concat two video using ffmpeg working on local but

Question

Here the code is for concat two video and adding watermark to that video but this code working perfectly in local but not in server.

The code is as follows:

$videoFileName = rand('111111', '999999').'_'.time().'.'.$request->file('video1')->getClientOriginalExtension();

$intermediateVideo1 = rand('1111111', '9999999').'_'.time().'.ts';
$intermediateVideo2 = rand('1111111', '9999999').'_'.time().'.ts';
$concatVideoFileName = rand('111111', '999999').'_'.time().'.'.$request->file('video1')->getClientOriginalExtension();

exec('ffmpeg -i '.$request->file('video1').' -c copy -bsf:v h264_mp4toannexb -f mpegts '.$intermediateVideo1);
exec('ffmpeg -i '.$request->file('video2').' -c copy -bsf:v h264_mp4toannexb -f mpegts '.$intermediateVideo2);
exec('ffmpeg -i "concat:'.$intermediateVideo1.'|'.$intermediateVideo2.'" -c copy -bsf:a aac_adtstoasc '.public_path('uploads/videos/'.$concatVideoFileName));

exec('ffmpeg -i '.public_path('uploads/videos/'.$concatVideoFileName).' -i '.storage_path("assets/image/watermark.png").' -filter_complex "overlay" '.public_path('uploads/videos/'.$videoFileName));

File::delete($intermediateVideo1);
File::delete($intermediateVideo2);
File::delete(public_path('uploads/videos/'.$concatVideoFileName));