Add an invert option to the image_seq script

image_seq.sh

@@ -1,15 +1,24 @@
 #!/bin/bash
 
+MULTIPLE=2
+RATE=`echo "scale=0;24/${MULTIPLE}" | bc`
+
 INPUT="${1}"
 OUTPUT="${2}"
+INVERT="${3}"
 
 WIDTH=323
 HEIGHT=242
 
+if [[ "${INVERT}" != "" ]]; then
+	INVERT="-vf negate"
+fi
+
 mkdir -p "${OUTPUT}"
 
 ffmpeg 	-re -i "${INPUT}" \
 	-f image2 \
-	-r 12 \
+	-r ${RATE} \
+	"${INVERT}" \
 	-vf crop=in_h/3*4:in_h,scale=$WIDTH:$HEIGHT,setsar=1:1 \
 	"${OUTPUT}/image_%06d.png"