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Banana99
26th Jan 2003, 20:12
does anyone know why IE6 allows me the choice of saving things as GIF or BMP on some images but only BMP on others.

The two images are both GIFs

PaperTiger
27th Jan 2003, 00:20
An animated .gif cannot be saved as a .bmp file.

Banana99
27th Jan 2003, 02:05
the problem is it's a gif that refuses to be saved as a gif! - only a bmp.

so your observation is correct of course - but not relevant to this problem.

PaperTiger
27th Jan 2003, 04:11
Beats me then, ask the designers of IE6. While you're there I have a few other questions for them :D

Post the URL, I'll see if IE4 handles it.

bblank
27th Jan 2003, 19:39
The two images are both GIFs.

Are you sure? A GIF file is determined by the compression
algorithm used, not by the "GIF" extension. An intelligently designed
graphics program will ignore any filename extension and read the
file's header (which is embedded in the file itself) to determine the
decompression routine that is needed.

GIF is a Service Mark property of CompuServe, the GIF format is
the copyright property of CompuServe, and Unisys holds the
patent on the the LZW compression algorithm on which the
"Graphics Interchange Format" is based. When the internet was
young Unisys would rattle its royalty swords every couple of years.
For that reason many graphics programs refuse to convert to GIF format
any file not already imported as a GIF.

Finally, just because a file looks like a GIF and quacks like a GIF, it
doesn't necessarily follow that the file is a true (copyright-protected) GIF.
I create many "GIF" files that have the GIF extension, that have GIF
headers that fool graphics programs into thinking they are true GIFs,
that are properly decompressed by LZW decompression, but which
are not true GIFs because they are not compressed by means of the
patented algorithm. Haven't been sued yet ;)

Banana99
30th Jan 2003, 23:42
Thanks for the replies.

I was going to post the URLs just now and (surprise sur-****ing-prise) all is working now.

Answers on a postcard please.