Image processing apparatus
View Patent ↗An image processing apparatus includes first and second standard-deviation calculating circuits for calculating deviations σ 1 and σ 2 indicating a luminance bias of each pixel forming an input image. The deviation σ 1 is calculated by referring to an average luminance of first block images forming the input image, and the deviation σ 2 is calculated by referring to an average luminance of second block images forming the input image. A first correction-coefficient calculating circuit adjusts a correction coefficient K 1 based on the deviation σ 1 , and a second correction-coefficient calculating circuit adjusts a correction coefficient K 2 based on the deviation σ 2 . A Y correcting circuit corrects the luminance of each pixel forming the input image by referring to the correction coefficients K 1 and K 2 . A CPU determines an input-image-attribute including presence/absence of a face image of a person so as to change adjustment characteristics of the correction coefficients K 1 and K 2.
1. An image processing apparatus, comprising:
a bias degree calculator which calculates a bias degree of each luminance of a plurality of pixels forming an input image by referring to an average luminance of the input image;
a luminance corrector which corrects each luminance of the plurality of pixels forming the input image based on the bias degree calculated by said bias degree calculator;
a searcher which searches for a partial image representing a specific object from the input image; and
a luminance setting adjuster which adjusts a setting of said luminance corrector so that a characteristic for correcting a luminance of a contour portion of an object appeared on the input image is different depending on a search result of said searcher, the image processing apparatus further comprising:
a color corrector which corrects each color of the plurality of pixels forming the input image by referring to a luminance corrected by said luminance corrector; and
a color setting adjuster which adjusts a setting of said color corrector so that a characteristic for correcting a color is different depending on the search result of said searcher, wherein said color setting adjuster includes a first color characteristic setter which sets the correction characteristic of said color corrector to a first color characteristic corresponding to detection of said searcher, and a second color characteristic setter which sets the correction characteristic of said color corrector to a second color characteristic corresponding to non-detection of said searcher;
said first color characteristic is equivalent to a characteristic in which a chroma in a high luminance portion and/or a low luminance portion is inhibited and the chroma in a medium-luminance portion is increased, and said second color characteristic is equivalent to a characteristic in which the chroma of the low-luminance portion is inhibited and the chroma of the high-luminance portion is increased.
2. The image processing apparatus according to claim 1 , wherein said luminance setting adjuster includes a first luminance characteristic setter which sets the correction characteristic of said luminance corrector to a first luminance characteristic corresponding to detection of said searcher; and a second luminance characteristic setter which sets the correction characteristic of said luminance corrector to a second luminance characteristic corresponding to non-detection of said searcher.
3. The image processing apparatus according to claim 1 , further comprising a holder which holds a dictionary image equivalent to the specific object, wherein said searcher searches for the partial image with reference to the dictionary image held by said holder.
4. An image processing apparatus, comprising:
a bias degree calculator which calculates a bias degree of each luminance of a plurality of pixels forming an input image by referring to an average luminance of the input image;
a luminance corrector which corrects each luminance of the plurality of pixels forming the input image based on the bias degree calculated by said bias degree calculator;
a searcher which searches for a partial image representing a specific object from the input image; and
a luminance setting adjuster which adjusts a setting of said luminance corrector so that a characteristic for correcting a luminance of a contour portion of an object appeared on the input image is different depending on a search result of said searcher, the image processing apparatus,
a first average-luminance calculator which calculates a first average luminance equivalent to an average luminance of the input image for each first block having a first size; and
a second average-luminance calculator which calculates a second average luminance equivalent to an average luminance of the input image for each second block having a second size larger than the first size, wherein said bias degree calculator includes a first bias-degree calculator which calculates a first bias degree equivalent to a bias degree for the first average luminance and a second bias-degree calculator which calculates a second bias degree equivalent to a bias degree for the second average luminance,
wherein said luminance corrector includes a first coefficient adjustor which adjusts a first correction coefficient based on the first bias degree, a second coefficient adjustor which adjusts a second correction coefficient based on the second bias degree, and an arithmetic processor which performs an arithmetic process on the first average luminance and the second average luminance by referring to the first correction coefficient and the second correction coefficient, and said luminance setting adjuster includes an adjustment characteristic changer which changes adjustment characteristics of said first coefficient adjustor and said second coefficient adjustor.
5. The image processing apparatus according to claim 4 , wherein said arithmetic processor includes a block bias degree calculator which calculates a block bias degree equivalent to a bias degree of the first average luminance for the second average luminance, and a weighter which weights the block bias degree by referring to the first correction coefficient.
6. The image processing apparatus according to claim 4 , wherein said luminance corrector includes an adder which adds an offset, and said luminance setting adjuster includes an offset changer which changes a magnitude of the offset.
7. The image processing apparatus according to claim 4 , wherein said luminance corrector further includes: a gamma-correction-amount outputter which outputs a gamma correction amount corresponding to each of the plurality of pixels forming the input image; and a modifier which modifies the gamma correction amount outputted by said gamma-correction-amount outputter by referring to an arithmetic operation result of said arithmetic processor.