I Prompted ChatGPT: In terms of video compression, what's "crf"?
The -crf
(Constant Rate Factor) is a parameter in FFmpeg that controls the quality of the video when using lossy compression (such as H.265 or H.264). It sets the balance between video quality and file size.
Here’s how it works:
- Lower CRF values mean higher quality (and larger file sizes).
- Higher CRF values mean lower quality (and smaller file sizes).
For H.265, the typical CRF range is 18–28:
- 18: Almost lossless quality (very high quality, large file size).
- 23: Default and good balance between quality and size.
- 28: Lower quality (smaller file size).
In the example script, -crf 23
is used because it's often considered a good trade-off for retaining quality without excessively increasing file size. You can adjust it based on your preference for quality vs. size.