concat两个视频使用ffmpeg工作在本地但不工作在服务器上为什么？

Question

此处的代码适用于concat两个视频并为该视频添加水印，但此代码在本地但不在服务器中完美运行。

代码如下：

$videoFileName = rand('111111', '999999').'_'.time().'.'.$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));