Re: latency.c: some feature requests

[Lee Revell <rlrevell@joe-job.com>]

On Sun, 2004-11-28 at 19:44 +0100, Jaroslav Kysela wrote:
> -P plughw:0,3 -C plughw:0,2

Thanks.  Here are the results.  Does this look OK to you?

It looks like the playback runs 64 frames ahead of the capture.  Do you
think this would be a problem from the application's perspective?

rlrevell@mindpipe:~/cvs/alsa-cvs-T3/alsa-lib/test$ ./latency -P plughw:0,3 -C plughw:0,2 -c 16 -r 48000
Scheduler set to Round Robin with priority 99...
Playback device is plughw:0,3
Capture device is plughw:0,2
Parameters are 48000Hz, S16_LE, 16 channels, non-blocking mode
Wanted tick time: 0us, poll mode: no
Loop limit is 1440000 frames, minimum latency = 64, maximum latency = 4096
Plug PCM: Copy conversion PCM
Its setup is:
stream       : PLAYBACK
access       : RW_INTERLEAVED
format       : S16_LE
subformat    : STDI still have not implemented synced start so it looks like the capture and playback are a little out of sync.  
channels     : 16
rate         : 48000
exact rate   : 48000 (48000/1)
msbits       : 16
buffer_size  : 64
period_size  : 32
period_time  : 666
tick_time    : 1000
tstamp_mode  : NONE
period_step  : 1
sleep_min    : 0
avail_min    : 4
xfer_align   : 4
start_threshold  : 2147483647
stop_threshold   : 64
silence_threshold: 0
silence_size : 0
boundary     : 1073741824
Slave: Hardware PCM card 0 'Sound Blaster Audigy2' device 3 subdevice 0

Its setup is:
stream       : PLAYBACK
access       : MMAP_NONINTERLEAVED
format       : S16_LE
subformat    : STD
channels     : 16
rate         : 48000
exact rate   : 48000 (48000/1)
msbits       : 16
buffer_size  : 64
period_size  : 32
period_time  : 666
tick_time    : 1000
tstamp_mode  : NONE
period_step  : 1
sleep_min    : 0
avail_min    : 4
xfer_align   : 4
start_threshold  : 2147483647
stop_threshold   : 64
silence_threshold: 0
silence_size : 0
boundary     : 1073741824
Plug PCM: Hardware PCM card 0 'Sound Blaster Audigy2' device 2 subdevice 0

Its setup is:
stream       : CAPTURE
access       : RW_INTERLEAVED
format       : S16_LE
subformat    : STD
channels     : 16
rate         : 48000
exact rate   : 48000 (48000/1)
msbits       : 16
buffer_size  : 64
period_size  : 32
period_time  : 666
tick_time    : 1000
tstamp_mode  : NONE
period_step  : 1
sleep_min    : 0
avail_min    : 4
xfer_align   : 4
start_threshold  : 2147483647
stop_threshold   : 64
silence_threshold: 0
silence_size : 0
boundary     : 1073741824
Trying latency 64 frames, 1333.333us, 1.333333ms (750.0000Hz)
Success
Playback:
*** frames = 1440080 ***
state       : RUNNING
trigger_time: 1101676443.293035000
tstamp      : 1101676473.295128000
delay       : 59
avail       : 5
avail_max   : 15
Capture:
*** frames = 1440016 ***
state       : RUNNING
trigger_time: 1101676443.293030000
tstamp      : 1101676473.295506000
delay       : 52
avail       : 52
avail_max   : 52
Maximum read: 32 frames
Maximum read latency: 666.667us, 0.666667ms (1500.0000Hz)
Playback time = 1101676443.293035, Record time = 1101676443.293030, diff = 5

Lee



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