[svn.haxx.se] · SVN Dev · SVN Users · SVN Org · TSVN Dev · TSVN Users · Subclipse Dev · Subclipse Users · this month's index

Re: Re: TortoiseIDiff - Comparison

From: Ivan-Assen Ivanov <ivanassen_at_gmail.com>
Date: 2006-09-29 10:01:07 CEST

On 9/29/06, Hans-Emil Skogh <Hans-Emil.Skogh@tritech.se> wrote:
> >> To implement any image comparisons, one needs
> >> pixel-access to the images.
> ...
> > But you can always convert that image into a DiB
> > and then manipulate it from there.
> ...
> >> The best way would be if we could create a way to
> >> get the raw data from the CPicture class. Today
> >> that's not possible as I see it.
> I might have been wrong about CPicture. The Bitmap-class used to store
> all images except icons today has GetPixel()/SetPixel()-methods. Those
> could be exposed from CPicture and utilized.
> In conjunction with a way to create a CPicture instance containing a
> blank image of given dimensions everything needed is in place.
> (Efficient enough? Don't know. Time will tell...)

Attempts to use SetPixel/GetPixel for general image processing or even
pulling the raw data out of an image class are usually disastrous in
terms of performance. You're incurring a hit of millions of [possibly
virtual] function calls, address calculations and God knows what else
on top of the real processing you need to do.

To unsubscribe, e-mail: dev-unsubscribe@tortoisesvn.tigris.org
For additional commands, e-mail: dev-help@tortoisesvn.tigris.org
Received on Fri Sep 29 10:01:13 2006

This is an archived mail posted to the TortoiseSVN Dev mailing list.

This site is subject to the Apache Privacy Policy and the Apache Public Forum Archive Policy.