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Subject: Re: [boost] GIL io_new review
From: Domagoj Saric (domagoj.saric_at_[hidden])
Date: 2010-12-10 14:27:22

"Mateusz Loskot" <mateusz_at_[hidden]> wrote in message

>>> 4. Cutting TIFF to PNG involves compression. If we are interested in
>>> raster access, RIO, I/O speed, perhaps we could stick to TIFF as
>>> output format as well. What you think?
>> That depends on what exactly are we trying to test here, the C++
>> wrappers (e.g. io_new vs io2) and/or the backends (e.g. LibTIFF vs WIC)
>> and/or something third...
> Actually, that was part of my initial question.

Hi, sorry for the delay...

I went and tested ahead just to see what we are dealing here...

This code (io2 using the WIC backend,
unfortunately large TIFF support was added only to the latest WIC available
on Windows 7 so the same code will not work on WinXP) opens the input TIFF
and hacks it up into separate tile files.
With an Intel i5_at_4.2 GHz with 4 GB RAM I got the following results:

200x200 PNG tiles ~ 65 seconds
512x512 PNG tiles ~ 69 seconds
512x512 TIFF tiles ~ 27 seconds

RAM usage was below 5 MB the whole time (after working around an apparent
leak in WIC that otherwise cause the RAM usage to crawl up to ~15 MB) and
the binary is about 45kB...

... I guess these tasks are no longer so hard for modern hardware as my work
desktop churns them out pretty fast...

"What Huxley teaches is that in the age of advanced technology, spiritual
devastation is more likely to come from an enemy with a smiling face than
from one whose countenance exudes suspicion and hate."
Neil Postman 

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