| Modeling of plant appearance color is an important topic both in agronomicresearch and computer graphics field, in which plant leaf received wideattention as the most important plant organ. This dissertation focus on the colorof cucumber leaves based on several physiological and ecological factors,mainly including three contents as follows:A method for visual simulating leaf color based on the relative content ofchlorophyll was proposed. The mathematical model between cucumber leafcolor components and chlorophyll relative content was established according toimages acquisited from real field and measuring chlorophyll relative content(SPAD) of the cucumber leaf in normal growth state continuously. The renderingfor the spatial distribution of apparent color of cucumber leaf was realized bycombining with a black and white pigment distribution texture which was agrayscale image before being preprocessed. The result showed that the methodproposed in this paper can achieved pleasing realistic rendering results.A method for rendering cucumber leaf color based on the concentration ofchlorophyll a, b and carotene was proposed. The mathematical model betweencucumber leaf color components and different pigments concentration wasestablished based on images and pigments concentration acquisited fromcucumber leaf. The rendering of cucumber leaf color based on the knowledge ofphysiology and physical senses was achieved by combining the algorithm ofphysical lighting model. It achieved pleasing realistic rendering results.Three methods for rendering cucumber leaf color in three differentdeficiency conditions. The mathematical model between color value of everypixel in the color picture and the gray value of the same pixel in the grayscalewas established by matching the real values. With the NormalMap technologywe realized the cucumber leaf apparent color distribution at different degrees ofnitrogen deficiency state; based on the mathematical model and the BumpMaptechnology, we realized the cucumber leaf apparent color distribution atdifferent degrees of potassium deficiency state; In addition, with the Noise andMixing technology,we achieved the cucumber leaf apparent color distribution atdifferent degrees of phosphorus deficiency state. |
