May 26, 2018
Perl5 module to determine the size of images in several common formats
ImageSize is a library based on the image-sizing code in the wwwimagesize script, a tool that analyzes HTML files and adds HEIGHT and WIDTH tags to IMG directives. ImageSize has generalized that code to return a raw X, Y pair, and included wrappers to pre-format that output into either HTML or a set of attribute pairs suitable for the CGI.pm library by Lincoln Stein. Currently, ImageSize can size images in XPM, XBM, GIF, JPEG and PNG formats.
I did this because my WWW server generates a lot of documents on demand rather than keeping them in static files. These documents not only use directional icons and buttons, but other graphics to annotate and highlight sections of the text. Without size attributes, browsers cannot render the text of a page until the image data is loaded and the size known for layout. This library enables scripts to size their images at run-time and include that as part of the generated HTML. Or for any other utility that uses and manipulates graphics. The idea of the basic interface + wrappers is to not limit the programmer to a certain data format.