I am not sure if it is the right forum to ask this. Please help point me to right direct if i am wrong.
I need to write a UVC1.5 compliant device with multiple streaming interfaces. The streams are all of custom formats.
Can I create a single function with multiple CT+Streaming interfaces?
IS there a off the shelf video device which is UVC complaint and has multiple streaming interfaces?
Are there any WHCK related requirements I should be aware of?
xxxxx@yahoo.com wrote:
I am not sure if it is the right forum to ask this. Please help point me to right direct if i am wrong.
I need to write a UVC1.5 compliant device with multiple streaming interfaces. The streams are all of custom formats.
Can I create a single function with multiple CT+Streaming interfaces?
IS there a off the shelf video device which is UVC complaint and has multiple streaming interfaces?
Are there any WHCK related requirements I should be aware of?
Your terminology is a bit confusing, but each pair of UVC interfaces is
a completely independent device as far as Windows is concerned. You can
have as many as you need. That isn’t commonly done, because you run out
of bandwidth very quickly. It IS very common, however, to have a UVC
device and a UAC device together, for a camera plus microphone. Same
concept.
–
Tim Roberts, xxxxx@probo.com
Providenza & Boekelheide, Inc.
Thanks for your reply.
These are very low bandwidth streams within USB 3 capability.
I need to support multiple streaming interfaces in a single USB device. These UVC interfaces may or may not be independent. Some streams can be independently started and stopped while others have a dependency where stopping one would stop another due to HW limitation.
So I think I need to club those that are dependent and keep the one’s independent as separate. I have fair idea of what needs to be done to create multiple instances of streaming interfaces. What I am not sure is how to combine multiple streaming interfaces together as single devices? Can you point me to a device with such a descriptor or some direction to where to start?
On May 20, 2015, at 1:30 PM, xxxxx@yahoo.com wrote:
I need to support multiple streaming interfaces in a single USB device. These UVC interfaces may or may not be independent. Some streams can be independently started and stopped while others have a dependency where stopping one would stop another due to HW limitation.
How do you think this would be used? You can certainly have one filter that exposes multiple output pins, and each of those pins can be consumed separately, but all of the pins would be part of a single application. With multiple filters, each filter could be opened from a different application. You will, however, have the problem of figuring out which is which.
So I think I need to club those that are dependent and keep the one’s independent as separate. I have fair idea of what needs to be done to create multiple instances of streaming interfaces. What I am not sure is how to combine multiple streaming interfaces together as single devices? Can you point me to a device with such a descriptor or some direction to where to start?
I assume you already have a couple of USB web cameras, so you can see what a simple descriptor set looks like. Every Video Control interface represents a separate filter — a separately controllable stream. The Video Control interface descriptors describe the graph of components that make up the camera. Often, it’s just a “camera input” node, a “video control” node, and a “streaming output” node. The “streaming output” node then points to the Video Streaming interface that exposes the streaming endpoints.
However, the node graph in the Video Control endpoint can be more complicated, and can include multiple “streaming output” nodes. Each “streaming output” node points to a separate Video Streaming interface, each of which can have its own set of formats.
A single Video Control interface with multiple Video Streaming interfaces will be exposed as a single filter with multiple output pins.
—
Tim Roberts, xxxxx@probo.com
Providenza & Boekelheide, Inc.
Thanks a lot for taking the time out and replying.
That’s all I needed 