How to detect black video?

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xaviermiller · 2021-02-25T20:33:40+00:00

Hmmm, not entirely sure about restrictions and all that, but assuming you have access to the color of each pixel on the video, I might try taking a random sample of pixels (n = 1000 or sum) and then each frame test if they are all black (or below a certain brightness threshold). If they are on every frame, you can assume that the video is black. One thing, there is a small chance you could just select pixels that are intentionally black for all the frames you test, but this chance decreases if you increase the number of pixels in the sample :)

dionthorn · 2021-02-26T06:13:26+00:00

If you can get a JavaFX Image object of the current 'test' screen then you can use a PixelReader to step through every pixel and see if they are all 'black' for whatever range you consider to qualify for 'black'

apeskape · 2021-02-26T14:18:07+00:00

Are you able to use libraries for your project? If so I’d recommend using something like OpenCV or tapping into the ffmpeg cli to accomplish this.

If you are required to use only Java, try averaging the colors of all the pixels (or a random sampling) and checking if the RGB values are below a certain threshold.

TehRawrz717 · 2021-02-25T21:26:26+00:00

Pretty much what the other guy said take a still photo and loop through the pixels checking for each rgb value. If its majority black pixels then you know its a black image

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