[Asterisk-video] Audio stream shortenings with some mobile phones(using mp4save)

Sergio Garcia Murillo sergio.garcia at fontventa.com
Thu Feb 14 10:02:05 CST 2008


Hi Florian,

Yes it seems that the audio is recorded contiguous even if the have silence pauses in between.
I'll have to check if the problem is in mp4save or app_h324m (I think it's in the latest one).
Could you fill a bug in the tracker?

Best regards
Sergio

----- Original Message -----
From: Florian Greb [mailto:florian.greb at viif.de]
To: asterisk-video at lists.digium.com
Sent: Thu, 14 Feb 2008 17:40:17 +0100
Subject: [Asterisk-video] Audio stream shortenings with some mobile phones(using mp4save)

Hello,
during my tests I discovered a serious problem using mp4save. 
With some mobile phones, audio data is far from being synchronous. The
worst test results we had were from a Motorola KRZR K3. A one minute
recording had audio already finished after 40 seconds, the video playing
all the 60 seconds. The bug is clearly on the receiving part, as the
files created had these defects.
The tests were done counting every some seconds alound in front of the
camera. Especially speaking pauses were shortened drastically! After
replacing the speak (which includes pauses between the numbers) by a
simple constant sinus tone the defects were gone. 
Mobile phones don't send audio data if there is only noise to transmit.
How is it handled? Maybe this is the place to look for the bug. 
Ideas, anybody?


Tested phones:
---------------
SonyEricsson P1	  - no shortenings
Nokia 6233 / 6234 - nearly no shortenings
Nokia 6680	  - small shortenings (1-2 sec. missing out of 60)
SonyEricsson K800i - substantial shortenings (~6 sec. missing out of 60)
Motorola KRZR K3 - huge shortenings (~20 sec. missing out of 60)

Kind regards,

Florian

_______________________________________________
--Bandwidth and Colocation Provided by http://www.api-digital.com--

asterisk-video mailing list
To UNSUBSCRIBE or update options visit:
   http://lists.digium.com/mailman/listinfo/asterisk-video



More information about the asterisk-video mailing list