On Sep 20, 2013, at 1:19 PM, Jean-Marc Valin <jmvalin at jmvalin.ca> wrote:>> I wasn't sure what bit rate was appropriate for "Very high quality" >> with opus, i.e. something that was "commonly indistinguishable from a >> WAV file". Any advice on that is appreciated. > > I would tend to recommend using around the same bitrate for Opus as > you'd be using for Vorbis.Good suggestion, but it seems to me that the measurement systems between the different encoders are different. With oggenc, we're using a "-q 6" Whereas for opusenc we're using "--bitrate 128" It's not a serious problem, I can "just use my ears" to decide when the quality seems good enough. -john
On 09/25/2013 03:57 PM, John Buckman wrote:> With oggenc, we're using a "-q 6" > > Whereas for opusenc we're using "--bitrate 128"oggenc -q 6 is calibrated to give an average of 192 kb/s on a large collection. So I suggest using --bitrate 192 for Opus if you want similar quality. To give you an idea, I don't remember hearing any artefacts at 128 kb/s VBR with 1.1, but some people have more sensitive ears than mind, so 192 sounds reasonable as a high-quality target. Cheers, Jean-Marc
On 09/25/2013 04:23 PM, Jean-Marc Valin wrote:> On 09/25/2013 03:57 PM, John Buckman wrote: >> With oggenc, we're using a "-q 6" >> >> Whereas for opusenc we're using "--bitrate 128" > > oggenc -q 6 is calibrated to give an average of 192 kb/s on a large > collection. So I suggest using --bitrate 192 for Opus if you want > similar quality. To give you an idea, I don't remember hearing any > artefacts at 128 kb/s VBR with 1.1, but some people have more sensitive > ears than mind, so 192 sounds reasonable as a high-quality target. > > Cheers, > > Jean-MarcIsn't the fact that Opus reaches similar quality levels at lower bitrates relevant to the choice, rather than matching bitrates with older codecs (i.e., Vorbis)? -- Libre Video http://librevideo.org