Criteria for an imageviewer

[Torsten Rahn]

Am Freitag, 3. Juni 2005 14:40 schrieb Boudewijn Rempt:
> On Friday 03 June 2005 13:06, Torsten Rahn wrote:
> > If you want a rather extreme testcase use this as a reference:
> > http://photojournal.jpl.nasa.gov/tiff/PIA03377.tif
> Ha, Krita can load that! 

Congrats! ;-)

> And it takes only 350mb when loaded, though 
> somewhat more while loading.

Well, this seems wasteful to me as the user doesn't actually see the whole 350 
MB of data at any point of time at once. So in case the user looks at the 
whole image it shouldn't be necessary to load the whole data but just those 
few kB of spot check data that you need to generate the scaled down view (and 
to make sure that it can react snappy to some zoom-in maybe a bit more data 
in advance).
Of course this probably doesn't work for all kinds of imageformats (but it 
should definetely work for all image formats which are close to uncompressed 
raw-image formats e.g.). If the user looks at parts of the image it might 
make sense to only load the respective part of the image file.
Of course one has to find a good compromise  between memory usage and 
snappiness but I doubt that loading the whole file into memory beforehand is 
the best solution. 

-- 
Mit freundlichen Grüßen / Kind regards,

        Torsten Rahn

--
Dipl.-Phys. Torsten Rahn, credativ GmbH
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