[comp.sys.amiga] IFF format - HELP

sjeyasin@axion.bt.co.uk (swaraj jeyasingh) (12/19/90)

Could someone explain if there is a difference between IFF text files and
IFF graphic files and what, if any, ILBM has to do with the latter. I have some
applications which claim to read IFF files and others which claim to produce
IFF output but I cant get them to understand each other. The only difference is
that one is text and one is a picture. I notice that some pics are said to be in
IFF ILBM format. Is this a different format from plain IFF or am I reading
wrong?  How can I find out ? Any help gratefully accepted

Confused,

Swaraj Jeyasingh

peterk@cbmger.UUCP (Peter Kittel GERMANY) (12/19/90)

In article <1990Dec18.170031.17134@axion.bt.co.uk> sjeyasin@axion.bt.co.uk writes:
>
>Could someone explain if there is a difference between IFF text files and
>IFF graphic files and what, if any, ILBM has to do with the latter. I have some
>applications which claim to read IFF files and others which claim to produce
>IFF output but I cant get them to understand each other. The only difference is
>that one is text and one is a picture. I notice that some pics are said to be in
>IFF ILBM format. Is this a different format from plain IFF or am I reading
>wrong?  How can I find out ? Any help gratefully accepted

There is a sort of hierarchy: IFF is the general name on top of all.
Below this you have variants for text, pictures, sound, and much more.
The normal format for pictures is IFF ILBM (though there are also
other variants like IFF ACBM and perhaps some more, that are specialized
for some application or another). And again an IFF ILBM can hold all 
the different graphics resolutions the Amiga provides, so they can
look considerably different. (Or you may use data compression or not,
just as you want to program it.) - For text there is a format IFF FTXT.

IFF is fully documentend in the RKM books by Addison-Wesley, volume
Includes & Autodocs. You can find these documents also on a Fish disk.

To find out what your actual files are, go into Shell (or CLI) and type:
     type  filename  hex
and look only at the first output line (break very soon with Ctrl-C).
On the right side, this may look like
     FORM....ILBMBMHD
             ^^^^
Now this ILBM tells you that this is a picture file (or a brush).
If you find FTXT here, then it is a text file.

-- 
Best regards, Dr. Peter Kittel  // E-Mail to  \\  Only my personal opinions... 
Commodore Frankfurt, Germany  \X/ {uunet|pyramid|rutgers}!cbmvax!cbmger!peterk

monty@sagpd1.UUCP (Monty Saine) (12/22/90)

	On a related note, does there exist an utility to "repair"
	munged IFF files? I have run into problems reading the 
	bynery posting IFF files for the A1000 hard drive expansion
	and in reading IFF output files from Draw Plus. As soon as
	I solve this I'll have the A1000 autoboot piggy back files
	ready to post.
	
	Is there and IFF Editor? something that would inspect an IFF
	file and allow possible correction of what ever is not on the
	up and up?

	Monty Saine