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How to decrease video size by changing its quality?


You can call the following command using FFmpeg, which adjusts the CRF (Constant Rate Factor) and preset parameters, using the x264 encoder (H.264):

ffmpeg.exe -i input.mp4 -crf 25 -preset veryslow output.mp4

Here, 25 is used as CRF. You should choose a value between 0 and 51. Higher values indicate lower quality, so 0 is the best quality, while 51 - the worst.

As for presets, you can use one of the following: ultrafast, superfast, veryfast, faster, fast, medium, slow, slower and veryslow. The default value is medium, while you use veryslow in the command above.

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Hello, I am Marcin

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