Image data processing method and apparatus, storage medium product, and program product

• US 7,079,152 B2
• Filed: 09/09/2002
• Issued: 07/18/2006
• Est. Priority Date: 09/18/2001
• Status: Expired due to Fees

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Iguchi, Ryosuke, Yamazoe, Manabu, Torigoe, Makoto, Fujita, Takashi, Akiyama, Yuji
• Primary Examiner(s): Bella, Matthew C.
• Assistant Examiner(s): CUNNINGHAM, GREGORY F
• Application Number:
  US10/236,981
• Publication Number:
  US 20030052895A1
• Time in Patent Office: 1,408 Days
• Field of Search: 345/589, 345/590, 345/600, 345/601, 345/602, 345/604, 345/FOR.172
• US Class Current: 345/589
• CPC Class Codes: H04N 1/6005 with luminance or chrominance signals, e.g. LC1C2, HSL or YUV
• CPC Class Codes: H04N 1/6058 Reduction of colour to a range of reproducible colours, e.g. to ink- reproducible colour gamut

Abstract

When printing image data obtained by an input device, the present invention is intended to effectively utilize the color reproduction area of the printer. An image data processing method of the present invention comprises the steps of scale-down shifting a first color space point outside a maximum color reproduction area of an output unit to a second color space point within the maximum color reproduction area of the output unit; computing an amount of shift by which the first color space point is shifted to the second color space point; converting the second color space point to a third color space point within a color reproduction area smaller than the maximum color reproduction area of the output unit; and outputting an image to the output unit using image data obtained by scale-up shifting the third color space point to a fourth color space point within the maximum color reproduction area of the output unit based on the computed shift amount.

Claims

1. An image data processing method comprising the steps of:

determining whether image data has a value outside a standard color space;

converting the image data using a first conversion table when the image data is within the standard color space, and reproducible by a printer, and the said converting also using a second conversion table when the image data is outside the standard color space and reproducible by the printer; and

outputting the image data converted in said converting step for printing by the printer.

3. An image data processing method according to claim 1,

wherein said standard color space is an sRGB color space.

4. An image data processing method according to claim 1,

wherein said standard color space is a standard color space for an operating system used in a personal computer.

5. An image data processing method according to claim 1,

wherein the image data is input from a digital still camera or a digital camcorder.

2. An image data processing apparatus comprising:

means for determining whether image data has a value outside a standard color space;

a first conversion table adapted for use when the image data is within the standard color space and is reproducible by a printer;

a second conversion table adapted for use when the image data is outside the standard color space and is reproducible by the printer;

means for converting the image data using one of said first conversion table and said second conversion table; and

means for outputting the image data converted by said converting means for printing by the printer.

6. An image data processing apparatus according to claim 2,

wherein said standard color space is an sRGB color space.

7. An image data processing apparatus according to claim 2,

wherein said standard color space is a standard color space for an operating system used in a personal computer.

8. An image data processing apparatus according to claim 2,

wherein the image data is input from a digital still camera or a digital camcorder.