The properties of planar ice crystals settling horizontally have been investigated using a vertically-pointing Doppler lidar. Strong specular reflections were observed from their oriented basal facets, identified by comparison with a second lidar pointing 4◦ from zenith. Analysis of 17 months of continuous high-resolution observations reveal that these pristine crystals are frequently observed ...

Microscopic hyperspectral imaging technology is a potential non-destructive and non-contact method for colour measurement of micrometre-sized textile fibres. However, specularity on the fibre surface can distort accurate information affect accuracy measurement. This paper proposed specular-constrained sparse approximation (SCSA) specular-diffuse reflection separation from images wool First, spe...

We estimate surface normal maps of an object from either its diffuse or specular reflectance using four spherical gradient illumination patterns. In contrast to traditional photometric stereo, the spherical patterns allow normals to be estimated simultaneously from any number of viewpoints. We present two polarized lighting techniques that allow the diffuse and specular normal maps of an object...

PURPOSE To investigate the correlation between the clinical pictures and the specular microscopic findings in patients with iridocorneal endothelial (ICE) syndrome. METHODS The records of 15 patients with ICE syndrome who presented at the National Taiwan University Hospital between 1993 and 1996 were examined. The medical history, clinical pictures of the cornea, iris and anterior chamber ang...

We address two quality issues in endoscopy videos originating from: (a) Colour Channel Misalignment: In current endoscope systems, the colour channel images are most commonly acquired sequentially at different time instances. Whenever the camera moves significantly between acquisition instances, the colour channels get misaligned. This misalignment degrades the quality of the video due to the a...

AIMS To report the appearances of iridocorneal endothelial (ICE) syndrome from real time, white light confocal microscopy. METHODS Three consecutive patients, each with ICE syndrome, were examined prospectively. Corneal specular and confocal microscopic examinations were performed in all three patients. In the first patient, a penetrating keratoplasty was performed and the cornea was examined...

The perception of surface gloss depends on specular highlights but little is understood about how the visual system distinguishes specular highlights from other luminance maxima generated by variations in pigmentation or illumination. It has been argued that diffuse shading gradients provide information for identifying specular highlights. Specular highlights typically share the orientation of ...