
IFF FORM / CHUNK DESCRIPTION
============================

Form/Chunk ID:   FORM  ACBM  (Amiga Contiguous BitMap)
                 Chunk ABIT  (Amiga BITplanes)

Date Submitted:  05/29/86
Submitted by:    Carolyn Scheppner   CBM


FORM
====

FORM ID:  ACBM  (Amiga Contiguous BitMap)

FORM Description: 

   FORM ACBM has the same format as FORM ILBM except the normal BODY
chunk (InterLeaved BitMap) is replaced by an ABIT chunk (Amiga BITplanes). 

FORM Purpose:

   To enable faster loading/saving of screens, especially from Basic,
while retaining the flexibility and portability of IFF format files.


CHUNKS
======

Chunk ID:   ABIT  (Amiga BITplanes)

Chunk Description:

   The ABIT chunk contains contiguous bitplane data.  The chunk contains
sequential data for bitplane 0 through bitplane n.

Chunk Purpose:

   To enable loading/storing of bitmaps with one DOS Read/Write per
bitplane.  Significant speed increases are realized when loading/saving
screens from Basic.


SUPPORTING SOFTWARE
===================

(Public Domain, available soon via Fish PD disk, various networks)

LoadILBM-SaveACBM (AmigaBasic)
   Loads and displays an IFF ILBM pic file (Graphicraft, DPaint, Images).
   Optionally saves the screen in ACBM format.

LoadACBM (AmigaBasic)
   Loads and display an ACBM format pic file.

SaveILBM (AmigaBasic)
   Saves a demo screen as an ILBM pic file which can be loaded into
   Graphicraft, DPaint, Images.


