diff options
| author | Laurent Pinchart <laurent.pinchart@ideasonboard.com> | 2022-09-04 03:57:08 +0300 |
|---|---|---|
| committer | Laurent Pinchart <laurent.pinchart@ideasonboard.com> | 2022-09-28 05:41:15 +0300 |
| commit | c43c8b1fa0d3dff50b017c33fc8d611a3f1da18e (patch) | |
| tree | 9a010700f5ce0e89dd6ab8dcdaa683bb9f10f628 /src | |
| parent | 7d0004a410db6a52b8c212294ce267c14f8300ac (diff) | |
ipa: rkisp1: awb: Prevent RGB means from being negative
Due to hardware rounding errors in the YCbCr means, the calculated RGB
means may be negative. This would lead to negative gains, messing up
calculation. Prevent this by clamping the means to positive values.
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
Reviewed-by: Jacopo Mondi <jacopo@jmondi.org>
Diffstat (limited to 'src')
| -rw-r--r-- | src/ipa/rkisp1/algorithms/awb.cpp | 10 |
1 files changed, 10 insertions, 0 deletions
diff --git a/src/ipa/rkisp1/algorithms/awb.cpp b/src/ipa/rkisp1/algorithms/awb.cpp index 139c8239..59664d09 100644 --- a/src/ipa/rkisp1/algorithms/awb.cpp +++ b/src/ipa/rkisp1/algorithms/awb.cpp @@ -242,6 +242,16 @@ void Awb::process(IPAContext &context, redMean = 1.1636 * yMean - 0.0623 * cbMean + 1.6008 * crMean; greenMean = 1.1636 * yMean - 0.4045 * cbMean - 0.7949 * crMean; blueMean = 1.1636 * yMean + 1.9912 * cbMean - 0.0250 * crMean; + + /* + * Due to hardware rounding errors in the YCbCr means, the + * calculated RGB means may be negative. This would lead to + * negative gains, messing up calculation. Prevent this by + * clamping the means to positive values. + */ + redMean = std::max(redMean, 0.0); + greenMean = std::max(greenMean, 0.0); + blueMean = std::max(blueMean, 0.0); } /* |