Talking clock - timestamp problem?

[David Holroyd]

On 20/08/14 23:11, Tim Müller wrote:
> On 18/08/14 22:11, David Holroyd wrote:
>> I am trying to build a pipeline something like a 'talking clock',
>> continually announcing the current date and time as test input to
>> another system.
>>
>> The pipeline I've built in Ruby (bindings via gir_ffi) looks like:
>>
>>    appsrc ! festival ! wavparse ! audioconvert ! audioresample
>>      ! audio/x-raw,rate=48000,channels=2 ! audioconvert ! rtpL24pay
>>      ! udpsink

> Perhaps have two separate pipelines, connected via interaudiosink/src
> elements:
>
>    interaudiosrc ! ... ! rtpL24pay ! udpsink
>
> and then
>
>    appsrc ! festival ! wavparse ! ... ! interaudiosink
>
> (where ... = audioconvert ! audioresample)

> Otherwise, there's also gst_pad_set_offset().

Fantastic!  I was not aware of either of these mechanisms.

I almost have interaudio* working, but with much audio popping.

When I run the pipelines with GST_DEBUG=4, I see that interaudiosrc is 
inserting silence inbetween pieces of audio,

0:00:11.848882460  8197  0x267d5e0 WARN   interaudiosrc 
gstinteraudiosrc.c:282:gst_inter_audio_src_create: flushing 800 samples
0:00:11.948906569  8197  0x267d5e0 WARN   interaudiosrc 
gstinteraudiosrc.c:282:gst_inter_audio_src_create: flushing 800 samples
0:00:12.048877221  8197  0x267d5e0 WARN   interaudiosrc 
gstinteraudiosrc.c:300:gst_inter_audio_src_create: creating 512 samples 
of silence
0:00:12.083871396  8197  0x267d5e0 WARN   interaudiosrc 
gstinteraudiosrc.c:282:gst_inter_audio_src_create: flushing 800 samples
0:00:12.183945130  8197  0x267d5e0 WARN   interaudiosrc 
gstinteraudiosrc.c:300:gst_inter_audio_src_create: creating 1056 samples 
of silence
0:00:12.213834049  8197  0x267d5e0 WARN   interaudiosrc 
gstinteraudiosrc.c:282:gst_inter_audio_src_create: flushing 800 samples
0:00:12.313945515  8197  0x267d5e0 WARN   interaudiosrc 
gstinteraudiosrc.c:300:gst_inter_audio_src_create: creating 1056 samples 
of silence
0:00:12.348859357  8197  0x267d5e0 WARN   interaudiosrc 
gstinteraudiosrc.c:282:gst_inter_audio_src_create: flushing 800 samples
0:00:12.448882559  8197  0x267d5e0 WARN   interaudiosrc 
gstinteraudiosrc.c:300:gst_inter_audio_src_create: creating 1056 samples 
of silence
0:00:12.483832142  8197  0x267d5e0 WARN   interaudiosrc 
gstinteraudiosrc.c:282:gst_inter_audio_src_create: flushing 800 samples
0:00:12.583931457  8197  0x267d5e0 WARN   interaudiosrc 
gstinteraudiosrc.c:300:gst_inter_audio_src_create: creating 1056 samples 
of silence
0:00:12.613845047  8197  0x267d5e0 WARN   interaudiosrc 
gstinteraudiosrc.c:282:gst_inter_audio_src_create: flushing 800 samples
0:00:12.713836859  8197  0x267d5e0 WARN   interaudiosrc 
gstinteraudiosrc.c:300:gst_inter_audio_src_create: creating 1056 samples 
of silence
0:00:12.748878419  8197  0x267d5e0 WARN   interaudiosrc 
gstinteraudiosrc.c:282:gst_inter_audio_src_create: flushing 800 samples
0:00:12.848877876  8197  0x267d5e0 WARN   interaudiosrc 
gstinteraudiosrc.c:282:gst_inter_audio_src_create: flushing 800 samples
0:00:12.948874678  8197  0x267d5e0 WARN   interaudiosrc 
gstinteraudiosrc.c:300:gst_inter_audio_src_create: creating 512 samples 
of silence

I have tried (unscientifically) putting queue elements in various places 
on the assumption this happens because of buffer underflows somewhere, 
but that's not helped so far.

Any ideas?


Many thanks!
dave