To manipulate a video so that only the red channel is visible and the other channels (green and blue) are set to black using FFmpeg, you can use the following command. This command utilizes the geq filter to manipulate the color channels directly:
ffmpeg -i input.mp4 -vf "geq=r='p(X,Y)':g='0':b='0'" -c:a copy output.mp4
Here’s a breakdown of the command:
-i input.mp4: Specifies the input video file.-vf "geq=r='p(X,Y)':g='0':b='0'": Applies the geq (graphical equalizer) filter to process the video frames.
r='p(X,Y)': This keeps the red component of each pixel as is (p(X,Y) refers to the pixel value at position (X, Y) in the input).g='0': Sets the green component of each pixel to 0, effectively turning it black.b='0': Sets the blue component of each pixel to 0, also turning it black.
-c:a copy: Copies the audio from the input file without modification.output.mp4: Specifies the output file.
Make sure you have FFmpeg installed on your system to run this command. This will generate a new video where only the red channel is visible, and the other color channels are black.