The Natural Vision Project, established 1999 by the Telecommunications Advancement. Organization of Japan, aims to enable high-fidelity natural colour ...
AIC Colour 05 - 10th Congress of the International Colour Association
Natural Vision XML Database H. Kanazawa a , M. Yamaguchi a ,b , H. Haneishi a ,c , and N. Ohyama a , d a Natural Vision Research Center,NICT of Japan b Imaging Science and Engineering Lab., Tokyo Institute of Technology c Department of Information and Image Sciences, Chiba University d Frontier Collaborative Research Center, Tokyo Institute of Technology ABSTRACT To achieve high-fidelity colour reproduction, many different types of data such as camera characteristics, illumination, and display characteristics are required. We designed an XML schema that provides a core solution to natural vision content management. In addition, we developed an XML-based natural vision content management system. 1. INTRODUCTION The Natural Vision Project, established 1999 by the Telecommunications Advancement Organization of Japan, aims to enable high-fidelity natural colour reproduction in visual telecommunication systems. To reproduce high-fidelity colour, research and development is focused on technologies for collecting, transmitting, storing, analysing, and outputting images based on spectrum information. Unifying these efforts, a natural vision image data file format was developed to exchange image data in research and development of multi-spectral image technology. To achieve high-fidelity colour reproduction, different types of information are required, such as camera, illumination, and display device characteristics. This information is original to each natural vision image file, and should be managed as important R&D data. Unfortunately, the natural vision file format does not allow for recording these data. Therefore, users usually end up writing these data on scratch pads and storing them manually. As the contents increase, so too does the labour and time needed to manage them properly. In fact, these data are often lost, making reprocessing of colour conversion, analysis, and output impossible We think that the Extensible Markup Language (XML), a meta-language recommended by the World Wide Web Consortium (W3C), can manage unified natural vision image data, including the above-mentioned information, because it has the following features. a. Because XML is a meta-language, i.e., "a language for making language", it can create a data description language. b. XML is a markup language that uses character strings to describe data altogether, and because the document structure uses element enclosed with tags, meaning is expressed in characters that people can understand. c. XML is the Internet standard and can be used for data exchange between computers on the Internet. Furthermore, many tools are available for creating XML data, referencing and changing elements, etc. Moreover, many XML databases software (commercial and freeware) are also available, and developing an application system is easier than before. We have structured data related to image capture, colour estimation and conversion, and image display for natural vision objects. We have designed an XML schema, which provides a core solution to natural vision content management. In addition, we have built an XML-based natural vision content management system and tested its ability to store natural vision data. 2. NATURAL VISION DATA COMPOSITION Natural vision colour reproduction systems based on the spectrum have several functions. -Exact colour reproduction using spectrum (physical) information. -Colour reappearance under various illuminations.
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AIC Colour 05 - 10th Congress of the International Colour Association
-Display of conventionally unreproducible vivid colours using more than three primary colours. -Acquisition of quantitative information independent of illumination or devices. -Colour reproduction that considers the individual differences in human vision. In these functions, spectrum reflectance/radiation of a photographic subject plays the role of a base. To estimate spectrum reflectance/radiation, camera characteristic data, illumination, and statistical data of the photographic subject should be used. In addition, to reproduce an equivalent colour under a different environment or for a different person, the colour is converted using rendering illumination and colour matching functions. The characteristic data of display and observation illumination are also needed to display the exact colour. Natural Vision image data is of two types: still and video. For still images, all colour reproduction processing and related data belong to the picture. However, because colour reproduction data may differ among frames, videos are divided into two or more segments and colour reproduction data is attached to each segment (Fig. 1). time/ frame segment 1 sub segment 1.1
sub segment 1.2 NVData 1,1
NVData 1 NVData 1,2
sub segment 1,1,1 NVData 1,3,1
Figure 1: Video with natural vision data.
Natural vision colour is reproduced using three processes: NvisionInput, NvisionConversion, and NvisionOutput. The processes and related data are structured as shown in Fig. 2.
N visionInput
N vision
N visionIm age
N visionC olor
N visionO utput
N visionC onversion
InputSignalCompensation SpectralEstimation
OutputColorConversion OutputSignalConversion ColorConversion
InputDeviceData InputIllumination ObjectData
ColorConversionData RenderingIllumination
OutputDeviceData ObservingIllumination
Figure 2: Structure of natural vision data.
(a) NvisionInput Objective The input is mainly a variety of camera characteristic data for image corrections and illumination data and object statistical data for spectral reflectance estimation. (b) NvisionConversion Objective
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AIC Colour 05 - 10th Congress of the International Colour Association
The colour conversion objective consists of a variety of colour conversion data (spectral reflectance estimation matrices, rendering illumination data, colour matching functions, etc.) used for various colour space conversions. (c) NvisionOutput Objective The colour output information consists of display characteristic data and observational illumination data used to convert the image into various output images. 3. Natural Vision XML Schema We have developed an XML schema for natural vision video applications. Our Natural Vision XML schema is a metadata structure for describing and annotating Natural Vision Objective contents. A Natural Vision XML data begins with a root element, Nvision, followed by four elements, NvisionImage, NvisionInput, NvisionConversion, and NvisionOutput. The following is an example of an NVXML file. “image segment data” “camera characteristics data, illumination data, etc.” “rendering illumination data, color matching functions, etc.” “display characteristic data, observation illumination data, etc.” Each object has processing and data, and the relationship between processing and data is as follows it in the figure 3.
Data ID Data Id,
Figure 3: relationship between processing and data.
Similarly, a video consists of two or more segments, and in each segment, colour information is given by object IDs. We use this link method to manage the contents of Natural Vision image. 4. Testing
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AIC Colour 05 - 10th Congress of the International Colour Association
To make our Natural Vision XML Schema easy to use, we are scheduled to develop a graphical user interface with an XML editor, processing, and XML database interface (Fig. 4).
Graphical User Interface
XML editor
Natural Vision Processing
XML Database Interface
Natural Vision XML File
Input signal compensation Spectral Evaluation Color Conversion Output Signal Conversion
XML
Figure 4: Tools for Natural Vision XML Schema.
An XML database interface offers data manipulation functions, such as storing, updating, deleting, and searching. An XML editor offers functions such as grammar checking, inserting, deleting, and changing XML data, using our Natural Vision XML Schema. To test the rationality and usefulness of our Natural Vision XML Schema, we changed the case accumulation database system currently used to a Natural Vision XML database system, and store Natural Vision image data as XML data (only for still pictures). Development of the case accumulation database system for natural vision video is progressing in the current fiscal year. We think that Natural Vision XML Schema should be tested through mounting it to many Natural Vision systems. Furthermore, to make the Natural Vision XML Schema easier to use, it must be further developed and should offer various tools. References 1. M. Yamaguchi, “Natural vision spectrum-based natural color image reproduction system”, Electronic Imaging, SPIE Technical Group Newsletter. 2. H. Motomura et al, “Natural Vision Image Data File Format for Spectral-based Color Reproduction System”, The PICS Conference 2003, 278–284 (2003).
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