[FFmpeg-user] Opus : difference between .opus and .ogg file extension

[Carl Eugen Hoyos]

2017-11-30 11:24 GMT+01:00  <nerbrume at free.fr>:

> I'm encoding my audio files to opus, with the following command:
>> ffmpeg -i test.mp3 -acodec libopus -b:a 64000 -vbr on test.opus
> (Debian squeeze, ffmpeg version 3.3.5)
>
> According to wikipedia, the "opus" container should just be an ogg
> container (https://en.wikipedia.org/wiki/Opus_%28audio_format%29).
> However, encoding my file with an ogg extension :
>> ffmpeg -i test.mp3 -acodec libopus -b:a 64000 -vbr on test.ogg
> produces a different file from the previous one (md5 are mismatched).

Use -fflags +bitexact to get identical files, you will also get different
files when writing to out1.ogg and out2.ogg.

The file suffix ".opus" is just a shorthander for "-acodec opus -f ogg".

Carl Eugen