Method and apparatus for segmentation of compound documents having low resolution halftones

A method of segmenting a compound document for enhancement during replication of the compound document, comprising:

• filtering data representing a portion of the compound document through a filter associated with a first resolution;
• filtering the data representing the portion of the compound document through a filter associated with a second resolution;
• detecting edges on both, an output of the filter associated with the first resolution and an output of the filter associated with the second resolution;
• combining data representing detected edges from both outputs;
• and
• determining whether a pixel corresponding to the data representing the detected edges is over a halftone region.

A computer readable medium having program instructions for segmenting a compound document for enhancement during replication of the compound document, comprising:

• program instructions for filtering data representing a portion of the compound document through a filter associated with a first resolution;
• program instructions for filtering the data representing the portion of the compound document through a filter associated with a second resolution;
• program instructions for detecting edges on both, an output of the filter associated with the first resolution and an output of the filter associated with the second resolution;
• program instructions for combining data representing detected edges from both outputs;
• and
• program instructions for determining whether a pixel corresponding to the data representing the detected edges is over a halftone region.

An image replication system, comprising:

• a labeling module configured to segment image data corresponding to a compound document, the labeling module including,
• multiple branches including edge detection modules for detecting edges of the compound document, a plurality of the multiple branches capable of filtering the image data at different resolutions;
• logic for combining output of at least two of the multiple branches in order to initially identify a portion of the compound document as a halftone portion;
• and
• a counting module configured to count pixel values within a neighborhood to determine whether the initially identified halftone portion is finally labeled as a halftone region.

An integrated circuit capable of segmenting image data corresponding to a compound document, comprising:

• labeling circuitry configured to identify an image data region type, the labeling circuitry having multiple branches, each of the multiple branches including,
• filter circuitry capable of filtering the image data, each of the multiple branches associated with a different filter resolution;
• and
• edge detection circuitry configured to detect edges of the filtered image data;
• the labeling circuitry further including, circuitry for combining at least two outputs of the multiple branches;
• and
• circuitry for identifying the image data region type based upon a value defined through the circuitry for combining the at least two outputs of the multiple branches.