Abstract: An electronic endoscope apparatus includes a connection unit for selectively connecting a plurality of machine types of electronic endoscopes which use different color information obtainment methods and a plurality of replacement tables which are provided for the plurality of machine types of electronic endoscopes respectively, and each of which stores a correspondence between values representing colors which can be obtained by each of the electronic endoscopes by photographing an observation object and values representing the true colors of the observation object. The electronic endoscope apparatus distinguishes the machine type of the electronic endoscope and replaces the values of obtained colors by using the replacement table for the distinguished machine type. Further, the electronic endoscope apparatus stores setting information for each purpose of examination, and further performs image processing, based on selected setting information, on the image of which the values of the colors have been replaced.

Abstract: An image obtained by an electronic endoscope apparatus is changed to an image that is appropriate for observation with suppressed halation and fewer dark areas. Halation detection means detects halation of a predetermined level or higher in an image represented by a signal obtained by an imaging device, based on the signal. Light amount adjustment means decreases an amount of light emitted from illumination means to cause the halation to become a predetermined level or lower. Luminance conversion means processes the signal so as to generate a luminance conversion image wherein only a dark area having a predetermined luminance or lower in the image due to the decrease in the amount of the light is changed to have a higher luminance.

Abstract: An electronic endoscope apparatus includes a scope unit in which a color filter is provided. The scope unit further includes a filter information storage means for storing filter information showing the kind of the color filter provided in the scope unit. Further, a plurality of kinds of scope units, each of which has filter information showing a different kind of color filter from each other, can be selectively connected. The filter information stored in the filter storage means of the connected scope unit is obtained. Then, color space correction processing is performed, based on the filter information, on color image signals output from the plurality of kinds of scope units so that each of signals for display, produced from the color image signals, represents the same point in color space.

Abstract: An electronic endoscope apparatus includes an imaging element and a signal processing unit. The imaging element obtains an image of an observation object, and outputs an image signal of the observation object. The signal processing unit alternately repeats obtainment of a partial image signal using a part of a light receiving area of the imaging element and obtainment of a partial image signal using the remaining part of the light receiving area. The signal processing unit also obtains a whole image signal corresponding to an image of the observation object using a partial image signal obtained in the n-th (n is a natural number) obtainment and a partial image signal obtained in the (n+1)th obtainment. Further, a partial component of the n-th partial image signal is extracted by an extraction unit, and the extracted partial component is added to the (n+1)th partial image signal.

Abstract: A color chart that enables exact color adjustments without being influenced by distortion or peripheral light loss is provided. The color chart has a plurality of colored regions each being of a different color, separated by line segments that radiate outward from a predetermined point. A plurality of achromatic colored regions are provided among the plurality of colored regions at predetermined intervals.

Abstract: An adjustment amount of a brightness level is determined for each pixel of an image based on the value of each pixel of a luminance distribution image which represents the distribution of luminance of the image. A portion contributing to adjustment of brightness and a portion contributing to adjustment of saturation are determined for each pixel of the image so that the sum thereof is equal to the adjustment amount of the brightness level. Then, an adjustment value of saturation, which is obtained by weighting the value of each pixel in the image based on the portion contributing to saturation, and an adjustment value of brightness, which is obtained by weighting the value of each pixel in the luminance distribution image, which corresponds to each pixel of the image, based on the portion contributing to brightness are added to the value of each pixel of the image.

Abstract: An image correction method comprising the steps of: specifying a region including the face of one person in an image of people displayed in a screen of image display means in response to an input from an operator; extracting a correction target region including at least the face of the person in the image, based on information on at least one of hue, saturation, lightness, and a position of an outline of the specified region; setting a degree of correction to be carried out on each position in the correction target region in such a manner that the degree of correction becomes lower from the inside of the correction target region to the outside thereof near a boundary of the correction target region; and correcting at least one of hue, saturation and lightness in the correction target region based on the degree of correction.

Abstract: The sharpness of an image obtained by an endoscope is adjusted. A sharpness enhancement amount is determined for each pixel based on the value of each pixel which forms a luminance distribution image. Further, a portion contributing to adjustment of brightness and a portion contributing to adjustment of saturation in the sharpness enhancement amount are determined for each pixel of the image so that the sum thereof is equal to the sharpness enhancement amount. Then, an adjustment value of saturation, which is obtained by weighting the value of each pixel of the image based on the portion contributing to saturation, and an adjustment value of brightness, which is obtained by weighting the value of each pixel of the luminance distribution image, which corresponds to each pixel of the image, based on the portion contributing to brightness, are added to the value of each pixel of the image.

Abstract: A color chart that enables exact color adjustments without being influenced by distortion or peripheral light loss is provided. The color chart has a plurality of colored regions each being of a different color, separated by line segments that radiate outward from a predetermined point. A plurality of achromatic colored regions are provided among the plurality of colored regions at predetermined intervals.

Abstract: An image correction method comprising the steps of: specifying a region including the face of one person in an image of people displayed in a screen of image display means in response to an input from an operator; extracting a correction target region including at least the face of the person in the image, based on information on at least one of hue, saturation, lightness, and a position of an outline of the specified region; setting a degree of correction to be carried out on each position in the correction target region in such a manner that the degree of correction becomes lower from the inside of the correction target region to the outside thereof near a boundary of the correction target region; and correcting at least one of hue, saturation and lightness in the correction target region based on the degree of correction.

Abstract: When an image obtained by an electronic endoscope apparatus is recorded, the image is recorded in a state where whether or not the image has been subjected to image processing can be judged with certainty. Recording image selection means selects either an original image without the image processing by image processing means or a processed image having been subjected to the image processing, as the image to be recorded by image recording means. Image type information generation means generates image type information representing whether the image selected by the recording image selection means is the original image or the processed image, and the image recording means records the selected image in relation to the image type information in response to operation by an operator using operation means.

Abstract: An electronic endoscope apparatus includes a connection unit for selectively connecting a plurality of machine types of electronic endoscopes which use different color information obtainment methods and a plurality of replacement tables which are provided for the plurality of machine types of electronic endoscopes respectively, and each of which stores a correspondence between values representing colors which canoe obtained by each of the electronic endoscopes by photographing an observation object and values representing the true colors of the observation object. The electronic endoscope apparatus distinguishes the machine type of the electronic endoscope and replaces the values of obtained colors by using the replacement table for the distinguished machine type. Further, the electronic endoscope apparatus stores setting information for each purpose of examination, and further performs image processing, based on selected setting information, on the image of which the values of the colors have been replaced.

Abstract: The sharpness of an image obtained by an endoscope is adjusted. A sharpness enhancement amount is determined for each pixel based on the value of each pixel which forms a luminance distribution image. Further, a portion contributing to adjustment of brightness and a portion contributing to adjustment of saturation in the sharpness enhancement amount are determined for each pixel of the image so that the sum thereof is equal to the sharpness enhancement amount. Then, an adjustment value of saturation, which is obtained by weighting the value of each pixel of the image based on the portion contributing to saturation, and an adjustment value of brightness, which is obtained by weighting the value of each pixel of the luminance distribution image, which corresponds to each pixel of the image, based on the portion contributing to brightness, are added to the value of each pixel of the image.

Abstract: An adjustment amount of a brightness level is determined for each pixel of an image based on the value of each pixel of a luminance distribution image which represents the distribution of luminance of the image. A portion contributing to adjustment of brightness and a portion contributing to adjustment of saturation are determined for each pixel of the image so that the sum thereof is equal to the adjustment amount of the brightness level. Then, an adjustment value of saturation, which is obtained by weighting the value of each pixel in the image based on the portion contributing to saturation, and an adjustment value of brightness, which is obtained by weighting the value of each pixel in the luminance distribution image, which corresponds to each pixel of the image, based on the portion contributing to brightness are added to the value of each pixel of the image.

Abstract: A replacement table for each purpose of examination is stored in an electronic endoscope apparatus in advance. The replacement table stores a correspondence between the value of color which can be obtained by photographing an observation object with an electronic endoscope and the value of color which is defined so that a hue in a range of color which is necessary for diagnosis is wider than a hue in a range of color which is not necessary for diagnosis. The electronic endoscope apparatus produces an image for a selected examination purpose by separately replacing the value of the color of each pixel which forms the image obtained by the electronic endoscope by using a correspondence stored in a replacement table for a single examination purpose specified by input instruction data.

Abstract: An image obtained by an electronic endoscope apparatus is changed to an image that is appropriate for observation with suppressed halation and fewer dark areas. Halation detection means detects halation of a predetermined level or higher in an image represented by a signal obtained by an imaging device, based on the signal. Light amount adjustment means decreases an amount of light emitted from illumination means to cause the halation to become a predetermined level or lower. Luminance conversion means processes the signal so as to generate a luminance conversion image wherein only a dark area having a predetermined luminance or lower in the image due to the decrease in the amount of the light is changed to have a higher luminance.

Abstract: An electronic endoscope apparatus includes an imaging element and a signal processing unit. The imaging element obtains an image of an observation object, and outputs an image signal of the observation object. The signal processing unit alternately repeats obtainment of a partial image signal using a part of a light receiving area of the imaging element and obtainment of a partial image signal using the remaining part of the light receiving area. The signal processing unit also obtains a whole image signal corresponding to an image of the observation object using a partial image signal obtained in the n-th (n is a natural number) obtainment and a partial image signal obtained in the (n+1) th obtainment. Further, a partial component of the n-th partial image signal is extracted by an extraction unit, and the extracted partial component is added to the (n+1) th partial image signal.

Abstract: An electronic endoscope apparatus includes a scope unit in which a color filter is provided. The scope unit further includes a filter information storage means for storing filter information showing the kind of the color filter provided in the scope unit. Further, a plurality of kinds of scope units, each of which has filter information showing a different kind of color filter from each other, can be selectively connected. The filter information stored in the filter storage means of the connected scope unit is obtained. Then, color space correction processing is performed, based on the filter information, on color image signals output from the plurality of kinds of scope units so that each of signals for display, produced from the color image signals, represents the same point in color space.

Abstract: The image defect detecting method detects, from image data obtained by reading photoelectrically an original, image defect candidates of an image to be reproduced by the image data which are due to damage of the original and foreign matter sticking to the original, or further foreign matter sticking to a reading system for reading the original, or foreign matter sticking to an image pick-up system for shooting a subject, and removes the image defect candidates in accordance with a density at which the image defect candidates are present, such that the image defect candidates present in a place where the density exceeds a predetermined state are removed and the image defect candidates which are not removed are regarded as image defects of the image to be reproduced by the image data.