Patent ID: 7283673

Claim:
An image processing apparatus comprising at least: input means for carrying out a distribution process of image information associated with an image inputted through an image input mechanism; storing means for storing image information associated with an image input through the image input mechanism; comparing means for comparing image information associated with an image newly input through said image input mechanism with image information associated with an image previously stored in the storing means; output means for outputting from the image processing apparatus pixels generated from the results of comparisons performed by the comparing means; and a positional displacement detecting device for detecting a positional displacement relative to said input mechanism between a source of a previously input image and a source of an image to be newly inputted; wherein the comparing means includes calculating means for calculating a difference in pixel values which represent pixel densities, between image information associated with an image newly inputted through said input mechanism and image information associated with an image previously stored in the storing means, and recognizing means for recognizing a portion common to the stored and newly input images by comparing an output of the comparing means with a preset threshold value; wherein the comparing means includes extracting means for causing the output means to output from the image forming apparatus only pixels corresponding to pixels of the stored and newly input images respectively recognized by the recognizing means when the difference in pixel values calculated by the calculating means is equal to or less than said preset threshold value and wherein a warning of a positional displacement relative to said input mechanism between a source of a previously input image and a source of an image to be newly inputted is provided on a display means in a case where a positional displacement is detected by said positional displacement detecting device.