PNG-gio

Short:        PNG gio (beta) for Photogenics 1.2
Author:       Jolyon @ Almathera
Uploader:     thp cix compulink co uk
Type:         gfx/show
Architecture: m68k-amigaos

PNG.gio V0.9 BETA!
==================

Jolyon Ralph, Almathera Systems Ltd - 14th June 1995.


PNG (Portable Network Graphics) is a new image format, designed to
replace GIF as a worldwide image standard for image files.

PNG.gio is an add-in for Photogenics 1.2 to support loading and
saving these files.

Currently PNG.gio should load all PNG images, but is limited to
saving non-interlaced PNG images (unless you know what interlaced PNG
images are for this should not be a big problem).

PNG.gio can save 24-bit, 8-bit, 4-bit and 1-bit images.  Palettes are
calculated and the image dithered automatically for non-24-bit
images.

PNG.gio will *NOT* work with Photogenics 1.0, 1.1 or 1.1a.  You must
upgrade to V1.2 of Photogenics.

If you have an earlier version of Photogenics, then you can order the
upgrade for 1.2:


email: almathera@cix.compulink.co.uk   (ordering information)


If you have any problems/find bugs in this .gio, please send email
to:

jralph@cix.compulink.co.uk (technical enquiries only)


PNG.gio was written by Jolyon Ralph.  It is Copyright (C) Almathera
1995.  All Rights Reserved.

It may be freely distributed by any means as a service to registered
Photogenics 1.2 users only.  Aminet have explicit permission to
distribute this both electronically and via CD-ROM.

PNG.gio is based on the pnglib library code written by, and Copyright
(C) 1995 Guy Eric Schalnat, Group 42, Inc.


Note:  We have also included a new version of PCD.gio in this
archive.  This is a small maintenance upgrade to PCD.gio which fixes
a minor problem with autodetecting small image files (PCD.gio was
preventing some other .gio files from working correctly).


--------------------------------------------------------

To install:

Copy the PNG.gio file into the Photogenics:data/gio/ directory.  Copy
the PCD.gio file into the same directory, overwriting your original
PCD.gio file.

Restart Photogenics, and PNG should be available in both the Loaders
and Savers windows.  Use it like any other file GIO.

----------------------------------------------------------

History:

V0.9beta:  first public release.  Support for loading PNG files
(should load everything) and saving 24-bit, 8-bit, 4-bit and 1-bit.

Not done yet:  Support for saving greyscale/monochrome images,
support for interlaced images.