SPRUIE9D May 2017 – May 2024 DRA74P , DRA75P , DRA76P , DRA77P
For the memory access locations of the gamma correction module, see Section 9.3.3.11, ISS ISP Memory Mapping.
The gamma correction module performs gamma correction independently for each color in the RGB color space by using a piece-wise linear interpolation. ROM tables and RAM tables are selectable through the IPIPE_GMM_CFG[4] TBL bit. Each ROM table and RAM table has 512 entries, and each entry accommodates a 10-bit offset and 10-bit slope. The range of slope value is from –512 to +511. The ROM table has 1024 entries and an output 8-bit value.
Figure 9-70 is a block diagram of the gamma correction module. It is composed of two tables and one selector. When the BYPASS bit is asserted, the input data is divided by 16 (the IPIPE_GMM_CFG[0] BYPR, IPIPE_GMM_CFG[1] BYPG, and IPIPE_GMM_CFG[2] BYPB bits).
Figure 9-71 shows an example of the gamma curve. Figure 9-72 shows offset and slope packing.