2 Replies Latest reply on May 23, 2012 5:50 AM by GayathriV_16

    UVC with 2 output ISO streams



      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.

        • 1. Re: UVC with 2 output ISO streams

          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:





          • 2. Re: UVC with 2 output ISO streams





            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.