[Vorbis] Re: bitrate limits don't work with -q settings?

[Nic Watson]

I'm glad I'm not the only one running into this problem.  I'm pretty 
sure the -m setting is ignored when the -q option is used.  I just tried it:

oggenc -q 3 -m 96000 sinewave.flac -> Average bitrate: 69.1 kb/s

Empirically, I've noticed that the iRiver player will not play a song 
(it says OGG FORMAT NOT SUPPORTED or somesuch) if its abr < 96kbps.  It 
will also pop or end the song abruptly if the song at any time goes 
below 96kbps.

Nic

Frank Murphy wrote:

>>Here are some more tests i did with various combinations.
>>
>>oggenc -q 3 sinewave.flac -> Average bitrate: 69.1 kb/s
>>oggenc -m 96 sinewave.flac -> Average bitrate: 96.9 kb/s
>>oggenc -m 96 -q3 sinewave.flac -> Average bitrate: 69.1 kb/s
>>oggenc -q 3 -m 360 sinewave.flac -> Average bitrate: 69.1 kb/s
>>oggenc -m 96 -M 360 sinewave.flac ->  Average bitrate: 130.6 kb/s
>>oggenc -q 3 -m 96 -M 360 sinewave.flac -> Average bitrate: 0.7 kb/s
>>oggenc -q 3 -m 360 -M 360 sinewave.flac -> Average bitrate: 0.7 kb/s
>>
>>The last ones are really weird? The file ony has one tick at the
>>beginning an after that silence.
>>
>>The issue however is when using a -q3 together with a -m 96 oggenc
>>kind of ignores the -m 96. Is this normal?
> 
> 
> So I also got an iRiver iFP machine because of it's ogg support. I've recently 
> discovered its problems with oggs encoded at less than 96kbps (though I'm not 
> sure which thing needs to be 96kbps). I saw your posting and I think I've 
> discovered the oggenc bug that you're seeing. It seems that when -m and -q 
> are used together, the -m takes the number to be bps instead of kbps (or kb/s 
> depending on where you look in ogginfo). So in order to get the behavior you 
> want, you need to encode with -q 3 and -m 96000. This is all experimental for 
> me too, but I think the 96000 isn't enough. I'll be messing with values a 
> little higher to avoid any pops.
> 
> I haven't seen any official iRiver statement about which bitrates are 
> supported, but I've seen hearsay that it accepts only between 96kpbs and 
> 220bps. But I don't know if that's Average bitrate, nominal bitrate, or what. 
> On the website, it talks about how many hours of music can be fit with 64kbps 
> ogg files, but that doesn't reflect reality.
> 
> Frank
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