View source for ANBM IFF Animated Bitmap

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Animated bitmap form (Framer, Deluxe Video)

TITLE:  Form ANBM (animated bitmap form used by Framer, Deluxe Video) 
 
(note from the author) 
  
   The format was designed for simplicity at a time when the IFF  
standard was very new and strange to us all.  It was not designed 
to be a general purpose animation format.  It was intended to be 
a private format for use by DVideo, with the hope that a more  
powerful format would emerge as the Amiga became more popular. 
  
   I hope you will publish this format so that other formats will 
not inadvertantly conflict with it. 
  
PURPOSE:  To define simple animated bitmaps for use in DeluxeVideo. 
  
   In Deluxe Video objects appear and move in the foreground 
with a picture in the background.  Objects are &quot;small&quot; bitmaps 
usually saved as brushes from DeluxePaint and pictures are large 
full screen bitmaps saved as files from DeluxePaint.   
    
   Two new chunk headers are defined: ANBM and FSQN. 
  
   An animated bitmap (ANBM) is a series of bitmaps of the same  
size and depth.  Each bitmap in the series is called a frame and 
is labeled by a character, 'a b c ...' in the order they 
appear in the file. 
  
   The frame sequence chunk (FSQN) specifies the playback 
sequence of the individual bitmaps to achieve animation.   
FSQN_CYCLE and FSQN_TOFRO specify two algorithmic sequences.  If  
neither of these bits is set, an arbitrary sequence can be used 
instead. 
  
  
    ANBM         - identifies this file as an animated bitmap 
    .FSQN        - playback sequence information 
    .LIST ILBM   - LIST allows following ILBMs to share properties 
    ..PROP ILBM  - properties follow 
    ...BMHD      - bitmap header defines common size and depth 
    ...CMAP      - colormap defines common colors 
    ..FORM ILBM  - first frame follows  
    ..BODY       - the first frame 
       .         - FORM ILBM and BODY for each remaining frame 
       . 
       . 
  
Chunk Description: 
  
   The ANBM chunk identifes this file as an animated bitmap 
  
Chunk Spec:   
    
   #define ANBM    MakeID('A','N','B','M') 
  
Disk record:   
  
   none 
  
Chunk Description: 
  
   The FSQN chunk specifies the frame playback sequence 
  
Chunk Spec: 
  
   #define FSQN    MakeID('F','S','Q','N') 
  
   /* Flags */ 
   #define FSQN_CYCLE  0x0001  /* Ignore sequence, cycle a,b,..y,z,a,b,.. */ 
   #define FSQN_TOFRO  0x0002  /* Ignore sequence, cycle a,b,..y,z,y,..a,b, */ 
   /* Disk record */ 
   typedef struct { 
       WORD numframes;      /* Number of frames in the sequence */ 
       LONG dt;             /* Nominal time between frames in jiffies */ 
       WORDBITS flags;      /* Bits modify behavior of the animation */ 
       UBYTE sequence[80];  /* string of 'a'..'z' specifying sequence */ 
       } FrameSeqn; 
  
  
Supporting Software: 
  
   DeluxeVideo by Mike Posehn and Tom Case for Electronic Arts 
  
  
Thanks, 
   Mike Posehn
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