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1995-03-09
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ppm2AGA 1.4 by Günther Röhrich
******************************
ATTENTION: At the end of this file you will find my correct EMAIL-address.
(The address from the 1.0 - release is wrong)
ppm2AGA ist a program for converting the ppm, pgm and pbm picture format into
the IFF-ILBM format. For owners of an AGA-Amiga it is now possible to create
high quality pictures without having to pay much money for a commercial image
processing software. Together with the NETPBM-package it is possible to convert
every other picture format and to do some basic image processing.
The advantages of ppm2AGA:
- very high quality in the HAM8-mode
(better than some commercial programs)
- processing pictures that are larger than the available memory is possible
- saving to the Clipboard is possible
- colormaps with full 24 Bit color precision are supported
- the source is available
- runs on all Amiga's (even with KS 1.2/1.3 if iffparse.library V37 is
available)
This program is Freeware with the following restrictions:
Some parts of the program are taken from the NETPBM-package and are therefore
Copyright (C) 1989, 1991 by Jef Poskanzer. These parts are heavily modified.
This is allowed by the original author as you can read in the following text
written by him:
Permission to use, copy, modify, and distribute this software and its
documentation for any purpose and without fee is hereby granted, provided
that the above copyright notice appear in all copies and that both that
copyright notice and this permission notice appear in supporting
documentation. This software is provided "as is" without express or
implied warranty.
If you modify or redistribute ppm2AGA you have to take care of this
permission notice. The files in the directory "Developer" are written
completely by me and they are therefore not covered by the copyright notice.
You can do what you want with them.
I have to thank the following persons:
Jef Poskanzer (jef@well.sf.ca.us):
for the development of the ppm-format and the pbm-software
Ingo Wilken (Ingo.Wilken@informatik.uni-oldenburg.de):
for the Amiga-specific parts of NETPBM and for ppmtoilbm.c
Johan Widen (jw@jwdata.se):
for the chunky->planar conversion routine in ppmtoilbm.c
Paul Heckbert:
the color quantizing routine in ppmquant.c is based on his article in
"SIGGRAPH '82 Proceedings", p. 297
The Independent JPEG Group (jpeg-info@uunet.uu.net):
for the source for decoding/encoding the JPEG-format
***********************************************************************
I have created two versions of the program:
ppm2AGA.000 for 68000 and 68010 processors, it runs on all others too
ppm2AGA.020 for 68020 or higher processors
I don't know if the 68000-version works because I don't have a 68000-based
Amiga to test it. As operating system you will need OS 1.3 or higher.
(With OS 1.3 you will need iffparse.library V37 which is available on the
Workbench 2.0 disk.)
NOTE: Newer versions of ixemul.library (40.xx) don't work any more with
Kickstart 1.2/1.3.
Invoking ppm2AGA:
ppm2AGA inputfile outputfile options
inputfile
*********
The name of the file that should be read. Supported picture formats are:
PPM - color, 24 bit/pixel (16Meg colors)
PGM - greyscale, 8 bit/pixel (256 greyscales)
PBM - black/white, 1 bit/pixel
Both binary and ASCII formats are accepted. More informations can be found
in the NETPBM-package.
outputfile
**********
This is the name of the IFF-ILBM file that should be created. If you use -cn
as a name then the file will be written to the Clipboard with unit number n.
(You should normally use unit number 0.)
options
*******
All options are case-insensitive. If they are not set then internal default
values will be used.
-HAM8 (default)
Use the HAM8 conversion method. This allows a total of 262144 different colors
for the created picture.
-HAM6
Use HAM6-mode. The quality is not very good (compared to other programs). The
created picture may have max. 4096 colors.
mode.
-CMAPn
Use the colormap conversion method with n bitplanes. (max. 8) The created
pictures will have max. 2^n colors out of about 16 millions.
If you display the picture on an ECS/OCS machine with the original hardware
then the picture will not show the original colors because these machines only
support a color selection out of 4096 colors.
You can use the -FS option with this mode.
-E
(Only for use in combination with the -CMAPn option.)
Use this option when you know that the ppm-file has a limited number of colors.
(less than 10000) This is for example the case when the ppm-file results from
a colormapped picture format like GIF, BMP, etc.
This option ensures that the original colors will be preserved. When converting
the pgm-format this option will be set automatically because pgm-files have max.
256 greyscales.
-FS
Use Floyd-Steinberg dithering. This may enhance the picture qualitiy.
When used with the HAM8-mode the enhancement will not be that much.
-Mx
Load pictures up to size x (in bytes) into memory. (default: 1000000)
-2
Use two-pass processing in the HAM6/HAM8 mode. This gives slightly better
results. With digitized pictures you will not see any difference in most
cases.
(Version 1.0 of ppm2AGA always used two passes.)
-D
Display the picture during processing. You need OS 3.0 or higher. If the
screen cannot be opened processing will continue without display. To move
the screen around with the mouse you have to activate it first. It also
has a hidden drag bar and depth gadget.
-VGA
The picture will always use the VGA screenmode (also called 'multiscan').
If your machine does not support this mode you will have problems showing
the picture. Use this option when you know that the picture was intended for
displaying on a PC or other machines with quadratic screen resolution.
NOTE: With 'quadratic' I don't mean that the screen has the same number of
pixels in horizontal and vertical direction. (e.g. 1024x1024)
I mean that a square composed of e.g. 100x100 pixels will be shown as a
square on the screen. Because a usual picture tube has a ratio of 4 to 3
the screen's resolution must be a multiple of that. (e.g. 640x480 because
640 4
--- = - )
480 3
-SMR
(New for version 1.4)
When setting this option you can use a screen mode requester to choose the
display mode. But you can choose only display modes that are available on your
machine. You will also need Workbench 2.1 or higher.
The options -HAM8, -HAM6, -CMAPx and -VGA will be ignored if they are set.
-jpegAGA
Instead of an IFF-ILBM file a map-file for the program jpegAGA will be created.
Normally, map-files are created by using a shell script. See the documentation
to jpegAGA for more.
New for version 1.4:
If it is not possible to store the map-file in the specified place (for example
if the storage media is full or write protected) then the map-file will be
stored into the directory pointed to by the MAPDIR environment variable.
jpegAGA 1.1 or higher will also search the map-file in that place.
If you don't know what options to use to get the best quality make three
conversions with the options: -HAM8 -FS, -CMAP8, -CMAP8 -FS and compare the
results.
There is also a JPEG decompression program included. It converts JPEG
pictures to the ppm format. To use it enter:
djpeg inputfile outputfile
In some cases djpeg will try to store temporary files to JPEGTMP:, you
have then to assign this directory to somewhere on your hard disk.
(for example assign JPEGTMP: HD:T)
For more informations read the included documentation.
How the program works
*********************
Not translated into English yet. Read the German documentation.
Questions and answers
*********************
Not translated into English yet. Read the German documentation. (:-)
History
*******
1.0 - 19-Apr-1994
- first public release
1.1 - 5-May-1994
- added -2 option
- one-pass processing is now the default in HAM6/HAM8 mode
(use the -2 option to get the same results as version 1.0)
- added -D option to display the picture during processing
- the documentation now contains my correct EMAIL-address
1.2 - 15-May-1994
- autoscroll bug fixed (forgot to set the SA_Overscan Tagitem)
- added -VGA option
1.3 - 4-June-1994
- added -jpegAGA option for creating map-files for the program jpegAGA
1.4 - 6-October-1994
- added support for the MAPDIR environment variable to be conformant with
jpegAGA 1.1 or higher
- you can now use Floyd-Steinberg dithering in the HAM8-mode
- added -SMR option to let you choose the screenmode much better
Announcement
************
The actual version of this program does not offer very much. My spare time
is very limited because I am now studying Electrical Engineering at the Uni-
versity Stuttgart. Therefore I am searching for other developers to cooperate
with me and beta-testers for testing purposes. If you want to join in then
please contact me. I will then create a detailed description of the source.
To recompile the source you need the newiff package from Commodore.
V37 is available on Fish-disk 705 and V39 on the "3.1 Amiga Developer Update"
disks. (Or on Aminet and on the Fresh Fish CD-ROM's.)
If you find a bug, a Mungwall/Enforcer hit, or if you have some suggestions
for additional features then send me a message.
Future plans:
- PhotoCD viewer/converter with the picture quality of jpegAGA/ppm2AGA
(This will probably done next because I have now a CD-ROM drive but no
PhotoCD viewer and I don't intend to buy one.)
This will be a free program too and I will also release the complete source.
If you are interested in such a program it would be very nice if you would
lend me some PhotoCD's for testing purposes. You will get them back together
with my viewer/converter as soon as it will be working. If you give them
to me as a present I will be even more happy. Your name will then be
mentioned in the documentation and I will also send you the program.
- graphical user interface
- support for animations, especially converting MPEG to IFF-ANIM in HAM8 mode
(This will be done next if I got the time.)
- support for other picture formats and basic image processing
(scaling, clipping, etc.)
- ARexx-port
- documentation in TeX-DVI and AmigaGuide format
- complete (and correct) translation of the German documentation
- fast ppm-viewer using the HAM8-mode with fixed colormap and doubled horizontal
resolution for higher quality, perhaps as datatype
(If you don't understand what I mean then send me a note)
- using the colormap from other pictures instead of computing it
- etc.
All messages/gifts/PhotoCD's should be sent to the following addresses:
electronic mail: normal mail:
**************** ************
Guenther@studbox.uni-stuttgart.de Günther Röhrich
(Internet EMAIL) Lerchenbergstr. 4
73733 Esslingen
Germany
NOTE: The EMAIL address from version 1.0 was wrong.
If you don't get an answer to a EMAIL within 3 weeks then try it again
with normal mail.
Here is how to get all the stuff I mentioned in the doc:
********************************************************
The NETPBM-package and the JPEG-source are available via FTP.
(for example from ftp.uni-stuttgart.de)
NETPBM: ftp.uni-stuttgart.de in pub/systems/amiga/aminet/gfx/pbm
(or on all the other Aminet mirrors)
ftp.uni-oldenburg.de in ?
JPEG: ftp.uu.net in graphics/jpeg
If you have no other possibility you can get everything directly from me.
In the document "Info.Developer" you can read how to get other developer
material, especially the "3.1 Amiga Developer Update".
NOTE: Commodore does not exist any more, I don't know if it is still possible
to get developer materials. Try to contact the German company Hirsch & Wolf oHG.