Simulated leaf canopy shading with polymethyl methacrylate(PMMA) filter.

Is shading a linear filter?

The decomposition of an input image into its materialdependent “intrinsic” properties and its light-dependent shading properties is useful for many computer vision tasks such as image segmentation, object recognition, and geometric inference. For example, image segmentation and edge detection can be performed by grouping sets of pixels by reflectance values; object recognition will be more robu...

Estimating Corn Leaf Chlorophyll Concentration from Leaf and Canopy Reflectance

Farmers must balance the competing goals of supplying contributions of background reflectance, while spectral vegetation indices that combined reflectances of near-infrared adequate N for their crops while minimizing N losses to the environment. To characterize the spatial variability of N and other visible bands (MCARI and NIR/Green) were responsive to both leaf chlorophyll concentrations and ...

Leaf wetness within a lily canopy

A wetness duration experiment was carried out within a lily field situated adjacent to coastal dunes in the Netherlands. A within-canopy model was applied to simulate leaf wetness in three layers, with equal leaf area indices, within the canopy. This simulation model is an extension of an existing model. It appeared that in most cases leaf wetness started in the uppermost layer followed by the ...

Water stress of sugarbeet as related to leaf and canopy temperatures and to leaf Water content

Highlight and Shading Invariant Color Image Segmentation Using Simulated Annealing

Color constancy in color image segmentation is an important research issue. In this paper we develop a framework, based on the Dichromatic Re ection Model for asserting the color highlight and shading invariance, and based on a Markov Random Field approach for segmentation. A given RGB image is transformed into a R'G'B' space to remove any highlight components, and only the vector-angle compone...