Resizing Movies with ffmpeg

Scaling down Full HD from 1920x1080 to 960x540:

ffmpeg -i input.mp4 -s 960x540 -c:a copy output.mp4

-i ... input
-s ... scale
-c ... codec

Compressing with H.2645

ffmpeg -i input.mp4 -vcodec libx265 -crf 28 output.mp4

crf ... video quality, lower value means better quality

Concatenating videos with the Quicktime Player requires unnecessary decoding/encoding, with takes time and computational resources.

Solution: Concatente Files von FFMPEG

https://trac.ffmpeg.org/wiki/Concatenate

Using ffmpeg

1. Create a list: mylist.txt

   file '/path/to/file1.mp4'
   file '/path/to/file2.mp4'
   file '/path/to/file3.mp4'

2. Run ffmpeg ffmpeg -f concat -i mylist.txt -c copy output.mp4

Troubleshooting

[concat @ 0x7fc407904080] Unsafe file name '2008-08-05 21_38_08.mov' mylist.txt: Operation not permitted

Filenames should not have spaces, escape them with \.