SPRUJ28E November 2021 – September 2024 AM68 , AM68A , TDA4AL-Q1 , TDA4VE-Q1 , TDA4VL-Q1
The output from the saturation check module and the subsampler module are separately accumulated for each pixel in every 2 × 2 pixel block for each window. Therefore, there are eight accumulators per window (one accumulator for each pixel in a 2 × 2 pixel block, times two sets of accumulators: clipped/saturated data and presaturated data). Each of the 4 pixels in the 2 × 2 pixel grid is associated with a color R, Gr, B, Gb); however, the output of these accumulators is referenced by position in the grid, not color.
The accumulators are 16 bits wide, and the accumulated data is 10 bits wide. Therefore, when a window contains more than 64 pixels of the same color, an overflow risk exists. This risk can be reduced by enabling the A-Law conversion in the preprocessing stage. See Section 6.7.3.2.4.6.4 for details.
The AE/AWB module has a shift value for the accumulation of pixel values that is set in the VISS_RAWFE_H3A_AEWCFG[3:0] SUMSHFT bit field.