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Voxel

Webopedia Staff
Last Updated May 24, 2021 7:58 am

Short for volume pixel, the smallest distinguishable box-shaped part of a three-dimensional image.

Voxelization is the process of adding depth to an image using a set of cross-sectional images known as a volumetric dataset. These cross-sectional images (or slices) are made up of pixels. The space between any two pixels in one slice is referred to as interpixel distance, which represents a real-world distance. And, the distance between any two slices is referred to as interslice distance, which represents a real-world depth.

The dataset is processed when slices are stacked in computer memory based on interpixel and interslice distances to accurately reflect the real-world sampled volume.

Next, additional slices are created and inserted between the dataset’s actual slices so that the entire volume is represented as one solid block of data.

Now that the dataset exists as a solid block of data, the pixels in each slice have taken on volume and are now voxels.

For a true 3D image, voxels must undergo opacity transformation. Opacity transformation gives voxels different opacity values. This is important when it is crucial to expose interior details of an image that would otherwise be hidden by darker more opaque outside-layer voxels.

Voxel images are primarily used in the field of medicine and are applied to X-Rays, CAT (Computed Axial Tomography) Scans, and MRIs (Magnetic Resonance Imaging) so professionals can obtain accurate 3D models of the human body.

Voxel imaging is also being used to create computer games, so 3D acceleration is not necessary.