PNG8 ==== This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License (Version 3) for more details. Usage: ------ png8 -- convert a file Options ------- General switches: -h - Help text. One of these switches must be provided: -1 - Produce a monochrome sprite data set (e.g. Spectrum). -4 - Produce a 4-colour sprite data set (e.g. Commodore 64). Optional switches: -b - Don't treat black the same as a transparent pixel. -p - Use in place of 'byte' for output. -s - For monochrome data, produce pre-shifted values. -w - Set the sprite width to . This must be a multiple of 8. -d - Don't use double-width pixels in 4 colour mode. -c0 - Set colour 0 to RGB value RRGGBB, expressed as a hex number. -c1 - Set colour 1 to RGB value RRGGBB, expressed as a hex number. -c2 - Set colour 2 to RGB value RRGGBB, expressed as a hex number. -c3 - Set colour 3 to RGB value RRGGBB, expressed as a hex number. Instructions ------------ PNG8 processes a sprite image strip and produces output that should be compatible with most 8-bit assemblers. For monochrome images it produces 1-bit per pixel output, where any pixel that is transparent or black (by default; this can be disabled with the -b switch) is treated as a clear bit in the generated output. Other pixels are treated as a set bit. For 4-colour images it generates bit patterns "00" for colour 0 (default black), "01" for colour 1 (default red), "10" for colour 2 (default green) and "11" for colour 3 (default blue). The colours used can be controlled by the switches -c0 to -c3. Note that in reality anything that is not colour 1, 2 or 3 is treated as colour 0. 4-colour mode assumes that pixels are double width as well (like on the C64). To disable that use the -d switch. # vim: spell