Hitachi Camera Signal Processing LSI HD49815TF Color

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Hitachi Camera Signal Processing LSI (HD49815TF)
Color Luminance Processing

• B88901136 ???

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System Block Diagram

• Hitachi Camera System Configuration

We emphasize on (1)(2)!
(1)
10-bit A/D input
(2)
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System Block Diagram(1)

• Color Signal Processing Block Diagram

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System Block Diagram(2)

• Luminance Signal Processing Block Diagram

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Color Signal Processing Block(1)

• C-limit (complementary color clipping level )
  functionHigh clipping processing is performed on
  the complementary color signals
  independently.Gb(GCy),Wr(YeMg),Wb(MgCy),Gr(GY
  e)
• RGB-Matrix Block3 primary colors are acquired in
  the RGB matrix by multiplying arbitrary
  coefficients by the 4 complementary colors.
• RGB-setup BlockThe black level of the color
  signals is variable according to the coefficients
  of the RGB matrix.

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Color Signal Processing Block(2)

• RGB-gain blockAcquired in the AWB block.It is to
  improve the white reproduction performance.It
  also change the gamma correction amount.
• Gamma correction blockC-gamma darkreduce the
  gain of the small signal.Improve S/N.C-gamma
  coefficientcontrol the expansion of the gamma
  curve.C-gamma kneedecide the slope of the large
  signals.C-gamma limitperform high-clipping
  processing for the input signal of the C gamma
  circuit.
• Axis-conversionR-G,B-G R-Y,B-Y
• Base-clipping clockPerformed on color difference
  signal to characterized the sections near axes on
  a vector scope.

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Luminance Signal Processing Block(1)

• H-enhancer functionCore level,enhancer
  gain,noise coefficient can be set independently
  to acquire optimal characteristic.
• V-enhancer functionAllows the enhancer gain
  coefficient to be set and can control the gain
  for only those signal components that exceed the
  set core level.
• Luminance correctionThe ratio of the red and
  blue levels changes according to the color
  temperature of the imaged object.
• Y setupThis circuit subtracts 48 at the black
  level.However,when 48 at the black level differs
  due to the noise mixed in the analog signal,the
  Y-setup circuit subtracts that value.

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Luminance Signal Processing Block(2)

• Gamma correctionImplements the gamma-correction
  processing for the separated Y-signal.According
  to the input-signal level,to acquire optimal
  gamma characteristics1.gamma input
  limit2.gamma knee coefficient3.gamma
  coefficient4.gamma black clipping
• Highlight enhancerFor input-Y signal levels in
  excess of 100IRE, the highlight enhanced
  implements highlight enhancer processing
• FadeAmplifies the luminance signal by a factor
  of 0 to 1.