Semi-global stereo correspondence processing with lossless image decomposition

An apparatus comprising:

• means for capturing a stereoscopic image;
• and
• means for computing aggregated disparity costs for a base image of the stereoscopic image,
• wherein the means for computing aggregated disparity costs is configured to:
• compute path matching costs for external paths of at least some boundary pixels of a tile of the base image, wherein a boundary pixel is a pixel at a boundary between the tile and a neighboring tile in the base image;
• store the path matching costs for the external paths;
• compute path matching costs for pixels in the tile, wherein the stored path matching costs for the external paths of the boundary pixels are used in computing some of the path matching costs of some of the pixels in the tile;
• and
• compute aggregated disparity costs for the pixels in the tile, wherein the path matching costs computed for each pixel are used to compute the aggregated disparity costs for the pixel.

A non-transitory computer readable medium storing software instructions that, when executed by a processor, cause the performance of a method for disparity cost computation for a stereoscopic image, the method comprising:

• computing path matching costs for external paths of at least some boundary pixels of a tile of a base image of the stereoscopic image, wherein a boundary pixel is a pixel at a boundary between the tile and a neighboring tile in the base image;
• storing the path matching costs for the external paths;
• computing path matching costs for pixels in the tile, wherein the stored path matching costs for the external paths of the boundary pixels are used in computing some of the path matching costs of some of the pixels in the tile;
• and
• computing aggregated disparity costs for the pixels in the tile, wherein the path matching costs computed for each pixel are used to compute the aggregated disparity costs for the pixel.