thumbstrip is a Linux commandline program that creates thumbnail strips from
a set of input images. A thumbnail strip is a single image containing small
thumbnails of all the input images in order, each thumbnail having the same
height. Optionally thumbstrip writes a mapfile describing the output.
thumbstrip is useful for generating thumbnail images for online photo
galleries.
Say you have four large images with different heights and widths:
+------+ +------------------+ +--+ +--+
| | | | | | +--+
| | | | | |
| | +------------------+ | |
+------+ | |
+--+
If you feed these to thumbstrip, it will output a thumbnail image that looks
like this:
+--+ +----------+ ++ +-----+
| | | | || | |
+--+ +----------+ ++ +-----+
The thumbnails that make up the image all have the same height in pixels (configurable), and are placed left to right with a configurable margin. The line wraps when the maximum line length is reached. The thumbnails retain the original aspect ratio of the input images, so the width of the thumbnails can vary.
Optionally, thumbstrip creates a mapfile with the names of the images and
their coordinates in the thumbnail image. Other scripts can use the data in the
mapfile to generate clickmaps and such.
thumbstrip uses the ImageMagick library to do the heavy lifting on the image
processing. thumbstrip is only concerned with properly resizing and
positioning the thumbnail images.
Run thumbstrip without arguments to get a usage summary:
-o <outfile> image file to create, default 'pnm:-'
-m <mapfile> map file to create, optional
-h <height> height of a row in pixels, default 28
-s <space> space between thumbnails in pixels, default 4
-w <width> width of a row in pixels, default 732
-v be verbose
-? print this help screen
The default values for height and width are a bit peculiar: they were chosen to fit the layout of the author's photo site. You can set your own defaults directly at the top of the code and recompile. The help message is self-updating.
The default output is a portable bitmap (PBM) image to standard output. You can create a PNG or a JPEG from it as follows:
./thumbstrip a.jpg b.jpg c.jpg | pnmtopng > strip.png
./thumbstrip a.jpg b.jpg c.jpg | cjpeg > strip.jpgYou could also specify strip.png or strip.jpg directly as the output file
with the -o option, and ImageMagick will do the right thing.
The mapfile looks something like this:
p1030763.jpg 0 0 41 28
p1030764.jpg 45 0 86 28
p1030765.jpg 90 0 131 28
p1030766.jpg 135 0 176 28
The columns are tab-separated. The first column is the filename, the second is the x offset, the third is the y offset, the fourth is the x offset plus the width of the thumbnail, and the fifth is the y offset plus the height of the thumbnail. These coordinates happened to be convenient for further processing. It's trivial to modify the code to output different values, such as the width and height of the thumbnail, or the original dimensions of the image.
This software depends on libMagickWand, which is the ImageMagick support
library. If you have ImageMagick installed, you probably have the library too.
Download the tarball from the releases page, then run the following:
tar xvf thumbnail-0.1.tar.gz # untar the package
cd thumbnail-0.1
makeThis should compile and link the code against ImageMagick, and create a
standalone binary in the current directory called thumbstrip. You can move or
install this binary wherever you want.
Thumbstrip is licensed under the GPL version 3.