speex_encoder_ctl always returning 0 (DTX), adding Speex DTX support to Asterisk Options

[JimmyJames]

I'm currently playing with the Asterisk source code getting it to support Speex DTX mode. There are a few bugs left to sort out but one of the problems I've got is determining if a given frame in DTX is silent and need not be transmitted.

The libspeex API reference guide says that a call (any call?) to speex_encoder_ctl should return 0 in the case of silence (and 1 otherwise) but every time I call it I get a return value of 0, regardless of whether there's silence or not.

I'm currently trying to doing a:

CODE

int dtx_transmit = speex_encoder_ctl(tmp->speex, SPEEX_GET_FRAME_SIZE, &tmp->framesize);

After every call to:

CODE

speex_encode(tmp->speex, fbuf, &tmp->bits);

Has anyone been able to determine silence status using speex_encoder_ctl? Please let me know if I'm using it incorrectly.

Thanks,

James

[JimmyJames]

Hold the phone...

It seems that speex_encode returns the dtx-silence flag, as would make sense, rather than speex_encoder_ctl as claimed in the documentation.

The lesson here? Never trust an API

[jmvalin]

Hold the phone...

It seems that speex_encode returns the dtx-silence flag, as would make sense, rather than speex_encoder_ctl as claimed in the documentation.

The lesson here?  Never trust an API

Sorry about that. I fixed it in SVN. Any other stpuid thing in the API doc?

[JimmyJames]

Sorry about that. I fixed it in SVN. Any other stpuid thing in the API doc?

No worries Jean-Marc.

The only other problem I noticed in the codec manual is in section 4.5

That terminator consists of the code 15 (decimal), encoded with 5 bits, as shown in figure 4.

with no figure 4 shown. Not that we need a figure anyway.

Thanks for all your work putting Speex together - great piece of software!

[jmvalin]

The only other problem I noticed in the codec manual is in section 4.5

That terminator consists of the code 15 (decimal), encoded with 5 bits, as shown in figure 4.

with no figure 4 shown. Not that we need a figure anyway.

Thanks for all your work putting Speex together - great piece of software!

Oops... I meant *Table* 4.