ffmpeg FLAC 24 bit 96khz to 16 bit 48khz
Trying to figure out ffmpeg, currently working on getting 24bit/96khz FLAC files into 16bit/48khz.
Answer
Basic example
ffmpeg -i input.flac -sample_fmt s16 -ar 48000 output.flac
- List sample formats:
ffmpeg -sample_fmts - List additional flac encoding options:
ffmpeg -h encoder=flac
aresample filter example
ffmpeg -i input.flac -af aresample=out_sample_fmt=s16:out_sample_rate=48000 output.flac
Either example will result in the same output: you can verify with the hash muxer.
Changing the dithering method
See the -dither_method option for a list of available dithering methods and additional resampling options. Example:
ffmpeg -i input.flac -dither_method triangular_hp -sample_fmt s16 -ar 48000 output.flac
SoX resampler
FFmpeg supports two resamplers: the default swresample library, and the external SoX resampler (soxr).
To use soxr your ffmpeg must be compiled with --enable-libsoxr. Then choose it with the -resampler option:
ffmpeg -i input.flac -resampler soxr -sample_fmt s16 -ar 48000 output.flac
Or use the aresample filter to do it all:
ffmpeg -i input.flac -af aresample=resampler=soxr:out_sample_fmt=s16:out_sample_rate=48000 output.flac