title: Rapid material appearance acquisition using consumer hardware.
abstract: A photo-realistic representation of material appearance can be achieved by means of bidirectional texture function (BTF) capturing a material's appearance for varying illumination, viewing directions, and spatial pixel coordinates. BTF captures many non-local effects in material structure such as inter-reflections, occlusions, shadowing, or scattering. The acquisition of BTF data is usually time and resource-intensive due to the high dimensionality of BTF data. This results in expensive, complex measurement setups and/or excessively long measurement times. We propose an approximate BTF acquisition setup based on a simple, affordable mechanical gantry containing a consumer camera and two LED lights. It captures a very limited subset of material surface images by shooting several video sequences. A psychophysical study comparing captured and reconstructed data with the reference BTFs of seven tested materials revealed that results of our method show a promising visual quality. Speed of the setup has been demonstrated on measurement of human skin and measurement and modeling of a glue dessication time-varying process. As it allows for fast, inexpensive, acquisition of approximate BTFs, this method can be beneficial to visualization applications demanding less accuracy, where BTF utilization has previously been limited.
authors.affiliation: Institute of Information Theory and Automation of the ASCR, Prague 182 08 , Czech Republic. filipj@utia.cas.cz.
authors.forename: Jiří
authors.initials: J
authors.lastname: Filip
authors.affiliation: Institute of Information Theory and Automation of the ASCR, Prague 182 08 , Czech Republic. vavra@utia.cas.cz.
authors.forename: Radomír
authors.initials: R
authors.lastname: Vávra
authors.affiliation: Institute of Information Theory and Automation of the ASCR, Prague 182 08 , Czech Republic. krupimik@utia.cas.cz.
authors.forename: Mikuláš
authors.initials: M
authors.lastname: Krupička
mesh_terms: D006801:Humans; D007089:Image Enhancement; D008027:Light; D011601:Psychophysics / Q000295:instrumentation* / Q000379:methods