Pekka J. Toivanen

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This article presents an efficient priority pixel queue algorithm for calculating the distance transform on curved space (DTOCS), the corresponding nearest neighbor transform, and the new projection DTOCS (PDTOCS). The transforms provide tools for approximating distances and finding shortest paths on gray-level surfaces. Surface variation, or roughness, can(More)
The distance transform on curved space (DTOCS) and its locally Euclidean modification weighted DTOCS (WDTOCS) calculate distances along gray-level surfaces. This article presents the Route DTOCS algorithm for finding and visualizing the shortest route between two points on a gray-level height map, and also introduces new distance definitions producing more(More)
In this paper, two new geodesic distance transforms for gray-scale images are presented. The first transform, the Distance Transform on Curved Space (DTOCS), performs the calculation with integer numbers. The second transform, the Weighted Distance Transform on Curved Space (WDTOCS), gives a weighted distance map with real numbers for an arbitrary(More)
In this paper, we present a modification to the back end of vector quantization (VQ), which improves the compression ratio of the lossless compression of multispectral images. By introducing a small change to the back end of VQ, the compression ratio improve significantly. In our expreriments, images were compressed from the original image entropies of(More)