Abstract: During laser printing, the semiconductor chip may suffer many defects, such as character tilt and incorrect character position. To address these defects, a character-region positioning method for multiple semiconductor chip-images was proposed based on improved convex hull detection. Firstly, multiple semiconductor-chip images were obtained using a three-axis image acquisition platform, and several single-chip images were segmented and extracted. Secondly, the Harris corner detection was employed to produce the image corner distribution map, and the convex hull detection algorithm was improved. Then, the corners in non-character regions were eliminated, and the outermost corner convex hull line was acquired. Finally, the minimum enclosing rectangle of the convex hull was fitted, and the character region was positioned. The experimental results reveal that, compared with the morphological filtering positioning method, the positioning method based on edge features, that based on character texture features, and that based on convex hull and the minimum external moment, the proposed method can more accurately position the chip’s character region, and the average running time of the single-chip image is less than half of the above-mentioned methods. Therefore, this proposed method can effectively reduce the computing load and improve the computing efficiency. 

Key words:  , Harris corner detection, improved convex hull detection, character positioning