Method and Apparatus for Removing Noise from a Digital Image
AssigneeAdobe Systems Incorporated
InventorDennis G. Nicholson
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Abstract
One embodiment of the present invention provides a system that removes noise from an image. During operation, the system first identifies blobs in the image, wherein a blob is a set of contiguous pixels which possibly represents a character or a portion of a character in the image. Next, the system analyzes the blobs to dynamically determine a “noise threshold” for the blobs. The system then removes blobs from the image which are below the noise threshold.
Claims21
-21. (canceled)
A method for removing noise from an image, comprising:
- receiving the image;
- analyzing the image, comprising:
- identifying a text region within the image;
- identifying one or more key characters within the text region, wherein a key character is a character or a portion of a character;
- locating a plurality of blobs within the image, wherein a blob is a cluster of adjacent pixels which possibly represent a character or part of a character within the image;
- computing a noise threshold based on a size of the one or more key characters within the text region, wherein blobs of the plurality of blobs that are smaller than said noise threshold are likely to be noise;
- and
- removing from the image one or more of the plurality of blobs which are smaller than said noise threshold.
A computer-readable storage medium storing program instructions that when executed by a computer cause the computer to perform:
- receiving the image;
- analyzing the image, comprising:
- identifying a text region within the image;
- identifying one or more key characters within the text region, wherein a key character is a character or a portion of a character;
- locating a plurality of blobs within the image, wherein a blob is a cluster of adjacent pixels which possibly represent a character or part of a character within the image;
- computing a noise threshold based on a size of the one or more key characters within the text region, wherein blobs of the plurality of blobs that are smaller than said noise threshold are likely to be noise;
- and
- removing from the image one or more of the plurality of blobs which are smaller than said noise threshold.
A system that removes noise from an image, comprising:
- a processor;
- and
- memory storing program instructions executable by the processor to perform:
- receiving the image;
- analyzing the image, comprising:
- identifying a text region within the image;
- identifying one or more key characters within the text region, wherein a key character is a character or a portion of a character;
- locating a plurality of blobs within the image, wherein a blob is a cluster of adjacent pixels which possibly represent a character or part of a character within the image;
- computing a noise threshold based on a size of the one or more key characters within the text region, wherein blobs of the plurality of blobs that are smaller than said noise threshold are likely to be noise;
- and
- removing from the image one or more of the plurality of blobs which are smaller than said noise threshold.
Dependencies are inferred from the claim text.