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This article presents a measurement method for integrated three-dimensional shape and multispectral color measurement with the use of a single detector for data acquisition. Its implementation comprises a shape measurement system using structured light projection combined with a custom developed multispectral camera. Both devices are controlled by dedicated software which enables the estimation of spectral reflection in every point registered on the surface of the measured object. The main application of this research is the digitization of cultural heritage objects for storage, visualization, and copying purposes. Examples of measurement results are presented as well as discussion of measurement uncertainty and directions of further research. INTRODUCTIONIn an age where information systems are rapidly being developed with the advent of the internet and the formation of an information society, there is a growing need for a digital remote access to historical objects of cultural significance. The still growing computational power of personal computers (PCs) offers a new approach to preserve, measure, and visualize monuments.Moreover, it is very important for art conservators to be able to monitor the state of artifacts under varying environmental conditions, for example, monitoring deterioration due to atmospheric factors. A series of measurements taken over a period of time would allow them to estimate the optimal conditions for the storage and exhibition of the artifacts in order to preserve them as much as possible. There are also new methods of displaying cultural heritage artifacts through virtual museums, accessible via the Internet, which show precise reproductions and allow people to visit famous places in virtual reality.However, in order to use information technology to digitize items of cultural significance, it is very important to cooperate closely with art conservators and art historians and use their knowledge to raise the quality of the said digitization results. It benefits both scientists and artists because the former gain professional guidance on the applications of their research and the latter receive new interesting methods

Creating accurate three-dimensional (3D) digitalized models of cultural heritage objects requires that information about surface geometry be integrated with measurements of other material properties like color and reflectance. Up until now, these measurements have been performed in laboratories using manually integrated (subjective) data analyses. We describe an out-of-laboratory bidirectional reflectance distribution function (BRDF) and 3D shape measurement system that implements shape and BRDF measurement in a single setup with BRDF uncertainty evaluation. The setup aligns spatial data with the angular reflectance distribution, yielding a better estimation of the surface's reflective properties by integrating these two modality measurements into one setup using a single detector. This approach provides a better picture of an object's intrinsic material features, which in turn produces a higher-quality digitalized model reconstruction. Furthermore, this system simplifies the data processing by combining structured light projection and photometric stereo. The results of our method of data analysis describe the diffusive and specular attributes corresponding to every measured geometric point and can be used to render intricate 3D models in an arbitrarily illuminated scene.

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