Re: [Linphone-users] mediastramer timers

[Simon Morlat]

Hello,

First of all, I do not recommend anyone to use old versions like 0.10.2. The 
current stable release is 1.0.1 .
It is not recommended to change the mediastreamer timer value.
Your snd_card_can_read() should return true only if a buffer is ready to be 
read() (ie the soundcard has captured a buffer of blocksize bytes)
It is normal that the snd_card_read() and snd_card_write() be called with 
blocks of multiple of 512 bytes, while the timer ticks every 20 ms.
The MSTimer and your soundcard clock are decorelated, that's the way it should 
work.
Your environment is quite complex, I cannot help you more. I hope those 
advices will help you to find your problem yourself.

Simon

Le Mercredi 11 Mai 2005 11:38, Amita Maheshwari a écrit :
> Hi,
>   I have compiled linphone 0.10.2 for powerpc.For RTP I am using my own
> hardware device which is a 16-bit Linear PCM codec sampling rate 8KHz. When
> I run linphonec on my ppc platform, I notice that the snd_card_read() and
> writ e functions are not called at intervals of 20ms which was set in
> linphone.The processor is running at 40MHz.So there may be some issue with
> MIPS. And since I am not reading data from the sound device at the rate it
> is writing(160 samples in 20ms), I run short of Rx buffers in my codec
> driver.Also as write to device is slow, but my codec comes more frequently
> to read the data,I can hear cutted voice. Is there some mechanism to change
> the time interval of the mediastramer timers? I could not understand the
> timer configuration and functionality. Does time interval between two
> successive reads(writes) depend on the block size(granularity)? Can
> somebody help me out ? If I change the granularity to a lower value (say
> 128 bytes), will  it help. In that case do I need to change the MSRead
> granularity and Fifo too..How these things are taken care on ARM, which
> also runs at a slower rate than PC.
>
> Thanks in advance
> Amita