[Bluez-users] A2dp on ARM9- Quality not good

[Bluez-users] A2dp on ARM9- Quality not good

[Sumeet VERMA]

Hi 
I have cross compiled the bluez stack-3.11 and btsco-0.42 for ARM9 platform. The audio streaming is working using the a2play application but the voice quality is not good. There are lot of breaks. The same setup is working fine on the PC.

I think the problem is due to the MIPS available for SBC encoding. ARM9 is running at 133 MHz. 
Can you please suggest some optimizations which would help me improve the audio quality?

Thanks and Regards,
Sumeet 


-------------------------------------------------------------------------
This SF.net email is sponsored by: Splunk Inc.
Still grepping through log files to find problems?  Stop.
Now Search log events and configuration files using AJAX and a browser.
Download your FREE copy of Splunk now >>  http://get.splunk.com/
_______________________________________________
Bluez-users mailing list
Bluez-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/bluez-users

Re: [Bluez-users] A2dp on ARM9- Quality not good

[Brad Midgley]

Sumeet,

first, try different encoder settings. some settings use more
bandwidth but less cpu.

also see the todo items from sbc.c:

  use a log2 table for byte integer scale factors calculation (sum
log2 results for high and low bytes)
  fill bitpool by 16 bits instead of one at a time in bits
allocation/bitpool generation
  port to the dsp
  don't consume more bytes than passed into the encoder

some of these were suggested to me by the guy writing an encoder for
palm 700p. I didn't dig into the algorithm to see how they would work.

Brad

-------------------------------------------------------------------------
This SF.net email is sponsored by: Splunk Inc.
Still grepping through log files to find problems?  Stop.
Now Search log events and configuration files using AJAX and a browser.
Download your FREE copy of Splunk now >>  http://get.splunk.com/
_______________________________________________
Bluez-users mailing list
Bluez-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/bluez-users

Re: [Bluez-users] A2dp on ARM9- Quality not good

[Marcel Holtmann]

Hi Brad,

> first, try different encoder settings. some settings use more
> bandwidth but less cpu.
> 
> also see the todo items from sbc.c:
> 
>   use a log2 table for byte integer scale factors calculation (sum
> log2 results for high and low bytes)
>   fill bitpool by 16 bits instead of one at a time in bits
> allocation/bitpool generation
>   port to the dsp
>   don't consume more bytes than passed into the encoder
> 
> some of these were suggested to me by the guy writing an encoder for
> palm 700p. I didn't dig into the algorithm to see how they would work.

I think that is a job for our friends from Brazil. Ping them and see if
they can work something out.

Regards

Marcel



-------------------------------------------------------------------------
This SF.net email is sponsored by: Splunk Inc.
Still grepping through log files to find problems?  Stop.
Now Search log events and configuration files using AJAX and a browser.
Download your FREE copy of Splunk now >>  http://get.splunk.com/
_______________________________________________
Bluez-users mailing list
Bluez-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/bluez-users

Re: [Bluez-users] A2dp on ARM9- Quality not good

[Brad Midgley]

Marcel

> I think that is a job for our friends from Brazil. Ping them and see if
> they can work something out.

I did send Walter an email to ask him about it.

They had talked about porting to the dsp, but the general purpose code
should be tightened up first.

Brad

-------------------------------------------------------------------------
This SF.net email is sponsored by: Splunk Inc.
Still grepping through log files to find problems?  Stop.
Now Search log events and configuration files using AJAX and a browser.
Download your FREE copy of Splunk now >>  http://get.splunk.com/
_______________________________________________
Bluez-users mailing list
Bluez-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/bluez-users

Re: [Bluez-users] A2dp on ARM9- Quality not good

[Marcel Holtmann]

Hi Brad,

> > I think that is a job for our friends from Brazil. Ping them and see if
> > they can work something out.
> 
> I did send Walter an email to ask him about it.
> 
> They had talked about porting to the dsp, but the general purpose code
> should be tightened up first.

yes, the DSP implementation is actually unimportant right now. I would
not even know how to integrate that. We need to fix the main SBC library
inside bluez-utils first.

Regards

Marcel



-------------------------------------------------------------------------
This SF.net email is sponsored by: Splunk Inc.
Still grepping through log files to find problems?  Stop.
Now Search log events and configuration files using AJAX and a browser.
Download your FREE copy of Splunk now >>  http://get.splunk.com/
_______________________________________________
Bluez-users mailing list
Bluez-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/bluez-users