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Theory of Operation
X64-AN Quad User's Manual
Cropper
The Cropper extracts a window from the incoming image. This window is represented by a rectangle
where the upper-left corner is given by horizontal and vertical offset from the start of valid video and
the rectangle size by width and height parameters. See below for diagram. Note that image widths
must be a multiple of 16 bytes. For interlace scan video, image heights must be a multiple of two lines.
Horizontal offset
Vertical offset
Width
Height
Window Generator
Complete frame
Window
Figure 29: Cropper window example
Partial Scan Mode
Partial Scan mode reduces the number of lines output by a camera in order to increase the frame rate.
X64-AN Quad
sees the output of a partial scan camera as an image with reduced height. One simply
needs to adjust the frame rate (vertical sync frequency) and image height in order to acquire from a
partial scan mode camera.
Sapera Parameters for Cropper:
CORACQ_PRM_CROP_LEFT: Horizontal offset
CORACQ_PRM_CROP_HEIGHT: Vertical height of area of interest
CORACQ_PRM_CROP_TOP: Vertical offset
CORACQ_PRM_CROP_WIDTH: Horizontal width of area of interest
