Speex dev - Aug 2011 - Correct detection of bitrate

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I have read the speex manual, looked at the example code, but for some reason
the first encoded byte does not have the wideband bit set and the mode bits are
also wrong even though I am encoding in wideband mode.

I am sure that I am doing something wrong, but I can't figure out what it
is.

I have included my code below....

I would expect that the MSB of the first encoded byte is 1 (wideband) and that
the next 4 bits would be 8 (because I requested mode 8)...but this is the
mapping I see

here is my code
?
?
Init Encoder:
speex_bits_init(&thisEncoder->bits);
thisEncoder->speexEncoderInstance =
speex_encoder_init(speex_lib_get_mode(SPEEX_MODEID_WB));
speex_encoder_ctl(thisEncoder->speexEncoderInstance, SPEEX_SET_QUALITY,
&encodermode);
?
where encodermode = 8
?
?
Init Decoder:
thisDecoder->speexDecoderInstance =
speex_decoder_init(speex_lib_get_mode(SPEEX_MODEID_WB));
speex_decoder_ctl(thisDecoder->speexDecoderInstance, SPEEX_SET_QUALITY,
&decodermode);
speex_bits_init(&thisDecoder->bits);
?
where decodermode = 8
?
?
Encode:
/* Reset bitstream */
speex_bits_reset(&thisEncoder->bits);
/* PCM -> Bitstream */
speex_encode_int(thisEncoder->speexEncoderInstance, pAudiodataIn,
&thisEncoder->bits);
/* Bitstream -> Byteblock */
nBytes = speex_bits_nbytes(&thisEncoder->bits);
nBytes = speex_bits_write(&thisEncoder->bits, (i8*) pEncodedAudioOut,
nBytes);
firstbyte = (pEncodedAudioOut[0] >> 3) & 15;
printf("Actual mode: %d \n", firstbyte);
wideband = (pEncodedAudioOut[0] >> 7);
printf("Wideband: %d \n", wideband);
?
?
Decode:
/* Byteblock -> Bitstream */
speex_bits_read_from(&thisDecoder->bits, (i8*) pEncodedAudioIn, (int)
thisDecoder->payloadSize);
/* Bitstream -> PCM */
speex_decode_int(thisDecoder->speexDecoderInstance,
&thisDecoder->bits, pDecodedAudioOut);
speex_bits_reset(&thisDecoder->bits);
?

?
?
What am I doing wrong??
?
Thanks.
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Hi,
?
Is there anybody out there who can tell me how to solve the following problem:
?
An RTP payload of encoded speex data is received. The length of the payload is
N bytes. The length corresponds to 20ms * K of encoded audio where K is an
unknown integer. The audio was encoded by an encoder in wideband mode.
?
How do I partition the payload when I don't know which bitrate mode of the
encoder? I want to hand over 20ms of encoded audio to the decoder, but to be
able to do that I need to know how many bytes of the payload corresponds to
20ms.
?
I read that the bitrate mode and the wideband bit is embedded in the first byte,
but
that is not what I actually see. What I see is that the MSB of the first encoded
byte
is 0 and the following bits do not correspond to the bitrate mode that was used
when
encoding the audio.
?
So I am wondering what I am doing wrong.
?
Is it because the first part of the payload is a narrowband bitstream ? And I
need to
extract the narrowband bitrate mode first,?figure out how many bytes (M) that
mode
corresponds to?and skip?M?bytes ahead to get the wideband
bitrate mode? 
?
Or is there a quicker way of doing it?
?
Can somebody please shed some light on this??
?
Thank you!!
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