Fingerprint Image Mosaicing Direction Detection

The patent applies preliminary action by comparing leading and trailing image blocks before performing mosaicing to identify the sweep direction. This pre-processing step determines whether the finger swept forward or backward, allowing the system to adjust the mosaicing direction accordingly. The affinity comparison between corresponding blocks in sequential frames is performed beforehand to establish the correct capture direction, ensuring reliable image reconstruction without requiring complex real-time adjustments during mosaicing.

The patent implements self-service by enabling the system to automatically identify and determine the sweep direction through affinity comparison of image blocks, eliminating the need for user intervention. The algorithm autonomously analyzes the correlation between leading and trailing blocks in sequential frames, calculates affinity values, and determines the capture direction without requiring the user to manually indicate whether they swept forward or backward. This self-determining mechanism maintains capture accuracy while significantly improving ease of operation.

The patent applies the extraction principle by focusing the affinity comparison only on specific leading and trailing image blocks at the boundaries of sequential frames, rather than comparing all image blocks throughout the entire frame. This selective extraction of critical boundary blocks for comparison significantly reduces the computational workload while maintaining accurate sweep direction identification. The method extracts only the necessary information from frame boundaries where directional changes are most evident, avoiding unnecessary computations in the interior regions of the images.