Hello World. In this inaugural post, I wanted to describe what we’re all about here at AT Research.  But rather than bombard you with jargon and mission statements, about cutting-edge rendering paradigms, highly-scalable volumetric acquisition processing pipelines, and Six-Sigma proven performance platforms, I think it would be best just to describe a type of problem we’re addressing.  Today, we’re going to discuss rendering X-Rays.

Here are some real x-rays to use for comparison while we look some commercial artwork.

Example 1: Stylized

   The classic glowing green xray look is show here in this classic clip from Total Recall (1990). 

A close up…

   This was quite a nice effect for eighteen years ago.  It looks quite cartoonish today. Yet almost nothing has changed, except the greenish tint is replaced by a glowing blue. 

This example is even less effective as an x-ray. First of all there is a light source as if this is a regular photograph.  Then there is an unrealistic shader applied to the models.  The opacity of the bones is controlled not by the density of the medium, but by the normal of the surface perpendicular to the camera.  Also there are no other tissues modelled here, only bones.

Here we have another blue illustration. The models are even less accurate. And the shading is also unconvincing. Yet if you browse through medical illustration catalogs, this style is widely used. It’s cheap and quick for the artist to apply and let the viewer see inside.  Yet I doubt that an airbrush artist would make the same decisions in the jaw and eye sockets as these x-ray shaders.

Example 2: Retouched Film

Creating more realistic x-ray renderings in typical software packages isn’t easy.  So clever advertising campaigns might use real x-ray films and digitally pose the person into an activity. Or you can convince people to subject themselves to radiation in the pose itself, like Wim Delvoye.  While the individual bones look much better than the previous example, the artist is transforming the bones in only two dimensions. It’s also quite easy to create incorrect poses for human joints. 

So that’s a taste of the type of problem we work on.

In a later post I will go into the details of what happens in a real X-ray exposure and how to recreate this phenomenon in software.

Thanks,

Ben Lipman
Anatomical Travelogue R&D