From 59687683a16c64c6821db89c7a1be35b161bf917 Mon Sep 17 00:00:00 2001 From: Jean-Michel Hautbois Date: Thu, 30 Sep 2021 11:05:16 +0200 Subject: ipa: ipu3: awb: Set a threshold for the green saturation We can have a saturation ratio per cell, giving the percentage of pixels over a threshold within a cell where 100% is set to 0xff. The parameter structure 'ipu3_uapi_awb_config_s' contains four fields to set the threshold, one per channel. The blue field is also used to configure the ImgU and make it calculate the saturation ratio or not. Set a green value saturated when it is more than 230 (90% of the maximum value 255, coded as 8191). As this is the only channel used for AGC, there is no need to apply it to the other ones. Signed-off-by: Jean-Michel Hautbois Reviewed-by: Laurent Pinchart Reviewed-by: Kieran Bingham --- src/ipa/ipu3/algorithms/awb.cpp | 27 +++++++++++++++++++++------ 1 file changed, 21 insertions(+), 6 deletions(-) (limited to 'src/ipa/ipu3/algorithms/awb.cpp') diff --git a/src/ipa/ipu3/algorithms/awb.cpp b/src/ipa/ipu3/algorithms/awb.cpp index 809de66a..4364928c 100644 --- a/src/ipa/ipu3/algorithms/awb.cpp +++ b/src/ipa/ipu3/algorithms/awb.cpp @@ -328,14 +328,29 @@ void Awb::process(IPAContext &context, const ipu3_uapi_stats_3a *stats) context.frameContext.awb.gains.red = asyncResults_.redGain; } +constexpr uint16_t Awb::threshold(float value) +{ + /* AWB thresholds are in the range [0, 8191] */ + return value * 8191; +} + void Awb::prepare(IPAContext &context, ipu3_uapi_params *params) { - params->acc_param.awb.config.rgbs_thr_gr = 8191; - params->acc_param.awb.config.rgbs_thr_r = 8191; - params->acc_param.awb.config.rgbs_thr_gb = 8191; - params->acc_param.awb.config.rgbs_thr_b = IPU3_UAPI_AWB_RGBS_THR_B_INCL_SAT - | IPU3_UAPI_AWB_RGBS_THR_B_EN - | 8191; + /* + * Green saturation thresholds are reduced because we are using the + * green channel only in the exposure computation. + */ + params->acc_param.awb.config.rgbs_thr_r = threshold(1.0); + params->acc_param.awb.config.rgbs_thr_gr = threshold(0.9); + params->acc_param.awb.config.rgbs_thr_gb = threshold(0.9); + params->acc_param.awb.config.rgbs_thr_b = threshold(1.0); + + /* + * Enable saturation inclusion on thr_b for ImgU to update the + * ipu3_uapi_awb_set_item->sat_ratio field. + */ + params->acc_param.awb.config.rgbs_thr_b |= IPU3_UAPI_AWB_RGBS_THR_B_INCL_SAT | + IPU3_UAPI_AWB_RGBS_THR_B_EN; const ipu3_uapi_grid_config &grid = context.configuration.grid.bdsGrid; -- cgit v1.2.1