Image Processing

A 3d Stereogram

A 3d Stereogram: Parallel viewing method (a.k.a. the Divergence or Magic Eye method

Sample Output Output in PDF

Printing PDF with CUPS on a 3x5 inch recipe card.

lp -o media=Custom.3x5in cairojustify.pdf

Useful to eliminate dependencies on external resources.

exif: Extract Thumbnails from Digital Photos

Extract the thumbnail image from an HP digital photo.

[FreeBSD] / ports / graphics / exif

Most digital cameras produce EXIF files, which are JPEG files with extra tags that contain information about the image. The EXIF library allows you to parse an EXIF file and read the data from those tags.

http://sourceforge.net/projects/libexif/

Using Cairo Graphics Library for Dynamic Web Graphics

Here is an example of a CGI web application that dynamically creates a PNG graphic image and displays it in a web browser without creating an intermediate file.

Download cairohello.c 'C' source code

To compile

gcc cairohello.c -L /usr/local/lib -lcairo

libgd - Boutelle Graphics - gcc command line

Command line for compiling a C program that uses the GD graphics library.

The GD library creates PNG, JPEG and GIF images, among other formats. GD is commonly used to generate charts, graphics, thumbnails, and most anything else, on the fly. While not restricted to use on the web, the most common applications of GD involve web site development.

LIBGD: the GD library