[Speex-dev] Determine number of 20ms frames in packet - without decoding

Alexander Chemeris Alexander.Chemeris at sipez.com
Wed Feb 20 02:19:06 PST 2008


On 2/20/08, Jean-Marc Valin <jean-marc.valin at usherbrooke.ca> wrote:
> Alexander Chemeris wrote:
> > On 2/16/08, Jean-Marc Valin <jean-marc.valin at usherbrooke.ca> wrote:
> >>> Oh, you're right, inband handling is different, but it's a matter of one
> >>> flag, passed to functioin. Probably not that much to keep code DRY.
> >> Well, let's first merge your code and then we'll see about possible
> >> simplifications.
> >
> > Waiting for your decision ;)
> > I guess you stopped on the fact you need to check my statement
> > about wb_skip_table?
>
> Oh, your table looked fine. I think it's mine that was wrong for the
> "null mode" (which nobody ever uses I guess!).

I'm not sure, but I guess it may be used in VBR or DTX mode?
At least that's why I kept it.

So, what's the next step towards intergartion? I guess it should
be somehow made available from Speex API level, e.g. with
new speex_decoder_ctl() or speex_lib_ctl() request? I have
no idea about the best way here, and would appreciate your
advices.

> > It would be good to define - it is very misleading for newcomers
> > as it is now. And I would like to say, that from user point of view
> > "frame" meaning all "layers" is natural, because most of users
> > are not aware of any "layers" - they want to operate with encoded
> > packet as a whole and do not think of internals. Actually, I've got
> > some idea about "layers" only when was forced to write sample
> > number calculation code.
>
> Well, turns out I use frame size for both meanings -- which normally
> isn't a problem because few people are directly aware of the "layers" in
> the first place.

Exactly.

> > Sure. But in SDP you specify mode and not bitrate. ;) So I want
> > to operate with the same things as in SDP.
>
> I see. BTW, you can ask the full bit-rate to the encoder or decoder.
> It's only the mode that give you the layer's bit-rate (which we might
> want to change).

Sorry, not sure I follow you. What do you mean by "you can ask the full
bit-rate to the encoder or decoder"?


-- 
Regards,
Alexander Chemeris.

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