Embed Subtitles, Transcode, Upload to YouTube

#!/bin/bash
#Filename:subtitle_zenity.sh
#Released under a GPLv3 Licence by Clockwork PC

#Requires Zenity --> sudo apt-get install zenity

# Select subtitle file
szSubtitle=$(zenity --file-selection --file-filter=*.srt)
echo $szSubtitle

# Select original video file
szOriginalVideo=$(zenity --file-selection)
# How do I filter for AVI or MP4 etc?
echo $szOriginalVideo

# Select name for final file
szFinalVideoName=$(zenity --entry --title="Video Name" --text="What do you want to call your file?")
echo $szFinalVideoName

#Create filename
szFinalVideo=~/Videos/Exported/$szFinalVideoName.avi

echo $szSubtitle $szOriginalVideo $szFinalVideo

#Mencoder to mux the subtitle file and AVI
mencoder -vf pp=en,scale=608:336 -oac pcm -ovc lavc -lavcopts keyint=25:vcodec=mpeg4:vbitrate=5331:vpass=1 -sub "$szSubtitle" -o "$szFinalVideo" "$szOriginalVideo" &&

#Convert AVI to MP4 for YouTube upload
ffmpeg -i "$szFinalVideo" -b 5331k ~/Videos/Exported/"$szFinalVideoName.mp4"

gnome-terminal -x ffmpeg -i "$szFinalVideo" -b 5331k ~/Videos/Exported/"$szFinalVideoName.mov"
gnome-terminal -x ffmpeg -i "$szFinalVideo" -b 5331k ~/Videos/Exported/"$szFinalVideoName.flv"

$szYouTube=~/Videos/Exported/"$szFinalVideoName".mp4

#Upload to YouTube
google youtube post --verbose "$szYouTube"