Shape from shading (SfS) and stereo are two fundamentally different strategies for imagebased 3-D reconstruction. While approaches for SfS infer the depth solely from pixel intensities, methods for stereo are based on finding correspondences across images. In this paper we propose a joint variational method that combines the advantages of both strategies. By integrating recent stereo and SfS mo...

A new quaternion based method is presented which recovers albedo for shape reconstruction from three color images for three directions of white light source. In the conventional approaches, red, green and blue components are considered separately so there is a loss of information. The albedo maps recovered are not accurate enough to recover shape. Property of quaternion is that a color can then...

We isolate and quantify the two factors controlling Northern Hemisphere springtime snow albedo feedback in transient climate change based on scenario runs of 17 climate models used in the IPCC 4th Assessment. The first factor is the dependence of planetary albedo on surface albedo, representing the atmosphere’s attenuation effect on surface albedo anomalies. It is potentially a major source of ...

[1] Radiative transfer modeling of the reduction of snow albedo by black carbon (BC) requires experimental verification. In natural snow the albedo reduction is at most a few percent, and even with accurate measurements, attribution is ambiguous because snow albedo depends on other variables. In this experiment, artificial snowpacks are made by freezing of water droplets produced by a snowmakin...

The shortwave broadband MODIS albedo has higher uncertainties over snow-covered land and at large Solar Zenith Angle (SZA). We have documented a systematic negative bias for SZA>55-60° in Greenland. This study uses in situ data from the Greenland Climate Network (GC-Net) to characterize and empirically correct the MODIS snow albedo (MCD43C) bias at large SZA and thereby remediate the implied bi...

SOUTH POLE OF MARS. Alejandro Soto, Xin Guo, and Mark I. Richardson, Caltech, M/C 150-21, Pasadena, CA 91125. [email protected], [email protected], [email protected] Introduction: A perennial CO2 ice cap has long been observed near the south pole of Mars. The retention of a CO2 ice cap results from the surface energy balance of the latent heat, solar radiation, surface emission, and subsurfa...

Narrowband-to-broadband conversion is a critical procedure for mapping land-surface broadband albedo using multi-spectral narrowband remote-sensing observations. Due to the significant difference in optical characteristics between soil and vegetation, NTB conversion is influenced by the variation in vegetation coverage on different surface types. To reduce this influence, this paper applies an ...

Linear mixtures of materials in a scene often occur because the resolution of a sensor is relatively coarse, resulting in pixels containing patches of different materials within them. This phenomenon causes nonoverlapping areal mixing and can be modeled by a linear mixture model. More complex phenomena, such as the multiple scattering in mixtures of vegetation, soils, granular, and microscopic ...