Merge audio and video FLV scripts with PHP and FFMPEG

merger.php

<?php
	$streamsPath = realpath("/usr/share/red5/webapps/vod/streams");
	
	$videoFile = "$streamsPath/356a192b7913b04c54574d18c28d46e6395428ab-1312327917237_Video.flv";
	$audioFile = "$streamsPath/356a192b7913b04c54574d18c28d46e6395428ab-1312327917237_Audio.flv";

	// convert audio FLV to mp3
	$targetAudio = dirname(realpath($audioFile))."/audio.mp3";
	system("ffmpeg -y -i $audioFile -ac 2 -ab 128kb $targetAudio");

	if(!realpath($targetAudio))
		throw new Exception("Audio conversion failed");

	$basename = basename($videoFile);
	$filename = substr($basename, 0, strrpos($basename, "_Video."));
	$targetVideo = dirname(realpath($videoFile))."/$filename.flv";

	system("ffmpeg -itsoffset 00:00:0.75 -i $videoFile -itsoffset 00:00:0 -i $targetAudio -acodec copy -vcodec copy $targetVideo");

	if(!realpath($targetVideo))
		throw new Exception("Merge process failed");
?>

I used same code in localhost, It is done well. But i upload on my shared server it is not working.....

I used same code in localhost, It is done well. But i upload on my shared server it is not working.....

You have asked this question everywhere, here's your answer.

You do not have it installed on your shared server, you need to contact the support for your shared server or upgrade to a virtual server. You cannot execute FFMPEG if it isn't installed