Phytec eGrabber-4plus, Руководство по оборудованию

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eGrabber-4plus
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PHYTEC Meßtechnik GmbH 2004 L-608e_4
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Y : In the gray scale format only the gray value, the value of the
brightness of a pixel is stored. The color information is not
considered. This format is recommended if color is meaningless
for the evaluation.
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Y8: In the Y8-format the gray value of each pixel is
stored in sequence as a value with 8-bit, so that one
Byte corresponds to one pixel.
Now the format of an image to be digitized, is exactly defined. The
Grabber must now be instructed where and how to store the data of
the image in the memory.
Therefore it is required to reserve a region in the main memory of
sufficient size.
The Windows driver reserves an image memory space, in which the
image is placed.
How much memory will be used? This will be calculated from the size
of the image (number of pixels) and the required number of Bytes per
pixel (color resolution):
Memory requirements per field = hsize
.
vsize
.
pixel size [Byte]
The value pixel size can be depicted from Table 12.
For the format YUV2 and BtYUV it must be considered, that 2 or
8 pixels are combined logically and that the resolution of the image is
selected correspondingly. The value calculated for the required region
of memory is valid for one field (even or odd). These values must be
added if a frame is required