Subject: [AVT] AC-3 audio transmission with TFRC

From: Alejandro Cabrera Obed <[email-masked]>
Date: Sat, 29 Oct 2005 22:07:28 -0300

Dear all,
 Suppose I transmit audio AC-3 over IP/UDP/RTP with congestion control using
TFRC. So I need to use the "RTP Payload Format for Audio AC-3" and the "RTP
Profile for TFRC".
 Suppose I design an AC-3 audio system that handles a sampling rate of
either 48 KHz or 44.1 KHz...........Can I take all the values from the
interval between 48 Khz and 44.1 Khz ( let's say 48, 47.9, 47.8,
47.7.....44.2, 44.1) in order match the audio rate to the calculated rate
with TFRC equation ???
 Or in the negative case, what parameter would you take in order to vary the
audio rate to match the TFRC calculated rate for congestion control ???
 Thanks in advance !!!!!
 Alejandro

--
Alejandro Cabrera Obed
[email-masked]
_______________________________________________
Audio/Video Transport Working Group
[email-masked]
https://www1.ietf.org/mailman/listinfo/avt

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From: Colin Perkins <[email-masked]>
Date: Sun, 30 Oct 2005 10:01:42 +0000

On 30 Oct 2005, at 01:07, Alejandro Cabrera Obed wrote:
> Suppose I transmit audio AC-3 over IP/UDP/RTP with congestion  
> control using TFRC. So I need to use the "RTP Payload Format for  
> Audio AC-3" and the "RTP Profile for TFRC".
>
> Suppose I design an AC-3 audio system that handles a sampling rate  
> of either 48 KHz or 44.1 KHz...........Can I take all the values  
> from the interval between 48 Khz and 44.1 Khz ( let's say 48, 47.9,  
> 47.8, 47.7.....44.2 , 44.1) in order match the audio rate to the  
> calculated rate with TFRC equation ???

No. Only clock rates of 32000, 44100 and 48000 are allowed.

> Or in the negative case, what parameter would you take in order to  
> vary the audio rate to match the TFRC calculated rate for  
> congestion control ???

I'm not sure it's possible with the AC-3 codec.

Colin