ppmtoilbm
Section: User Commands (1)
Updated: 23 October 1994
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NAME
ppmtoilbm - convert a portable pixmap into an IFF-ILBM, IFF-RGBN or
IFF-RGB8 file
SYNOPSIS
ppmtoilbm
[-ilbm|-rgb8|-rgbn]
[-ecs|-aga]
[-ham6|-ham8]
[-maxplanes|-mp
N]
[-fixplanes|-fp
N]
[-normal|-hamif|-hamforce|-24if|-24force||-deepif|-deepforce|-cmaponly]
[-hambits|-hamplanes
N]
[-deepbits|-deepplanes
N]
[-hires]
[-lace]
[-camg
hexval]
[-floyd|-fs]
[-nocompress]
[-cmethod
method]
[-mapfile
ppmfile]
[-sortcmap]
[-mmethod
method]
[-maskfile
pbmfile]
[-transparent
color]
[ppmfile]
DESCRIPTION
Reads a portable pixmap as input.
Produces an IFF-ILBM, IFF-RGB8 or IFF-RGBN file as output.
Supported ILBM types are:
- Normal ILBMs
-
1-16 planes, with colormap.
Amiga display mode Hold-any-modify (HAM) is supported, with 3-10 planes (including
the 2 control planes).
- Deep ILBMs
-
3-48 planes, direct RGB encoding. Usually 24 planes are used (for 8-bit RGB values).
- Colormap files
-
BMHD + CMAP chunk only, 0 planes.
OPTIONS
Options marked with (*) can be prefixed with a "no",
e.g. '-nohamif'. Most options can only be used for IFF-ILBM files,
if an option is usable with IFF-RGBN and IFF-RGB8 it is noted in the
description.
All options can be abbreviated to their shortest unique prefix.
- -ilbm | -rgb8 | -rgbn
-
Write an IFF-ILBM, IFF-RGB8 or IFF-RGBN file. The default is IFF-ILBM.
- -maxplanes N
-
Maximum planes to write in a normal ILBM. If the pixmap does not fit into
N
planes,
writes a HAM file (if
-hamif
is used), 24bit file (if
-24if
is used) or aborts with an error.
The default value is 5 planes (for backwards compatibility), minimum value
is 1 and maximum 8. This option can be abbreviated to
-mp.
- -fixplanes N
-
If a normal ILBM is written, it will have exactly
N
planes, even if the number of colors would fit into fewer planes. This option
can be abbreviated to
-fp.
- -hamplanes N
-
Set the number of planes (including the two control planes) for a HAM picture.
The current Amiga hardware supports 6 and 8 planes, so for now you should use only
these values. The default value is 6 (for backwards compatibility), minimum value
is 3, maximum 10.
- -hambits N
-
Set the number of bits for a color component or index value in a HAM picture.
This is the same as
-hamplanesN+2
- -deepplanes N
-
Set the number of planes for a deep ILBM.
N
must be divisible by 3.
- -deepbits N
-
Set the number of bits for a color component in a deep ILBM.
This is the same as
-deepplanes3*N
- -normal
-
Turns off
-hamif, -24if, -hamforce, -24force, -deepif, -deepforce
and
-cmaponly
and sets compression type to
byterun1.
This is the default mode for IFF-ILBM files.
- -hamif (*) | -24if (*)
-
Write a HAM or 24bit file if the pixmap does not fit into the maximum number
of planes as given by the
-maxplanes
option.
- -hamforce (*) | -24force (*)
-
Write a HAM or 24bit file.
- -cmaponly
-
Write a colormap file: only BMHD and CMAP chunks, no BODY
chunk, nPlanes = 0.
- -ecs | -aga
-
Set the appropriate
-hamplanes
and
-maxplanes
values for the Amiga ECS or AGA chipset.
ECS values are used by default for backwards compatibility.
- -ham6 | -ham8
-
Write a HAM picture with 6/8 planes.
- -hires (*), -lace (*)
-
Sets the HIRES and LACE bits in the CAMG chunk and adjusts
BMHD.xAspect/BMHD.yAspect accordingly. Other bits might be set in the CAMG
chunk depending on other options.
These options can be used with IFF-RGBN and IFF-RGB8 files.
- -camg hexval
-
Write a specific value into the CAMG chunk. The hexadecimal value can be
given with or without a
0x
prefix. Other bits might be set in the CAMG chunk depending on other options.
This option can be used with IFF-RGBN and IFF-RGB8 files.
- -nocompress
-
Do not compress the BODY chunk.
Compression requires building the ILBM image in memory; turning
compression off allows stream-writing of the image, but the resulting file
will usually be 30% to 50% larger. This options affect only IFF-ILBM files,
IFF-RGBN and IFF-RGB8 files are always compressed using a pixel repeat count.
- -cmethod method
-
Select compression method. Default is
byterun1.
Setting
method
to
none
is equivalent to using a
-nocompress
option.
method
can be abbreviated to the shortest unique prefix.
- -mapfile ppmfile
-
Use the colors in
ppmfile
as the colormap when writing a normal ILBM.
The mapfile is a normal PPM image, it can be any shape, all that matters are the
colors in it, and the order they appear in.
If the colors in the input file do not match those in
ppmfile
, they are matched to a "best match".
- -sortcmap
-
Sort the colormap.
- -mmethod method
-
Select masking method.
method
can be
none
(no masking, default),
maskplane
and
transparentcolor
(only for normal ILBMs).
lasso
masks are are not supported yet.
method
can be abbreviated to the shortest unique prefix.
- -maskfile pbmfile
-
Use a mask file to mark transparent pixels in an IFF-ILBM. If the
-mmethod
option is not used, masking method is set to
maskplane.
pbmfile
is a normal PBM image, the same size (or larger) as the input file.
A pixel value of PBM_WHITE in the mask file means the corresponding
in the input file is considered to be transparent, PBM_BLACK indicates an
opaque pixel (think of the input file casting a shadow on a white screen).
In an IFF-RGBN or IFF-RGB8 file, the mask file is used to set the
genlock bits.
- -transparent color
-
Mark the given color as transparent. The color is specified as in
ppmmake(1).
If the
-mmethod
options is not used, masking method is set to
transparentcolor.
- -floyd (*) | -fs (*)
-
Use Floyd-Steinberg error diffusion for mapping the input colors to HAM or
to the colors in a mapfile. The results are usually much better than without
it, but it takes substantially more CPU time, so the default is off.
BUGS
HAM pictures will always get a grayscale colormap; a real color selection
algorithm might give better results. On the other hand, this allows
row-by-row operation on HAM images, and all HAM images of the same depth (no.
of planes) share a common colormap, which is useful for building HAM
animations.
Not all IFF-ILBM types that are supported by
can be generated with
The number of options for this program is approaching the ls(1)-dangerlevel.
REFERENCES
Amiga ROM Kernel Reference Manual - Devices (3rd Ed.), Addison Wesley,
ISBN 0-201-56775-X, Appendix A: Interchange File Format
SEE ALSO
ppm(5), ilbmtoppm(1)
AUTHORS
Copyright (C) 1989 by Jef Poskanzer.
Modified 1993/1994 by Ingo Wilken (Ingo.Wilken@informatik.uni-oldenburg.de)
Index
- NAME
-
- SYNOPSIS
-
- DESCRIPTION
-
- OPTIONS
-
- BUGS
-
- REFERENCES
-
- SEE ALSO
-
- AUTHORS
-
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