Modified Laroche Bayer De-Mosaicing Algorithm

Brief Description

File: \examples\Processing\Color\Bayer\Laroche_modified_maVCL.va

Default Platform: mE5-MA-VCL

Short Description

Resource optimized Bayer De-Mosaicing Algorithm According to Laroche

In this section we describe a slightly modified version of the Bayer demosaicing algorithm of 'Bayer De-Mosaicing Algorithm According to Laroche'. The only difference in the interpolation algorithm (see Equation 8 to Equation 12) is, that the green color values () for the interpolation of the red and blue color values (Equation 10 to Equation 12) are bilinearly interpolated. All other color interpolation steps are equivalent to the "original Laroche filter". In 'Bayer De-mosaicing ' the qualitative difference in the Bayer demosaicing results are presented. You can find the corresponding VisualApplets example for the modified version under \examples\Processing\Color\Bayer\Laroche_modified_maVCL.va. It is implemented for a microEnable 5 frame grabber for 8 bit input bit depth and a parallelism of 2 but can easily adapted to a version for a microEnable IV frame grabber, other input bit depths or parallelisms. In the following shortly the modified parts in the VisualApplets design are presented. In Figure 248, 'Content of ColourInterpolation for the modified Laroche filter.' you can see the content of the HierarchicalBox ColourInterpolation (see Figure 242, 'Interpolation step 1 of the Bayer-demosaicing process').

Content of ColourInterpolation for the modified Laroche filter.

Figure 248. Content of ColourInterpolation for the modified Laroche filter.


The red and blue color values are interpolated in the box RedandBlue out of a ) kernel of a Bayer pattern and the calculated green value at the current pixel position. The calculation of the green value is done in the HierarchicalBox GreenOut. Equivalent to the example in 'Bayer De-Mosaicing Algorithm According to Laroche' the color at the current pixel position is found in whereAmI_Colour. All three color components are finally merged together.