Convert FLAC 24 bit 96khz to FLAC 16 bit 48khz

ffmpeg -i input.flac -sample_fmt s16 -ar 48000 output.flac

Some consider the SoX resampler superior to the default swresample library. 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

via