Fred's ImageMagick Scripts



    Licensing:

    My scripts are available free of charge for non-commercial use.

    If you redistribute or incorporate any of these scripts into other free applications, you may use my scripts by simply referencing my name and this web page: Fred Weinhaus and http://www.fmwconcepts.com/imagemagick/index.html

    For use of my scripts in commercial use or non-free applications, please contact me for licensing arrangements.
    My email address is fmw at alink dot net.

    Usage, whether stated in script or not, is also subject to the ImageMagick license, which can be found at: http://www.imagemagick.org/script/license.php

TILER


Converts an image into a tilable texture.

Download Script

last modified: November 28, 2011



USAGE: tiler [-m method] [-o overlap] [-v vpmethod] infile outfile
USAGE: tiler [-h or -help]

-m .... method ...... method of overlap blending; choices are 1 or 2;
..................... 1 is simple average blending; 2 is ramped blending;
..................... default=1
-o .... overlap ..... seam overlap amount in pixels; integer>=0; default=2
-v .... vpmethod .... virtual-pixel method used to extend the quadrants;
..................... any valid IM non-background virtual-pixel method
..................... is allowed. Best choices seem to be mirror or edge;
..................... default=mirror

NOTE: the input image (infile) must be square and have even dimensions.

PURPOSE: To convert an image into a tilable texture.

DESCRIPTION: TILER converts an image into a tilable texture. It does this by swapping diagonal quadrants, exending the borders to get overlap and then composite blending the extended quadrants. The extension and blending attempt to minimize or avoid manual painting/blurring/cloning along the seams.

ARGUMENTS:

-m method ... METHOD of overlap blending. The choices are 1 or 2. Method 1 is a simple average blending. Method 2 is a ramped blending. The default=1.

-o overlap ... OVERLAP is amount of extension of the quadrants in order to cover the center horizontal and vertical seems. Values are integers>=0. The default=2

-v vpmethod ... VPMETHOD is the virtual-pixel method used to extend the quadrants. Any valid IM non-background virtual-pixel method is allowed. Recommended values are either mirror or edge. The default is mirror.

Requirement: IM 6.5.3-4 or higher due to the use in method 1 of convert ... -compose blend -define compose:args=50,50 -composite ...

CAVEAT: No guarantee that this script will work on all platforms, nor that trapping of inconsistent parameters is complete and foolproof. Use At Your Own Risk.


EXAMPLES


Example: Rocks

Original Image

Quadrant Swap Only:
convert rocks256.jpg -roll +128+128 rocks256roll.jpg

Arguments:
-m 1 -o 2 -v mirror

2x2 Tiling
convert -size 512x512 tile:rocks256_tile_mirror.jpg rocks256_tiled512.jpg



Example: Dirt

Original Image

Quadrant Swap Only:
convert dirt256.jpg -roll +128+128 dirt256_roll.jpg

Arguments:
-m 1 -o 2 -v mirror

2x2 Tiling
convert -size 512x512 tile:dirt256_tile_mirror.jpg dirt256_tiled512.jpg



Example: Random

Original Image

Quadrant Swap Only:
convert random256.jpg -roll +128+128 random256roll.jpg

Arguments:
-m 1 -o 2 -v mirror

2x2 Tiling
convert -size 512x512 tile:random256_tile_mirror.jpg random256_tiled512.jpg



What the script does is as follows:

  • Crops each quadrant of the original image and unfolds the relevant edges
  • Rolls the original image half way
  • Does a blend composite of each successive quadrant over the rolled image

This is equivalent to the following IM commands for method 1

  • wd=`convert $infile -ping -format "%w" info:`
  • ht=`convert $infile -ping -format "%h" info:`
  • ww=`convert xc: -format "%[fx:$wd/2]" info:`
  • hh=`convert xc: -format "%[fx:$ht/2]" info:`
  • wwo=`convert xc: -format "%[fx:$ww+$overlap]" info:`
  • hho=`convert xc: -format "%[fx:$hh+$overlap]" info:`
  • rollamount="+${ww}+${hh}"
  • cropsize="${ww}x${hh}+0+0"
  • www=$(($ww+$overlap))
  • hhh=$(($hh+$overlap))
  • sesize="${www}x${hhh}+0+0"
  • swsize="${www}x${hhh}-$overlap+0"
  • nesize="${www}x${hhh}+0-$overlap"
  • nwsize="${www}x${hhh}-$overlap-$overlap"
  • gsize=$(($overlap + 2))
  • convert $infile \
    \( -clone 0 -gravity southeast -crop $cropsize +repage -virtual-pixel $vp \
    -define distort:viewport=$sesize -distort SRT 0 +repage \) \
    \( -clone 0 -gravity southwest -crop $cropsize +repage -virtual-pixel $vp \
    -define distort:viewport=$swsize -distort SRT 0 +repage \) \
    \( -clone 0 -gravity northeast -crop $cropsize +repage -virtual-pixel $vp \
    -define distort:viewport=$nesize -distort SRT 0 +repage \) \
    \( -clone 0 -gravity northwest -crop $cropsize +repage -virtual-pixel $vp \
    -define distort:viewport=$nwsize -distort SRT 0 +repage \) \
    \( -clone 0 -roll $rollamount \
    -clone 1 -gravity northwest -compose blend -define compose:args=50,50 -composite \
    -clone 2 -gravity northeast -compose blend -define compose:args=50,50 -composite \
    -clone 3 -gravity southwest -compose blend -define compose:args=50,50 -composite \
    -clone 4 -gravity southeast -compose blend -define compose:args=50,50 -composite \) \
    -delete 0-4 \
    $outfile