Auto Crop Black from Live Video?

[shermanpat]

Looking to auto crop black from a video input. As in remove letter boxed blacks from a video input. Can anyone point me to the nodes I should be working with?

I was thinking do some edge detection but didn't see how to get the value of where the edge is.
Find find first non black pixel from each edge of the input. Just not sure what node would test specific pixels of a texture.

I need to crop the area not just make it transparent, also need to have some Data that will tell me if it is cropping or not.

Also looking to find a predefined marker on the video input. This might also be able to use pre-defined cropping styles needed for each video feed.

Thanks.

[Christian Krix Schmidt]

I think that is something Ventuz4 will let you do with a small Shader. I saw a shader example a while back - I think Karol posted it - that showed live video being accessed and processed in a Shader.

[shermanpat]

*goes digging around in karols posts*

[chriss0212]

not the best...but maybe this?

greetz

christian

[chriss0212]

oh...i misunderstood your request...

for this i dont have a solution

greetz

christian

[ErikB]

Fot this, you will have to write a shader at the very least. You are going to have to do image input processing, i.e. feed the input into a texture, then run a shader on it to detect large areas close to the edge that are black, then determine how far they go. Not trivial to say the least. Nodes alone will not get you there, I am afraid.

[shermanpat]

Thanks for the tips. I think it will be a while before i can tackle the shader stuff.