Method and apparatus for using an enlargement operation to reduce visually detected defects in an image

A system comprising:

• a machine-readable storage device having instructions stored thereon;
• and
• a data processing apparatus in communication with the machine-readable storage device and operable to execute the instructions to perform operations comprising:
• performing a scaling procedure on a portion of the document image resulting in an interim image portion;
• displaying the interim image portion;
• initiating a full process of improvement of the portion of the document image comprising
• identifying, using a computing device comprising one or more processors, a plurality of image fragments within the portion of the document image;
• separating, using the computing device, the plurality of image fragments into a plurality of classes, wherein each class of the plurality of classes includes a subset of the plurality of image fragments that are substantially similar to one another;
• for each of the plurality of classes:
• combining, using the computing device, the image fragments for one or more of the classes of image fragments to generate a combined image of the class of the image fragments;
• substantially enlarging, using the computing device, the combined image of the class for one or more of the classes of image fragments to generate an enlarged image of the class of the image fragments;
• filtering, using the computing device, the enlarged image of the class to generate a filtered image of the class of the image fragments;
• generating, using the computing device, an improved portion of the document image by replacing the image fragments within the portion of the document image based on the filtered images of the respective classes of the image fragments.

A storage device having instructions stored thereon that, when executed by a data processing apparatus, cause the data processing apparatus to perform operations comprising:

• performing a scaling procedure on a portion of the document image resulting in an interim image portion;
• displaying the interim image portion;
• initiating a full process of improvement of the portion of the document image comprising
• identifying, using a computing device comprising one or more processors, a plurality of image fragments within the portion of the document image;
• separating, using the computing device, the plurality of image fragments into a plurality of classes, wherein each class of the plurality of classes includes a subset of the plurality of image fragments that are substantially similar to one another;
• for each of the plurality of classes:
• combining, using the computing device, the image fragments for one or more of the classes of image fragments to generate a combined image of the class of the image fragments;
• substantially enlarging, using the computing device, the combined image of the class for one or more of the classes of image fragments to generate an enlarged image of the class of the image fragments;
• filtering, using the computing device, the enlarged image of the class to generate a filtered image of the class of the image fragments;
• generating, using the computing device, an improved portion of the document image by replacing the image fragments within the portion of the document image based on the filtered images of the respective classes of the image fragments.