Archive for April, 2007

Aligning images (2)

20 April, 2007 4 comments

I have been making some progress on image adjustment, I am now able to estimate the distortion parameter and to correctly position the images:

The main problem I got was that I was trying to estimate the distortion parameters with two different set, one for the first image, and one for the second. The goal was to be the most general as possible, in case some one wants to create an image with pictures taken with different lens (or with a different focal distance), but it’s definitively not the most common use case, so it probably don’t fit in Krita’s use case for panorama creation.

The difference of color is caused because I use a naive blending algorithm, I will need to have a look at enblend to see how to improve that.

Weab, kalculus, WaterFlow

12 April, 2007 3 comments

In parallel of hacking on Krita, for quiet some time, I have been working on three small applications, written in ruby and Qt4, and today I feel it was time for a joint release of the code, even if it’s early alpha software.


I have let my personal page dye when I started engineering school around five years ago, mostly by lack of motivation, and also because I wanted to rewrite the engine on a cleaner base, it use to be a php script that would read the content from text files and fill a template. The php wasn’t really needed but at the time it felt like the easiest way to do. As I don’t really need something dynamic, for the rewrite, I wanted to do the filling of the templates off-line, using a bunch of scripts.
But then, at work, I got a MacBook including Apple’s ilife, which includes iweb, which is a nice application for easily create a small homepage and publish photos gallery. And that gave me the idea to put a GUI front end to my bunch of scripts and to call that Weab (the fusion of Web and Easy).

But why an other tool ? I didn’t find a tool that did what I want and only what I want. And there is already Quanta for KDE ! Yes but my opinion is a really nice development tool for websites. But it’s really heavy if you want to have a small homepage with few text pages and publish some pictures.

If you want to have a look at it version 0.1 is available here.


Kalculus is an application I have already started to write twice in C++, and never found the time to have more than something that just work. It’s a front-end for tools like yacas or octave (they are already some qt/kde based octave front-end, but )

Currently only yacas support is available. But octave support should be available shortly.

If you want to have a look at it version 0.1 is available here.


WaterFlow is more a library, whose goal is to provide a way to create algorithms by creating a graph. The goal is to integrate it in Krita, and provides an easy way to create new filters or test a combination of effects.

Currently it’s mostly a framework, with some design flaw for what I want to do with it in Krita, nothing very exiting, but a nice start if you are interested by this way of creating algorithms.

If you want to have a look at it version 0.1 is available here.

On other news, I am preparing to make a release of krita-plugins with a few goodies.

Aligning images

2 April, 2007 5 comments

Image alignment has quiet a lot of applications, for instance for creating panoramas. Or when creating HDR images from a bracketing when images weren’t perfectly taken from the same position. And I want something simple, one click and done. Hugin is a good tool for creating panorama, but you need a degree of computer science with a major in panorama creation to achieve a good enough result.

It’s a feature I wanted to have for 1.6, but at the same time I started to work on 1.6 features, my PHD director ask me to work on a similar stuff, and working on the same thing during the day and during the evening is not something I am capable of doing. So I left some unfinished code sleeping for almost a year and decided to resurrect it last week. The two images below were automatically aligned:

The problem is that the pictures are slightly distorted, that’s why they don’t perfectly blend into each other. This need to be corrected, which is the next step I will be working on.