Image forming apparatus

Abstract

An image forming apparatus includes a reading unit that reads image data, a drawing data storage unit that stores object data comprising the read image data so as to allow the stored object data to be distinguished between a vector object and a raster object, a vector gray determination unit that determines whether each of stored vector objects is formed of an achromatic color, a raster gray determination unit that determines whether each of stored raster objects is formed of an achromatic color, and an output data creation unit that converts the stored object data into multicolor when the stored object data includes a chromatic color and converts the stored object data into monochrome when the stored object data is formed only of achromatic colors.

1 . An image forming apparatus, comprising:
 a data reading unit that reads image data;   a drawing data storage unit that stores object data comprising the read image data so as to allow the stored object data to be distinguished between a vector object and a raster object;   a vector gray determination unit that determines whether or not each of stored vector objects is formed of an achromatic color;   a raster gray determination unit that determines whether or not each of stored raster objects is formed of an achromatic color; and   an output data creation unit that converts the stored object data into multicolor when the stored object data includes a chromatic color, and converts the stored object data into monochrome when the stored object data is formed only of achromatic colors.   
     
     
         2 . The image forming apparatus according to  claim 1 , wherein the data reading unit reads the image data on a page by page basis. 
     
     
         3 . The image forming apparatus according to  claim 1 , wherein when one or more vector objects among the stored vector objects are not formed of an achromatic color, the output data creation unit outputs the vector object by converting the one or more vector objects into multicolor. 
     
     
         4 . The image forming apparatus according to  claim 1 , wherein:
 color values of the image data are formed of RGB values; and   when the RGB value of the vector object satisfies “R=G=B”, the vector gray determination unit determines that the vector object is in the achromatic color.   
     
     
         5 . The image forming apparatus according to  claim 1 , wherein:
 the output data creation unit outputs the stored object data by converting the stored object data into one of a CMY value and a CMYK value; and   when all of the stored object data are formed of achromatic colors, the output data creation unit performs a color output in black.   
     
     
         6 . The image forming apparatus according to  claim 1 , comprising:
 a vector gray flag setting unit that sets a vector gray flag when all of the stored vector objects are formed of achromatic colors; and   a raster gray flag setting unit that sets a raster gray flag when all of the stored raster objects are formed of achromatic colors, wherein:   the output data creation unit performs a color output based on multicolor when one of the vector gray flag and the raster gray flag is not set; and   the output data creation unit performs a color output based on monochrome when the vector gray flag and the raster gray flag are both set.   
     
     
         7 . An image forming apparatus, comprising:
 a data reading unit that reads image data;   a band split unit that divides the read image data into a plurality of bands allowing each of object data comprising the image data to be distinguished between a vector object and a raster object;   an overlap band detection unit that identifies a band having an overlap between the vector object and the raster object;   a specified color value acquisition unit that determines a color value of a vector object existing in the overlap band;   an overlap band representative color detection unit that determines a representative color of a raster object existing in the overlap band;   an output color value calculation unit that calculates an output color value corresponding to the color value of the vector object and an output color value corresponding to the representative color of the raster object; and   a visibility determination unit that determines a visibility of an overlapping portion based on a comparison of output color values.   
     
     
         8 . The image forming apparatus according to  claim 7 , wherein the data reading unit reads the image data on a page by page basis. 
     
     
         9 . The image forming apparatus according to  claim 7 , wherein the overlap band representative color detection unit determines the representative color of the raster object based on pixels within the overlap band. 
     
     
         10 . The image forming apparatus according to  claim 7 , wherein the visibility determination unit compares the output color value of the vector object and the output color value of the raster object, and determines a visibility of an overlapping portion based on the comparison. 
     
     
         11 . The image forming apparatus according to  claim 7 , wherein the visibility determination unit calculates a color difference between the output color value of the vector object and the output color value of the raster object that are calculated by the output color value calculation unit, and when the color difference is 0 (zero) or within a predetermined threshold value range, notifies of an alert. 
     
     
         12 . The image forming apparatus according to  claim 7 , comprising:
 a first color conversion table for converting the color value of the vector object into a output color value; and   a second color conversion table for converting the representative color of the raster object into a output color value, wherein:   the output color value calculation unit calculates the output color value corresponding to the color value of the vector object using the first color conversion table; and   the output color value calculation unit calculates the output color value corresponding to the representative color of the raster object detected by the overlap band representative color detection unit using the second color conversion table.   
     
     
         13 . The image forming apparatus according to  claim 7 , wherein the visibility determination unit calculates a color difference between the output color value of the vector object and the output color value of the raster object that are calculated by the output color value calculation unit, and when the color difference is 0 (zero) or within a predetermined threshold value range, outputs color values after performing an addition or subtraction of a fixed value to/from one or plurality of the output color value of the vector object and the output color value of the raster object. 
     
     
         14 . The image forming apparatus according to  claim 7 , wherein the overlap band representative color detection unit extracts and counts color values of all of the pixels within the overlap band and sets a color value whose count value is the largest as a representative color. 
     
     
         15 . The image forming apparatus according to  claim 7 , wherein the overlap band representative color detection unit extracts and counts color values of pixels of an overlapping portion between the vector object and the raster object, and sets a color value whose count value is largest as a representative color.