Abstract: In an image processor for detecting a circular pattern in an image, input image data is binarized to provide bi-level image data, and pixels having a predetermined value is counted in a block of a polygon having n vertices in the bi-level image data, wherein n denotes a natural number equal to or larger than eight. Then, it is decided, based on a number of the pixels having the predetermined value counted by the counter, whether the circular pattern is detected in the image or not. A detection window is used to detect the specified pattern. The detection window is moved successively by a predetermined number of pixels, in a direction from a side towards the center. The moving distance and direction are controlled based on the result of scan.

Abstract: In an image processor in a print system, an output device processes input data and outputs the processed data, while a detector detects whether data of a specified pattern is included in the input data or in the processed data, in parallel to the data processing by the output device. A stop controller makes the output device stop to output the processed data at an irregular timing after the detector detects the specified pattern. The printer prints an image on a sheet of paper, based on the data outputted by the output device. Thus when the specified pattern in an image is detected, the printing is stopped but the stop position becomes irregular.

Abstract: An image processor detects a specified pattern defined by arrangement of three or more elements. Positions of a plurality of element candidates are detected based on input image data, and n pairs (n?2) of element candidates are selected in the plurality of elements. Then, n arrangement criterions are determined based on the positions of the selected n pairs, and one arrangement criterion is determined based on the n arrangement criterions. By using the one arrangement criterion, positions of all the elements are calculated in the specified pattern. The specified pattern is detected based on the calculated positions of the arrangement.

Abstract: In an image processor in a print system, an output device processes input data and outputs the processed data, while a detector detects whether data of a specified pattern is included in the input data or in the processed data, in parallel to the data processing by the output device. A stop controller makes the output device stop to output the processed data at an irregular timing after the detector detects the specified pattern. The printer prints an image on a sheet of paper, based on the data outputted by the output device. Thus when the specified pattern in an image is detected, the printing is stopped but the stop position becomes irregular.

Abstract: In an image processor for detecting a circular pattern in an image, input image data is binarized to provide bi-level image data, and pixels having a predetermined value is counted in a block of a polygon having n vertices in the bi-level image data, wherein n denotes a natural number equal to or larger than eight. Then, it is decided, based on a number of the pixels having the predetermined value counted by the counter, whether the circular pattern is detected in the image or not. A detection window is used to detect the specified pattern. The detection window is moved successively by a predetermined number of pixels, in a direction from a side towards the center. The moving distance and direction are controlled based on the result of scan.

Abstract: An image processor detects a specified pattern defined by arrangement of three or more elements. Positions of a plurality of element candidates are detected based on input image data, and n pairs (n≧2) of element candidates are selected in the plurality of elements. Then, n arrangement criterions are determined based on the positions of the selected n pairs, and one arrangement criterion is determined based on the n arrangement criterions. By using the one arrangement criterion, positions of all the elements are calculated in the specified pattern. The specified pattern is detected based on the calculated positions of the arrangement.