On Thu, Sep 3, 2009 at 3:12 PM, Giovanni Maruzzelligmaruzz.lists@gmail.com wrote:
On Thu, Sep 3, 2009 at 3:05 PM, Clemens Ladischclemens@ladisch.de wrote:
It would be easier to try to change the constraints of the sound card that snd-dummy tries to emulate; set USE_PERIODS_MIN to four or so, and increase period_bytes_min to some value that is at least as large as the numer of bytes per timer tick (with 2 channels and 16 bits at 48 kHz, there are 192000 bytes per second).
I put a printk that prints the contents of runtime struct at the last line of the snd_card_dummy_pcm_prepare() function, so to know how Skype client uses the soundcard.
The result are: Sep 3 16:11:04 localhost kernel: 253, cicopet1 rate=16000 channels=2, period_size=2048, periods=2, buffer_size=4096, timer_resolution=128000000 Sep 3 16:17:42 localhost kernel: 253, cicopet1 rate=16000 channels=2, period_size=2048, periods=2, buffer_size=4096, timer_resolution=128000000 Sep 3 16:17:42 localhost kernel: 253, cicopet1 rate=16000 channels=2, period_size=2048, periods=2, buffer_size=4096, timer_resolution=128000000 Sep 3 16:17:42 localhost kernel: 253, cicopet1 rate=16000 channels=1, period_size=2048, periods=2, buffer_size=4096, timer_resolution=128000000 Sep 3 16:17:42 localhost kernel: 253, cicopet1 rate=16000 channels=1, period_size=2048, periods=2, buffer_size=4096, timer_resolution=128000000
So, it seems that it opens 2 channels for playback and one channel for capture, at 16k
What's the best values for constraints you counseil?
-giovanni