For the future -- lcms and big images

[Bart Coppens]

On Monday 06 February 2006 12:05, Boudewijn Rempt wrote:
> If we're trying to load a big image that needs converting, either because
> it doesn't have the display profile or because it's not 8-bit rgb, we
> convert every pixel, and krita would be much faster if we'd scale first and
> then apply cmsDoTransform.
There are other reasons as well. Trying the oldfashioned way to debug big 
speed problems (Ctrl+C in gdb when Krita seems 'hang' loading a 3000x3000 
file), I get a lot of times that my Ctrl+C hits a codepath like
#5  0x00002aaaaf29093a in XPutImage () from /usr/X11R6/lib/libX11.so.6
#6  0x00002aaaad6b6bba in QPixmap::convertFromImage () 
from /usr/lib/libqt-mt.so.3
#7  0x00002aaaad770856 in QPainter::drawImage () from /usr/lib/libqt-mt.so.3
#8  0x00002aaab0a4e487 in KisImage::renderToPainter (this=0x1123130, x1=0, 
y1=0, x2=2999, y2=2999,
and so. Meaning that we'd probably make krita not only faster in the lcms 
path, but also in the Qt path as well. Just so that you know :)

Bart