NAME¶

ilbmtoppm - convert an ILBM file into a PPM image

SYNOPSIS¶

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

DESCRIPTION¶

This program is part of Netpbm(1).

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

• ILBM
• RGBN
• RGB8
• PBM

  It 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¶

In addition to the options common to all programs based on libnetpbm (most notably -quiet, see
Common Options ), ilbmtoppm recognizes the following command line options:

-transparent color

This is the color that should "show through" in places where the image is transparent.

color is like the argument of the pnm_parsecolor() library routine .

-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

Treat the input file as a HAM picture, even if The CAMG chunk does not say it is one (or if there is no CAMG chunk).

-isehb

Treat the input file as an Extra_Halfbrite picture, even if the CAMG chunk does not say it is one (or if there is no CAMG chunk).

-isdeep

Treat the input file as a deep ILBM image, if it has the right number of planes to be one. If it does not (i.e. the number of planes is not a multiple of 3), this option has no effect other than an informational message telling you it is being ignored.

If the input file is not ILBM, this option has no effect.

-maskfile filename

This names a file for ilbmtoppm to create with the image's transparency mask. The mask file is a PBM image which maps to the input image with white pixels representing transparent pixels in the image and black pixels representing opaque pixels.

If you don't specify this, or the image does not contain transparency information, ilbmtoppm does not create a mask file.

-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(1), ppm(1)

AUTHORS¶

Copyright (C) 1989 by Jef Poskanzer.

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

DOCUMENT SOURCE¶

This manual page was generated by the Netpbm tool 'makeman' from HTML source. The master documentation is at

http://netpbm.sourceforge.net/doc/ilbmtoppm.html