Ilbmtoppm User Manual

# ilbmtoppm

Updated: 04 October 1993
Table Of Contents

## NAME

ilbmtoppm - convert an ILBM file into a PPM image

## SYNOPSIS

ilbmtoppm [-ignore<chunkID>] [ -isham | -isnotham | -isehb | -isnotehb | -isdeep | -isnotdeep ] [-cmaponly] [-adjustcolors] [-transparent color] [-maskfile filename [-verbose] [ILBMfile]

## DESCRIPTION

This program is part of Netpbm.

ilbmtoppm reads an IFF ILBM file as input and produces a PPM image as output. ilbmtoppm can handle the following ILBM types:

- Normal ILBMs with 1-16 planes.
- Amiga Extra_Halfbrite (EHB)
- Amiga HAM with 3-16 planes.
- 24 bit.
- Multiplatte (normal or HAM) pictures.
- Color map (BMHD + CMAP chunk only, nPlanes = 0).
- Unofficial direct color. 1-16 planes for each color component.

ilbmtoppm uses these ILBM chunks: BMHD, CMAP, CAMG (only HAM & EHB flags used), PCHG, BODY unofficial DCOL chunk to identify direct color ILBM. It ignores these chunks: GRAB, DEST, SPRT, CRNG, CCRT, CLUT, DPPV, DRNG, EPSF. It ignores, but displays in verbose mode, these: NAME, AUTH, (c), ANNO, DPI. It skips chunks whose type it doesn't recognize.

## OPTIONS

-verbose
  Give some information about the ILBM file.
-ignore chunkID
  Skip a chunk. chunkID is the 4-letter IFF chunk identifier of the chunk to be skipped.
-isham | -isehb
  Treat the input file as a HAM or Extra_Halfbrite picture, even if these flags are not set in the CAMG chunk (or if there is no CAMG chunk).
-cmaponly
  With this option, ilbmtoppm generates a PPM of the ILBM's color map, not the image itself.

  ilbmtoppm does the same thing even without -cmaponly if the ILBM is a pure color map stream (it has a bitmap header with an nplanes value of zero or has no BODY chunk.

-adjustcolors
  If all colors in the CMAP have a value of less then 16, ilbmtoppm assumes a 4-bit colormap and gives a warning. With this option the colormap is scaled to 8 bits.

## LIMITATIONS

The multipalette PCHG BigLineChanges and Huffman decompression code is untested.

## REFERENCES

Amiga ROM Kernel Reference Manual - Devices (3rd Ed.) Addison Wesley, ISBN 0-201-56775-X

## SEE ALSO

ppmtoilbm, ppm

## AUTHORS

Copyright (C) 1989 by Jef Poskanzer.

Modified October 1993 by Ingo Wilken (Ingo.Wilken@informatik.uni-oldenburg.de)

## Table Of Contents

- SYNOPSIS
- DESCRIPTION
- OPTIONS
- LIMITATIONS
- REFERENCES
- SEE ALSO
- AUTHORS