#!/bin/bash
[ -e "$1" ] || exit 1
INFILE="$1"
BASENAME="${1%.*}"
EXT="${1##*.}"

# Get a unique output filename.
NUM=1
OUTFILE="$BASENAME-$NUM.$EXT"
while [ -e "$OUTFILE" ] ; do
	NUM=`expr $NUM + 1`
	OUTFILE="$BASENAME-$NUM.$EXT"
done

echo Adding stereo audio stream from \"$INFILE\" to \"$OUTFILE\"
/usr/local/bin/avconv-9.11 -i "$INFILE" -i "$INFILE" -map 0:a:0 -map 1 -c copy -c:a:0 aac -ac 2 -strict experimental -metadata:s:a:0 title=Stereo "$OUTFILE"
touch -r "$INFILE" "$OUTFILE"