A color data conversion apparatus and method. The color data conversion apparatus includes a K ratio calculator for outputting a K ratio that is calculated using entered color data; a K ratio adjuster for adjusting the calculated K ratio, which is output from the K ratio calculator, in reference to
A color data conversion apparatus and method. The color data conversion apparatus includes a K ratio calculator for outputting a K ratio that is calculated using entered color data; a K ratio adjuster for adjusting the calculated K ratio, which is output from the K ratio calculator, in reference to gamut boundary descriptors (GBDs) corresponding to a K ratio and outputting the adjusted K ratio as a final K ratio; and a CMY ratio calculator for calculating C, M, and Y ratios based on the final K ratio. When converting the entered color data to the CMYK data, the calculated K ratio can be adjusted to the K ratio printable by use of the K GBDs. Accordingly, the printing apparatus can substantially print according to the calculated K ratio and thus the degradation of the printing quality can be avoided.
대표청구항▼
What is claimed is: 1. A color data conversion apparatus comprising: a converter which converts entered color data to converted color data, the converted color data residing within a gamut defined by a total gamut boundary descriptor (GBD) that covers all gamuts defined by a plurality of K GBDs, an
What is claimed is: 1. A color data conversion apparatus comprising: a converter which converts entered color data to converted color data, the converted color data residing within a gamut defined by a total gamut boundary descriptor (GBD) that covers all gamuts defined by a plurality of K GBDs, and outputs the converted color data; a K ratio calculator which calculates a calculated K ratio based on the converted color data, wherein the K ratio calculator obtains an initial K ratio which is a K ratio corresponding to a lightness of the entered color data, and acquires the calculated K ratio using the initial K ratio; a K ratio adjuster which adjusts the calculated K ratio, based on the plurality of K GBDs, and outputs a final K ratio, wherein the K ratio adjuster determines if the entered color data resides within a GBD corresponding to a first K ratio and within a GBD corresponding to a second K ratio that is greater than the first K ratio, wherein the K ratio adjuster outputs the calculated K ratio as the final K ratio when the calculated K ratio is greater than the first K ratio and less than the second K ratio, wherein the K ratio adjuster outputs the first K ratio as the final K ratio when the calculated K ratio is less than the first K ratio, and wherein the K ratio adjuster outputs the second K ratio as the final K ratio when the calculated K ratio is greater than the second K ratio; and a CMY ratio calculator for calculating C, M, and Y ratios based on the final K ratio. 2. The color data conversion apparatus of claim 1, wherein the K ratio calculator acquires the calculated K ratio using the initial K ratio by using a graph produced by drawing a curve line corresponding to a certain rate of change from a point corresponding to a maximum K ratio to a point corresponding to a start lightness in a coordinate. 3. The color data conversion apparatus of claim 2, wherein the K ratio calculator calculates the K ratio by multiplying a generated output ratio and the initial K ratio using a function that has a chroma of the entered color data as an input variable. 4. The color data conversion apparatus of claim 3, wherein the function used by the K ratio calculator produces the generated output ratio which is less than a predetermined value when the input chroma resides outside a predetermined chroma range. 5. The color data conversion apparatus of claim 1, wherein the K ratio calculator calculates a first weight using a lightness of an input achromatic color and a start lightness, sets a maximum K ratio and a minimum K ratio to its upper limit K ratio and lower limit K ratio, respectively, and calculates the K ratio using the first weight, the upper limit K ratio and the lower limit K ratio, the input achromatic color has the same lightness as that of an input color corresponding to an input color data and the maximum K ratio and the minimum K ratio are determined among K ratios corresponding to the K GBDs that cover the input achromatic color. 6. The color data conversion apparatus of claim 5, wherein the K ratio calculator calculates the first weight (weight 1) and the K ratio by the following equations: K ratio=(1-weight 1)(lower limit K ratio)+(weight 1)(upper limit K ratio). 7. The color data conversion apparatus of claim 5, wherein the K ratio calculator, if the lightness of the input achromatic color is greater than the start lightness, sets the K ratio to '0'. 8. The color data conversion apparatus of claim 1, wherein the K ratio adjuster calculates a second weight using a chroma of an input color corresponding to an input color data, sets a maximum K ratio and a minimum K ratio to its upper limit K ratio and lower limit K ratio, respectively, and calculates the final K ratio using the second weight, the upper limit K ratio and the lower limit K ratio, the maximum K ratio and the minimum K ratio are determined among K ratios corresponding to the K GBDs that cover the input color and correspond to the K ratio equal to or less than the K ratio calculated by the K ratio calculator. 9. The color data conversion apparatus of claim 8, wherein the K ratio adjustor calculates the second weight (weight 2) and the final K ratio by the following equations: final K ratio=(1-weight 2)(lower limit K ratio)+(weight 2)(upper limit K ratio). 10. The color data conversion apparatus of claim 8, wherein the K ratio adjuster, if the chroma of the input color corresponding to the input color data is '0', sets the K ratio calculated by the K ratio calculator, to the final K ratio. 11. A color data conversion method comprising: converting entered color data to converted color data, the converted color data residing within a gamut defined by a total gamut boundary descriptor (GBD) that covers all gamuts defined by a plurality of K GBDs, and outputting the converted color data; calculating a K ratio based on the converted color data, wherein the calculating of the K ratio obtains an initial K ratio which is a K ratio corresponding to a lightness of the entered color data, and acquires the calculated K ration using the initial K ratio; adjusting the calculated K ratio based on the plurality of K gamut GBDs, and outputting a final K ratio, wherein the adjusting of the K ratio comprises determining if the entered color data resides within each of a GBD corresponding to a first K ratio and within a GBD corresponding to a second K ratio that is greater than the first K ratio, wherein the adjusting of the K ratio outputs the calculated K ratio as the final K ratio when the calculated K ratio is greater than the first K ratio and less than the second K ratio, wherein the adjusting of the K ratio outputs the first K ratio as the final K ratio when the calculated K ratio is less than the first K ratio, and wherein the adjusting of the K ratio outputs the second K ratio as the final K ratio when the calculated K ratio is greater than the second K ratio; and calculating C, M, and Y ratios based on the final K ratio. 12. The color data conversion method of claim 11, wherein the calculating of the K ratio acquires the calculated K ratio using the obtained initial K ratio using a graph produced by drawing a curve line corresponding to a certain rate of change from a point corresponding to a maximum K ratio to a point corresponding to a start lightness in a coordinate. 13. The color data conversion method of claim 12, wherein the K ratio is calculated by multiplying a generated output ratio and the initial K ratio using a function that has a chroma of the entered color data as an input variable. 14. The color data conversion method of claim 13, wherein the function used for the calculation of the K ratio produces the generated output ratio which is less than a predetermined value when the input chroma resides outside a predetermined chroma range. 15. The color data conversion method of claim 11, wherein the calculating of the K ratio comprises: calculating a first weight using a lightness of an input achromatic color and a start lightness, the input achromatic color having the same lightness as that of an input color corresponding to an input color data; setting a maximum K ratio and a minimum K ratio to its upper limit K ratio and lower limit K ratio, respectively, the maximum K ratio and the minimum K ratio determined among K ratios corresponding to the K GBDs that cover the input achromatic color; and calculating the K ratio using the first weight, the upper limit K ratio and the lower limit K ratio. 16. The color data conversion method of claim 15, wherein the calculating of the K ratio calculates the first weight (weight 1) and the K ratio by the following equations: K ratio=(1-weight 1)(lower limit K ratio)+(weight 1)(upper limit K ratio). 17. The color data conversion method of claim 15, wherein the calculating of the K ratio further comprises setting, if the lightness of the input achromatic color is greater than the start lightness, the K ratio to '0'. 18. The color data conversion method of claim 11, wherein the adjusting of the K ratio comprises: calculating a second weight using a chroma of an input color corresponding to an input color data; setting a maximum K ratio and a minimum K ratio to its upper limit K ratio and lower limit K ratio, respectively, the maximum K ratio and the minimum K ratio determined among K ratios corresponding to the K GBDs that cover the input color and correspond to the K ratio equal to or less than the K ratio calculated in the operation of the calculating of the K ratio; and calculating the final K ratio using the second weight, the upper limit K ratio and the lower limit K ratio. 19. The color data conversion method of claim 18, wherein the adjusting of the K ratio calculates the second weight (weight 2) and the final K ratio by the following equations: final K ratio=(1-weight 2)(lower limit K ratio)+(weight 2)(upper limit K ratio). 20. The color data conversion method of claim 18, wherein the adjusting of the K ratio further comprises setting, if the chroma of the input color corresponding to the input color data is '0', the K ratio calculated by the K ratio calculator, to the final K ratio.
연구과제 타임라인
LOADING...
LOADING...
LOADING...
LOADING...
LOADING...
이 특허에 인용된 특허 (47)
Chang,James Z.; Kress,William C., Black generation method for CMYK color printer using multiple lookup tables and interpolation.
Chang-Rack Yoon KR; Maeng-Sub Cho KR; Byoung-Ho Kang KR; Jin-Seo Kim KR; Hong-Kee Kim KR; Kyu-Seo Han KR, Color correction apparatus for minimizing metamerism of color scanner and method therefor.
Shimizu, Masayoshi; Mori, Masahiro; Suzuki, Shoji; Semba, Satoshi, Color data conversion method, color data conversion apparatus, storage medium, device driver and color conversion table.
Shimizu,Masayoshi; Mori,Masahiro; Suzuki,Shoji; Semba,Satoshi, Color data conversion method, color data conversion apparatus, storage medium, device driver and color conversion table.
Kita Shinji (Kanagawa JPX) Ogatsu Hitoshi (Kanagawa JPX) Murai Kazumasa (Kanagawa JPX), Color image processing method and apparatus capable of adjusting the UCR ratio.
Sasaki,Makoto; Ogatsu,Hitoshi; Ikegami,Hiroaki; Higashikata,Ryosuke, Color processing method, color processing device, storage medium, color processing program, and image forming apparatus.
Sasaki,Makoto; Ogatsu,Hitoshi; Ikegami,Hiroaki, Color processing method, storage medium, color processing apparatus, color transforming apparatus, and image forming apparatus.
Dalal Edul N. (Webster NY) Blaszak Sue E. (Penfield NY) Gruber Robert L. (Pittsford NY) Bertrand Jacques C. (Ontario NY) Ciccarelli Roger N. (Rochester NY), Environmentally friendly toner composition.
Ohkubo Akito,JPX, Method of converting data of a first colorimetric system to data of a second colorimetric system, including a mapping of out of boundary data.
※ AI-Helper는 부적절한 답변을 할 수 있습니다.