Current status

  • Targeted release: Fedora 14
  • Last updated: 2010-05-31
  • Percentage of completion: 0%

Detailed Description

Everything is written in summary.

Benefit to Fedora

Much faster JPEG compression/decompression library. JPEG codec is widely used and it is good to speed up core library which implements it. Additionally, libjpeg-turbo is developed in more open-source manner than original libjpeg.

Scope

All packages which depends on libjpeg have to be rebuilt against libjpeg-turbo. There are no API/ABI changes so temporary symlink libjpeg->libjpeg-turbo will be provided to make this task easier.

How To Test

You can use any program which uses libjpeg-turbo code. You should try to perform JPEG compression/decompression to and check if you don't see artefacts. You can also compare speed of the libjpeg-turbo against libjpeg, you should be able to visually check that libjpeg-turbo is really faster.

User Experience

A lot faster JPEG compression/decompression

Dependencies

462 packages (repoquery --alldeps --whatrequires libjpeg |wc -l)

Contingency Plan

Use libjpeg when libjpeg-turbo hits some serious problems. Both libraries can coexist.

Documentation

http://sourceforge.net/projects/libjpeg-turbo

Release Notes

libjpeg library has been replaced by libjpeg-turbo library which has same API/ABI but is at least twice faster on all primary architectures and about 25% faster on secondary architectures

Comments and Discussion