Source: The wonderful ffmprovisr
This will convert your WAV files to MP3s.
-i input_file - path and name of the input file
-write_id3v1 1 - This will write metadata to an ID3v1 tag at the head of the file, assuming you’ve embedded metadata into the WAV file.
-id3v2_version 3 - This will write metadata to an ID3v2.3 tag at the tail of the file, assuming you’ve embedded metadata into the WAV file.
-dither_method triangular - Dither makes sure you don’t unnecessarily truncate the dynamic range of your audio.
-out_sample_rate 48k - Sets the audio sampling frequency to 48 kHz. This can be omitted to use the same sampling frequency as the input.
-qscale:a 1 - This sets the encoder to use a constant quality with a variable bitrate of between 190-250kbit/s. If you would prefer to use a constant bitrate, this could be replaced with -b:a 320k to set to the maximum bitrate allowed by the MP3 format. For more detailed discussion on variable vs constant bitrates see here.
output.mp3 - path and name of the output file
A couple notes: About ID3v2.3 tag: ID3v2.3 is better supported than ID3v2.4, FFmpeg’s default ID3v2 setting.
About dither methods: FFmpeg comes with a variety of dither algorithms, outlined in the official docs, though some may lead to unintended, drastic digital clipping on some systems.
