Colour conversion is necessary to translate the RGB data received from the sensor to a standard RGB space. It is used to convert the image data from colours that the camera “sees” to colours that a person would see in the same environment. 


Applying a matrix transform to the RGB data from the sensor performs this colour correction. This same matrix transform is used to apply saturation. The transform is represented by the following equation:


 


Where CCM is the colour correction matrix.


The correction matrix changes for different cameras and lighting environments. Each correction matrix is optimised for a different light source. The colour temperature of the light source identifies the different colour correction matrices. For example, 3200K = incandescent and 5000K = daylight.


The following example pictures show corrected and uncorrected images under incandescent lighting.



Uncorrected Image



Corrected Image


When To Use


This feature should always be used in colour cameras.  The user should select the proper colour temperature in order to optimise the colour setting

How To Use


The colour correction can be set based on the illumination being used and it can also be turned off completely if needed.  There are three ways of controlling the colour correction on Pixelink Cameras:

  • Using the Colour Temperature control in Pixelink Capture OEM.
  • By writing software using the Pixelink SDK
Note:  FEATURE_WHITE_BALANCE represents colour correction in the SDK
  •  By writing software that uses the IIDC protocol to control the white balance feature
Note: The absolute value registers must be used to set the colour temperature