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QOI - QOI pictures for every Amiga: a datatype and a converter
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WHAT IT IS
QOI ("Quite OK Image", qoiformat.org) is a lossless picture
format with full colour and transparency that decodes many
times faster than PNG. This package teaches the Amiga to use it:
qoi.datatype shows QOI pictures in every program that opens
pictures through datatypes: MultiView, a double-
click on Workbench, file managers, paint programs
ToQOI turns pictures into QOI files: anything the Amiga
has a picture datatype for (PNG, JPEG, GIF, BMP,
WebP, ILBM...)
Both are one build for every Amiga, from a 68000 up, with
OS 3.0 or later.
FEATURES
- Full colour with transparency on OS 3.5, 3.9 and 3.2; on 3.2
the pixels go straight into picture.datatype's own buffer
- 256 colours on OS 3.0 and 3.1, whose picture.datatype takes no
full colour: a picture with 256 colours or fewer keeps exactly
its own, a bigger one gets the best 256 with dithering
- Fast: a decoder written for the 68k, with a hand-written loop
for the 68020 and later chosen at run time. On the real A1200
(Emu68) photos open 2.4-3.6x faster than with the older QOI
datatype on Aminet, and 3.5-9x faster than the same pictures as
PNG with OS 3.2's own png.datatype
- ToQOI keeps PNG transparency and the transparent colour of GIF
and ILBM pictures; on OS 3.0/3.1 it reads HAM and Extra-
Halfbrite pictures itself. Patterns, a target drawer, and a
Workbench start: select pictures, then shift-double-click ToQOI
(give it a tool icon first)
- Little memory: neither the datatype nor ToQOI ever holds the
whole file, and ToQOI never holds the whole picture
- Safe with broken files: every pixel the same as the reference
decoder's (qoi.h), also for damaged and cut-short files,
checked on 450 test pictures and fuzzed. Every byte ToQOI
writes is the same as the reference encoder's
- Recognised by its first bytes ("qoif"), whatever the file is
called
COMPARED WITH THE OLDER QOI DATATYPE (qoi-datatype 0.6, 2022)
- It needs picture.datatype 43 and does not open QOI pictures on
OS 3.0 or 3.1; this one shows them there in 256 colours
- It drops transparency (transparent parts turn black); this one
keeps it
- This one opens pictures 2.4-3.6x faster (real A1200)
- It has no converter; this package has ToQOI
INSTALLATION
Classes/DataTypes/qoi.datatype to SYS:Classes/DataTypes/
Devs/DataTypes/QOI to DEVS:DataTypes/
C/ToQOI to C:
Then AddDataTypes REFRESH, or restart the Amiga if another
qoi.datatype was installed before. The full manual is qoi.doc.
SOURCE
https://github.com/creep-ltx/AmigaDatatypes (folder qoi, MIT)
HISTORY
0.1b1 (17.10.2026) - the first version: qoi.datatype and ToQOI
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aminet net>