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Need source code of QCELP

Started by Unknown October 12, 1999

Hi all,

I am intend to learn much about variable rate speech coding, and I take
QCELP (Qualcomm CELP) to study.I am looking for any good reference that
have complete describe about the concept and algorithm of this
vocoder.

Especially I need the source code. If you have or know the information
where I can find it on the web, please let me know.
(I have trying to search it on the Internet, but no result). Thanks alot.

Mohamad Alifikri

--------------------------------




Hi all,

if anyone interested in the source code of the QCELP coder, go
to:

ftp://ftp.qualcomm.com/pub/vocoder/IS96a/

Check the web site of Qualcomm (www.qualcomm.com) to find
more info about the latest wave of VBR vocoders.

For an excellent overview of VBR speech coding check:

A. Das, E. Paksoy, and A. Gersho," Multimode and Variable-Rate Coding of
Speech", Chapter 7, Speech Coding and Syntehsis Book, Eds. W.B. Kleijn and
K.K. Pliawal, 1995, Elsiver Science.

There you can find lists of major work in developing VBR coders including
QCELP.

However, check the ICASPP 97 and other latest ICASSP conferences
(ICASSP 99 for example) for some new good work in VBR speech coding.

Currently, the TIA association is developing a new set of VBR speech
coders for CDMA under the name "Selectable Mode Vocoder (SMV)".

Do not forget to read about the CDMA Enhanced Variable Rate Vocoder
(EVRC), and the Q13 CDMA vocoder.

Good luck.

----------------------------
Khaled El-Maleh
Department of Electrical & Computer Engineering
McGill University
3480 University St.
Montreal Quebec
H3A 2A7 Canada

Telephone: (514) 398-5233 (O)
Fax : (514) 398-4470
On Wed, 13 Oct 1999 wrote:

>
> Hi all,
>
> I am intend to learn much about variable rate speech coding, and I take
> QCELP (Qualcomm CELP) to study.I am looking for any good reference that
> have complete describe about the concept and algorithm of this
> vocoder.
>
> Especially I need the source code. If you have or know the information
> where I can find it on the web, please let me know.
> (I have trying to search it on the Internet, but no result). > Thanks alot.
>
> Mohamad Alifikri
>
> --------------------------------





Does somebody can point to good (easy) references to EVRC?

Thanks,

Sara khaled el-maleh <> wrote:

> Do not forget to read about the CDMA Enhanced Variable Rate Vocoder
> (EVRC), and the Q13 CDMA vocoder.
>



IS-127 from TIA/EIA.

wrote:

> Does somebody can point to good (easy) references to EVRC?
>
> Thanks,
>
> Sara
>
> khaled el-maleh <> wrote:
>
> > Do not forget to read about the CDMA Enhanced Variable Rate Vocoder
> > (EVRC), and the Q13 CDMA vocoder.
> >
>
>





Hi ..

If someone wants to read the details of the EVRC coder, then he has
to contact the TIA (North America Telecommunications Industry
Association) to buy the EVRC document:

TIA/EIA, TR45 (1996). Enhanced variable rate codec, speech service option
3 for wideband spread spectrum systems, Interim Standard IS-127.

The only reference that talks about the EVRC coder is a recent article
from Lucent (key designer of the EVRC coder) that appeared in the May 1999
issue of the International Journal of Speech Technology:

M. C. Recchione, "The Enhanced Variable Rate Coder: Toll Quality Speech
for CDMA", International Journal of Speech Technology, Vol. 2, No. 4, May
1999, pp. 305-315. (Kluwer Academic Publishers)

Note: This is a recommended issue for the speech coding community as it
is a speical issue containing good number of state-of-the-art speech
coding papers written by known names in the field. -----------------------------
Khaled El-Maleh
Department of Electrical & Computer Engineering
McGill University
3480 University St.
Montreal Quebec
H3A 2A7 Canada

Telephone: (514) 398-5233 (O)
Fax : (514) 398-4470
-----------------------------

On Mon, 18 Oct 1999 wrote:

> Does somebody can point to good (easy) references to EVRC?
>
> Thanks,
>
> Sara > khaled el-maleh <> wrote:
>
> > Do not forget to read about the CDMA Enhanced Variable Rate Vocoder
> > (EVRC), and the Q13 CDMA vocoder.
> >
> >
>

-----------------------------
Khaled El-Maleh
Department of Electrical & Computer Engineering
McGill University
3480 University St.
Montreal Quebec
H3A 2A7 Canada

Telephone: (514) 398-5233 (O)
Fax : (514) 398-4470