Determination of Edges by Automatic Threshold Value Generation?

As the superior performance of canny algorithm it is most widely used now days. As it is based on frame level static its accuracy is higher than that of other edge algorithms. We proposed a algorithm to perform canny algorithm at block level with edge detection performance compared with original frame level canny algorithm. Directly applying the original Canny algorithm at the block-level leads to excessive edges in smooth regions and to loss of significant edges in high-detailed regions since the original Canny computes the high and low thresholds based on the frame-level statistics. To avoid such problems we proposed this algorithm to detect edge based on block type and local distribution of gradients in image block. In this algorithm it uses a uniform gradient magnitude histogram to compute block based hysteresis threshold. The resulting block-based algorithm has a significantly reduced latency and can be easily integrated with other block-based image codec’s