To convert a single image to video, use the -loop
option to specify we are looping an image & the -t
option to specify the duration of the resulting video:
-loop 1 -i <img_in> -t <duration>
To add empty audio, use the lavfi
format with anullsrc
input (change channel layout & sample rate as needed):
-f lavfi -i anullsrc=channel_layout=mono:sample_rate=44100
Example:
ffmpeg -loop 1 -i <img_in> -f lavfi -i anullsrc=channel_layout=mono:sample_rate=44100 \
-r 30 -c:v libx264 -c:a aac -t 8 <vid_out>