Hi list,
I'm trying to figure out how to do the most compatible implementation that
will
work with as many versions of Speex as possible. I am streaming multi frame
Speex blocks over a TCP connection which works fine as long as the version of
Speex is the same on both sides. When using a newer Speex (1.1.?) to encode
and an older version to decode (1.0.5), it does not work.
The encoder code look like this:
int AudioEncoderSpeex::writeSamples(const float *samples, int count)
{
for (int i=0; i<count; ++i)
{
sample_buf[buf_len++] = samples[i] * 32767.0;
if (buf_len == frame_size)
{
speex_encode(enc_state, sample_buf, &bits);
buf_len = 0;
if (++frame_cnt == 4) // Four frames per packet
{
speex_bits_insert_terminator(&bits);
int nbytes = speex_bits_nbytes(&bits);
char output_buf[nbytes];
nbytes = speex_bits_write(&bits, output_buf, nbytes);
writeEncodedSamples(output_buf, nbytes);
speex_bits_reset(&bits);
frame_cnt = 0;
}
}
}
return count;
} /* AudioEncoderSpeex::writeSamples */
The decoder have looked like this for quite a while:
void AudioDecoderSpeex::writeEncodedSamples(void *buf, int size)
{
char *ptr = (char *)buf;
speex_bits_read_from(&bits, ptr, size);
float samples[frame_size];
#if SPEEX_MAJOR > 1 || (SPEEX_MAJOR == 1 && SPEEX_MINOR >= 1)
while (speex_decode(dec_state, &bits, samples) == 0)
#else
while ((speex_decode(dec_state, &bits, samples) == 0) &&
(speex_bits_remaining(&bits) > 0))
#endif
{
for (int i=0; i<frame_size; ++i)
{
samples[i] = samples [i] / 32767.0;
}
sinkWriteSamples(samples, frame_size);
}
} /* AudioDecoderSpeex::writeEncodedSamples */
This have worked well when using the same version of Speex on both sides. When
using 1.1 on the encoder and 1.0 on the decoder, the number of frames decoded
varies between three and four even though four frames are always sent. The use
of speex_bits_remaining is one I have found by Googling. I started to wonder
if it's wrong now though. If I change the comparison to read
"speex_bits_remaining(&bits) >= 0" I always get four frames
decoded. However,
it still does not sound correctly. The change from ">" to
">=" makes sense
though. It should be OK for speex_decode to consume all bits so zero bits
remaining should be OK (or?).
The original question was if versions 1.0 and >= 1.1 is compatible. Can I
make
the code work in all cases or am I on a "mission impossible"?
Regards,
Tobias
All version after 1.0 are compatible with each other and with 1.0. Jean-Marc On 2010-04-10 15:44, Tobias wrote:> Hi list, > > I'm trying to figure out how to do the most compatible implementation that will > work with as many versions of Speex as possible. I am streaming multi frame > Speex blocks over a TCP connection which works fine as long as the version of > Speex is the same on both sides. When using a newer Speex (1.1.?) to encode > and an older version to decode (1.0.5), it does not work. > > The encoder code look like this: > > int AudioEncoderSpeex::writeSamples(const float *samples, int count) > { > for (int i=0; i<count; ++i) > { > sample_buf[buf_len++] = samples[i] * 32767.0; > > if (buf_len == frame_size) > { > speex_encode(enc_state, sample_buf,&bits); > buf_len = 0; > > if (++frame_cnt == 4) // Four frames per packet > { > speex_bits_insert_terminator(&bits); > int nbytes = speex_bits_nbytes(&bits); > char output_buf[nbytes]; > nbytes = speex_bits_write(&bits, output_buf, nbytes); > writeEncodedSamples(output_buf, nbytes); > speex_bits_reset(&bits); > frame_cnt = 0; > } > } > } > > return count; > > } /* AudioEncoderSpeex::writeSamples */ > > > > The decoder have looked like this for quite a while: > > void AudioDecoderSpeex::writeEncodedSamples(void *buf, int size) > { > char *ptr = (char *)buf; > > speex_bits_read_from(&bits, ptr, size); > float samples[frame_size]; > #if SPEEX_MAJOR> 1 || (SPEEX_MAJOR == 1&& SPEEX_MINOR>= 1) > while (speex_decode(dec_state,&bits, samples) == 0) > #else > while ((speex_decode(dec_state,&bits, samples) == 0)&& > (speex_bits_remaining(&bits)> 0)) > #endif > { > for (int i=0; i<frame_size; ++i) > { > samples[i] = samples [i] / 32767.0; > } > sinkWriteSamples(samples, frame_size); > } > } /* AudioDecoderSpeex::writeEncodedSamples */ > > > This have worked well when using the same version of Speex on both sides. When > using 1.1 on the encoder and 1.0 on the decoder, the number of frames decoded > varies between three and four even though four frames are always sent. The use > of speex_bits_remaining is one I have found by Googling. I started to wonder > if it's wrong now though. If I change the comparison to read > "speex_bits_remaining(&bits)>= 0" I always get four frames decoded. However, > it still does not sound correctly. The change from ">" to">=" makes sense > though. It should be OK for speex_decode to consume all bits so zero bits > remaining should be OK (or?). > > The original question was if versions 1.0 and>= 1.1 is compatible. Can I make > the code work in all cases or am I on a "mission impossible"? > > Regards, > Tobias > _______________________________________________ > Speex-dev mailing list > Speex-dev at xiph.org > http://lists.xiph.org/mailman/listinfo/speex-dev > >
On Saturday 10 April 2010 21.51.55 Jean-Marc Valin wrote:> All version after 1.0 are compatible with each other and with 1.0.Hi Jean-Marc and thanks for the quick reply. I have now looked at this further and got the idea to hard code the number of frames in the decoder temporarily as a test and voil?, it works! The problem seem to be some incompatibility in the termination handling. After processing exactly four frames the number of remaining bits can be anything from zero to seven which I guess is normal. However, if I use the while loop below, speex_decode will get called one more time (a total of five times) and that seem to mess up the decoder state. The decoded audio get sort of "bubbly". while ((speex_decode(dec_state,&bits, samples) == 0) && (speex_bits_remaining(&bits) >= 0)) {} As far as I can see, the termination handling is not compatible when encoding with, in this case, Speex ver 1.2rc1 and decoding with ver 1.0.5. Do you agree or have I done something wrong in my code? The full code can be found here: http://svxlink.svn.sf.net/viewvc/svxlink/trunk/src/async/audio/AsyncAudioDecoderSpeex.cpp?view=markup http://svxlink.svn.sf.net/viewvc/svxlink/trunk/src/async/audio/AsyncAudioEncoderSpeex.cpp?view=markup I guess I could solve this problem by transmitting the frame count out-of-band but if Speex can handle it, it's better. Regards, Tobias> > Jean-Marc > > On 2010-04-10 15:44, Tobias wrote: > > Hi list, > > > > I'm trying to figure out how to do the most compatible implementation > > that will work with as many versions of Speex as possible. I am > > streaming multi frame Speex blocks over a TCP connection which works > > fine as long as the version of Speex is the same on both sides. When > > using a newer Speex (1.1.?) to encode and an older version to decode > > (1.0.5), it does not work. > > > > The encoder code look like this: > > > > int AudioEncoderSpeex::writeSamples(const float *samples, int count) > > { > > > > for (int i=0; i<count; ++i) > > { > > > > sample_buf[buf_len++] = samples[i] * 32767.0; > > > > if (buf_len == frame_size) > > { > > > > speex_encode(enc_state, sample_buf,&bits); > > buf_len = 0; > > > > if (++frame_cnt == 4) // Four frames per packet > > { > > > > speex_bits_insert_terminator(&bits); > > int nbytes = speex_bits_nbytes(&bits); > > char output_buf[nbytes]; > > nbytes = speex_bits_write(&bits, output_buf, nbytes); > > writeEncodedSamples(output_buf, nbytes); > > speex_bits_reset(&bits); > > frame_cnt = 0; > > > > } > > > > } > > > > } > > > > return count; > > > > } /* AudioEncoderSpeex::writeSamples */ > > > > > > > > The decoder have looked like this for quite a while: > > > > void AudioDecoderSpeex::writeEncodedSamples(void *buf, int size) > > { > > > > char *ptr = (char *)buf; > > > > speex_bits_read_from(&bits, ptr, size); > > float samples[frame_size]; > > > > #if SPEEX_MAJOR> 1 || (SPEEX_MAJOR == 1&& SPEEX_MINOR>= 1) > > > > while (speex_decode(dec_state,&bits, samples) == 0) > > > > #else > > > > while ((speex_decode(dec_state,&bits, samples) == 0)&& > > > > (speex_bits_remaining(&bits)> 0)) > > > > #endif > > > > { > > > > for (int i=0; i<frame_size; ++i) > > { > > > > samples[i] = samples [i] / 32767.0; > > > > } > > sinkWriteSamples(samples, frame_size); > > > > } > > > > } /* AudioDecoderSpeex::writeEncodedSamples */ > > > > > > This have worked well when using the same version of Speex on both sides. > > When using 1.1 on the encoder and 1.0 on the decoder, the number of > > frames decoded varies between three and four even though four frames are > > always sent. The use of speex_bits_remaining is one I have found by > > Googling. I started to wonder if it's wrong now though. If I change the > > comparison to read > > "speex_bits_remaining(&bits)>= 0" I always get four frames decoded. > > However, it still does not sound correctly. The change from ">" to">=" > > makes sense though. It should be OK for speex_decode to consume all bits > > so zero bits remaining should be OK (or?). > > > > The original question was if versions 1.0 and>= 1.1 is compatible. Can I > > make the code work in all cases or am I on a "mission impossible"? > > > > Regards, > > Tobias