Gray levels

It allows to save the radiographic film in computer for an eventual digital processing. In our case welded joints radiographic films are digitized in 256 gray levels. 

In order to be able to respond fully to the study of the spatial and angular relations between the back-ground of the image and the defects, we opted for the Co-Occurrence Matrix using spatial gray level dependence method. 

What we see is that Mathematica has plotted the functions, fitted them with surfaces, placed a grid on the fitted surfaces and enhanced them with gray-level shadowing. All of this was done by routine operation in a default mode, that is, with a minimum of input from us. Here too we could spend time further enhancing these graphs, but instead we shall move on to the next subject. 

Images were acquired with 5-s exposure time after having fixed the focus. The total intensity of fluorescence was estimated by calculations the integral of the gray-level histogram. 

To obtain color images with a HCCD camera, filter wheels will be used, in which each filter will be chosen specifically for one fluorescent label, in emission and in excitation. For CL or BL work, one filter wheel is sufficient. For fluorescence, two are necessary (see, for instance, in Fig. 3 the positioning of the filter wheels in the optical path). If, for instance, a three-color experiment is performed, an image will be acquired for each label with the adapted filter(s). The three gray-level images are sequentially acquired. They will then be colored ... 

Fig. 1. An ultrathin section of an untreated fresh protoplast with 4% uranyl acetate and 0.4% lead citrate. A line profile of gray level (below) was taken along the double-headed arrow through the Golgi cistemae (G) and the endoplasmic reticulum (ER). (From ref. 40.)...

Mean value of peak contrast (MP) can be expressed as total variation/ number of peaks, where total variation is the sum of gray level difference between the peaks and the valleys in a line profile. The difference of the MP between the membranes of the Golgi cistemae and of the ER is expressed by the ratio V G/VER, where VG is the MP of the Golgi apparatus, and VER the MP of the ER. As shown in Table 1, the ratio VG/VER was about 1.2 times higher than the control, confirming that the differ-... 

The issue of power consumption of an OLED display panel changing with the information content has not been well addressed in the OLED field. For AMLCD display panel, the power consumption is almost independent of the information content. For an AMOLED or an AMPLED panel, the power consumption is directly proportional to the number of pixels lighting up. For each display pixel, the power consumption is nearly proportional to the level of brightness (gray level). Thus, AMOLED display only consumes the power necessary, without any waste. This effect is similar to the concept of Pay-Per-View developed in cable and satellite TV industries. Two direct consequences of the Pay-Per-View effect are ... 

The SPRi reader was from Toyobo (Japan). The interactions pro-dnce changes in the reflectivity indexes near the gold surface, which result in the changes of the reflectivity recorded by a CCD camera as gray-level contrasts. 

The thresholding-based segmentation is the simplest segmentation method but it works well if the objects have uniform gray level clearly distinguishable from the background that must have a different but uniform gray level with respect to the objects. 

After segmentation, it is possible to measure the features of interest for each of the individuated objects. The measurable features regard size (area, perimeter, length, width), shape (circularity, eccentricity, compactness, extent, and so on), color, and texture (smoothness, coarseness, graininess) (Du and Sun, 2004). Texture, in particular, is evaluated on the base of the gray level variation within the object (Aguilera and Stanley, 1999). 

Fig. 14.1. The first reported active-matrix display with an organic semiconductor. The display contains 64 by 64 pixels and is driven by 4096 polymer TFT, with solution processed PTV as the semiconductor. An image containing 256 gray levels is shown. The display is refreshed at 50 Hz.

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