JPH0315970A - Mark input device - Google Patents

Abstract

PURPOSE:To prevent the deterioration of mark recognition rate when there is an inclination in a having read mark sheet by detecting the inclination of the having read mark sheet and executing a correction processing. CONSTITUTION:A mark sheet read part 11 outputs a read image signal (a) by scanning the mark sheet. An inclination detection part 12 obtains a difference between the number of lines under an inclination detection mark from the read image signal (a) and outputs it as an inclination line number signal (b). An inclination correction part 13 inputs the inclination line number signal (b) and the read image signal (a), executes the inclination correction processing and outputs an inclination correction image signal (c). The inclination correction processing is executed by switching the number of reference lines in the read image signal (a) in accordance with the number of the inclination lines so as to take out data. Thus, the deterioration of the mark recognition rate can be prevented even if there is the inclination at the time of reading the mark sheet.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a mark input device, and particularly to countermeasures against inclination when reading a mark sheet. 2. Description of the Related Art Conventional mark input devices take measures against tilting when reading a mark sheet by using a mechanical section that inputs the mark sheet. Problems to be Solved by the Invention In the conventional mark input device described above, countermeasures were taken against the inclination of the mark sheet when reading the mark sheet by the mechanism unit that inputs the mark sheet, so this method is applicable to devices such as facsimile machines where input documents are often skewed. In this case, the disadvantage is that the mark recognition rate decreases. The present invention has been made in view of the above-mentioned conventional situation,
Therefore, it is an object of the present invention to provide a novel mark input device that eliminates the above-mentioned drawbacks inherent in the conventional technology and can prevent a decrease in mark recognition rate even when applied to facsimile. ．． Means for Solving the Problems In order to achieve the above object, the mark input device according to the present invention is arranged at a constant interval 1 at both ends of the beginning of the mark sheet in order to detect the skew inclination when reading the mark sheet. A mark sheet reading section that outputs a read image signal by reading a mark sheet having skew detection marks; and a mark sheet reading section that outputs a read image signal by reading a mark sheet having skew detection marks; A skew detection section outputs a line number signal, a skew line number signal and a read image signal are input, and the slope of the skew is calculated based on the ratio of the number of skew lines and the interval g between the skew detection marks. A skew correction unit that switches the number of reference lines in a read image signal according to the inclination and extracts image data and outputs it as a skew correction image signal, and a mark detection unit that inputs the skew correction image signal and performs mark detection processing. It is prepared and configured. Embodiment Next, a preferred embodiment of the present invention will be specifically explained with reference to the drawings. FIG. 1 is a block elliptical diagram showing one embodiment of the present invention. Referring to FIG. 1, reference numeral 11 is a mark sheet reading section, into which the mark sheet 15 shown in FIG. 2 is input, and by scanning the mark sheet 15, outputs a read image signal a. 12 is a skew detection section;
The difference in the number of lines at the lower end of the skew detection mark 16 is determined from the read image signal a, and is output as a skew line number signal b. 13 is a skew correction section which receives a skew line number signal and a read image signal and performs skew correction processing;
Outputs the skew correction image signal C. The skew correction process is
This is done by switching the number of reference lines in the read image signal according to the number of diagonal lines and extracting the image data. FIG. 2 is a schematic diagram showing a part of an elliptical example of a mark sheet in the present invention. In FIG. 2, 15 is a mark sheet, which has skew detection marks 16 arranged at a constant interval 1 at both ends of the beginning. It is assumed that the positions of the skew detection marks 16 at both ends in the sub-scanning direction are the same. The reference line is determined as follows. When the number of diagonal lines is T, and the slope is upward to the right, T pixels located at a distance n to the right from the left edge of the image refer to line 1, which is -xn lines before the current line. Similarly, if the slope is upward to the left, a pixel at a distance of n to the left from the right edge of the image refers to the line -×n lines before the current line. The skew correction image signal C output from the skew correction section 13 is input to the mark detection section 14, and mark detection processing is performed on the skew correction data. Effects of the Invention As explained above, according to the present invention, by detecting the inclination of the read mark sheet and performing correction processing,
Since the mark recognition rate does not decrease even if the scanned mark sheet is tilted, it can be applied to devices such as facsimile machines where the input document is often tilted.

[Brief explanation of the drawing]

Figure 1 is a block diagram showing one embodiment of the present invention. DESCRIPTION OF SYMBOLS 11... Mark sheet reading section, 12... Skew detection section, 13... Skew correction section, 14... Mark detection section, a... Edge removal image signal, b... Skew Line number signal, C... skew correction image signal FIG. 2 is a diagram showing a part of an example of the structure of a mark sheet according to the present invention.

Claims (1)

[Claims] In a mark input device that reads a mark sheet having two skew detection marks arranged at a constant interval on both ends of the mark sheet in order to detect skew when reading the mark sheet, a mark sheet reading section that inputs the mark sheet and outputs a read image signal. a skew detection section that detects a positional shift in the sub-scanning direction of the two skew detection marks from the read image signal and outputs the detected position as a skew line number signal; a skew correction section that calculates the skew inclination based on the interval ratio, switches the reference line in the read image signal according to the skew inclination, and outputs the skew correction image signal as a skew correction image signal; 1. A mark input device comprising: a mark detection section that performs mark detection processing.