blind-set-luma - Multiply the luminosity of a video
blind-set-luma luma-stream
blind-set-luma reads a video from stdin and a mask video from luma-stream. The video is printed to stdout, with the luminosity of each pixel multiplied by the product of the luminosity and the alpha value of the corresponding pixel and frame in the mask video.
If stdin is longer than luma-stream, the remainder of stdin is printed without any changes. If stdin is shorter than luma-stream, the remainder of luma-stream is ignored but may be partially read.
In most cases, this is not what you want to use, instead you probably want to use blind-arithm(1) to multiple the X, Y and Z values on one value. This produces the same affect as reducing the intensity of the light sources, which is not what blind-set-luma does.
blind(7), blind-single-colour(1), blind-arithm(1), blind-set-alpha(1), blind-invert-luma(1), blind-set-saturation(1)
Mattias Andrée <[email protected]>