Need to add 5 seconds of black at the beginning of the video

[aristofeles]

I have a few small video files, 5.1 sound, it starts already with sound but my receiver takes a few seconds to output this audio. How can I add a few seconds on nothing - black screen with no sound - to those files?

[ProWo]

Post a mediainfo report of one of this videos here (text mode)

[Budman1]

I inputted for a 5 second blank black video into my test program and got:

ffmpeg -f lavfi -i color=Black:s=854x480:d=5:rate=29.97 -t 5 -f lavfi -i anullsrc=r=44100:cl=5.1 -c:a aac "C:\Users\Bud\Desktop\Black854 X 480_1.mp4"

Change the parameter for you choice and Just merge this to the start of your video.