Archive for March, 2007

Creating HDR images in Krita

27 March, 2007 5 comments

It has been quiet a long time since my last blog entry, but it has also been a long time since I have make presentable progress in Krita’s feature, not that I have been sleeping. But today, thanks to the recent move of the KPlot widget in kdelibs (thanks to Jason and Pino for the hard work on it), I have made good progress on a plugin for creating HDR images (High Dynamic Range) from a set of pictures taken with bracketing. For some better examples of HDR images have a look to the flickr hdr group.

To use this plugin, you need to take a series of images of different exposition but frome the same viewpoints, then the plugin will try to estimate the quantity of light received on each pixel.

The screenshot below shows the dialog:

The plot widget shows the response curve of the camera. It’s allways the same for each camera, and the more picture with different exposure time the better. Unfortunately my camera only allows to take three pictures in a bracketing shot.

One of the nice things you can do with HDR images is to simulate a change of exposure (which is already possible with Krita 1.6):

This image is a good example of where HDR imaging is useless :/ But it seems I have a hard time to create perfectly well aligned images even using a tripod, most of the interesting images I have taken to test HDR are not aligned.

HDR images can then be used for quiet a few nice things, like tone mapping or for realistic motion blur. Krita is capable of neither currently, but I have great hope that thanks to an OpenICC google Summer of Code project it will be easy to add tone mapping to Krita.