IDeckLinkMutableVideoFrame SetBytes()?

After creating a blank IDeckLinkMutableVideoFrame, how do I populate its frame bytes buffer? It isn't clear from DeckLinkAPI.h how I should do this? There is an obvious GetBytes function, which is demonstrated in the sample code, but there is no corresponding function to set the buffer. The following starting code is working fine:

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    IDeckLinkMutableVideoFrame* frame = NULL;
    result = deckLinkOutput->CreateVideoFrame(width, height, rowBytes, pxlFmt, flags, &frame);


...but now what? How do I jam the actual pixel buffer in?

Thanks.

Actually, now that I think about it, GetBytes() returns a handle, not a pointer. Maybe the intent is to simply call GetBytes() to get that handle and copy the frame buffer address into the handle...or something to that effect?

I don't have it working yet though. I tried this (which looks syntactically unlikely. I doubt this is the intended approach):

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    void *frameBytesNew = NULL;
    frame->GetBytes(&frameBytesNew);
    *(char**)frameBytesNew = (char*)frameBytes;


Where frameBytes obviously holds the pixel data I'm trying to insert into the frame. I'm not sure how to do this. Any thoughts?

[Cameron Nichols]

Hi Keith,

Actually IDeckLinkMutableVideoFrame::GetBytes will return a pointer to the allocated buffer for the video frame. You can then fill the buffer with memcpy or otherwise. You cannot just copy the address of another buffer.

However if you are looking for a zero-copy solution, you can wrap your existing buffer (frameBytes) into a class that implements IDeckLinkVideoFrame. Implement all required methods, your ::GetBytes() will output the pointer to your buffer.

You can find examples of this in FilePlayback samples (Win - PlaybackVideoFrame, Mac - DeckLinkCoreMediaVideoFrame).

Regards
Cameron