Image enhancement employing partial template matching

• US 7,711,202 B2
• Filed: 08/12/2008
• Issued: 05/04/2010
• Est. Priority Date: 07/23/2003
• Status: Expired due to Fees

• Current Assignee: Marvell International Technology, Ltd. (Marvell Technology Group Limited)
• Original Assignee: Marvell International Technology, Ltd. (Marvell Technology Group Limited)
• Inventors: Keithley, Douglas Gene
• Primary Examiner(s): PATEL, KANJIBHAI B
• Application Number:
  US12/190,469
• Publication Number:
  US 20090041369A1
• Time in Patent Office: 630 Days
• Field of Search: 382/176, 382/209, 382/254, 382298-300, 382/305, 382/312, 358/1.1, 358/1.2, 358/1.6, 358/1.9, 358/3.27, 358/518, 345/613
• US Class Current: 382/254
• CPC Class Codes: G06T 2207/10008 from scanner, fax or copier
• CPC Class Codes: G06T 2207/20012 Locally adaptive
• CPC Class Codes: G06T 5/00 Image enhancement or restoration
• CPC Class Codes: H04N 1/4092 Edge or detail enhancement

Abstract

A method of image-resolution enhancement employing partial-template matching, including storing at least a portion of an image, and selecting from the image a window comprising a plurality of adjacent line segments having pixels, the window including a target pixel. The method also includes comparing the pixels of the window with a template for a partial match, and responsive to a partial match being found, substituting an enhancement pixel for the target pixel. By allowing a partial match for enhancement instead of requiring a 100-percent match of the prior art, the method provides image-resolution enhancement for digital-image data having noise or other errors.

Claims

1. A computer system comprising:

a memory; and

a circuit operable to

store at least a portion of an image as pixels in the memory;

select a window comprising a plurality of adjacent pixels forming line segments of the image, wherein the window includes a target pixel;

select at least one template from a plurality of templates, at least two of the templates of the plurality of templates corresponding to different partial match errors of the target pixel, wherein each of the plurality of templates includes an enhancement pixel;

compare a pixel-bit subset of the window with a prediction-bit subset of at least one of the plurality of templates for a partial match; and

responsive to the partial match being found with a given template, substitute the enhancement pixel of the given template for the target pixel.

2. The computer system of claim 1, further comprising a rendering device and wherein the circuit is further operable to provide a corrected image including one or more enhancement pixels for reproduction on the rendering device.

3. The computer system of claim 1, wherein the circuit is further operable to compare the pixel-bit subset of the window with the prediction-bit subsets of at least two of the plurality of templates.

4. The computer system of claim 1, wherein the circuit is further operable to respond to the partial match with more than one template of the plurality of templates by applying a priority scheme to determine which template of the plurality of templates for which the partial match was found is used for substituting the target pixel with the enhancement pixel.

5. The computer system of claim 1, wherein the pixel-bit subset of the window comprises pixels from a same line as the target pixel as well as pixels from at least one line above and at least one line below the target pixel.

6. A computer system comprising:

a processor;

memory accessible by the processor; and

code stored in the memory, wherein the code is executable by the processor to perform operations comprising;

storing at least a portion of an image as pixels in the memory;

selecting a window including a plurality of adjacent pixels forming line segments of the image, wherein the window further includes a target pixel;

comparing a pixel-bit subset of the window as defined by a mask of a template with a prediction-bit subset as defined by a pattern of the template for a partial match, where the template is associated with an enhancement pixel;

assigning weights to each matched bit identified during the comparison;

multiplying each matched bit by its assigned weight pursuant to determining whether there is the partial match; and

responding to the partial match with the template by substituting the enhancement pixel of the template for the target pixel.

7. The computer system of claim 6, wherein the code is executable to perform operations comprising:

comparing a first prediction-bit subset of a first template to a first pixel-bit subset of the window, where the first template is associated with a first enhancement pixel; and

comparing a second prediction-bit subset of a second template to a second pixel-bit subset, where the second template is associated with a second enhancement pixel.

8. The computer system of claim 7, wherein the code is executable to perform operations comprising application of a priority scheme to determine which of the first or second enhancement pixels is substituted for the target pixel in response to the partial match with both the first and second templates.