| 摘要 |
PURPOSE:To prevent a ruled-line display from being absent when image data are reduced and displayed by discriminating a ruled-line part and other parts according to the frequency distributions of vertical and horizontal illuminating pixels of the image data and reducing the image data so that the ruled-line part is left. CONSTITUTION:The numbers of the vertical and horizontal illuminating pixels of the image data, which are stored in the memory of an arithmetic part 2 and not reduced yet, are detected to extract the ruled-line part. In this case, the ruled-line part is extracted by setting flags for the numbers of rows and columns showing frequency distributions exceeding a threshold value as the reference value for discriminating between the ruled-line part and other parts. Then, the ruled-line part which is discriminated from other data and has its flag set is processed. In this case, illuminating pixels are preferentially extracted nearby the columns and rows whose flags are set by this image data reducing method without fail, so the absence of the ruled-line part on a reduction screen can securely be prevented. |
