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ipa: raspberrypi: Estimate the colour temerature if starting with fixed colour gains

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When the AWB is started from "cold" with fixed colour gains, we try to
estimate the colour temperature this corresponds to (if a calibrated
CT curve was supplied). When fixed colour gains are set after the AWB
has been running, we leave the CT estimate alone, as the one we have
is probably sensible.

This estimated colour is passed out in the metadata for other
algorithms - notably ALSC - to use.

Signed-off-by: David Plowman <david.plowman@raspberrypi.com>
Reviewed-by: Naushir Patuck <naush@raspberrypi.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
This commit is contained in:
David Plowman 2020-12-08 20:44:40 +00:00 • committed by Laurent Pinchart
parent 1a6a7d4a8e
commit 4cd283acd0
3 changed files with 20 additions and 1 deletions
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6
src/ipa/raspberrypi/controller/rpi/alsc.cpp
View file

@ -146,6 +146,7 @@ void Alsc::Read(boost::property_tree::ptree const &params)
config_.threshold = params.get<double>("threshold", 1e-3);
}
static double get_ct(Metadata *metadata, double default_ct);
static void get_cal_table(double ct,
std::vector<AlscCalibration> const &calibrations,
double cal_table[XY]);
@ -210,6 +211,9 @@ void Alsc::SwitchMode(CameraMode const &camera_mode,
// change.
bool reset_tables = first_time_ || compare_modes(camera_mode_, camera_mode);
// Believe the colour temperature from the AWB, if there is one.
ct_ = get_ct(metadata, ct_);
// Ensure the other thread isn't running while we do this.
waitForAysncThread();
@ -254,7 +258,7 @@ void Alsc::fetchAsyncResults()
memcpy(sync_results_, async_results_, sizeof(sync_results_));
}
static double get_ct(Metadata *metadata, double default_ct)
double get_ct(Metadata *metadata, double default_ct)
{
AwbStatus awb_status;
awb_status.temperature_K = default_ct; // in case nothing found

14
src/ipa/raspberrypi/controller/rpi/awb.cpp
View file

@ -19,6 +19,9 @@ using namespace RPiController;
const double Awb::RGB::INVALID = -1.0;
// todo - the locking in this algorithm needs some tidying up as has been done
// elsewhere (ALSC and AGC).
void AwbMode::Read(boost::property_tree::ptree const &params)
{
ct_lo = params.get<double>("lo");
@ -121,6 +124,7 @@ Awb::Awb(Controller *controller)
async_abort_ = async_start_ = async_started_ = async_finished_ = false;
mode_ = nullptr;
manual_r_ = manual_b_ = 0.0;
first_switch_mode_ = true;
async_thread_ = std::thread(std::bind(&Awb::asyncFunc, this));
}
@ -199,9 +203,19 @@ void Awb::SwitchMode([[maybe_unused]] CameraMode const &camera_mode,
prev_sync_results_.gain_r = manual_r_;
prev_sync_results_.gain_g = 1.0;
prev_sync_results_.gain_b = manual_b_;
// If we're starting up for the first time, try and
// "dead reckon" the corresponding colour temperature.
if (first_switch_mode_ && config_.bayes) {
Pwl ct_r_inverse = config_.ct_r.Inverse();
Pwl ct_b_inverse = config_.ct_b.Inverse();
double ct_r = ct_r_inverse.Eval(ct_r_inverse.Domain().Clip(1 / manual_r_));
double ct_b = ct_b_inverse.Eval(ct_b_inverse.Domain().Clip(1 / manual_b_));
prev_sync_results_.temperature_K = (ct_r + ct_b) / 2;
}
sync_results_ = prev_sync_results_;
}
metadata->Set("awb.status", prev_sync_results_);
first_switch_mode_ = false;
}
void Awb::fetchAsyncResults()

1
src/ipa/raspberrypi/controller/rpi/awb.hpp
View file

@ -159,6 +159,7 @@ private:
double manual_r_;
// manual b setting
double manual_b_;
bool first_switch_mode_; // is this the first call to SwitchMode?
};
static inline Awb::RGB operator+(Awb::RGB const &a, Awb::RGB const &b)