Method, apparatus, and computer program product for processing an image to reduce image deterioration
AssigneeRicoh Company, Ltd.
InventorAyumu Hashimoto
Life of this patent
Estimating the term…
Abstract
A method for processing an image includes: detecting and outputting an attributed of each pixel of input image data; performing a filtering process in which smoothing is performed on the input image data; detecting an edge amount being N value (where N>2) information from the data subjected to the smoothing; removing a chromatic color in a first removal amount according to the detected edge amount from all of the pixels; and removing a chromatic color in a second removal amount according to the detected edge amount from the pixel that has been determined to have a text attribute and an achromatic attribute at the detecting, wherein the second removal amount is determined on the basis of a discrete M value (where M>2) corresponding to the edge amount.
Claims8
A method for processing an image comprising:
- detecting and outputting an attribute of each pixel of input image data;
- performing a filtering process in which smoothing is performed on the input image data;
- detecting an edge amount being N value (where N>2) information from the input image data subjected to the smoothing;
- removing a chromatic color in a first removal amount according to the detected edge amount from all pixels;
- removing the chromatic color in a second removal amount according to the detected edge amount from a pixel that has been determined to have a text attribute and an achromatic attribute at the detecting the attribute;
- and
- determining a signal-to-noise (S/N) ratio of the input image data, wherein
- the second removal amount is determined based on a discrete M value (where M>2) corresponding to the edge amount,
- the filtering process includes smoothing with a different smoothing filter for each attribute of the pixel using a result of detection at the detecting the attribute when the determined S/N ratio exceeds a first threshold, and
- the filtering process includes emphasizing with a different emphasizing filter for each attribute of the pixel using the result of the detection at the detecting the attribute when the determined S/N ratio is equal to or higher than a second threshold.
An apparatus for processing an image, comprising:
- a pixel-attribute determiner configured to detect an attribute of each pixel of input image data;
- a filter configured to perform smoothing on the input image data;
- an edge-amount detector configured to detect an edge amount being N-value (where N>2) information from the input image data subjected to the smoothing;
- and
- an under-color remover configured to perform a first under-color removal process in which a chromatic color is removed in a first removal amount according to the detected edge amount from all pixels, and a second under-color removal process in which the chromatic color is removed in a second removal amount according to the detected edge amount from a pixel that has been determined to have a text attribute and an achromatic attribute by the pixel-attribute determiner, wherein
- the second removal amount is determined based on a discrete M value (where M>2) corresponding to the edge amount
- the filter is configured to perform smoothing with a different smoothing filter for each attribute of the pixel using a result of detection by the pixel-attribute determiner when a determined S/N ratio of the input image data exceeds a first threshold, and
- the filter is configured to perform emphasizing with a different emphasizing filter for each attribute of the pixel using the result of the detection by the pixel-attribute determiner when the determined S/N ratio of the input image data is equal to or higher than a second threshold.
A computer program product for processing an image, comprising a non-transitory computer-readable medium storing a program that causes a computer to execute:
- detecting and outputting an attribute of each pixel of input image data;
- performing a filtering process in which smoothing is performed on the input image data;
- detecting an edge amount being N value (where N>2) information from the input image data subjected to the smoothing;
- removing a chromatic color in a first removal amount according to the detected edge amount from all pixels;
- removing the chromatic color in a second removal amount according to the detected edge amount from a pixel that has been determined to have a text attribute and an achromatic attribute at the detecting the attribute;
- and
- determining a signal-to-noise (S/N) ratio of the input image data, wherein
- the second removal amount is determined based on a discrete M value (where M>2) corresponding to the edge amount,
- the filtering process includes smoothing with a different smoothing filter for each attribute of the pixel using a result of detection at the detecting the attribute when the determined S/N ratio exceeds a first threshold, and
- the filtering process includes emphasizing with a different emphasizing filter for each attribute of the pixel using the result of the detection at the detecting the attribute when the determined S/N ratio is equal to or higher than a second threshold.
Dependencies are inferred from the claim text.