SPRUIE9D May 2017 – May 2024 DRA74P , DRA75P , DRA76P , DRA77P
CNF removes residual chroma noise (color variation seen in dark area of low light images. Usually in low frequency) by filtering UV data component of the image with noise filter. CNF is resided beside RSZ, and takes in UV and gives them back to RSZ.
CNF works with RSZ, and filters noises in chroma (UV or Cb/Cr) channel. CNF filters UV part of YUV420 image data. CNF only works on YUV420-UV, YUV420-YUV. It does not support YUV422 and YUV420-Y. One (CNFA) is attached to RSZ-A. CNFA supports up to 2816 pixels/line. The core of CNF is based on NSF3V UV processing. The functions of CNF are
Figure 9-108 show the CNF module connections to other submodules of the ISP.