Raven’s realm

Here is the thing: imagine you have been taking a whole bunch of photos of quite similar scene. After reviewing all of them you made a short list of, say, four the best. You wish you could narrow this list down to only ONE photo.

And, here comes a thought: let’s do a photo strip.

Of course you could start Photoshop, Gimp, or any other photo editing program you like, and start stitching them all together, adding border, etc.

What if these photos where taken with your state of the art 12M photo camera ? And you computer/laptop is quite far from being called state of the art ?

I have tried doing it once with my MacBookPro (2007). Almost burned this poor machine

Gladly I am not afraid of bash scripting and tools like ImageMagick.

Here is a simple script that does the stitching for us. My MBP managed to do the hard work in just few seconds.


#!/bin/bash

FILES=$1
DIR=$2
WIDTH=$3
HEIGHT=$4
STEP=$5

OUTPUT=$6

if [ "$FILES" = "" ];
then
echo "Need 1st parameter: FILES [\"*.tif\"]"
exit 1
fi

if [ "$DIR" = "" ];
then
echo "Need 2nd parameter: DIR [1]"
exit 1
fi

if [ "$WIDTH" = "" ];
then
echo "Need 3rd parameter: WIDTH [500]"
exit 1
fi

if [ "$HEIGHT" = "" ];
then
echo "Need 4th parameter: HEIGHT [500]"
exit 1
fi

if [ "$STEP" = "" ];
then
echo “Need 5th parameter: STEP [0.04]”
exit 1
fi

if [ "$OUTPUT" = "" ];
then
echo “Need 6th parameter: OUTPUT file”
exit 1
fi

if [ "$DIR" = "w" ];
then
DX=1
DY=0
BORDER=`echo “$STEP*$WIDTH” | bc`
else
DX=0
DY=1
BORDER=`echo “$STEP*$HEIGHT” | bc`
fi

ls $FILES | \

awk -v DX=$DX -v DY=$DY -v W=$WIDTH -v H=$HEIGHT -v BORDER=$BORDER -v STEP=$STEP -v OUTPUT="$OUTPUT" \
'BEGIN { print "convert \\"; X=0; Y=0; } \
{ print "\\(",$1,"-resize "W"x"H"^ -repage +"X"+"Y" \\) \\"; X=X+(1+STEP)*(DX*W); Y=Y+(1+STEP)*(DY*H) } \
END { print "-background black -fill black -compose Over -mosaic -bordercolor black -border "BORDER,OUTPUT; }' |\
sh -


To execute the script simply call:

./script.sh "Photo-?.tif" w 500 500 0.04 Photos-strip.tif

where parameters are:

1. Photo-?.tif – tells to process all Photo-1.tif, Photo-2.tif, … in the current folder
2. Should we create horizontal (‘h’) or vertical (‘w’) strip
3. Width of each photo in the strip
4. Height of each photo in the strip
5. Fraction of width/height for the outside and inside borders
6. Name of the output strip file

And here is the output:

Enjoy!