ltx-qoa 0.1b1

QOA sound datatype, stereo, 68000+

Short:        QOA sound datatype, stereo, 68000+
Author:       Tobias Karlsson
Uploader:     tobias karlsson piratkopia se (Tobias Karlsson)
Type:         util/dtype
Version:      0.1b1
Architecture: m68k-amigaos >= 3.0.0

================================================================
  QOA - QOA sounds for every Amiga: a datatype
================================================================


WHAT IT IS

  QOA ("Quite OK Audio", qoaformat.org) is a compressed sound
  format: a fifth of the size of plain 16-bit sound, sounding
  nearly the same, and simple enough to decode on a 68000. This
  package teaches the Amiga to play it:

  qoa.datatype  plays QOA sounds in every program that plays
                sounds through datatypes: MultiView, a double-
                click on Workbench, file managers, AmigaGuide,
                browsers

  One build for every Amiga, from a 68000 up, with OS 3.0 or
  later. About 6 KB.


FEATURES

  - Stereo on OS 3.5, 3.9 and 3.2 (sound.datatype 44 and later);
    files with more channels play their first two, front left and
    right
  - Mono on OS 3.0 and 3.1, whose sound.datatype has no stereo:
    all the channels are mixed into one

  - 44.1 and 48 kHz files play at the right speed: Paula plays at
    most about 28 kHz, so faster sound is averaged down to half (a
    third, a quarter...) while it is decoded, instead of playing
    slow

  - Fast: the per-sample loop is hand-written 68000 assembly. On
    the real A1200 (Emu68, OS 3.2) a minute of 44.1 kHz stereo
    opens in 0.8 seconds

  - Little memory: the file is read a frame (at most 16 KB) at a
    time and decoded straight into the 8-bit sound; only that is
    held, about 2.5 times the file's size in stereo, half that in
    mono

  - Save as 8SVX: MultiView's Save As writes an 8SVX with the
    right rate and length in its header

  - Safe with broken files: every frame is checked before it is
    decoded; a damaged file plays up to the damage. The same
    samples as the reference decoder (qoa.h) on 1,100 test files,
    whole and damaged

  - Recognised by its first bytes ("qoaf"), whatever the file is
    called

  Not played: "streaming" QOA files (no length in the header) and
  files with more than 8 channels.

  On a plain 68000 or 68020 the whole sound is decoded before it
  plays, which takes longer than it plays: encode at 22 kHz (see
  qoa.doc), and keep long songs for faster Amigas.


INSTALLATION

  Classes/DataTypes/qoa.datatype  to SYS:Classes/DataTypes/
  Devs/DataTypes/QOA              to DEVS:DataTypes/

  Then AddDataTypes REFRESH, or restart the Amiga. The full manual
  is qoa.doc.


SOURCE

  https://github.com/creep-ltx/AmigaDatatypes  (folder qoa, MIT)


HISTORY

  0.1b1 (17.10.2026) - the first version