From 41640fe33b90ec675cb86bf8179a44618ee1cfa5 Mon Sep 17 00:00:00 2001
From: "B. Watson" <yalhcru@gmail.com>
Date: Sat, 30 Mar 2019 03:41:23 -0400
Subject: initial commit

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+img2atari - Quick & dirty image converter for Atari 8-bit computers,
+            using ImageMagick.
+
+Written by B. Watson (yalhcru@gmail.com), released under the
+WTFPL. See http://www.wtfpl.net/txt/copying/ for details.
+
+Purpose:
+
+Convert images in common formats (JPEG, PNG, etc) to black & white Atari
+8-bit image files or executables, in graphics modes 8, 9, or 15.
+
+Requirements:
+
+- Linux or some other UNIX/POSIX like environment (possibly including
+  Mac OSX). You might be able to use Cygwin or MSYS on Windows, or
+  the Ubuntu emulation included in modern Windows (?).
+
+- bash. Easily installed on most Linux and similar OSes these days, if not
+  already part of the OS.
+
+- ImageMagick. At least the convert and composite commands must be found
+  in $PATH.
+
+- Some way to run Atari 8-bit executables, either an emulator or a real
+  Atari with e.g. an SIO2PC cable.
+
+Download:
+
+  wget http://urchlay.naptime.net/repos/img2atari/plain/img2atari
+  chmod +x img2atari
+
+...or:
+
+  git clone http://urchlay.naptime.net/img2atari.git
+
+Installation:
+
+Just copy the img2atari script to some place that's in your $PATH,
+or else run it from the directory you saved it to as "./img2atari".
+
+Usage:
+
+Run "img2atari --help" for full usage information.
+
+Notes:
+
+You don't actually need the loader.s or viewer.s files. These are the
+assembly sources for the object code included in img2atari, and are pretty
+much only useful for informational purposes. You can modify them, but
+there's no easy way to import your modified code into the shell script.
+
+The input file can be in any format ImageMagick can read. This includes at
+least JPEG, PNG, GIF, TIFF, BMP, XPM, EPS... for testing, you can even use
+the ImageMagick built-in images (e.g. "logo:" for the ImageMagick logo).
+For vector formats (e.g. SVG), you'll want to render it to a PNG first.
+For multi-image formats (e.g. animated GIF, PDF), you'll want to extract
+single images and convert those.
+
+Not all images will convert to something that looks OK on the
+Atari. Photographs look OK in GR.9 (though blurry due to the low
+horizontal resolution). Line art looks better in GR.8 or GR.15.
+
+You may have to tweak the image some, before converting it. Images that
+are too dark or too bright will come out with very little detail, so
+try loading the image in an image editor and altering the saturation.
+Also, the conversion to black & white is simplistic. You may get better
+results if you pre-convert to mono or greyscale.
+
+GR.8 images with dithering may show a lot of artifacting on the Atari.
+About the only thing you can do to avoid this is use the chroma/luma
+(s-video) output instead of composite video or RF.
+
+If you get errors from convert and/or composite (e.g. because the input
+file doesn't exist, or isn't recognized by ImageMagick), the output file
+will be useless and should be deleted.
+
+The 'loader' included with the -x option uses the OS to set up the
+graphics mode, so custom resolutions (wide/narrow playfield, nonstandard
+number of scanlines) are not supported.
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