Method, apparatus, and recording medium for image correction

Abstract

Color reproducibility of a proof print agrees with color reproducibility of a print generated at a laboratory. Image data obtained by a user with a digital camera are printed by a printer to generate a proof print. The proof print is read by reading means in a laboratory and scanned image data are obtained. The scanned image data are converted into a Lab color space by first conversion means, and converted scanned image data are generated. A relationship between data values of original image data and the converted scanned image data is calculated as a look-up table by calculation means. Second conversion means converts the original image data based on the look-up table, and obtains converted original image data. Third conversion means converts the converted original image data into print image data, and printing means generates a print by printing the print image data.

1 . An image correction method comprising: 
 obtaining scanned image data and ID information by photoelectrically reading a proof print obtained from original image data representing an original image, the ID information added inseparably to the proof print for identifying the original image;    reading equivalent original image data representing an equivalent original image corresponding to the obtained ID information from storage means storing a plurality of original image data sets in relation to ID information;    calculating a relationship between data values of the scanned image data and the equivalent original image data as a color correspondence relationship;    carrying out a color conversion for obtaining print image data by converting the equivalent original image data into a color space for printing based on the color correspondence relationship; and    obtaining a print based on the print image data.    
     
     
         2 . An image correction apparatus comprising: 
 image reading means for obtaining scanned image data and ID information by photoelectrically reading a proof print obtained from original image data representing an original image, the ID information added inseparably to the proof print for identifying the original image;    storage means for storing a plurality of original image data sets related to ID information;    reading means for reading equivalent original image data representing an equivalent original image corresponding to the obtained ID information from the storage means;    calculation means for calculating a relationship between data values of the scanned image data and the equivalent original image data as a color correspondence relationship;    color conversion means for obtaining print image data by converting the equivalant original image data into a color space for printing based on the color correspondence relationship; and    printing means for obtaining a print based on the print image data.    
     
     
         3 . A computer-readable recording medium storing a program to cause a computer to execute an image correction method, the program comprising the procedures of: 
 obtaining scanned image data and ID information by photoelectrically reading a proof print generated from original image data representing an original image, the ID information added inseparably to the proof print for identifying the original image;    reading equivalent original image data representing an equivalent original image corresponding to the obtained ID information from storage means storing a plurality of original image data sets in relation to ID information;    calculating a relationship between data values of the scanned image data and the equivalent original image data as a color correspondence relationship;    carrying out a color conversion for obtaining print image data by converting the equivalent original image data into a color space for printing based on the color correspondence relationship; and    obtaining a print based on the print image data.    
     
     
         4 . An image correction method comprising: 
 obtaining scanned image data and ID information by photoelectrically reading a proof print obtained from original image data representing an original image, the ID information added inseparably to the proof print for identifying the original image;    carrying out a first color conversion for obtaining converted scanned image data by converting the scanned image data into a common color space corresponding to color perception;    reading equivalent original image data representing an equivalent original image corresponding to the obtained ID information from storage means storing a plurality of original image data sets in relation to ID information;    calculating a relationship between data values of the converted scanned image data and the equivalent original image data as a color correspondence relationship;    carrying out a second color conversion for obtaining converted original image data by converting the equivalent original image data into the common color space based on the color correspondence relationship;    carrying out a third color conversion for obtaining print image data by converting the converted original image data from the common color space into a color space for printing; and    obtaining a print based on the print image data.    
     
     
         5 . An image correction method as defined in  claim 4 , the step of carrying out the first color conversion further comprising the steps of: 
 averaging and sampling the scanned image data in each of areas having a predetermined range; and    obtaining the converted scanned image data by converting the sampled scanned image data into the common color space, and the step of calculating further comprising the steps of:    averaging and sampling the equivalent original image data in each of the areas having the predetermined range; and    calculating, as the color correspondence relationship, a relationship between data values of a converted scanned image represented by the converted scanned image data and a sampled original image represented by the sampled equivalent original image data, at positions corresponding to each other in the sampled original image and in the converted scanned image.    
     
     
         6 . An image correction method as defined in  claim 4  or  5 , wherein the color correspondence relationship is calculated as a look-up table.  
     
     
         7 . An image correction apparatus comprising: 
 image reading means for obtaining scanned image data and ID information by photoelectrically reading a proof print obtained from original image data representing an original image, the ID information added inseparably to the proof print for identifying the original image;    storage means for storing a plurality of original image data sets related to ID information;    first color conversion means for obtaining converted scanned image data by converting the scanned image data into a common color space corresponding to color perception;    reading means for reading equivalent original image data representing an equivalent original image corresponding to the obtained ID information from the storage means;    calculation means for calculating a relationship between data values of the converted scanned image data and the equivalent original image data as a color correspondence relationship;    second color conversion means for obtaining converted original image data by converting the equivalent original image data into the common color space based on the color correspondence relationship;    third color conversion means for obtaining print image data by converting the converted original image data from the common color space into a color space for printing; and    printing means for obtaining a print based on the print image data.    
     
     
         8 . An image correction apparatus as defined in  claim 7 , wherein 
 the first color conversion means obtains the converted scanned image data by averaging and sampling the scanned image data in each of areas having a predetermined range and by converting the sampled scanned image data into the common color space, and    the calculation means averages and samples the equivalent original image data in each of the areas having the predetermined range, and calculates the color correspondence relationship as a relationship between data values of a converted scanned image represented by the converted scanned image data and a sampled original image represented by the sampled original image data, at positions corresponding to each other in the sampled original image and in the converted scanned image.    
     
     
         9 . An image correction apparatus as defined in  claim 7  or  8 , wherein the calculation means calculates the color correspondence relationship as a look-up table.  
     
     
         10 . A computer-readable recording medium storing a program to cause a computer to execute an image correction method, the program comprising the procedures of: 
 obtaining scanned image data and ID information by photoelectrically reading a proof print generated from original image data representing an original image, the ID information added inseparably to the proof print for identifying the original image;    carrying out a first color conversion for obtaining converted scanned image data by converting the scanned image data into a common color space corresponding to color perception;    reading equivalent original image data representing an equivalent original image corresponding to the obtained ID information from storage means storing a plurality of original image data sets in relation to ID information;    calculating a relationship between data values of the converted scanned image data and the equivalent original image data as a color correspondence relationship;    carrying out a second color conversion for obtaining converted original image data by converting the equivalent original image data into the common color space based on the color correspondence relationship;    carrying out a third color conversion for obtaining print image data by converting the converted original image data from the common color space into a color space for printing; and    obtaining a print based on the print image data.    
     
     
         11 . A computer-readable recording medium as defined in  claim 10 , the procedure of carrying out the first color conversion further comprising the procedures of: 
 averaging and sampling the scanned image data in each of areas having a predetermined range; and    obtaining the converted scanned image data by converting the sampled scanned image data into the common color space, and the procedure of calculating further comprising the procedures of:    averaging and sampling the equivalent original image data in each of the areas having the predetermined range; and    calculating, as the color correspondence relationship, a relationship between data values of a converted scanned image represented by the converted scanned image data and a sampled original image represented by the sampled equivalent original image data, at positions corresponding to each other in the sampled original image and in the converted scanned image.    
     
     
         12 . A computer-readable recording medium as defined in  claim 10  or  11 , the procedure of calculating being the procedure of calculating the color correspondence relationship as a look-up table.