I converted an
avc (h264) file to an
hevc (h265) file and an
av1 file.
Relative to the
hevc (h265) file, the
av1 file is far larger in size, and the
av1 file has worse psnr and ssim results too.
With the
hevc (h265) file, i used the default crf setting (28)
av1 doesn't have a default crf amount, but i used the ffmpeg recommendation of 30
Here's the command i used to do the
hevc (h265) conversion
C:\Users\l\Desktop\6-app\ffmpeg -i y.mp4 -c:v libx265 -preset 8 -vf scale=1920:1080 -r 60 -ab 192k -ar 48k -map_chapters -1 -map_metadata -1 z.mp4
Here's the command i used to do the
av1 conversion
C:\Users\l\Desktop\6-app\ffmpeg -i y.mp4 -c:v libaom-av1 -crf 30 -b:v 0 -strict experimental -vf scale=1920:1080 -r 60 -ab 192k -ar 48k -map_chapters -1 -map_metadata -1 z.mkv
Here are the psnr and ssim results of the
hevc (h265) file
ssim
Y:0.981764 (17.390662)
U:0.992258 (21.111573)
V:0.992246 (21.104816)
All:0.985260 (18.315015)
psnr
y:41.620801
u:48.257839
v:47.699066
average:42.905441
min:38.873493
max:58.862531
Here are the psnr and ssim results of the
av1 file
ssim
Y:0.923286 (11.151250)
U:0.991684 (20.800862)
V:0.987425 (19.004970)
All:0.945376 (12.626126)
psnr
y:27.332443
u:44.955360
v:41.569108
average:29.034062
min:8.783696
max:59.518112
Here are the size results of the files
avc
3.9 mb
hevc (h265)
4.6 mb
av1
9.59 mb
I know i'm compressing an already well-compressed file, I didn't necessarily expect a smaller file size - but i did expect av1 to outperform hevc (h265))
Here are the actual files
https://www.dropbox.com/s/4xy7tsys5c...c-original.mp4
https://www.dropbox.com/s/fnakxv248s...mbo-3-hevc.mp4
https://www.dropbox.com/s/07x5ddc54j...ombo-3-av1.mkv
Why would such poor results occur?