Shadow removal

So far, we have mostly assumed that objects are directly illuminated by a light source. But what about shadows In real world scenes, one object may cast a shadow on another object. In this case, the area outside the shadow is directly illuminated, while the shadow area is diffusely illuminated by light that is reflected from other objects in the scene. Thus, for a natural scene containing shadows, we have at least two different illuminants, the light source and the illuminant of the shadow area. In Chapter 7, we have already seen a number of algorithms that can cope with an illuminant that varies smoothly over the image. A shadow, however, may have a sharp boundary. We discuss an algorithm for shadow removal in this chapter. 

Uses Flattening reducer (i.e., reduces highlight detail more than shadows) removes developer stains. 

Ions are also used to initiate secondary ion mass spectrometry (SIMS) [ ], as described in section BI.25.3. In SIMS, the ions sputtered from the surface are measured with a mass spectrometer. SIMS provides an accurate measure of the surface composition with extremely good sensitivity. SIMS can be collected in the static mode in which the surface is only minimally disrupted, or in the dynamic mode in which material is removed so that the composition can be detemiined as a fiinction of depth below the surface. SIMS has also been used along with a shadow and blocking cone analysis as a probe of surface structure [70]. 

FIG. 13 TEM micrograph of a hollow composite nanoparticle/polymer capsule dried on a carbon grid. The hollow composite capsule was obtained after removal of the ME core from Si02/PDAD-MAC-coated ME particles by treatment with hydrochloric acid. The shadowing seen is a result of collapse and overlapping of the hollow capsule upon drying. (From Ref. 110.)... 

Data have been analyzed from a multivariate point of view. In this way the cooperative effects of the different materials is studied and the characteristics of each sensor are easily compared with those of the other sensors. PLS was used as a regression method for calculating the capability of the set of sensors to discriminate between the volatile compounds. Volatile compounds were checked at different concentrations in order to evaluate the response of sensors in a wide concentration range. Nevertheless, the concentration variation tends to shadow the reaction of sensors with analytes, since the sensor response contains both qualitative (sensor analyte interaction) and quantitative (analyte concentration) information. In order to remove the quantitative information, data have been normalized using the linear normalization discussed in section 3. 

The development of a positive only occupies a few seconds, and it must be stopped as soon as there Is tbe faintest indication of the details In the shadows. The plate should then be well washed to remove all traces of iron, and the picture fixed with a liquid composed of ... 

A near white surface finish corresponds to Swedish standard Sa 2-1/2 or BS4232 second quality. This finish is defined as one from which is removed all oil, grease, dirt, mill scale, rust, corrosion products, oxides remaining coatings, except for a very light shadows of light streak discolouration. At least 95% of the surface shall have the appearance of a white metal surface finish and the remainder shall be limited to light discolouration. 

A commercial blasted surface finish corresponds to Swedish Standard Sa2 third quality. The finish is defined as one from which oil, grease, dirt, rust-scale and foreign matter have been completely removed from the surface, except for slight shadows, streaks or... 

While looking down the stock face for shadowed areas, if these are found, they need to be rolled down while bleeding the air with a needle or cut out to remove all trapped air and patched. 

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