Colour fidelity for textile materials captured by still digital camera

Globalization of textile and clothing industry demands high speed and precise communication of product information. Comparing with other kinds of information, colour is most difficult to communicate with satisfactory accuracy. To over this difficulty, advanced digital colour communication technology must be adopted, which provides a digital framework of using device independent colorimetric values defined by CIE (International Commission on Illumination). Input device such as digital camera is an important part of the framework. In order to provide satisfactory mean of digitizing colour information, appropriate techniques of characterization should be carefully carried out. This study developed an image capturing system using digital camera for textiles materials. The textile images captured are pixel-by-pixel colour databases which can be transferred to monitor display and output devices such as printer. As the RGB values captured by digital camera were device-dependent values, which are inaccurate for colour communication between devices, the RGB values were converted to device-independent values, such as CIE colorimetric attribute. The device related colour space was transformed to CIE standard colour space by a polynomial method using the least-square fitting technique. Macbeth ColorChecker Chart and IT8 colour target were used to develop the characterization model. Standard BCRA ceramic tiles and textile fabric samples made from different materials such as cotton, polyester, etc. were used to test the performance of characterization and the camera metamerism.