Video and Color Space

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Video and Color Space
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Camera Spec
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Issues with Video Signal

• Square Pixel Issue
• NTSC 640 pixels per line at 12.2727 MHz
• PAL 768 pixels per line at 14.75 MHz
• Aspect ratio correction
• White Balance Issue
• RGB three channels must output the same
  grayscale values when imaging a white scene
• Gain Adjustment Issue
• Auto gain based on video signal in Back Porch
  area

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Video Signal Format
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Color Space

• Video Signal
• NTSC composite or Y/C
• Color Space
• RGB, YUV, HIS, YCbCr, CMYK, YIQ, .
• RGB, YUV, and HIS are all 3-dimensional
• Y (luma) and UV(color information)
• Conversion can be done among all three.

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Color Space Representation
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Color Segmentation
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Color Segmentation
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Color Segmentation
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Color Segmentation

• Use HSI
• Threshold in hue
• Discontinuity
• High or low I
• Try 2-D instead of 3_D ?