ILBMTOPPM(1)

✨ Ilbmtoppm User Manual ✨

okay bestie, welcome to the ilbmtoppm manual page — it's part of the General Commands Manual series, and it's lowkey one of the cutest little converters in the Netpbm family. sit down, grab a strawberry 🍓, and let's get into it 💖

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🌸 NAME 🌸

ilbmtoppm — convert an ILBM file into a PPM image

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🎀 SYNOPSIS 🎀

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

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🦋 DESCRIPTION 🦋

This program is part of Netpbm(1). no cap, it's one of those Netpbm girlies 💅

ilbmtoppm reads an IFF ILBM file as input and produces a PPM image as output. that's the whole arc. that's the plot. 🫶

Now, the types of ILBM she can handle — she's versatile, she contains multitudes:

• 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.

(yes it really says "Multiplatte" in the source, bestie — we do not fix, we do not edit, we report faithfully 👑)

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🧚 the chunks situation 🧚

ilbmtoppm uses these ILBM chunks: BMHD, CMAP, CAMG (only HAM & EHB flags used), PCHG, BODY unofficial DCOL chunk to identify direct color ILBM.

She ignores these chunks: GRAB, DEST, SPRT, CRNG, CCRT, CLUT, DPPV, DRNG, EPSF.

She ignores, but displays in verbose mode, these: NAME, AUTH, (c), ANNO, DPI. 🙈

And chunks whose type she doesn't even recognize? she just skips them. not her business, not her problem, moving on ✨

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💅 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. spill the tea, girl ☕
• -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). she said "i don't need the CAMG chunk to know what you are" 💅
• -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. glow up, bestie ✨

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😭 LIMITATIONS 😭

The multipalette PCHG BigLineChanges and Huffman decompression code is untested.

okay so like... nobody has tested this part. fr fr. proceed with the awareness that you are the test suite. 💀

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📚 REFERENCES 📚

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

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👀 SEE ALSO 👀

ppmtoilbm(1), ppm(1)

siblings! the reverse-direction queens! iykyk 💜

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👑 AUTHORS 👑

Copyright (C) 1989 by Jef Poskanzer.

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

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🎀 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

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and that's the whole page, bestie!! 💖✨🌸 this one came out of the netpbm documentation universe, dated 12 November 2014, and it's filed under Ilbmtoppm User Manual(1). slay, read responsibly, and go convert something iconic 🦋👑💅