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8. Not Your Father’s TV: Video ...With S... > How to process the buffer
How to process the buffer
We’ve got our hands on a frame of video data, so let’s do some processing on it! To process the frame, we’re going to loop over every single pixel in the frame data and pull out the RGB color values that are stored in each pixel. Actually, each pixel has 4 values, RGB and Alpha (the opacity), but we’re not going to use the Alpha. Once we’ve got the RGB values, we’ll call the effectFunction (remember, that’s the function we set back in How video processing works and asked you to tuck in the back of your brain!) with the RGB information and the frame.
Add this code to the bottom of your processFrame function:
Yes, that’s one single frame we just processed, and we want to keep processing them all as the video continues to play. We can use setTimeout and pass it a value of zero milliseconds to ask JavaScript to run processFrame again as soon as it possibly can. JavaScript won’t actually run the function in zero milliseconds, but it will give us the next soonest time slot we can get. To do that, just add this to the bottom of your processFrame function:
