DEVELOP3D - Technology for the product lifecycle

Ok - so I wasn’t all that quick with the update to this series (first part is here) - magazine deadlines and trips to Legoland got in the way, along with an all too brief spell of sunny weather that just itched to be taken advantage of. Anyway, back on the subject of rendering - and what I want to talk about this time around is HDR images and their use in rendering.

If you want Wikipedia’s version of the truth, it’s this:

High Dynamic Range Imaging (HDRI or just HDR) is a set of techniques that allow a greater dynamic range of luminances between the lightest and darkest areas of an image than standard digital imaging techniques or photographic methods. This wider dynamic range allows HDR images to more accurately represent the wide range of intensity levels found in real scenes, ranging from direct sunlight to faint starlight. Source: http://en.wikipedia.org/wiki/High_dynamic_range_imaging

To put it another way, in my own words:

HDR stands for High Dynamic Range, in opposition to Low Dynamic Range images, or pretty much every graphics format out there. The difference between the two relates to the amount of data the image file stores about the intensity of the light in an image. Whereas standard image formats capture a scene based purely on colour, HDR images also capture a lot of information about the intensity of the light at each pixel, as well as colour. While they’re used in photographic circles, their use has become widespread in computer graphics technology because they can be used to capture and reuse light in a much more efficient manner. They’re most commonly used in combination with spherical panorama style images which capture a full 360 degree image of a particular situation or scene. Source: Me.

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