Using a Digital Camera for Measuring Viewing Parameters on Image Appearance
This study investigated the possibility of applying a characterised digital camera to quantify viewing parameters on image appearance under various surrounding conditions. Two methods were implemented to determine two viewing parameters: the adapting luminance level (LA) and the luminance factor of background (Yb). The measurements were conducted using a digital camera and a tele-spectroradiometer (TSR). After obtained the fundamental image information which derived from the camera characterisation model, low-pass filtered images were used to investigate the influence of different parts of an adapting field on viewing parameters and the degree of contribution of different parts to the perceived image match under various viewing conditions. Note that the luminance values for the adapting field were obtained from low-pass images of the luminance channel. To evaluate these methods, a digital colour chart was presented on a CRT display. The image of this viewing environment was captured using the same digital camera under three viewing conditions. The tristimulus values, XYZ, of each colours were transformed to CIECAM021-4 J, aM, bM coordinates using the viewing parameters obtained from two methods. CIECAM02 △EJab was calculated between the standard colours measured using a TSR and the predictions from the two methods. The psychophysical experiments were also conducted to evaluate these methods. The results were quite different when under dark and under average surround conditions. It can be seen that applied the captured image plus the surround, agreed well with measurement and visual result under dim and average surround conditions; but performed unsatisfactory under dark surround condition.
Chenyang Fu M Ronnier Luo
Department of Colour Science, University of Leeds United Kingdom
国际会议
The 31st International Congress on Imaging Science(第31届国际影像科学大会 ICIS2010)
北京
英文
604-607
2010-05-12（万方平台首次上网日期，不代表论文的发表时间）