Abstract A system and method classify a pixel of image data as one of a plurality of image types. A first image characteristic value for the pixel, a second image characteristic value for the pixel, a third image characteristic value for the pixel, and a fourth image characteristic for the pixel is determined. Some of these determinations may be resolution dependent. The values from these determination are utilized in assigning an image type classification to the pixel. Moreover, if at least one of the image characteristic values is greater than a predetermined threshold value the pixel is classified as a halftone peak value. The system includes a plurality of microclassifiers for determining a distinct image characteristic value of the pixel; a plurality of macroreduction circuits connected to the plurality of microclassifiers for performing further higher level operations upon the distinct image characteristic values of the pixel to produce reduced values; and a classification circuit to classify the pixel as an image type based on the reduced values from the macroreduction circuits. The system also includes a circuit to detect flat peaks without detecting multiple peaks and a rectangular blur filtering system.
A method for reducing false halftone detection in image areas having thin lines, comprising the steps of: (a) determining a horizontal video range value for a pixel in a video stream; (b) determining a vertical video range value for a pixel in a video stream; (c) determining a first diagonal video range value for a pixel in a video stream; (d) determining a second diagonal video range value for a pixel in a video stream; (e) determining if at least one value from the group of values consisting of horizontal video range value, vertical video range value, first diagonal video range value, and second diagonal video range value is greater than a predetermined threshold value; and (f) classifying the pixel as a halftone peak value when said step (e) makes a positive determination.
Claim 2
Independent Claim
133 words
A method for reducing false halftone detection in image areas having thin lines, comprising the steps of: (a) determining a horizontal video range value for a pixel in a video stream; (b) determining a vertical video range value for a pixel in a video stream; (c) determining a first diagonal video range value for a pixel in a video stream; (d) determining a second diagonal video range value for a pixel in a video stream; (e) determining if at least one value from the group of values consisting of horizontal video range value, vertical video range value, first diagonal video range value, and second diagonal video range value is greater than a predetermined threshold value; and (f) classifying the pixel as a halftone peak value when said step (e) makes a positive determination.
Claim 3
Dependent Claim
29 words
The method as claimed in claim 1 , wherein said step (a) determines the horizontal video range value for the pixel dependent upon a resolution of the video stream.
Claim 4
Dependent Claim
29 words
The method as claimed in claim 1 , wherein said step (b) determines the vertical video range value for the pixel dependent upon a resolution of the video stream.