Bash Function to convert webm to mp4

.bashrc

# Based on the command used in https://askubuntu.com/a/1462885 
#
# ffmpeg -i screencast.webm -filter:v "scale=trunc(iw/2)*2:trunc(ih/2)*2,fps=30" screencast.mp4
#
# Easily call this lengthy command with webm2mp4 filename.webm
#
# Add this to your ~/.bashrc file to easily access

#function to convert webm to mp4 via ffmpeg
function webm2mp4() {
    filename="${1%.*}"
    outputname="$filename.mp4"
    if test -f "$1"; then
        printf "You chose the file: $1 \nWe'll use the name '$filename' to save it to $outputname in a moment.\n"
        if test -f $outputname; then
            while true; do
                read -r -p "$outputname exists, would you like to overwrite? (Y/N): " answer
                case $answer in
                    [Yy]* ) ffmpeg -i "$1" -filter:v "scale=trunc(iw/2)*2:trunc(ih/2)*2,fps=30" "$filename".mp4; break;;
                    [Nn]* ) printf "Not Overwriting. Please rename your file, if necessary. Exiting...\n"; return;;
                    * ) echo "Please answer Y or N.";;
                esac
            done
        elif ! test -f "$outputname"; then
            printf "$outputname does not exist, nothing to worry about overwriting -- rendering now via ffmpeg.\n"
            ffmpeg -i "$1" -filter:v "scale=trunc(iw/2)*2:trunc(ih/2)*2,fps=30" "$filename".mp4;
        fi
    elif ! test -f "$1"; then
        printf "The file does not exist.\n"
    fi
}