new file mode 100644
@@ -0,0 +1,70 @@
+/* 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 = 256;
+
+ 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.
+ * Gain: 128 = 0.5, 256 = 1.0, 512 = 2.0, etc.
+ */
+ auto &gains = context.activeState.gains;
+ gains.red = sumR <= sumG / 4 ? 1024 : 256 * sumG / sumR;
+ gains.blue = sumB <= sumG / 4 ? 1024 : 256 * sumG / sumB;
+ /* Green gain is fixed to 256 */
+
+ LOG(IPASoftAwb, Debug) << "gain R/B " << gains.red << "/" << gains.blue;
+}
+
+REGISTER_IPA_ALGORITHM(Awb, "Awb")
+
+} /* namespace ipa::soft::algorithms */
+
+} /* namespace libcamera */
new file mode 100644
@@ -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 */
new file mode 100644
@@ -0,0 +1,83 @@
+/* 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 unsigned int div = static_cast<double>(DebayerParams::kRGBLookupSize) *
+ 256 / gammaTableSize;
+ /* Apply gamma after gain! */
+ unsigned int idx;
+ idx = std::min({ i * gains.red / div, gammaTableSize - 1 });
+ params->red[i] = gammaTable[idx];
+ idx = std::min({ i * gains.green / div, gammaTableSize - 1 });
+ params->green[i] = gammaTable[idx];
+ idx = std::min({ i * gains.blue / div, gammaTableSize - 1 });
+ params->blue[i] = gammaTable[idx];
+ }
+}
+
+REGISTER_IPA_ALGORITHM(Lut, "Lut")
+
+} /* namespace ipa::soft::algorithms */
+
+} /* namespace libcamera */
new file mode 100644
@@ -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 */
@@ -1,5 +1,7 @@
# SPDX-License-Identifier: CC0-1.0
soft_simple_ipa_algorithms = files([
+ 'awb.cpp',
'blc.cpp',
+ 'lut.cpp',
])
@@ -4,4 +4,6 @@
version: 1
algorithms:
- BlackLevel:
+ - Awb:
+ - Lut:
...
@@ -50,6 +50,11 @@ namespace libcamera::ipa::soft {
* \brief The current state of IPA algorithms
*/
+/**
+ * \var IPASessionConfiguration::gamma
+ * \brief Gamma value to be used in the raw image processing
+ */
+
/**
* \var IPAActiveState::black
* \brief Context for the Black Level algorithm
@@ -58,4 +63,29 @@ namespace libcamera::ipa::soft {
* \brief Current determined black level
*/
+/**
+ * \var IPAActiveState::gains
+ * \brief Context for gains in the Colors algorithm
+ *
+ * \var IPAActiveState::gains.red
+ * \brief Gain of red color
+ *
+ * \var IPAActiveState::gains.green
+ * \brief Gain of green color
+ *
+ * \var IPAActiveState::gains.blue
+ * \brief Gain of blue color
+ */
+
+/**
+ * \var IPAActiveState::gamma
+ * \brief Context for gamma in the Colors algorithm
+ *
+ * \var IPAActiveState::gamma.gammaTable
+ * \brief Computed gamma table
+ *
+ * \var IPAActiveState::gamma.blackLevel
+ * \brief Black level used for the gamma table computation
+ */
+
} /* namespace libcamera::ipa::soft */
@@ -7,6 +7,7 @@
#pragma once
+#include <array>
#include <stdint.h>
#include <libipa/fc_queue.h>
@@ -16,12 +17,25 @@ namespace libcamera {
namespace ipa::soft {
struct IPASessionConfiguration {
+ float gamma;
};
struct IPAActiveState {
struct {
uint8_t level;
} blc;
+
+ struct {
+ unsigned int red;
+ unsigned int green;
+ unsigned int blue;
+ } gains;
+
+ static constexpr unsigned int kGammaLookupSize = 1024;
+ struct {
+ std::array<double, kGammaLookupSize> gammaTable;
+ uint8_t blackLevel;
+ } gamma;
};
struct IPAFrameContext : public FrameContext {
@@ -5,8 +5,6 @@
* Simple Software Image Processing Algorithm module
*/
-#include <cmath>
-#include <numeric>
#include <stdint.h>
#include <sys/mman.h>
@@ -93,9 +91,6 @@ private:
std::unique_ptr<CameraSensorHelper> camHelper_;
ControlInfoMap sensorInfoMap_;
- static constexpr unsigned int kGammaLookupSize = 1024;
- std::array<uint8_t, kGammaLookupSize> gammaTable_;
- int lastBlackLevel_ = -1;
/* Local parameter storage */
struct IPAContext context_;
@@ -283,6 +278,7 @@ void IPASoftSimple::fillParamsBuffer(const uint32_t frame)
IPAFrameContext &frameContext = context_.frameContexts.get(frame);
for (auto const &algo : algorithms())
algo->prepare(context_, frame, frameContext, params_);
+ setIspParams.emit();
}
void IPASoftSimple::processStats(const uint32_t frame,
@@ -300,62 +296,6 @@ void IPASoftSimple::processStats(const uint32_t frame,
for (auto const &algo : algorithms())
algo->process(context_, frame, frameContext, stats_, metadata);
- 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.
- * Gain: 128 = 0.5, 256 = 1.0, 512 = 2.0, etc.
- */
- const unsigned int gainR = sumR <= sumG / 4 ? 1024 : 256 * sumG / sumR;
- const unsigned int gainB = sumB <= sumG / 4 ? 1024 : 256 * sumG / sumB;
- /* Green gain and gamma values are fixed */
- constexpr unsigned int gainG = 256;
-
- /* Update the gamma table if needed */
- if (blackLevel != lastBlackLevel_) {
- constexpr float gamma = 0.5;
- const unsigned int blackIndex = blackLevel * kGammaLookupSize / 256;
- std::fill(gammaTable_.begin(), gammaTable_.begin() + blackIndex, 0);
- const float divisor = kGammaLookupSize - blackIndex - 1.0;
- for (unsigned int i = blackIndex; i < kGammaLookupSize; i++)
- gammaTable_[i] = UINT8_MAX *
- std::pow((i - blackIndex) / divisor, gamma);
-
- lastBlackLevel_ = blackLevel;
- }
-
- for (unsigned int i = 0; i < DebayerParams::kRGBLookupSize; i++) {
- constexpr unsigned int div =
- DebayerParams::kRGBLookupSize * 256 / kGammaLookupSize;
- unsigned int idx;
-
- /* Apply gamma after gain! */
- idx = std::min({ i * gainR / div, (kGammaLookupSize - 1) });
- params_->red[i] = gammaTable_[idx];
-
- idx = std::min({ i * gainG / div, (kGammaLookupSize - 1) });
- params_->green[i] = gammaTable_[idx];
-
- idx = std::min({ i * gainB / div, (kGammaLookupSize - 1) });
- params_->blue[i] = gammaTable_[idx];
- }
-
- setIspParams.emit();
-
/* \todo Switch to the libipa/algorithm.h API someday. */
/*
@@ -372,6 +312,7 @@ void IPASoftSimple::processStats(const uint32_t frame,
* Calculate Mean Sample Value (MSV) according to formula from:
* https://www.araa.asn.au/acra/acra2007/papers/paper84final.pdf
*/
+ const uint8_t blackLevel = context_.activeState.blc.level;
const unsigned int blackLevelHistIdx =
blackLevel / (256 / SwIspStats::kYHistogramSize);
const unsigned int histogramSize =
@@ -421,7 +362,6 @@ void IPASoftSimple::processStats(const uint32_t frame,
LOG(IPASoft, Debug) << "exposureMSV " << exposureMSV
<< " exp " << exposure_ << " again " << again_
- << " gain R/B " << gainR << "/" << gainB
<< " black level " << static_cast<unsigned int>(blackLevel);
}