I just want to add black video at the beginning of the video
I have found following commands.
ffmpeg -i s1.mp4 -f lavfi -i color=c=black -t 10 -filter_complex "[1:v][0:v]scale2ref=1*iw/1/sar:ih/1[wm][base];[base][wm]concat=2" output.mp4
How can I solve this issue?