Phytec eGrabber-4plus, Руководство по оборудованию

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eGrabber-4plus
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PHYTEC Meßtechnik GmbH 2004 L-608e_4
The color depth of the green channel is twice of the
two other channels. The RGB16-format corresponds
to the color system of graphic cards with 65.535
colors.
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RGB15: The division corresponds to the RGB16-
system, except that all color channels have the same
color depth (each 5-bit=32 levels). Therefore we yield
32.818 colors. Altogether only 15-bits are necessary,
so that the upper bit of a word is a stuffing bit and has
the value 0 (see Figure 52).
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YCrCb: In this format we find gray values and color information
separately. The parameter Y describes the brightness of the pixel
(grey value) and the parameter (Cr,Cb) provides the color
information. (Cr,Cb) can be considered as a vector of the
chromatic circle. The tone of the color corresponds to the angle of
the pointer, the saturation is presented by the absolute value of the
vector. This format is applied for graphic cards with
YcrCb-systems with separate processing of brightness and color
value - which is very compact for the storage of images in
memories.
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YUY2: This format corresponds to the format YCrCb
4:2:2. In one double word the information of two
pixels is found. Y0 and Y1 is the information for the
brightness of two adjacent pixels, Cb0 and Cr0
presents the color information of the first pixel, which
is used for both pixels. The color information of the
second pixel is not used.
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BtYUV : corresponds to YCrCb 4:1:1. Four pixels
share one color information. The arrangement of the
information in the memory is shown in Figure 52.
Three double words are logically combined to one unit
and contain the information for eight pixels. This is
the value for the brightness for each pixel (Y0..Y7)
and the color information of the first (Cb0/Cr0) and
fifth pixel (Cb4/Cr4).