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-rw-r--r--src/ipa/simple/algorithms/agc.cpp139
-rw-r--r--src/ipa/simple/algorithms/agc.h33
-rw-r--r--src/ipa/simple/algorithms/algorithm.h22
-rw-r--r--src/ipa/simple/algorithms/awb.cpp69
-rw-r--r--src/ipa/simple/algorithms/awb.h32
-rw-r--r--src/ipa/simple/algorithms/blc.cpp95
-rw-r--r--src/ipa/simple/algorithms/blc.h36
-rw-r--r--src/ipa/simple/algorithms/lut.cpp86
-rw-r--r--src/ipa/simple/algorithms/lut.h34
-rw-r--r--src/ipa/simple/algorithms/meson.build8
10 files changed, 554 insertions, 0 deletions
diff --git a/src/ipa/simple/algorithms/agc.cpp b/src/ipa/simple/algorithms/agc.cpp
new file mode 100644
index 00000000..df92edd7
--- /dev/null
+++ b/src/ipa/simple/algorithms/agc.cpp
@@ -0,0 +1,139 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+/*
+ * Copyright (C) 2024, Red Hat Inc.
+ *
+ * Exposure and gain
+ */
+
+#include "agc.h"
+
+#include <stdint.h>
+
+#include <libcamera/base/log.h>
+
+namespace libcamera {
+
+LOG_DEFINE_CATEGORY(IPASoftExposure)
+
+namespace ipa::soft::algorithms {
+
+/*
+ * The number of bins to use for the optimal exposure calculations.
+ */
+static constexpr unsigned int kExposureBinsCount = 5;
+
+/*
+ * The exposure is optimal when the mean sample value of the histogram is
+ * in the middle of the range.
+ */
+static constexpr float kExposureOptimal = kExposureBinsCount / 2.0;
+
+/*
+ * This implements the hysteresis for the exposure adjustment.
+ * It is small enough to have the exposure close to the optimal, and is big
+ * enough to prevent the exposure from wobbling around the optimal value.
+ */
+static constexpr float kExposureSatisfactory = 0.2;
+
+Agc::Agc()
+{
+}
+
+void Agc::updateExposure(IPAContext &context, double exposureMSV)
+{
+ /*
+ * kExpDenominator of 10 gives ~10% increment/decrement;
+ * kExpDenominator of 5 - about ~20%
+ */
+ static constexpr uint8_t kExpDenominator = 10;
+ static constexpr uint8_t kExpNumeratorUp = kExpDenominator + 1;
+ static constexpr uint8_t kExpNumeratorDown = kExpDenominator - 1;
+
+ double next;
+ int32_t &exposure = context.activeState.agc.exposure;
+ double &again = context.activeState.agc.again;
+
+ if (exposureMSV < kExposureOptimal - kExposureSatisfactory) {
+ next = exposure * kExpNumeratorUp / kExpDenominator;
+ if (next - exposure < 1)
+ exposure += 1;
+ else
+ exposure = next;
+ if (exposure >= context.configuration.agc.exposureMax) {
+ next = again * kExpNumeratorUp / kExpDenominator;
+ if (next - again < context.configuration.agc.againMinStep)
+ again += context.configuration.agc.againMinStep;
+ else
+ again = next;
+ }
+ }
+
+ if (exposureMSV > kExposureOptimal + kExposureSatisfactory) {
+ if (exposure == context.configuration.agc.exposureMax &&
+ again > context.configuration.agc.againMin) {
+ next = again * kExpNumeratorDown / kExpDenominator;
+ if (again - next < context.configuration.agc.againMinStep)
+ again -= context.configuration.agc.againMinStep;
+ else
+ again = next;
+ } else {
+ next = exposure * kExpNumeratorDown / kExpDenominator;
+ if (exposure - next < 1)
+ exposure -= 1;
+ else
+ exposure = next;
+ }
+ }
+
+ exposure = std::clamp(exposure, context.configuration.agc.exposureMin,
+ context.configuration.agc.exposureMax);
+ again = std::clamp(again, context.configuration.agc.againMin,
+ context.configuration.agc.againMax);
+
+ LOG(IPASoftExposure, Debug)
+ << "exposureMSV " << exposureMSV
+ << " exp " << exposure << " again " << again;
+}
+
+void Agc::process(IPAContext &context,
+ [[maybe_unused]] const uint32_t frame,
+ [[maybe_unused]] IPAFrameContext &frameContext,
+ const SwIspStats *stats,
+ [[maybe_unused]] ControlList &metadata)
+{
+ /*
+ * Calculate Mean Sample Value (MSV) according to formula from:
+ * https://www.araa.asn.au/acra/acra2007/papers/paper84final.pdf
+ */
+ const auto &histogram = stats->yHistogram;
+ const unsigned int blackLevelHistIdx =
+ context.activeState.blc.level / (256 / SwIspStats::kYHistogramSize);
+ const unsigned int histogramSize =
+ SwIspStats::kYHistogramSize - blackLevelHistIdx;
+ const unsigned int yHistValsPerBin = histogramSize / kExposureBinsCount;
+ const unsigned int yHistValsPerBinMod =
+ histogramSize / (histogramSize % kExposureBinsCount + 1);
+ int exposureBins[kExposureBinsCount] = {};
+ unsigned int denom = 0;
+ unsigned int num = 0;
+
+ for (unsigned int i = 0; i < histogramSize; i++) {
+ unsigned int idx = (i - (i / yHistValsPerBinMod)) / yHistValsPerBin;
+ exposureBins[idx] += histogram[blackLevelHistIdx + i];
+ }
+
+ for (unsigned int i = 0; i < kExposureBinsCount; i++) {
+ LOG(IPASoftExposure, Debug) << i << ": " << exposureBins[i];
+ denom += exposureBins[i];
+ num += exposureBins[i] * (i + 1);
+ }
+
+ float exposureMSV = (denom == 0 ? 0 : static_cast<float>(num) / denom);
+ updateExposure(context, exposureMSV);
+}
+
+REGISTER_IPA_ALGORITHM(Agc, "Agc")
+
+} /* namespace ipa::soft::algorithms */
+
+} /* namespace libcamera */
diff --git a/src/ipa/simple/algorithms/agc.h b/src/ipa/simple/algorithms/agc.h
new file mode 100644
index 00000000..ad5fca9f
--- /dev/null
+++ b/src/ipa/simple/algorithms/agc.h
@@ -0,0 +1,33 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+/*
+ * Copyright (C) 2024, Red Hat Inc.
+ *
+ * Exposure and gain
+ */
+
+#pragma once
+
+#include "algorithm.h"
+
+namespace libcamera {
+
+namespace ipa::soft::algorithms {
+
+class Agc : public Algorithm
+{
+public:
+ Agc();
+ ~Agc() = default;
+
+ void process(IPAContext &context, const uint32_t frame,
+ IPAFrameContext &frameContext,
+ const SwIspStats *stats,
+ ControlList &metadata) override;
+
+private:
+ void updateExposure(IPAContext &context, double exposureMSV);
+};
+
+} /* namespace ipa::soft::algorithms */
+
+} /* namespace libcamera */
diff --git a/src/ipa/simple/algorithms/algorithm.h b/src/ipa/simple/algorithms/algorithm.h
new file mode 100644
index 00000000..41f63170
--- /dev/null
+++ b/src/ipa/simple/algorithms/algorithm.h
@@ -0,0 +1,22 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+/*
+ * Copyright (C) 2024 Red Hat, Inc.
+ *
+ * Software ISP control algorithm interface
+ */
+
+#pragma once
+
+#include <libipa/algorithm.h>
+
+#include "module.h"
+
+namespace libcamera {
+
+namespace ipa::soft {
+
+using Algorithm = libcamera::ipa::Algorithm<Module>;
+
+} /* namespace ipa::soft */
+
+} /* namespace libcamera */
diff --git a/src/ipa/simple/algorithms/awb.cpp b/src/ipa/simple/algorithms/awb.cpp
new file mode 100644
index 00000000..195de41d
--- /dev/null
+++ b/src/ipa/simple/algorithms/awb.cpp
@@ -0,0 +1,69 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+/*
+ * Copyright (C) 2024, Red Hat Inc.
+ *
+ * Auto white balance
+ */
+
+#include "awb.h"
+
+#include <numeric>
+#include <stdint.h>
+
+#include <libcamera/base/log.h>
+
+#include "simple/ipa_context.h"
+
+namespace libcamera {
+
+LOG_DEFINE_CATEGORY(IPASoftAwb)
+
+namespace ipa::soft::algorithms {
+
+int Awb::configure(IPAContext &context,
+ [[maybe_unused]] const IPAConfigInfo &configInfo)
+{
+ auto &gains = context.activeState.gains;
+ gains.red = gains.green = gains.blue = 1.0;
+
+ return 0;
+}
+
+void Awb::process(IPAContext &context,
+ [[maybe_unused]] const uint32_t frame,
+ [[maybe_unused]] IPAFrameContext &frameContext,
+ const SwIspStats *stats,
+ [[maybe_unused]] ControlList &metadata)
+{
+ const SwIspStats::Histogram &histogram = stats->yHistogram;
+ const uint8_t blackLevel = context.activeState.blc.level;
+
+ /*
+ * Black level must be subtracted to get the correct AWB ratios, they
+ * would be off if they were computed from the whole brightness range
+ * rather than from the sensor range.
+ */
+ const uint64_t nPixels = std::accumulate(
+ histogram.begin(), histogram.end(), 0);
+ const uint64_t offset = blackLevel * nPixels;
+ const uint64_t sumR = stats->sumR_ - offset / 4;
+ const uint64_t sumG = stats->sumG_ - offset / 2;
+ const uint64_t sumB = stats->sumB_ - offset / 4;
+
+ /*
+ * Calculate red and blue gains for AWB.
+ * Clamp max gain at 4.0, this also avoids 0 division.
+ */
+ auto &gains = context.activeState.gains;
+ gains.red = sumR <= sumG / 4 ? 4.0 : static_cast<double>(sumG) / sumR;
+ gains.blue = sumB <= sumG / 4 ? 4.0 : static_cast<double>(sumG) / sumB;
+ /* Green gain is fixed to 1.0 */
+
+ LOG(IPASoftAwb, Debug) << "gain R/B " << gains.red << "/" << gains.blue;
+}
+
+REGISTER_IPA_ALGORITHM(Awb, "Awb")
+
+} /* namespace ipa::soft::algorithms */
+
+} /* namespace libcamera */
diff --git a/src/ipa/simple/algorithms/awb.h b/src/ipa/simple/algorithms/awb.h
new file mode 100644
index 00000000..db1496cd
--- /dev/null
+++ b/src/ipa/simple/algorithms/awb.h
@@ -0,0 +1,32 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+/*
+ * Copyright (C) 2024, Red Hat Inc.
+ *
+ * Auto white balance
+ */
+
+#pragma once
+
+#include "algorithm.h"
+
+namespace libcamera {
+
+namespace ipa::soft::algorithms {
+
+class Awb : public Algorithm
+{
+public:
+ Awb() = default;
+ ~Awb() = default;
+
+ int configure(IPAContext &context, const IPAConfigInfo &configInfo) override;
+ void process(IPAContext &context,
+ const uint32_t frame,
+ IPAFrameContext &frameContext,
+ const SwIspStats *stats,
+ ControlList &metadata) override;
+};
+
+} /* namespace ipa::soft::algorithms */
+
+} /* namespace libcamera */
diff --git a/src/ipa/simple/algorithms/blc.cpp b/src/ipa/simple/algorithms/blc.cpp
new file mode 100644
index 00000000..b4e32fe1
--- /dev/null
+++ b/src/ipa/simple/algorithms/blc.cpp
@@ -0,0 +1,95 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+/*
+ * Copyright (C) 2024, Red Hat Inc.
+ *
+ * Black level handling
+ */
+
+#include "blc.h"
+
+#include <numeric>
+
+#include <libcamera/base/log.h>
+
+namespace libcamera {
+
+namespace ipa::soft::algorithms {
+
+LOG_DEFINE_CATEGORY(IPASoftBL)
+
+BlackLevel::BlackLevel()
+{
+}
+
+int BlackLevel::init(IPAContext &context, const YamlObject &tuningData)
+{
+ auto blackLevel = tuningData["blackLevel"].get<int16_t>();
+ if (blackLevel.has_value()) {
+ /*
+ * Convert 16 bit values from the tuning file to 8 bit black
+ * level for the SoftISP.
+ */
+ context.configuration.black.level = blackLevel.value() >> 8;
+ }
+ return 0;
+}
+
+int BlackLevel::configure(IPAContext &context,
+ [[maybe_unused]] const IPAConfigInfo &configInfo)
+{
+ context.activeState.blc.level =
+ context.configuration.black.level.value_or(255);
+ return 0;
+}
+
+void BlackLevel::process(IPAContext &context,
+ [[maybe_unused]] const uint32_t frame,
+ IPAFrameContext &frameContext,
+ const SwIspStats *stats,
+ [[maybe_unused]] ControlList &metadata)
+{
+ if (context.configuration.black.level.has_value())
+ return;
+
+ if (frameContext.sensor.exposure == exposure_ &&
+ frameContext.sensor.gain == gain_) {
+ return;
+ }
+
+ const SwIspStats::Histogram &histogram = stats->yHistogram;
+
+ /*
+ * The constant is selected to be "good enough", not overly
+ * conservative or aggressive. There is no magic about the given value.
+ */
+ constexpr float ignoredPercentage = 0.02;
+ const unsigned int total =
+ std::accumulate(begin(histogram), end(histogram), 0);
+ const unsigned int pixelThreshold = ignoredPercentage * total;
+ const unsigned int histogramRatio = 256 / SwIspStats::kYHistogramSize;
+ const unsigned int currentBlackIdx =
+ context.activeState.blc.level / histogramRatio;
+
+ for (unsigned int i = 0, seen = 0;
+ i < currentBlackIdx && i < SwIspStats::kYHistogramSize;
+ i++) {
+ seen += histogram[i];
+ if (seen >= pixelThreshold) {
+ context.activeState.blc.level = i * histogramRatio;
+ exposure_ = frameContext.sensor.exposure;
+ gain_ = frameContext.sensor.gain;
+ LOG(IPASoftBL, Debug)
+ << "Auto-set black level: "
+ << i << "/" << SwIspStats::kYHistogramSize
+ << " (" << 100 * (seen - histogram[i]) / total << "% below, "
+ << 100 * seen / total << "% at or below)";
+ break;
+ }
+ };
+}
+
+REGISTER_IPA_ALGORITHM(BlackLevel, "BlackLevel")
+
+} /* namespace ipa::soft::algorithms */
+
+} /* namespace libcamera */
diff --git a/src/ipa/simple/algorithms/blc.h b/src/ipa/simple/algorithms/blc.h
new file mode 100644
index 00000000..2cf2a877
--- /dev/null
+++ b/src/ipa/simple/algorithms/blc.h
@@ -0,0 +1,36 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+/*
+ * Copyright (C) 2024, Red Hat Inc.
+ *
+ * Black level handling
+ */
+
+#pragma once
+
+#include "algorithm.h"
+
+namespace libcamera {
+
+namespace ipa::soft::algorithms {
+
+class BlackLevel : public Algorithm
+{
+public:
+ BlackLevel();
+ ~BlackLevel() = default;
+
+ int init(IPAContext &context, const YamlObject &tuningData) override;
+ int configure(IPAContext &context, const IPAConfigInfo &configInfo) override;
+ void process(IPAContext &context, const uint32_t frame,
+ IPAFrameContext &frameContext,
+ const SwIspStats *stats,
+ ControlList &metadata) override;
+
+private:
+ uint32_t exposure_;
+ double gain_;
+};
+
+} /* namespace ipa::soft::algorithms */
+
+} /* namespace libcamera */
diff --git a/src/ipa/simple/algorithms/lut.cpp b/src/ipa/simple/algorithms/lut.cpp
new file mode 100644
index 00000000..9744e773
--- /dev/null
+++ b/src/ipa/simple/algorithms/lut.cpp
@@ -0,0 +1,86 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+/*
+ * Copyright (C) 2024, Red Hat Inc.
+ *
+ * Color lookup tables construction
+ */
+
+#include "lut.h"
+
+#include <algorithm>
+#include <cmath>
+#include <stdint.h>
+
+#include <libcamera/base/log.h>
+
+#include "simple/ipa_context.h"
+
+namespace libcamera {
+
+namespace ipa::soft::algorithms {
+
+int Lut::configure(IPAContext &context,
+ [[maybe_unused]] const IPAConfigInfo &configInfo)
+{
+ /* Gamma value is fixed */
+ context.configuration.gamma = 0.5;
+ updateGammaTable(context);
+
+ return 0;
+}
+
+void Lut::updateGammaTable(IPAContext &context)
+{
+ auto &gammaTable = context.activeState.gamma.gammaTable;
+ auto blackLevel = context.activeState.blc.level;
+ const unsigned int blackIndex = blackLevel * gammaTable.size() / 256;
+
+ std::fill(gammaTable.begin(), gammaTable.begin() + blackIndex, 0);
+ const float divisor = gammaTable.size() - blackIndex - 1.0;
+ for (unsigned int i = blackIndex; i < gammaTable.size(); i++)
+ gammaTable[i] = UINT8_MAX * std::pow((i - blackIndex) / divisor,
+ context.configuration.gamma);
+
+ context.activeState.gamma.blackLevel = blackLevel;
+}
+
+void Lut::prepare(IPAContext &context,
+ [[maybe_unused]] const uint32_t frame,
+ [[maybe_unused]] IPAFrameContext &frameContext,
+ [[maybe_unused]] DebayerParams *params)
+{
+ /*
+ * Update the gamma table if needed. This means if black level changes
+ * and since the black level gets updated only if a lower value is
+ * observed, it's not permanently prone to minor fluctuations or
+ * rounding errors.
+ */
+ if (context.activeState.gamma.blackLevel != context.activeState.blc.level)
+ updateGammaTable(context);
+
+ auto &gains = context.activeState.gains;
+ auto &gammaTable = context.activeState.gamma.gammaTable;
+ const unsigned int gammaTableSize = gammaTable.size();
+
+ for (unsigned int i = 0; i < DebayerParams::kRGBLookupSize; i++) {
+ const double div = static_cast<double>(DebayerParams::kRGBLookupSize) /
+ gammaTableSize;
+ /* Apply gamma after gain! */
+ unsigned int idx;
+ idx = std::min({ static_cast<unsigned int>(i * gains.red / div),
+ gammaTableSize - 1 });
+ params->red[i] = gammaTable[idx];
+ idx = std::min({ static_cast<unsigned int>(i * gains.green / div),
+ gammaTableSize - 1 });
+ params->green[i] = gammaTable[idx];
+ idx = std::min({ static_cast<unsigned int>(i * gains.blue / div),
+ gammaTableSize - 1 });
+ params->blue[i] = gammaTable[idx];
+ }
+}
+
+REGISTER_IPA_ALGORITHM(Lut, "Lut")
+
+} /* namespace ipa::soft::algorithms */
+
+} /* namespace libcamera */
diff --git a/src/ipa/simple/algorithms/lut.h b/src/ipa/simple/algorithms/lut.h
new file mode 100644
index 00000000..b635987d
--- /dev/null
+++ b/src/ipa/simple/algorithms/lut.h
@@ -0,0 +1,34 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+/*
+ * Copyright (C) 2024, Red Hat Inc.
+ *
+ * Color lookup tables construction
+ */
+
+#pragma once
+
+#include "algorithm.h"
+
+namespace libcamera {
+
+namespace ipa::soft::algorithms {
+
+class Lut : public Algorithm
+{
+public:
+ Lut() = default;
+ ~Lut() = default;
+
+ int configure(IPAContext &context, const IPAConfigInfo &configInfo) override;
+ void prepare(IPAContext &context,
+ const uint32_t frame,
+ IPAFrameContext &frameContext,
+ DebayerParams *params) override;
+
+private:
+ void updateGammaTable(IPAContext &context);
+};
+
+} /* namespace ipa::soft::algorithms */
+
+} /* namespace libcamera */
diff --git a/src/ipa/simple/algorithms/meson.build b/src/ipa/simple/algorithms/meson.build
new file mode 100644
index 00000000..37a2eb53
--- /dev/null
+++ b/src/ipa/simple/algorithms/meson.build
@@ -0,0 +1,8 @@
+# SPDX-License-Identifier: CC0-1.0
+
+soft_simple_ipa_algorithms = files([
+ 'awb.cpp',
+ 'agc.cpp',
+ 'blc.cpp',
+ 'lut.cpp',
+])
generated by cgit v1.2.1 (git 2.18.0) at 2024-10-26 02:39:30 +0000