Texas Instruments MULTICAM MC-1134P, Руководство пользователя

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Mode Selection
B-19 Operation
4.4.3
Description of Selectable Modes
NORMAL LIGHT: The normal light sensitivity mode provides true interlace
with 486 lines per frame and 1,134 pixels per line. After a 1/60 second
exposure of the 486 active lines in the image area, one field of 243 lines
becomes video; the other 243 lines are discarded. A subsequent 1/60 second
exposure produces the additional 243 lines to complete the interlaced frame.
LOW LIGHT: The low-light-sensitivity mode uses pseudo-interlace by
summing two adjacent lines after a 1/60 second exposure. The alternate
summing of lines provides two different fields for each frame. The summing
of two lines provides a 2:1 gain in light sensitivity. Pseudo-interlace mode
produces slightly less vertical resolution than true interlace mode.
DUAL FIELD: The simultaneous field capture mode exposes the
486- x 1,134-pixel image area for 1/30 second. Both fields are exposed at the
same time, stored on chip and, after readout, form a frame having true
interlace without the time-dependent image offset that occurs with standard
field-mode operation. Due to the longer exposure time, the light sensitivity in
dual-field mode is equivalent to that in the low-light-sensitivity mode and the
higher vertical resolution of true interlace mode is preserved.
PROGRESSIVE SCAN: This simultaneous field capture mode exposes the
486- x 1,134-pixel image area for 1/30 second. Both fields are exposed at the
same time, stored on chip, and then read out alternating between the two
fields. This forms a field of 1134 x 488 pixels having true interlace. This
information is read out in 1/30 second. The light sensitivity is equivalent to the
low-light-sensitivity mode due to the longer exposure time, and the higher
vertical resolution of true interlace is preserved. There is no frame readout in
this mode.