Actually this example seems to work better:
Code:
ffmpeg -i DVD_VIDEO1.vob -qscale 7 -vcodec libxvid -s 640x360 -r 23.976 -aspect 16:9 -ab 128k -ar 48000 -async 48000 -ac 2 -acodec libmp3lame -f avi -g 300 -bf 2 blues2.avi
I did some benchmarks and more threads = less performance, this is encoding ~2000 frames of the same movie:
Code:
1
video:5617kB audio:1320kB global headers:0kB muxing overhead 2.033539%
real 0m24.604s
user 0m24.477s
sys 0m0.093s
2
video:5654kB audio:1328kB global headers:0kB muxing overhead 2.031979%
real 0m32.787s
user 0m27.553s
sys 0m9.261s
3
video:5591kB audio:1312kB global headers:0kB muxing overhead 2.032629%
real 0m42.083s
user 0m31.680s
sys 0m25.580s
4
video:5585kB audio:1310kB global headers:0kB muxing overhead 2.032150%
real 1m25.249s
user 0m51.304s
sys 1m31.498s
So using 1 thread is the fastest.
For better quality you can use the 2 pass encoding:
Code:
ffmpeg -i DVD_VIDEO1.vob -qscale 7 -vcodec libxvid -s 640x360 -r 23.976 -aspect 16:9 -ab 128k -ar 48000 -async 48000 -ac 2 -acodec libmp3lame -g 300 -bf 2 -pass 1 -an -f rawvideo -y /dev/null
ffmpeg -i DVD_VIDEO1.vob -qscale 7 -vcodec libxvid -s 640x360 -r 23.976 -aspect 16:9 -ab 128k -ar 48000 -async 48000 -ac 2 -acodec libmp3lame -f avi -g 300 -bf 2 -pass 2 blues2.avi