I was re-encoding videos downloaded from YouTube with Lossless H.264 (using FFmpeg) because I'm experimenting with CRF=0
.
I found that resulting videos are much bigger (1 gigabyte) than the original video (100 megabyte).
However, from my knowledge of lossy compression, it is basically like lossless compression (plus, it's the same codec) except it throws away lots of minor details that won't be noticed but take up lots of space. Hence, shouldn't I achieve a similar file size if I encode the decoded file using CRF=0
because lots of data are already thrown away? I don't quite understand this.
I use the following command:
ffmpeg -i 'file' -an -c:v libx264 -crf 0 'out file'