===============================================================================
                         Megumi - Cute Image Viewer
                         1997,1998   Dirk Krumbholz
                                Version 2.00
===============================================================================

Introduction
------------
Megumi is a fast and cute image viewer for RiscOS 3.5 or higher. She was
especially designed to handle graphic formats often used to encode Anime
pictures. She is also capable of displaying animated image formats.

For maximum speed, the image decompression routines were implemented in
hand-written ARMcode. The whole decoding is multitasking and Megumi uses
fade-in effects to support interlaced formats .


Quickstart
----------
Megumi looks best in high or true color screen modes. Of course all the normal
things will work, i.e. to load a picture simply double click it or drag it to
the icon bar...

Data or DOS files can be identified on the fly. Megumi will filetype them, if
this option is enabled. On the other hand correctly typed files will be
checked for valid header information. If this check fails, the file will be
detyped i.e. it becomes a data file.

While she is decoding a picture, you can do whatever you like, except loading
another picture (there's no multithreading). Closing the window will abort the
loading process.

The zoombox lets you to zoom in and out, the info window provides information
about both the source and the created sprite. Megumi will fill in the fields
during the decoding process.

After the decoding is finished, you can save the created sprite. If Megumi
founds more than one image in the file, she will display an animated sequence.
ECC Animations are handled somewhat different.

You can load the next picture with a select click, or the previous picture
with an adjust click. These are relative to the directory where the loaded
picture is located.

Well, that's all.



The Info Window
---------------
Note: You can make the info window permanent by clicking on the info item
      instead of following the sub-menu pointer.

The fields in detail:
Name	- The filename
Type    - The type of the source, e.g. GIF
Frames  - The number of images found in the file.
          If there's only one, this box will stay empty.
	  'Running' means the animation is done on the fly to save memory.
	  'Stopped' means a running animation has ended, maybe normally.
Bytes   - The size of the source
BPP	- The color resolution of the source
Width   - The x-resolution of the image
Height  - The y-resolution ot the image
Bytes   - This time it's the size of the created sprite. It shows you how much
	  disc space is needed, if you wish to save it.
BPP	- The color resolution of the sprite. 1 bpp refers to mode 25, 4 bpp
	  to mode 27, 8 bpp to mode 28,..
Time	- This is the time that Megumi used to decode the picture. The multi-
	  tasking will affect this value. So if you put some load on your
	  machine, Megumi can become much slower.
	  'Aborted' means the decoding ended due to an unexpected error.



Full Screen Display
-------------------
If you choose full screen from the main menu, Megumi enters fullscreen mode.
A suitable mode is choosen to display the picture. You can return by pressing
either ESC or F12 or a menu click.

The F1 key will invoke a small infobox showing the filename of the current
picture. Press F1 again to make it disappear.

You can scroll the picture around with the cursor keys, if it is too large. Use
the cursor keys together with <shift> or <pageup> <pagedown> to scroll more.

In this mode <space> and <backspace> will also select the next and previous
picture.

Note: This mode is fully multitasking. If you are running a hotkey module task
that affects window control (e.g Cool Switch) don't invoke it in full screen
mode. The Wimp will not like that.



Slideshow Mode
--------------
If you try loading a directory, an archive or a filer selection, Megumi enters
the real slideshow mode. A demon is invoked which will either randomly select
pictures to be loaded, or load all pictures in sequence. You have to explicity
terminate the random mode by closing the display window.

The demon will travese all directories and imagefiles in depth-first order.
Files have to be typed correctly or they will be ignored. Autotyping is only
applied to filer selections.

A select click will select the next, an adjust click the previous picture.
The backward advance doesn't work in random mode for obvious reason. Again
this mode is fully multitasking, Megumi is still operational.

Note: Chance has no memory. So it is absolutly possible to see the same
picture four or more times behind each other.



The Choices Window
------------------
The window handling options define how Megumi will react when loading a file.
Tick them all to get ChangeFSI feeling.

Fullscreen zoom allows Megumi to scale down pictures, so they will fit the
choosen screenmode, i.e. she will ignore your zoom settings in fullscreen
mode and select her own.

Automatic filetyping is for Data/DOS files when they were successfully
recognised. This includes the automatic de-typing. Automatic filetyping is
only applied to files dragged from a filer window.



The image formats
-----------------
Megumi can understand the following image formats (in alphabetical order).
_______________________________________________________________________________
ECC	Origin		developed by Mok of The Black Squadron
	Colors		4,8 bpp palette
	Compression	yes
	Recognition	filetype &0c5
			'ECCH'
This is an animated format, but due to the nature of the format, you will not
be able to save the sequence.
_______________________________________________________________________________
GIF	Origin		Graphics Interchange Format
			devised by and copyright of Compuserve Incorporated
	Colors		1,2,3,4,5,6,7,8 bpp palette
	Compression	12-bit LZW
	Recognition	filetype &695
			'GIF87a' or 'GIF89a'
Multiple images in a file are displayed animated. Interlaced pictures will be
faded in. GIF89a extensions are supported.
_______________________________________________________________________________
JPEG	Origin		JPEG File Interchange Format
	Colors		8 bpp grey, 24 bpp true color
	Compression	Discrete cosine compression
	Recognition	filetype &c85
			'JFIF'
Large files may require a huge chunk of memory. Megumi switches from 24bpp to
15bpp, if your machine has not enough memory. Progressive JPEGs are recognised.
But not decoded unless a new version of the RiscOS JPEG module handles them.
______________________________________________________________________________
MAG	Origin		developed on MAKI-chan NET
	Colors		4 bpp palette
	Compression	yes
	Recognition	filetype &0c4
			'MAKI'
______________________________________________________________________________
PI	Origin		developed by Yanagisawa Akira
	Colors		4 bpp palette
	Compression	yes
	Recognition	filetype &0c8
			'Pi'
______________________________________________________________________________
PIC	Origin		developed by Yanagisawa Akira
	Colors		cached
	Compression	Outline
	Recognition	filetype &0c6
			'PIC'
_______________________________________________________________________________
PNG	Origin		Portable Network Graphics format
	Colors		1,2,4,8 bpp palette
			1,2,4,8 bpp greyscale
			24 bpp true color
	Compression	Deflate
	Recognition	filetype &b60
			'PNG'
Only  critical chunks are currently supported, but this may change in future.
Interlaced pictures (4/8 bpp palette) will be faded in.
_______________________________________________________________________________
Sprite	Origin		Acorn defined native image format
	Colors		1,2,4,8 bpp palette
			15,24 bpp true color
	Compression	no
	Recognition	filetype &ff9
			control block verification
Every sprite will get a full palette attached and the mask removed. Multiple
sprites in a file are displayed animated. To work correctly all sprites must
have the same mode and resolution.
_______________________________________________________________________________




Copyright Notice
----------------
This application, 'Megumi', is copyright Dirk Krumbholz, the author, 1997-1998.
The character and illustrations are the copyright property of Lark.

You may not modify, translate, disassemble, decompile, reverse engineer or
create derivative works based upon this application or include whole or part
of this application into other works. 

You may copy this application freely provided that the whole application
remains unaltered, including all the files in the original distribution.
No part of this application, especially the image decoders, may be distributed
separately without permission from the author.

You may not sell this application or include it as a part of a commercial
package without permission from the author. You may not distribute this
application on any CD-ROM or any other high-capacity media, especially if
the media contains images, whithout permission from the author. You may not
distribute this application on any Pay-Site whithout permission from the
author.

This software is supplied 'as is'. The author makes no claims as to its
reliability or suitability for any purpose, regardless of any comments made
elsewhere.  No responsibility can be taken for any failure of the program,
or any loss or damage caused directly or indirectly, or not caused, by the
software.

This application uses the WimpExtension module from Jon Ribbens of DoggySoft.
Try '*help wimpextension' for details.

The Graphics Interchange Format(c) is the Copyright property of CompuServe
Incorporated. GIF(sm) is a Service Mark property of CompuServe Incorporated.



Contacting the author
---------------------
Support is provided via e-mail.

You like Megumi? You have an idea for further improvement?
You have graphic files that won't work? You have a question? 

You can reach me at this adress:

E-Mail: krumbh00@marvin.informatik.uni-dortmund.de



