Scale images for the fourcell process

scale_img.sh

@@ -0,0 +1,42 @@
+#!/bin/bash
+#iWidth  323 = oWidth  404
+#iHeight 242 = oHeight 374
+
+DIGITS=6
+SCALE=$(echo "scale=$DIGITS; 323/404" | bc)
+OUTER=$(echo "scale=$DIGITS; 374/404" | bc)
+RATIO=$(echo "scale=$DIGITS; 242/323" | bc)
+
+if [[ "${1}" != "" ]]; then
+	DPI=${1}
+else
+	echo "Please provide DPI as first argument"
+	exit 1
+fi
+
+if [[ "${2}" == "" ]]; then
+	echo "Please provide input image as second argument"
+	exit 2
+fi
+
+if [[ "${3}" == "" ]]; then
+	echo "Please provide output image as third argument"
+	exit 3
+fi
+
+DIM=$(identify -ping -format '%w %h' "${2}")
+WIDTH=$(echo ${DIM} | awk '{print $1}')
+HEIGHT=$(echo ${DIM} | awk '{print $2}')
+R=$(echo "scale=${DIGITS};${HEIGHT}/${WIDTH}" | bc)
+OW=$(echo "scale=${DIGITS};${DPI}*(404/96)" | bc | awk -F'.' '{print $1}')
+OH=$(echo "scale=${DIGITS};${DPI}*(374/96)" | bc | awk -F'.' '{print $1}')
+IW=$(echo "scale=${DIGITS};${OW}*${SCALE}" | bc | awk -F'.' '{print $1}')
+IH=$(echo "scale=${DIGITS};${IW}*${R}" | bc | awk -F'.' '{print $1}')
+
+TMP=$(mktemp -d)
+convert -size ${OW}x${OH} xc:#FFFFFF "${TMP}/white.png"
+convert "${2}" -resize ${IW}x${IH}  "${TMP}/resize.tif"
+composite -gravity Center "${TMP}/resize.tif" "${TMP}/white.png" "${3}"
+rm -rf "${TMP}"
+
+echo "Centered in white ${2} -> ${3}"