It seems your convert command not working

/usr/bin/mencoder '/home/srmaster/public_html/vidz/video/re3.mpg' -o /home/srmaster/public_html/vidz/flvideo/1192056732598947630.flv -of lavf -oac mp3lame -lameopts abr:br=56 -ovc lavc -lavcopts vcodec=flv:vbitrate=500:mbd=2:mv0:trell:v4mv:cbp:l ast_pred=3 -srate 22050 -ofps 24 -vf harddu
p

Check if the file "/home/srmaster/public_html/vidz/video/re3.mpg" present on your server.

You may need to try old convert command also, replace current convert command in include/settings/video_conversion.php with following and try uploading a new video.

Code:
$cmd_mencoder = "$config[mencoder] '$video_src' -o $video_flv -of lavf -oac mp3lame -lameopts abr:br=56 -ovc lavc -lavcopts vcodec=flv:vbitrate=500:mbd=2:mv0:trell:v4mv:cbp:last_pred=3 -srate 22050 -lavfopts i_certify_that_my_video_stream_does_not_use_b_frames";
If both of the command can't convert the video to FLV format (/home/srmaster/public_html/vidz/flvideo/1192056732598947630.flv) there should be a server problem. Contact support for your web host with the convert command and ask why the video is not getting converted with the command, they may able to fix the problem.