Hi Laurent, 

Thanks for your reply. Well I know that H.264 payload is specified in newer UVC 
1.1 documentation, but my webcam is not sending H.264 as payload. Its sending 
MPEG2-TS according to UVC1.0 secifications, i found out during debugging, 
format descriptor gives 0x0A as Descriptor subtype. 

As per old archives from mailing list i added MPEG2-TS handling similar to DV 
format. I am now able to create a /dev/video device on my machine but i have no 
idea how to add stream support to UVC-v4l2 interface or where to add that 
support. As there is no frame descriptor V4L2 driver is not able to detect the 
frame rate etc... Maybe i am getting little confused here? 

Regards, 
Ajay 


----- Original Message ----- 
From: "Laurent Pinchart" <[email protected]> 
To: [email protected] 
Cc: "Ajay Bhargav" <[email protected]>, "Paulo Assis" 
<[email protected]>, "Kofi Jedamzik" <[email protected]> 
Sent: Wednesday, June 22, 2011 6:21:09 AM 
Subject: Re: [Linux-uvc-devel] Webcam with H264 encoder not in Devicelist 

Hi, 

On Thursday 16 June 2011 11:09:51 Ajay Bhargav wrote: 
> Hi Paulo, 
> 
> I have the pdf document of the same. But the thing is my camera is UVC V1.0 
> and actual format coming from camera is H.264 encoded stream in MPEG2-TS 
> format. So i will have to look for only MPEG2-TS support. I hope i am 
> going in right direction. As per my UVC traces, the video streaming format 
> is 10 which is MPEG2-TS. 
> 
> @Laurent, Please provide me some information so i can move ahead. 

H.264 UVC payloads have been implemented in various webcams before the 
official H.264 UVC payload spec got released. Those implementations are not 
documented, and not supported by the driver. Without documentation from the 
manufacturer, H.264 encoder parameters won't be supported. 

The official H.264 UVC specification isn't better. Its only purpose is to 
support Logitech webcams in Skype under Windows. Its quality is way below what 
I would expect from a USB-IF specification. I don't plan to implement support 
for that spec in the uvcvideo driver in the near future. I'll review patches, 
but I will NAK anything that isn't clean enough. And from reading the spec 
producing a clean implementation will be pretty difficult. 

-- 
Regards, 

Laurent Pinchart 


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