Speex dev - Aug 2004 - About reducing noise..

Hi,

It's hard to say what the problem is. Common problems are sample
encoding mismatch (16-bit vs. float vs. ulaw, ...) or problems handling
the bits. One other thing is the sampling rate. Speex is optimized for
8, 16 and 32 kHz. Also, are you feeding it a mono stream?

        Jean-Marc

Le mar 24/02/2004  00:42, Ali Naqi a crit :
> Hello, 
> 
>  
> 
> When I decode a recoded sound encoded by speex, it has too much noise.
> The noise is slightly reduced if I set the quality to 10. How do I
> get rid of this noise? The code is as follows
> 
>  
> 
>  
> 
> For encoding 
> 
>  
> 
> state = speex_encoder_init ( &speex_nb_mode );
> 
>  
> 
> tmp = 7;
> 
> speex_encoder_ctl ( state, SPEEX_SET_MODE, &tmp);
> 
>  
> 
> // set quality
> 
> tmp = 10;
> 
> speex_encoder_ctl ( state, SPEEX_SET_QUALITY, &tmp);
> 
>  
> 
> // initialize bits
> 
> speex_bits_init(&bits);
> 
>  
> 
>  
> 
> while( 1 )
> 
> {
> 
>       // read FRAME_SIZE bytes from buffer
> 
>       // convert to short
> 
>       for ( int i = 0; i < FRAME_SIZE; i++)
> 
>             in[i] = out_buffer[i];
> 
>  
> 
>       speex_bits_reset(&bits);
> 
>  
> 
>       // encode
> 
>       speex_encode ( state, in, &bits);
> 
>  
> 
>       // copy bits to an array of chars 
> 
>       nbBytes = speex_bits_write ( &bits, cbits, 200);
> 
>  
> 
>       // copy these cbits into a buffer
> 
>       CopyBuffer(pBuffer + dwLength, cbits, nbBytes);
> 
>       dwLength += nbBytes;
> 
> }
> 
>  
> 
> // uninitialize
> 
>  
> 
> For decoding 
> 
>  
> 
> SpeexBits bits;
> 
> int i, tmp;
> 
>  
> 
> state = speex_decoder_init(&speex_nb_mode);
> 
> tmp =1;
> 
> speex_decoder_ctl(state, SPEEX_SET_ENH, &tmp);
> 
>  
> 
> speex_bits_init(&bits);
> 
> char temp[10];
> 
> long sizeToRead = 4;
> 
> while(1)
> 
> {
> 
>       int ret = ReadFile(file,temp, sizeToRead , &bytesRead,NULL);
> 
>       if( bytesRead == 0 )
> 
> {
> 
>             break;
> 
>       }
> 
>       nbBytes = atoi(temp);
> 
>       totalBytesRead += bytesRead;
> 
>  
> 
>       ret = ReadFile(file, cbits, nbBytes, &bytesRead, NULL);
> 
>       totalBytesRead += bytesRead;
> 
>       speex_bits_read_from(&bits, cbits, nbBytes);
> 
>       speex_decode(state, &bits, out);
> 
>       for( i=0; i <FRAME_SIZE; i++)
> 
>             buf[i] = (char)out[i];
> 
>       // write to file
> 
> WriteFile(file2, buf, FRAME_SIZE, &bytesWritten, NULL);
> 
>       totalBytesWritten+= bytesWritten;
> 
> }
> 
>  
> 
> I am using wave api for capturing and playing back sound. 
> 
>  
> 
> Please guide me in this problem.
> 
>  
> 
> Regards,
> 
> Ali Naqi Shaheen, 
> 
>  
-- 
Jean-Marc Valin, M.Sc.A., ing. jr.
LABORIUS (http://www.gel.usherb.ca/laborius)
Universit de Sherbrooke, Qubec, Canada


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Hello, 
 
When I decode a recoded sound encoded by speex, it has too much noise.
The noise is "slightly" reduced if I set the quality to 10. How do I
get
rid of this noise? The code is as follows.
 
 
For encoding .
 
state = speex_encoder_init ( &speex_nb_mode );
 
tmp = 7;
speex_encoder_ctl ( state, SPEEX_SET_MODE, &tmp);
 
// set quality
tmp = 10;
speex_encoder_ctl ( state, SPEEX_SET_QUALITY, &tmp);
 
// initialize bits
speex_bits_init(&bits);
 
 
while( 1 )
{
      // read FRAME_SIZE bytes from buffer
      // convert to short
      for ( int i = 0; i < FRAME_SIZE; i++)
            in[i] = out_buffer[i];
 
      speex_bits_reset(&bits);
 
      // encode
      speex_encode ( state, in, &bits);
 
      // copy bits to an array of chars 
      nbBytes = speex_bits_write ( &bits, cbits, 200);
 
      // copy these cbits into a buffer
      CopyBuffer(pBuffer + dwLength, cbits, nbBytes);
      dwLength += nbBytes;
}
 
// uninitialize
 
For decoding .
 
SpeexBits bits;
int i, tmp;
 
state = speex_decoder_init(&speex_nb_mode);
tmp =1;
speex_decoder_ctl(state, SPEEX_SET_ENH, &tmp);
 
speex_bits_init(&bits);
char temp[10];
long sizeToRead = 4;
while(1)
{
      int ret = ReadFile(file,temp, sizeToRead , &bytesRead,NULL);
      if( bytesRead == 0 )
{
            break;
      }
      nbBytes = atoi(temp);
      totalBytesRead += bytesRead;
 
      ret = ReadFile(file, cbits, nbBytes, &bytesRead, NULL);
      totalBytesRead += bytesRead;
      speex_bits_read_from(&bits, cbits, nbBytes);
      speex_decode(state, &bits, out);
      for( i=0; i <FRAME_SIZE; i++)
            buf[i] = (char)out[i];
      // write to file
WriteFile(file2, buf, FRAME_SIZE, &bytesWritten, NULL);
      totalBytesWritten+= bytesWritten;
}
 
I am using wave api for capturing and playing back sound. 
 
Please guide me in this problem.
 
Regards,
Ali Naqi Shaheen, 
 

<p>--- >8 ----
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