[Speex-dev] running speex on C5505, anybody tested the quality of voice?

Vijay Gabale vijay.gabale at gmail.com
Sat Jul 24 04:53:37 PDT 2010


Hi,

I am working on a project which intends to enable voice communication over
zigbee.
As the handset node, I am using TI's C5505 ezDSP USB stick. I want to run
speex encoder on it. After encode, I intend to send it over CC2520 radio to
the backend zigbee network.

The C5505 ezDSP has input and output for AIC3204 codec which I am using to
give sampled input from laptop (lineout) and playback output to headphones.

Find my code here (http://www.cse.iitb.ac.in/~vijaygabale/temp/speex/,I have
put in lot of efforts in putting together this piece of code, if you reuse
it, please let me know) which has DMA interrupts enabled to sample AIC3204
every 20ms,  ping pong buffering implemented (both at sample and playback
side) and open source speex integrated to sample-encode-decode-playback the
samples.

However, I find quality of speex encoder very bad. If I disable the only the
speex encode and decode calls (comment out code in while loop in mail.c) and
play the sampled voice (at 8Khz), I can hear a good quality voice (this
means that DMA interrupts and ping-pong buffering is working smoothly
simultaneoulsy). I don't think the calls consumes too many MIPS
(instructions) and even if they do, I should be able to hear good quality
voice.

I don't know if anybody has tested the quality of voice on C5505 for
real-time communication, but if you could just go through main.c file of the
project, you should see the speex initialization and encode, decode part. If
you figure out anything specific, do let me know. If you are struggling on
same issue, I would be happy if you try out the code.

I would be highly obliged to get help as I am running behind the deadlines.

Thanks.

Regards,
Vijay
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.xiph.org/pipermail/speex-dev/attachments/20100724/6ced0114/attachment.htm 


More information about the Speex-dev mailing list