How to do USB Video

Since the great success of Colin/Dave and Jim with USB audio – perhaps something could be done with USB video input.

ie Video Cams and presumably the same input is used with USB oscilloscopes.

I’m sure the isochronous transfer mode will allow video to be got in from a webcam. But how are we going to process that video once it’s in?

I can think of many situations where editing is not required.
Streaming live, saving and playing would be a very useful start.

When saving video, is it acceptable and sufficient to simply store the USB payload?

It’s a naive question.

I am aware that simply recording the RTP payload of an H.264 video stream of a SIP audio+video call does not produce a file that can be replayed meaningfully.

file that can be replayed

Is that an intentional pun, Dave?

Is that an intentional pun, Dave?

Sorry, no :-(

Don’t know anything about Video streams but Audio streams need to be fault tolerant because isochronous streams are not error checked (bulk streams are error checked and retried if the error check fails) It’s easy to see how Audio streams are fault tolerant – a modified PCM sample won’t cause a program processing it to crash. I can’t see a camera transfering a block of pixels every packet, which would be the equivalent to PCM in audio. It’ll be interesting to see the solution.

It looks like a lot of reading is necessary – I’ll give it a pass at the moment :-)