Interpolation processing apparatus and recording medium having interpolation processing program recorded therein

Claim 2

An interpolation processing apparatus comprising: an interpolation processing unit that performs interpolation processing on a color image expressed through a colorimetric system constituted of a predetermined plurality of color components to determine an interpolation quantity corresponding to a value representing a missing color component in each pixel; and a color composition identification unit that identifies a color component composition of the color image, said color component composition representing hue information of the color image, wherein: said interpolation processing unit is capable of performing a plurality of types of interpolation processing in correspondence to color component compositions of the color image, selects a type of interpolation processing corresponding to the color component composition identified by said color composition identification unit and performs the type of interpolation processing that has been selected on the color image.

Claim 3

An interpolation processing apparatus according to claim 1 , wherein: when said interpolation processing unit decides that the color image is a single-hue image based upon the color component composition identified by said color composition identification unit, said interpolation processing unit selects an interpolation processing that uses a value corresponding to a value of a color component of a pixel to undergo interpolation processing as an interpolation quantity for another color component in the pixel.

Claim 4

An interpolation processing apparatus according to claim 1 , wherein: when said interpolation processing unit decides that the color image is a single-hue image based upon the color component composition identified by said color composition identification unit, said interpolation processing unit selects an interpolation processing in which weighting factor as to a value of a color component of a pixel to undergo interpolation processing is increased and weighted addition is performed for the value of the color component in the pixel and a value of a color component of a pixel located near said pixel to determine an interpolation quantity for another color component in said pixel.

Claim 5

An interpolation processing apparatus according to claim 2 , wherein: said color composition identification unit divides the color image into a plurality of areas and identifies a color component composition for each area by calculating color averages each of which indicates an average value per pixel for one of the color components within each area and calculating differences among the color averages of the color components; and said interpolation processing unit decides that the color image is a single-hue image when the differences among the color averages of the color components in all the areas are within predetermined ranges respectively.

Claim 6

An interpolation processing apparatus according to claim 2 , wherein: said color composition identification unit divides the color image into a plurality of areas and identifies a color component composition for each area by calculating color averages each of which indicates an average value per pixel for one of the color components within each area and calculating ratios among the color averages of the color components; and said interpolation processing unit decides that the color image is a single-hue image when the ratios among the color averages of the color components in all the areas are within predetermined ranges respectively.

Claim 7

An interpolation processing apparatus according to claim 4 , wherein: differences among color averages of the color components in a specific area among said plurality of areas are used as reference values and said predetermined ranges are set centered around said reference values.

Claim 8

An interpolation processing apparatus according to claim 5 , wherein: ratios among color averages of the color components in a specific area among said plurality of areas are used as reference values and said predetermined ranges are set centered around said reference values.

Claim 9

An interpolation processing apparatus according to claim 3 , wherein: said color composition identification unit divides the color image into a plurality of areas and identifies a color component composition for each area by calculating color averages each of which indicates an average value per pixel for one of the color components within each area and calculating differences among the color averages of the color components; and said interpolation processing unit decides that the color image is a single-hue image when the differences among the color averages of the color components in all the areas are within predetermined ranges respectively.

Claim 10

An interpolation processing apparatus according to claim 3 , wherein: said color composition identification unit divides the color image into a plurality of areas and identifies a color component composition for each area by calculating color averages each of which indicates an average value per pixel for one of the color components within each area and calculating ratios among the color averages of the color components; and said interpolation processing unit decides that the color image is a single-hue image when the ratios among the color averages of the color components in all the areas are within predetermined ranges respectively.

Claim 11

An interpolation processing apparatus according to claim 8 , wherein: differences among color averages of the color components in a specific area among said plurality of areas are used as reference values and said predetermined ranges are set centered around said reference values.

Claim 12

An interpolation processing apparatus according to claim 9 , wherein: ratios among color averages of the color components in a specific area among said plurality of areas are used as reference values and said predetermined ranges are set centered around said reference values.

Claim 13

An interpolation processing apparatus according to claim 1 , wherein: when said interpolation processing unit decides that the color image is a gray image based upon the color component composition identified by said color composition identification unit, said interpolation processing unit selects an interpolation processing that uses a value corresponding a value of a color component of a pixel to undergo interpolation processing as interpolation quantity for another color component in the pixel.

Claim 14

An interpolation processing apparatus according to claim 12 , wherein: said color composition identification unit divides the color image into a plurality of areas and identifies a color component composition for each area by-calculating color averages each of which indicates an average value per pixel for one of the color components within each area and calculating differences among the color averages of the color components; and said interpolation processing unit decides that the color image is a gray image when the differences among the color averages of the color components in all the areas are within predetermined ranges respectively.

Claim 15

An interpolation processing apparatus according to claim 12 , wherein: said color composition identification unit divides the color image into a plurality of areas and identifies a color component composition for each area by calculating color averages each of which indicates an average value per pixel for one of the color components within each area and calculating ratios among the color averages of the color components; and said interpolation processing unit decides that the color image is a gray image when the ratios among the color averages of the color components in all the areas are within predetermined ranges respectively.

Claim 16

An interpolation processing apparatus according to claim 14 , wherein: said predetermined ranges are centered around a value 1.

Claim 17

A recording medium that records an interpolation processing program to be executed by a computer, said interpolation program comprising: a procedure in which a color component composition of a color image expressed through a colorimetric system constituted of a predetermined plurality of color components are identified, said color component composition representing hue information of the color image; a procedure in which one type of interpolation processing that corresponds to the color component composition that has been identified is selected from a plurality of types of interpolation processing corresponding to color component compositions of the color image; and a procedure in which the interpolation processing that has been selected is executed and an interpolation quantity corresponding to a value of a color component missing in each pixel is determined for the color image.

Claim 18

A recording medium that records an interpolation processing program to be executed by a computer, said interpolation program comprising: a procedure in which a color component composition of a color image expressed through a colorimetric system constituted of a predetermined plurality of color components are identified, said color component composition representing hue information of the color image; a procedure in which one type of interpolation processing that corresponds to the color component composition that has been identified is selected from a plurality of types of interpolation processing corresponding to color component compositions of the color image; and a procedure in which the interpolation processing that has been selected is executed and an interpolation quantity corresponding to a value of a color component missing in each pixel is determined for the color image.

Claim 19

An electronic camera comprising: an image-capturing device that has a plurality of pixels and generates an image by capturing an image of a subject; color filters that are provided in correspondence to a plurality of pixels of said image-capturing device and are constituted by adopting a colorimetric system constituted of a plurality of color components; an interpolation processing device that performs interpolation processing on a color image generated by said color filters and said image-capturing device to determine an interpolation quantity corresponding to a value of a missing color component in each pixel; and a color composition identification device that identifies a color component composition of the color image, said color component composition representing hue information of the color image, wherein: said interpolation processing device is capable of performing a plurality of types of interpolation processing in correspondence to color component compositions of the color image, selects a type of interpolation processing that corresponds to the color component composition identified by said color composition identification device and performs the type of interpolation processing that has been selected on the color image.

Claim 20

An electronic camera comprising: an image-capturing device that has a plurality of pixels and generates an image by capturing an image of a subject; color filters that are provided in correspondence to a plurality of pixels of said image-capturing device and are constituted by adopting a colorimetric system constituted of a plurality of color components; an interpolation processing device that performs interpolation processing on a color image generated by said color filters and said image-capturing device to determine an interpolation quantity corresponding to a value of a missing color component in each pixel; and a color composition identification device that identifies a color component composition of the color image, said color component composition representing hue information of the color image, wherein: said interpolation processing device is capable of performing a plurality of types of interpolation processing in correspondence to color component compositions of the color image, selects a type of interpolation processing that corresponds to the color component composition identified by said color composition identification device and performs the type of interpolation processing that has been selected on the color image.

Claim 21

An electronic camera according to claim 17 , wherein: when said interpolation processing device decides that the color image is either one of a single-hue image and a gray image based upon the color component composition identified by said color composition identification device, said interpolation processing device selects an interpolation processing that uses a value corresponding a value of a color component of a pixel to undergo interpolation processing as an interpolation quantity for another color component in the pixel.

Claim 22

An interpolation processing apparatus comprising: an interpolation processing unit that performs interpolation processing on a color image expressed through a colorimetric system constituted of a predetermined plurality of color components to determine an interpolation quantity corresponding to a value representing a missing color component in each pixel; and a color composition identification unit that identifies a color component composition of the color image, said color component composition representing one of at least a single-hue image, a color image other than the single-hue image, a gray image and a color image other than the gray image, wherein: said interpolation processing unit is capable of performing a plurality of types of interpolation processing in correspondence to color component compositions of the color image, selects a type of interpolation processing corresponding to the color component composition identified by said color composition identification unit and performs the type of interpolation processing that has been selected on the color image.

Claim 23

An interpolation processing apparatus comprising: an interpolation processing unit that performs interpolation processing on a color image expressed through a colorimetric system constituted of a predetermined plurality of color components to determine an interpolation quantity corresponding to a value representing a missing color component in each pixel; and a color composition identification unit that identifies a color component composition of the color image, said color component composition representing one of at least a single-hue image, a color image other than the single-hue image, a gray image and a color image other than the gray image, wherein: said interpolation processing unit is capable of performing a plurality of types of interpolation processing in correspondence to color component compositions of the color image, selects a type of interpolation processing corresponding to the color component composition identified by said color composition identification unit and performs the type of interpolation processing that has been selected on the color image.

Claim 24

An interpolation processing apparatus according to claim 3 , wherein said weighting factor is set to be larger than ½.