Instruction manual

Description of the data path
8.3 White balance
color cameras have both manual and automatic white balance. White balance is applied so
at non-colored image parts are displayed non-colored.
White balance does not use the so called PxGA® (P end
litude modulation from the sensor is in the form of
The
th
ixel Gain Amplifier) of the analog front
(AFE) but a digital representation in the FPGA in order to modify the gain of the two channels
with lower output by +9.5dB (in 106 steps) relative to the channel with highest output.
The following screenshot is taken from the datasheet of the AFE and illustrates the details:
e analog color signal, coming in pulse ampTh
the BAYER™ color pattern sequence. It is initially processed in the CDS (correlated double
sampler) then bypasses the PxGA before further amplification and digitization.
Figure 31: Block diagram of AFE (Source: Analog Devices)
From the user’s point, the white balance settings are made in register 80Ch of IIDC v. 1.3. This
register is described in more detail on the next page.
MARLIN Technical Manua
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