3D Photos - Montreal subway station

Here, I am gonna demonstrate what effects alpha and the truncation value have on the depth map when using Depth Map Automatic Generator 5 (DMAG5). The closer alpha is to 0, the more the dissimilarity between potential matching pixels comes from the color of the pixels. The closer alpha is to 1, the more the dissimilarity between potential matching pixels comes from the color gradient. The color gradient is usually preferred due to difference in illumination between the left and right images. The truncation is there to reduce the effects of occlusions. Maybe have a look at Fast Cost Volume Filtering for Stereo if you need more explanations about those parameters.

Left image.

Right image.

The minimum disparity is set at -28 and the maximum disparity at 0. Unless indicated otherwise in the following captions, the radius is 12, alpha is 0.9, the truncation value for the color is 7, the truncation value for the gradient is 2, the value for epsilon is 4, and the number of smoothing iterations is 1.

Depth map.

Depth map with alpha = 0.5.

Depth map with alpha = 0.1.

Let's go back to alpha = 0.9.

Depth map with truncation (gradient) = 4.

Depth map with truncation (gradient) = 8.