Omnivision CameraChip OV9650, Implementation Manual

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Timing Generator
Version 1.1, December 7, 2004 Proprietary to OmniVision Technologies 19
O
mni ision
3.5 Strobe Flash Control
To achieve the best image quality possible in low light conditions, the use of a strobe flash is
recommended. The OV9650 supports rolling shutter exposure mode.
To avoid the need for a mechanical shutter, the OV9650 should be set to rolling shutter mode. When
the rolling shutter mode is enabled and the image requires strobe flash illumination, the strobe
timing must be limited. Timing diagrams for strobe flash timing are shown in
Figure 3-4 and
Figure 3-5 .
Figure 3-3 SXGA Strobe Flash Timing Diagram
Figure 3-4 VGA Strobe Flash Timing Diagram
Figure 3-5 QVGA Strobe Flash Timing Diagram
VSYNC
Line Output
1 2 0 0 1 2 0
Line Reset
0 1 2
1023 1024
1023 1024
0 0 1 2
Note: If using live video mode for still capture
and if flash is required, use maximum
exposure (1 frame) and turn on flash only
between this gray period.
Exposure Time ~= 1 Tframe
12 x Tline
4 x Tline
9 x Tline
1023
1023
1024
VSYNC
Line Output
1 2
479
480 0 0 1 2 479 0
Line Reset
0 1 2 479 480 0 0 1 2 479 480
Note: If using live video mode for still capture
and if flash is required, use maximum
exposure (1 frame) and turn on flash only
between this gray period.
Exposure Time ~= 1 Tframe
8 x Tline
4 x Tline
5 x Tline
VSYNC
Line Output
1 2
239
240 0 0 1 2 239 0
Line Reset
0 1 2 239 240 0 0 1 2 239 240
Note: If using live video mode for still capture
and if flash is required, use maximum
exposure (1 frame) and turn on flash only
between this gray period.
Exposure Time ~= 1 Tframe
7 x Tline
2 x Tline