VS6724 Datasheet, PDF (15/118 Pages) STMicroelectronics – 2 Megapixel single-chip camera module

VS6724
Figure 5. Crop controls
Sensor array horizontal size
Functional description
uwManualCropHorizontalStart
uwManualCropVerticalStart
Cropped ROI
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uwManualCropHorizontalSize
FFOV
2.4.6
2.4.7
2.4.8
Note:
Zoom
The zoom function found in the pipe context control sections can be used to achieve a
continuous zoom by simply selecting the commands zoom_in, zoom_out and zoom_stop. It
is also possible to perform a single step of zoom by selecting Zoom_step_in and
Zoom_step_out.
It is possible to zoom between the sensor size selected and the output size (the output size
must be smaller that the sensor mode size, UXGA or SVGA).
Pan
It is possible to pan left, right, up and down when the output size selected is smaller than the
sensor size selected (if the output size selected equals the sensor mode size then no pan
can take place).
The pan step size in both the horizontal and vertical directions are selectable.
Derating
The VS6724 contains an internal derating module. This is designed to reduce the peak
output data rate of the device by spreading the data over the whole frame period and
allowing a subsequent reduction in output clock frequency.
The maximum achievable derating factor is x400 for an equivalent scale factor of x20
downscale. As a general rule the allowable derating factor is equal to the square of the
scaling factor.
The interline period is not guaranteed to be consistent for all derating ratios. This means the
host capture system must be able to cope with use of the sync signals or embedded codes
rather than relying on fixed line counts.
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