#!/bin/bash
# Description:
# Grab screenshot of a specified X-window and wait X-seconds

# Use xwininfo to find the Window id to the window you are going to
# grab screenshots from.
xwininfo="0x4c0001a"

# filename for output
outfile="outfile-"

# seconds sleep between grabs
sleeping=2

padding="000" # put as many padding zeros as you want on filename
for ((i=0; i<1000; i+=1))
do
        # Perform the actual screenshot grab
        xwd -id $xwininfo -out $outfile-${padding:${#i}}$i.xwd

        # Convert the xwd file to a better image format like PNG
        convert $outfile-${padding:${#i}}$i.xwd $outfile-${padding:${#i}}$i.png

        # Delete the converted XWD-file
        rm -f $outfile-${padding:${#i}}$i.xwd

        # wait
        sleep $sleeping
done

Stop the script after you have grabbed enough screenshots.

I ended up with several files named outfile-000.png outfile-001.png ...
Deleted those files that were not needed and sent the images a documentation of the booting process.

# convert thePDFfile.pdf page-%03d.png
# ls page*
page-000.png  page-001.png  page-002.png

Imagemagick can also be used to create Adobe Acrobat PDF documents

convert DSC* resultFile.pdf

The resultfile contains one image per page.

#!/bin/bash

# Description:
# Script to resize JPG images to desired width defined in IMAGESIZE variable.
# EXIF tags is also removed from the result images.
# Software needed:
# jhead - http://www.sentex.net/~mwandel/jhead/
# imagemagick - http://www.imagemagick.org

IMAGESIZE="320 480"
for IMAGEFILE in $(ls|grep JPG)
do
        for I in $IMAGESIZE
        do
                # create directories if needed
                if [ ! -d $I ]
                then
                        mkdir $I
                fi

                # Strip EXIF tag information from source file
                jhead -purejpg $IMAGEFILE

                # Resize file
                base=`basename $IMAGEFILE .JPG`_Resized_$I.JPG
                convert $IMAGEFILE -resize $I $base

                # Watermark the file
                width=`identify -format %w $base`
                convert -background '#0008' -fill white -gravity center -size ${width}x15 \
                -font Verdana -pointsize 10 \
                caption:"Copyright © 2007 Pario.no" \
                +size $base +swap -gravity south -composite $I/$base;

                # delete resized file
                rm $base
        done

        # Delete source file (DO NOT USE YOUR ORIGINAL FILE!)
        rm $IMAGEFILE
done

You can download my resize, watermark bash script here.

The following linux tools are used in the script: convert and montage, bash, od and awk. od is part of the textutils package in Debian.

#!/bin/bash
# current directory contains source JPG files
# $DESTINATION is where the prepared JPG files are stored
# $TEMP is a temporary directory
TEMP=TEMP
DESTINATION=DESTINATION
GEO=832x468 # geometry of target JPG files and resize value

for FILE in *.JPG
do
convert -resize 1x1 "$FILE" "$TEMP/1x1.bmp"
od -A n -j 54 -t u1 "$TEMP/1x1.bmp" | awk -v f="$FILE" -v des="$DESTINATION/" -v geo="$GEO" '
{
print "montage -geometry", geo, "-resize", geo, "-background rgb\\(" $3 \
"," $2 "," $1 "\\) \"" f "\" \"" des f "\"";
exit;
}'

done | sh -x

Source: comp.graphics.misc

• 3D rotate
• change/enhance brightness
• Superimposes a set of horizontal and/or vertical grid lines on an image
• etc…