Zoom video using ffmpeg commands

Is it possible to zoom a video and save it using ffmpeg commands?

I searched a lot but I did not find any solution.

Answer

Zooming is a two step process. You want to:

1. Scale the video by a factor of your choice.


2. Crop the video back to its original size.

That'd look something like this, e.g. to zoom in with a factor of 2, assuming an input video of 1280×720 pixels:

ffmpeg -i input.mp4 -vf "scale=2*iw:-1, crop=iw/2:ih/2" output.mp4

Of course, you can change the factor here. The -1 means that the height will be set automatically.

You can use two additional parameters for the crop filter to set the position of the cropping window.

Have a look at the x264 encoding guide if you need to change the output quality (it will be reduced compared to the original, of course).