From 4fdf1e4f5e9dce03f9506999f610eb6b1277e1b7 Mon Sep 17 00:00:00 2001 From: Jean-Michel Hautbois Date: Thu, 4 Nov 2021 14:20:42 +0100 Subject: ipa: ipu3: agc: Compute the gain for each frame Now that we have the real exposure applied at each frame, remove the early return based on a frame counter and compute the gain for each frame. Introduce a number of startup frames during which the filter speed is 1.0, meaning we apply instantly the exposure value calculated and not a slower filtered one. This is used to have a faster convergence, and those frames may be dropped in a future development to hide the convergance process from the viewer. Signed-off-by: Jean-Michel Hautbois Reviewed-by: Kieran Bingham Reviewed-by: Umang Jain Reviewed-by: Paul Elder --- src/ipa/ipu3/algorithms/agc.cpp | 26 +++++++++++--------------- src/ipa/ipu3/algorithms/agc.h | 1 - 2 files changed, 11 insertions(+), 16 deletions(-) (limited to 'src/ipa') diff --git a/src/ipa/ipu3/algorithms/agc.cpp b/src/ipa/ipu3/algorithms/agc.cpp index 83aa3676..74bce7bb 100644 --- a/src/ipa/ipu3/algorithms/agc.cpp +++ b/src/ipa/ipu3/algorithms/agc.cpp @@ -45,11 +45,6 @@ namespace ipa::ipu3::algorithms { LOG_DEFINE_CATEGORY(IPU3Agc) -/* Number of frames to wait before calculating stats on minimum exposure */ -static constexpr uint32_t kInitialFrameMinAECount = 4; -/* Number of frames to wait between new gain/shutter time estimations */ -static constexpr uint32_t kFrameSkipCount = 6; - /* Limits for analogue gain values */ static constexpr double kMinAnalogueGain = 1.0; static constexpr double kMaxAnalogueGain = 8.0; @@ -69,10 +64,13 @@ static constexpr double kEvGainTarget = 0.5; */ static constexpr uint32_t kMinCellsPerZoneRatio = 255 * 20 / 100; +/* Number of frames to wait before calculating stats on minimum exposure */ +static constexpr uint32_t kNumStartupFrames = 10; + Agc::Agc() - : frameCount_(0), lastFrame_(0), iqMean_(0.0), lineDuration_(0s), - minExposureLines_(0), maxExposureLines_(0), filteredExposure_(0s), - currentExposure_(0s), prevExposureValue_(0s) + : frameCount_(0), iqMean_(0.0), lineDuration_(0s), minExposureLines_(0), + maxExposureLines_(0), filteredExposure_(0s), currentExposure_(0s), + prevExposureValue_(0s) { } @@ -159,6 +157,11 @@ void Agc::measureBrightness(const ipu3_uapi_stats_3a *stats, void Agc::filterExposure() { double speed = 0.2; + + /* Adapt instantly if we are in startup phase */ + if (frameCount_ < kNumStartupFrames) + speed = 1.0; + if (filteredExposure_ == 0s) { /* DG stands for digital gain.*/ filteredExposure_ = currentExposure_; @@ -185,13 +188,6 @@ void Agc::filterExposure() */ void Agc::computeExposure(IPAFrameContext &frameContext) { - /* Algorithm initialization should wait for first valid frames */ - /* \todo - have a number of frames given by DelayedControls ? - * - implement a function for IIR */ - if ((frameCount_ < kInitialFrameMinAECount) || (frameCount_ - lastFrame_ < kFrameSkipCount)) - return; - - lastFrame_ = frameCount_; /* Are we correctly exposed ? */ if (std::abs(iqMean_ - kEvGainTarget * knumHistogramBins) <= 1) { diff --git a/src/ipa/ipu3/algorithms/agc.h b/src/ipa/ipu3/algorithms/agc.h index f0db25ee..99c60d46 100644 --- a/src/ipa/ipu3/algorithms/agc.h +++ b/src/ipa/ipu3/algorithms/agc.h @@ -37,7 +37,6 @@ private: void computeExposure(IPAFrameContext &frameContext); uint64_t frameCount_; - uint64_t lastFrame_; double iqMean_; -- cgit v1.2.1