Why won't the video convert?

Question

Yii

Here I am uploading a video to the server with conversion to the required qualities, but for some reason the ffmpeg command does not work.
The code for the download itself.

Here is the method with the command, there must be an error somewhere.

Here is the method for obtaining the necessary permissions

. for some reason removes the tabulation

Answer 1

Redirect your command's stdout and stderr to a file and see what's wrong.