download here (APR 9 2010)

This archive contains XSIZEQ v2.1, a program for resizing 24-bit BMP files at the command line. More importantly, it contains TENSAI72 which does color reduction of 24-bit BMPs and attempts to optimize the output for the target hardware. Various color depths are supported, multiple palettes, and dithering (every other pixel, Floyd-Steinberg, or none at all). Partial support for scanline color changes, and automatic palette assignment (not very effective at this time). There is also a utility, KYOUJIN V1, that simulates YUV or YJK color space with chroma subsampling and dithering. FreeBASIC source and win32 binaries are included, as well as palette definitions for C64, TMS9918, NES, and Atari CTIA. Finally, there is a batch file MAKEALL.BAT which can be used to convert one reference .BMP to a series using a wide range of settings

Actually getting the images to display on other hardware is a separate matter! But, images containing 256 or fewer colors can be saved as 8-bit palettized BMPs, and the palette is also dumped to TPALETTE.TXT and TPALETTE.PAL

Examples

reference images

Virtual On

Hasegawa Kyoko

C64 multicolor Atari 5 color TMS9918

NES MSX2 MSX2+

128KB EGA

Genesis Master System

VBXE

PCE/TurboGrafx