Image processing apparatus for discriminating image field of original document plural times and method therefor
AssigneeKabushiki Kaisha Toshiba
InventorsNaofumi Yamamoto, Haruko Kawakami, Gururaj Rao
Life of this patent
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Abstract
An image processing apparatus incorporating a field separating section for separating an original image into plural types of fields in response to a first image signal obtained at a rough density of the supplied original image, a characteristic value calculating section for calculating a characteristic value of the original image in response to a second image signal of the original image obtained at a density which is higher than the rough density, and a discrimination section for discriminating an image field of the original image in accordance with the characteristic value to correspond to the type of the field.
Claims12
An image processing apparatus comprising:
- first discrimination means for discriminating an original image into one of plural types of fields in response to a first image signal obtained at a first density of the original image;
- characteristic value calculating means for calculating a characteristic change value in density, an average density and chroma of the original image in response to a second image signal of the original image obtained at a second density which is higher than the first density;
- second discrimination means for selecting one of plural threshold values according to the type of field discriminated by the first discrimination means, and comparing the characteristic change value calculated by the characteristic value calculating means with the selected threshold value, so as to output a result of second discrimination;
- and
- image processing means for processing predetermined image processes corresponding to the result of second discrimination of the image field performed by the second discrimination means, on the second image signal.
An image processing method comprising the steps of:
- a first discrimination step for discriminating an original image into one of plural types of fields in response to a first image signal obtained at a first density of the supplied original image;
- a characteristic value calculating step for calculating a characteristic change value in density, average density, and chroma of the original image in response to a second image signal of the original image obtained at a second density which is higher than the first density;
- a second discrimination step for selecting one of plural threshold values according to the one of the plural types of fields discriminated by the first discrimination step, and comparing the characteristic change value calculated by the characteristic value calculating step with the selected threshold value, so as to output a result of second discrimination step;
- and
- an image processing step for processing predetermined image processes corresponding to the result of second discrimination step of the image field, on the second image signal.
Dependencies are inferred from the claim text.