2009/2/26 Dave Chapman <d...@dchapman.com>: > Cristian Adam wrote: >> On Wed, Feb 25, 2009 at 2:23 PM, Brian Willoughby >> <bri...@sounds.wa.com>wrote: >> >>> A better suggestion might be to start with libFLAC, optimize as >>> needed, and then submit the optimizations back to the FLAC project >>> where they will be more widely useful. >>> >>> But that's just my opinion. >>> >> >> I agree. This way the DirectShow filter for Windows Mobile (based on >> libFLAC) will >> also benefit from those optimizations. > > When Rockbox switched from libFLAC to the ffmpeg decoder, FLAC turned > from one of our slowest codecs, to the fastest. The difference was > extremely dramatic. > > libFLAC is the _reference_ implementation of FLAC, not one that is > designed to be the ideal decoder everywhere. That's the advantage of > open codecs - the specification is public, and third-party > encoders/decoders should be encouraged, not immediately rejected without > consideration. > > I'm not talking about things that can be achieved by optimising libFLAC. > One of the reasons the Rockbox version of the ffmpeg decoder is so > fast on our target devices is because it is very tightly integrated (no > abstract layers of API). i.e. we created a FLAC codec designed > specifically for the Rockbox codec API. > > This involved extracting the FLAC decoder from ffmpeg, using the core > decoding parts of that code, and writing new code just for Rockbox. > Whilst this was a lot more work to do than simply linking libFLAC, the > end result was very worthwhile.
That's fair enough: people should be able to make their own implementations. Ensuring compatability between different implementations is a lot of work and can be painful for everyone involved, but it has to be done. First step: does anyone have some example files that should work but perhaps don't work in FFmpeg/Rockbox, that could be added to their test suites? Conrad. _______________________________________________ Flac-dev mailing list Flac-dev@xiph.org http://lists.xiph.org/mailman/listinfo/flac-dev
