FFmpeg audio API
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Discussion page regarding the rework of the ffmpeg audio api to acomodate the requirements needed for todays audio codecs.
Features needed
- Generalized downmixing (simd optimized)
Users should be able to set their own downmix coeffs.
- Codec setable downmixing coeffs:
The codec should be able to set and update the coefs during runtime(dca supports that feature, maybe ac3 also).
- Output channel request function (ie, request a specified number of channels, default should be >2 channels mapped to 2 channels).
- Channel reordering, currently there are diffrent orders depending on the codec.
- Simd optimized interleaving
- Allow planer output, (don't duplicate interleaving code in every codec)
- Add support for other bitdepths then 16bits (ie 24/8/32/float)
- Ability to access one channel from a multichannel stream
Whished for features
- Add a better fft routine, maybe the KISS one
- Fixedpoint mdct/fft functions
- Custom Audio filter support, could be based on the video filter api ideas
Current ideas
Thread with previous discussions in the subject. The thread has several ideas already implemented.
http://thread.gmane.org/gmane.comp.video.ffmpeg.devel/47485/focus=48097