[FFmpeg-user] Read single pixel value

[Joshua Grauman]

Hi all,

I'm still working on my setup and haven't gotten anywhere. Maybe 
simplifying my question will help.

Is there any way to read a single pixel value from a video on the 
commandline that can be used as a variable in other filters (ie to 
position overlays)?

If not, would there be generic template code for a function or filter in 
ffmpeg so that I could write one? I know c/c++ but have very little 
experience with ffmpeg. Would someone be able to steer me in the right 
direction to add this functionality?

Also, to write a function/filter do you have to compile all of ffmpeg, or 
is there a plugin system?

Thanks so much!!

Josh