UVC with 2 output ISO streams

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Anonymous
Not applicable

 Hi,

   

is it possible to have UVC devices with 2 output ISO streams but not as composite devices. My goal is to have just 1 device which I can load by DirectShow (for example by Graph Edit) and this device should have 2 the same output pins (capture).

   

 

   

If so, should it has:

   

A) 1 Output Terminal with 2 ISO interfaces binded to it or

   

B) 2 Outpin Terminals with 1 ISO interface each?

   

 

   

Thanks in advence for your help.

   

 

   

BTW, is there any USB forum on Internet, where I can put such questions. I know only https://www.usb.org/phpbb/ which is inaccessible because (as far as I know) it was closed about 2 years ago.

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2 Replies
Anonymous
Not applicable

Hi Piotr,

Since the VS Input Header descriptor only supports one bEndpointAddress I think you would have to present this as two VideoStreaming interfaces, i.e. bInCollection = 2 in the VC Interface Header descriptor.  

So, you would provide one Output Terminal and two sets of Video Streaming descriptors.

Even with this, I don't think there's anything preventing the host from doing a probe/commit sequence on the second interface that conflicts with the settings required for the first - unless your interface is such that no configuration is allowed.

You might try these folks for a more definitive answer:

uvcdisc@microsoft.com

   

https://lists.sourceforge.net/lists/listinfo/linux-uvc-devel

Regards,
Steve 

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Anonymous
Not applicable

 Hi,

   

 

   

I did not get how you can handle two interfaces using same O/P terminal? If you had two streaming interfaces for one video source, how would you adjust video properties of both the sterams individually? Please excuse, if I did not understand your app well. I think 1O/P terminal must be mapped to 1 IISO interface. Can you please detail your app a bit more.

   

 

   

Regards,

   

Gayathri

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