[opus] Questions about OPUS 1.2

[Jean-Marc Valin]

On 14/07/17 02:01 AM, José Hernan Yanes wrote:
> I would like to ask them Why do they always say that OPUS is a leader in
> 64k and 96k, but that it is not 128k or 192k? Does OPUS not achieve
> transparency in 128k and at 160k is it like a 320k MP3 file?

The problem is that the quality of Opus, AAC and Vorbis is so close to
transparent at 128 kbps that it's nearly impossible to conduct testing
and get statistically significant results. Sure, a handful of people can
hear a difference on a handful of samples, but to get anything reliable
you'd need a very large number of listeners *and* a very large number of
samples. Even 96 kb/s was really hard to test. So for 128 kb/s and
above, you might as well assume that all codecs are about as good except
for MP3 that's still worse.

Cheers,

	Jean-Marc