Subject: [AVT] H264 Frame rate

From: "Ajmal, Humayun" <[email-masked]>
Date: Thu, 7 Jun 2007 20:48:55 +0500

Hi list, 

H264 codec information received in SDP don't provide frame rate. With
given parameters (clock rate and bandwidth or another), is there anyway
frame rate can be calculated?

Thanks 

Humayun

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

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From: "Even, Roni" <[email-masked]>
Date: Thu, 7 Jun 2007 19:22:34 +0300

Hi,

Look at max-mbps, max-fs attributes. Using the maximum macro blocks per
second and maximum frame size you can calculate the frame rate

Roni Even

________________________________

From: Ajmal, Humayun [mailto:[email-masked]] 
Sent: Thursday, June 07, 2007 6:49 PM
To: [email-masked]
Subject: [AVT] H264 Frame rate

Hi list, 

Thanks 

Humayun

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From: Randell Jesup <[email-masked]>
Date: Thu, 07 Jun 2007 21:35:51 -0400

>second and maximum frame size you can calculate the frame rate

Not the actual frame rate, but the maximum possible frame rate at the
maximum frame size.  A receiver may support a higher frame rate at a lower
frame size, and it may be proportional to max-mbps/actual-frame-size, but
nothing directly tells you the frame rate that can be displayed.

I.e., with an implementation that supports 30fps @CIF, in theory it may
support 120fps @ QCIF, but there's no guarantee it will be able to display
120fps.  Also, there's undoubtably per-frame overhead, so max-mbps is only
a rough approximation of the decoders capabilities.

-- 
Randell Jesup, Worldgate (developers of the Ojo videophone), ex-Amiga OS team
[email-masked]
"The fetters imposed on liberty at home have ever been forged out of the weapons
provided for defence against real, pretended, or imaginary dangers from abroad."
		- James Madison, 4th US president (1751-1836)

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From: sona chalam <[email-masked]>
Date: Fri, 8 Jun 2007 07:40:52 -0700 (PDT)

Hi

How to identify a Start  and End of a FRAME in H264
using NAL units.

I am performing H264 streaming  and  extracting NAL
units from RTP packets .

My understanding is one Access unit is called as a
FRAME.

In my streaming session I am receiving FUA and SNAL
only.  I am not geting any other NAL unit types  other
than 1 and 5).

So how to construct access unit in this case?

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