Nautilus + TIF file = memory insanity
Tom Mitchell
mitch48 at sbcglobal.net
Sat May 15 00:51:58 UTC 2004
On Tue, May 11, 2004 at 09:26:20AM -0700, Billy Charlton wrote:
> > The images size (not file size) is huge:
> >
> > mustang:~/downloads> identify sfstreets.tif
> > sfstreets.tif TIFF 11248x14484+0+0 PseudoClass 2c 8-bit 209.4kb 1.570u 0:02
> >
> > That's like 164 times the area (in square pixels) of my monitor!
> >
> > I have no idea how to make those programs more efficient. Can you
> > make do with a scaled down image? I scaled it down to 20% in the
> > gimp and it is very readable at 2250x2897. I guess it depends on your
> > application as to whether this is acceptable.
There was a discussion about 'risks' associated with exploding files
exactly like this. "Decompression bombs" they called them.
See ftp.aerasec.de/pub/advisories/decompressionbombs/
In "pictures" you will see giff and png versions of the same
problem.
Some compression tools are very good on silly data and
the resulting decompression bomb effect is astounding.
$ bzip2 -v zarro
zarro: 685000.000:1, 0.000 bits/byte, 100.00% saved, 100010000 in, 146 out.
$ ls -l
-rw-rw-r-- 1 mitch mitch 100010000 May 14 17:46 zarro
$ ls -l
-rw-rw-r-- 1 mitch mitch 146 May 14 17:46 zarro.bz2
Astounding....
146 bytes --grows to--> 100010000
--
T o m M i t c h e l l
/dev/null the ultimate in secure storage.
More information about the test
mailing list