[FFmpeg-user] merged video fails to play

[Carl Eugen Hoyos]

a b <microspam <at> list.ru> writes:

> $ ffmpeg -loop 1 -r 24 -i image.png -t 00:00:05 
> -vcodec h264 -pix_fmt yuv420p -an image.mp4

> Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'image.mp4':
> Duration: 00:00:03.00, start: 0.000000, bitrate: 46 kb/s
> Stream #0:0(und): Video: h264 (High 4:4:4 Predictive)

It is very unlikely that above command (that requests 4:2:0) 
was used to produce the input file (that has 4:4:4).

You can only use concat on two videos with the same (very 
similar) properties, ie you need the same pix_fmt for both 
input videos.

Carl Eugen