'Twas brillig, and ANISH KUMAR at 06/04/10 12:37 did gyre and gimble:

As my question is related to the query what pradeep is asking and mark brown also suggested to me to use PA. I have some additional questions regarding PA which i would like to clarify before starting:

1.Does PA have good resampler code if my hardware doesn't support resampling?

Yes. Infact this code will likely be needed in several cases when the h/w does support resampling. If PA has multiple streams playing at once, the h/w will likely only be able to cope with one rate at a time.

The resamplers are pluggable and can have optimized implementation for some hardware - e.g. I believe Palm wrote an ARM specific resampler to do this for their Pre platform (I could be mis-remembering tho').

I have a system where we are using ALSA as the base and on top(application side) of it there is a thread running which is pumping data and this thread is started by java code.Combination of LINUX+JAVA. This thread can perform these tasks: 1.Resampling for some rates. 2.Talking to PV framework to get the decoded PCM data and pumping audio data to alsa. 3.Routing support using asound.conf file. Can i replace this thread with PA by writing some wrapper over PA?? What extra features PA is going to provide additionally if i start using PA other than what is listed above??As i know PA is kind of sound deamon which my thread is not.

One very interesting feature of PA that is particularly relevant to mobile platforms is the use of a timer-based model to drive the hard ware. This allows for very large latencies to be used (e.g. 10-20s) allowing for very efficient processor usage - only waking up when absolutely necessary, not to service interrupts.

More info: http://0pointer.de/blog/projects/pulse-glitch-free.html

This approach can bring power savings and thus increased battery life.

Is there any good resampler code which i can use without any licensing problem and which can be easily integrated???

I pretty sure the included resamplers are OK to use, but it's all clearly documented so just take a look.

Like I say it's easy enough to include your own too if needs be.

Col