GIFFilter and JPEGFilter

GIFFilter is a GIF filter service.  It converts GIF (Graphics Interchange Format) images to TIFF, allowing NeXTSTEP applications to load and display GIF images.

The guts of the conversion code was lifted from ImagePortfolio.app by Martin D. Flynn. His code is by far the fastest I've found for GIF conversion. I've basically taken his conversion code, added gamma correction, and written an image filter service around it.

A few things could be improved in my filterÐone of the major things being better error notification.

Feel free to lift from my code as well. No restrictions.

JPEGFilter is a JPEG filter service.  It converts JPEG (JFIF format) images to TIFF, allowing NeXTSTEP applications to load and display JPEG images.

The conversion code is based on the Independent JPEG Group's JPEG software (version 4) code freely available on the Internet (ftp.uu.net in graphics/jpeg). I've written an image filter service around the conversion code and added gamma correction. You'll need the header files and the jpeg library in the Independent JPEG Group's JPEG software in order to compile the JPEGFilter. I made some slight changes in the Independent JPEG Group's code to handle what appeared to be Macintosh resource forks at the beginning of JPEG's produced on the Mac. Contact me if you wish to obtain the code changes I made (I'll only provide the changed source files, please obtain the original distribution from the archives).

Michael McCulloch
michael@hsv.tybrin.com