SPRUIE9D May 2017 – May 2024 DRA74P , DRA75P , DRA76P , DRA77P
In the ISIF, a DPCM compression block is between the culling module and the storage formatter module. This block can compress 12-bit image data to 8 bits for bandwidth reduction in transmission between the ISIF and SDRAM. An 8-to-12-bit DPCM decoder at the IPIPEIF decompresses data for IPIPE processing.
Two different predictors are used for the compression system. The first predictor is simple (simple predictor), and the second predictor is slightly more complex (advanced predictor). Because the advanced predictor gives a slightly better prediction for the pixel value, the image quality can be improved using it. Because the simple predictor is very basic, the processing power and memory requirements are reduced using it, when the image quality is already sufficiently high.
The function is controlled from the ISIF_MISC[12] DPCMEN and ISIF_MISC[13] DPCMPRE bits.