ffmpeg looping image

sometimes we need to loop an image to a video in order to overlay with cnother video. therefore we can achieve this via the simple command below:

# ffmpeg -loop 1 -i img.png -c:v libx264 -t 30 -pix_fmt yuv420p out.mp4

REF: https://trac.ffmpeg.org/wiki/Create%20a%20video%20slideshow%20from%20images