Convert PNG or JPEG images to ST / STE low resolution • ST / PRG / PI1
The Atari ST shows its low-resolution screen in 320×200 with 16 colours, chosen from 512 on the ST or 4096 on the STE, stored as four interleaved bitplanes. This converter finds the best 16-colour palette for your image, dithers it, and exports a classic DEGAS .PI1, a self-displaying .PRG and a bootable .ST floppy that shows the picture as soon as the machine starts. It runs entirely in your browser — your image is never uploaded.
A 720 KB double-sided floppy image with the viewer in its AUTO folder: TOS runs it at boot, the picture appears, and a key press restores the screen and carries on to the desktop.
The same viewer as a standalone TOS program (68000 code, palette and screen included): double-click it from the desktop or drop it in an AUTO folder. It switches to low resolution, shows the picture, waits for a key, then restores the resolution and colours.
The viewer reloads all 16 colour registers three times per scan line with cycle-exact 68000 code (24 move.l per line, synchronised on the video address counter), giving smooth gradients far beyond 16 colours. Downloads become .SPU (the standard Spectrum 512 file), a self-displaying .PRG and a bootable .ST. Press SPACE to leave the viewer. Keep Black border on: colour 0 is also the border colour, which would otherwise show coloured stripes.
32034 bytes: resolution word, 16 palette words, 32000-byte screen. Opens in DEGAS Elite and most ST paint and conversion tools.
The original ST picks its 16 colours from 512 (3 bits per channel); the STE, Mega STE, TT and Falcon accept 4096 (4 bits per channel), giving smoother gradients. An STE picture still runs on a plain ST, with slightly coarser colours.
Download the .ST floppy image and boot from it: the viewer in its AUTO folder starts on its own. Use Hatari, STeem or a real ST with a Gotek or HxC. Press any key to continue booting to the desktop.
A 1987 trick by Trio Engineering: the display routine rewrites the 16 colour registers three times on every scan line, so each line can show 48 colours from 512 (or 4096 on the STE). The .SPU file stores the screen plus 199 x 48 palette words; the .PRG and .ST contain a cycle-exact viewer. It needs a 50 Hz ST/STE, real or emulated (Hatari).
The DEGAS low-resolution format: a resolution word, the 16-colour palette and the 32000-byte screen, readable by DEGAS Elite, NEOchrome converters and most Atari picture tools.
No, everything runs in your browser; nothing leaves your device.
The other 16-bit classic? Try the PNG to Amiga IFF converter, go 8-bit with the PNG to Amstrad CPC converter, or browse all RetroVault tools.
Your image stays in your browser — it is never uploaded to our server
Atari 520 / 1040 ST, STE, Mega ST, Mega STE • TOS / EmuTOS • Hatari tested
