Phytec pciGrabber4x4, Руководство по оборудованию

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pciGrabber-4x4
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PHYTEC Messtechnik GmbH 2008 L-720e_0
To get a clear transfer of the data volume the maximum data rate of
the PCI bus must not be exceeded. In addition, a safety distance of
~15% to the 132 MB/s must be adhered to. So the maximum data
without overloading the PCI bus is 112 MB/s
Numbers of
decoders
RGB32
768 x 576
RGB32
640 x 480
RGB32
620 x 450
RGB16
768 x 576
Y8 Gray
768 x 576
1 44,2 MB/s 30,7 MB/s 27,9 MB/s 22,1 MB/s 11,1 MB/s
2 88,5 MB/s 61,4 MB/s 55,8 MB/s 44,2 MB/s 22,1 MB/s
3 132,7 MB/s 92,2 MB/s 83,7 MB/s 66,4 MB/s 33,2 MB/s
4 176,9 MB/s 122,9 MB/s 111,6 MB/s 88,5 MB/s 44,2 MB/s
Table 7 Example data volumes PAL 25fps
Numbers of
decoders
RGB32
720 x 480
RGB32
640 x 480
RGB32
580 x 400
RGB16
720 x 480
Y8 Gray
720 x 480
1 41,5 MB/s 36,9 MB/s 27,8 MB/s 20,7 MB/s 10,4 MB/s
2 82,9 MB/s 73,7 MB/s 55,7 MB/s 41,5 MB/s 20,7 MB/s
3 124,4 MB/s 110,6 MB/s 83,5 MB/s 62,2 MB/s 31,1 MB/s
4 165,9 MB/s 147,5 MB/s 111,4 MB/s 82,9 MB/s 41,5 MB/s
Table 8 Example data volumes NTSC 30fps
If the 112 MB/s are not exceeded an unproblematic data transfer is
possible. To see as in Table 7 and Table 8 it exists many possibilities
to reduce the volume of the data.
1. Reduce the resolutio
2. Reduce the colour depth
3. Reduce the display regeneration rate
With the help of equation 1 can compute the data volume and decide
which settings for the suitable application suits.