Volume Rendering of rgb-image

This project was implemented while working on this paper. The render displays an three channel volumetric dataset, i.e. each voxel contains an RGB color instead of a scalar density. In Visible Human project a so called cryo-data was obtained by slicing a frozen cadaver and capturing each slice with photo camera to make an anatomical atlas of human body. I obtained the data from here - an interesting web-viewer by the way. Volume size is 920x840x561 voxels. When rendering I made the black voxels transparent because they mainly correspond to the air.

The approach was to index colors: instead of loading on GPU a 24-bit RGB volume data I used a 8-bit volume plus a color table. The problem was to minimize the image quality loss by finding an optimal 256 colors for the color table. To assess the image quality I have made a small program on javascript to compare two images with PSNR metrics.

Download demo (120Mb)

Download paper

Volume Rendering of rgb-image

Measuring image quality with PSNR metrics