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Last modified: 10/3/2015

AltiVec/SSE Optimized LAME Encoder

This page provides Intel/PowerPC optimized version (using SSE/AltiVec) of LAME MP3 encoder.

What is it?

LAME is a free, open-sourced mp3 encoder. It is said that LAME offers the best quality among all mp3 encoders.

This page provides LAME binaries and patches optimized for Intel and PowerPC G4/G5 processor. This version is faster than the original version by utilizing SSE or AltiVec(aka Velocity Engine, VMX) in those processors. Binaries are built on OSX 10.6.8 with gcc 4.2.1. The archive only contains the encoder frontend.

These binaries sometimes produce a bit different encoding result compared to the reference one. This is due to the difference of the internal precision of floating-point representation between the vector FPU and the scalar FPU, and/or because floating point operations aren't commutative. Basically this should not affect the perceived quality, but if you worry about it try to invert the output waveform and mix with the reference one using the waveform editor like Audacity.

Changes

Performance

This version is about 85-105%/80-95% faster than the reference on PowerPC G4/G5 when using 3.98b8 (graph).

For intel processors, the official version already includes some SSE/MMX optimizations. In addition to this, some extra optimizations are applied in the version 3.99 distributed here (see the graph below).

LAME 3.99.5 (updated on 2012/2/29)

LAME 3.98.4 (updated on 2010/3/23)


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