A fast and efficient correction technique for slant images

In many image processing applications, such as OCR and object analysis, the input image is often inclined. For the subsequent processing and analysis, geometric correction is the most part in pre-processing phase. For the image or scanned document which is rectangular or near-rectangular, if its corner(s) is/are missing or folding, to find the real inclination angle of image or document is time consuming by previous techniques. In this paper, we proposed a fast and efficient algorithm to find the inclination angle of such an image or document. Experiments show that the correction results for the inclined image or scanned document by proposed technique are perfect. Compared with the previous algorithms, the amount of calculation has been greatly reduced, so it is suitable for real-time correction of slant images, such as scanned financial note, vehicle license plate, and text document.