ACELP | ADPCM | AMBE | AMR | AMR-NB | CELP | Codebook | DTMF | G.723 | G.726 | G.729 | GSM | Interpolation | LPC | LSF | LSP | MELP | PCM | Perceptual | Pitch | PSOL | QCELP | Quantization | SMV | VAD | Vocoder

Hi, I am working on a project that implements CELP coding, as in AMR codec for GSM. The
codec uses a 'codebook' to store 'code vectors', which are compared with excitation vectors and
the error minimised till a match is found. This match is used to synthesise speech.

The spec I am using, 3GPP TS 26.090 ver 6.0.0, r6, specifies codebook architecture but not how
it is created.

So how is this codebook to be generated ?

I have been looking on the net and have found nothing specific. Previously I wrote a c++
code for LZW compression. It had a constantly updated dictionary implemented using a hash
table, with entries from the text stream. Should I do something similar by recording audio
samples ? If so, how are they to be converted into code vectors ?

Any help/advice will be appreciated. Thanks in advance.

-Abhijit Krishna
	

(You need to be a member of speechcoding -- send a blank email to speechcoding-subscribe@yahoogroups.com )