Multi-Generation Video


#1

Here is a test which some on this forum may find of interest. It studies the effects of copying a video clip over several generations. The videos were generated using this ffmpeg script (for h.265). The script was modified for other codecs.

ffmpeg  -i C0068.mp4 -y -c:v libx265  -an  gen_2.mp4

ffmpeg  -i gen_2.mp4 -y -c:v libx265  -an  gen_3.mp4

ffmpeg  -i gen_3.mp4 -y -c:v libx265  -an  gen_4.mp4

ffmpeg  -i gen_4.mp4 -y -c:v libx265  -an  gen_5.mp4

ffmpeg  -i gen_5.mp4 -y -c:v libx265  -an  gen_6.mp4

ffmpeg  -i gen_6.mp4 -y -c:v libx265  -an  gen_7.mp4

ffmpeg  -i gen_7.mp4 -y -c:v libx265  -an  gen_8.mp4

ffmpeg  -i gen_8.mp4 -y -c:v libx265  -an  gen_9.mp4

ffmpeg  -i gen_9.mp4 -y -c:v libx265  -an  gen_10.mp4

ffmpeg  -i gen_10.mp4 -y -c:v libx265  -an  gen_11.mp4

ffmpeg  -i gen_11.mp4 -y -c:v libx265  -an  gen_12.mp4

When the script is finished we have a 12th-generation video.

here is the original h.264 video from the camera:[http://www.chrisnology.info/videos/multi_gen/C0068.MP4]

Here are the 12th-generation videos for various codecs. NOTE: All of these videos play back correctly on VLC. You may have to download these files to your machine and play them locally using VLC or a similar player.

H.264

H.265

MPEG2
http://www.chrisnology.info/videos/multi_gen/mp2_gen_12.mpg

HUFFYUV
http://www.chrisnology.info/videos/multi_gen/huff_gen_12.mkv


#2

Here is an even better presentation on video compression:

https://goughlui.com/2016/11/22/video-compression-x264-crf-generational-loss-testing/