Further Developing ´Canon Unified High-Image-Quality Color´ for Input and Output Devices
Color Management Technology
Since input and output devices have their own distinct characteristics, including differences in the color gamut that each device is capable of reproducing, colors appearing on displays or in printout are inconsistent with the colors of the original input image.
To achieve high image quality and consistent color-reproduction performance on a variety of input and output devices, Canon has established color development guidelines. This technology, called Canon Unified High-Quality Color, has been incorporated into various Canon products.
In recent years, Canon developed this technology to create "Kyuanos," a high-accuracy color management system (CMS). This system enables accurate color matching with reduced color difference by taking into consideration factors such as lighting conditions or print media, which have a large impact on how colors appear.
Differences in reproducible color gamut between devices
Kyuanos high-accuracy color management system (CMS)
Color matching requires a device profile (color development data) for each combination of both input/output device and paper media. Conventional technology demands a tremendous investment of time and effort for the creation and tuning of profiles. With Kyuanos, however, profiles can be set up automatically, making it easy to achieve high-accuracy color matching that satisfies professional requirements.
With recent technological advancements, the color reproduction range of input/output devices has expanded, making it difficult to reproduce colors correctly using the conventional 8-bit and sRGB standard color space. Kyuanos offers an extended color space and a 16-bit format that allows for maximum input and output performance without color space restrictions. This enables the reproduction of exceptionally vivid colors with rich gradation.
Another advantage of Kyuanos is its capability to numerically convert colors based on human perception, lighting characteristics, and the color reproduction characteristics of devices. Based on this data, both colorimetric data and psychological color perception of humans are taken into
account to accurately correct and reproduce colors, even under different lighting conditions.
For example, precise color matching is achieved by taking into account the color difference that humans perceive under different lighting, such as the fluorescent lights used in offices and incandescent lamps in homes, which can significantly affect the way colors appear. Kyuanos has already been incorporated into Canon's large-format printers, and will also be introduced in various Canon products.
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Without Kyuanos:
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With correction for ambient light by Kyuanos:
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Controlling Color Appearance with Kyuanos
Color optimization for different devices and panel testing
The optimal method for color reproduction varies depending on the content and intended use of the image. Canon classifies color-reproduction methods into three modes-digital photo color, business color, and high-end color-each with its own development guidelines for both input and output devices.
Optimal Color Development by Color Reproduction Mode
The digital-photo-color mode emphasizes photographs, while the business-color mode particularly supports the reproduction of text and graphics. The high-end-color mode is used when accurate color reproduction is of critical importance.
With the digital-photo-color and business-color modes, the way people view colors is affected by individual preference. Canon applied its wealth of expertise in image evaluation, measurement, and image processing technology to assign quantitative values to preferred colors and enable the creation of color targets based on those values.
To determine these optimal values, Canon conducted large-scale panel tests in Japan, North America, and Europe to gain user insight. A wide range of participants, from the general public to designers and professional photographers, provided subjective assessments of multiple image samples viewed under different conditions. Through these tests, the researchers succeeded in establishing product-independent preferences for top-quality color images. These results are now reflected in the development of all Canon digital imaging products.
Integrated image development environment for high image quality for all Canon products
Canon established the Color Technical Center to conduct R&D, design and evaluation activities targeting high-image-quality color imaging. The Center, which aims to establish next-generation color technologies, provides an integrated image development environment supporting comprehensive development flows linked with production and sales.
Integrated Image Development Environment for Canon Unified High-Quality Colors
[1] Measurement and calibration
Maintaining high image quality requires accurate and stable color measuring instruments. Canon has established its own color-measurement and assessment standards and created measurement environments in each business group to enable high-precision measuring.
Canon's Color Technical Center formulates strict traceability (operational history and tracking) standards for measuring instruments (colorimeters in particular) within each product group. It also manages all measuring instruments for each division, from development to quality assessment, using master measuring instruments.
[2] Simulation
At the Color Technical Center, Canon performs high-precision measurements of colors, and conducts high-precision image simulations on a supercomputer for input and output devices. The supercomputer is used to conduct simulations designed to automatically select optimal colors from the approximately 280 trillion possible color combinations that can be obtained from ink used in inkjet printers.
[3] Design
Achieving consistent colors across all Canon products requires the creation and company-wide sharing of tools for the efficient development and assessment of colors in accordance with the company's guidelines. Using data based on 3-D technology and human perception characteristics, Canon developed its own high-precision distortion-eliminating algorithm that transcends the limits of human visual perception.
As a result of using the algorithm to create a 3-D Color CAD design tool, the company achieved a significant reduction in the time required to develop color tables for each product.
[4] Evaluation
Canon has established a benchmarking environment that provides matrix evaluations of both its own input and output products and those of other manufacturers. Targeting the achievement of high image quality, this benchmarking environment supports the objective assessment of color performance not only between Canon products, but also between Canon products and those of other manufacturers.
[5] Image information database
Canon has accumulated an extensive variety of reusable development and evaluation data in its image information database. Additionally, development-support tools and assessment tools are accessible via a network from any development facility throughout the company, creating an environment that enables optimal development activities regardless of location.
