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libcamera: ipa: Add Soft IPA

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Define the Soft IPA main and event interfaces, add the Soft IPA
implementation.

The current src/ipa/meson.build assumes the IPA name to match the
pipeline name. For this reason "-Dipas=simple" is used for the
Soft IPA module.

Auto exposure/gain and AWB implementation by Dennis, Toon and Martti.

Auto exposure/gain targets a Mean Sample Value of 2.5 following
the MSV calculation algorithm from:
https://www.araa.asn.au/acra/acra2007/papers/paper84final.pdf

Use CameraSensorHelper to convert the analogue gain code read from the
camera sensor into real analogue gain value. In the future this makes
it possible to use faster AE/AGC algorithm. Right now the CameraSensorHelper
lets us use the full range of analogue gain values.

If there is no CameraSensorHelper for the camera sensor in use, a
warning log message is printed.

Tested-by: Bryan O'Donoghue <bryan.odonoghue@linaro.org> # sc8280xp Lenovo x13s
Tested-by: Pavel Machek <pavel@ucw.cz>
Reviewed-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Andrey Konovalov <andrey.konovalov@linaro.org>
Co-developed-by: Dennis Bonke <admin@dennisbonke.com>
Signed-off-by: Dennis Bonke <admin@dennisbonke.com>
Co-developed-by: Marttico <g.martti@gmail.com>
Signed-off-by: Marttico <g.martti@gmail.com>
Co-developed-by: Toon Langendam <t.langendam@gmail.com>
Signed-off-by: Toon Langendam <t.langendam@gmail.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
This commit is contained in:
Andrey Konovalov 2024-04-16 11:13:46 +02:00 • committed by Kieran Bingham
parent 3755d96648
commit c987946e43
10 changed files with 550 additions and 1 deletions
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393
src/ipa/simple/soft_simple.cpp Normal file
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/* SPDX-License-Identifier: LGPL-2.1-or-later */
/*
* Copyright (C) 2023, Linaro Ltd
*
* soft_simple.cpp - Simple Software Image Processing Algorithm module
*/
#include <sys/mman.h>
#include <linux/v4l2-controls.h>
#include <libcamera/base/file.h>
#include <libcamera/base/log.h>
#include <libcamera/base/shared_fd.h>
#include <libcamera/control_ids.h>
#include <libcamera/controls.h>
#include <libcamera/ipa/ipa_interface.h>
#include <libcamera/ipa/ipa_module_info.h>
#include <libcamera/ipa/soft_ipa_interface.h>
#include "libcamera/internal/software_isp/debayer_params.h"
#include "libcamera/internal/software_isp/swisp_stats.h"
#include "libcamera/internal/yaml_parser.h"
#include "libipa/camera_sensor_helper.h"
namespace libcamera {
LOG_DEFINE_CATEGORY(IPASoft)
namespace ipa::soft {
/*
* 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;
/*
* The below value 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;
class IPASoftSimple : public ipa::soft::IPASoftInterface
{
public:
IPASoftSimple()
: params_(nullptr), stats_(nullptr), ignoreUpdates_(0)
{
}
~IPASoftSimple();
int init(const IPASettings &settings,
const SharedFD &fdStats,
const SharedFD &fdParams,
const ControlInfoMap &sensorInfoMap) override;
int configure(const ControlInfoMap &sensorInfoMap) override;
int start() override;
void stop() override;
void processStats(const ControlList &sensorControls) override;
private:
void updateExposure(double exposureMSV);
DebayerParams *params_;
SwIspStats *stats_;
std::unique_ptr<CameraSensorHelper> camHelper_;
ControlInfoMap sensorInfoMap_;
int32_t exposureMin_, exposureMax_;
int32_t exposure_;
double againMin_, againMax_, againMinStep_;
double again_;
unsigned int ignoreUpdates_;
};
IPASoftSimple::~IPASoftSimple()
{
if (stats_)
munmap(stats_, sizeof(SwIspStats));
if (params_)
munmap(params_, sizeof(DebayerParams));
}
int IPASoftSimple::init(const IPASettings &settings,
const SharedFD &fdStats,
const SharedFD &fdParams,
const ControlInfoMap &sensorInfoMap)
{
camHelper_ = CameraSensorHelperFactoryBase::create(settings.sensorModel);
if (!camHelper_) {
LOG(IPASoft, Warning)
<< "Failed to create camera sensor helper for "
<< settings.sensorModel;
}
/* Load the tuning data file */
File file(settings.configurationFile);
if (!file.open(File::OpenModeFlag::ReadOnly)) {
int ret = file.error();
LOG(IPASoft, Error)
<< "Failed to open configuration file "
<< settings.configurationFile << ": " << strerror(-ret);
return ret;
}
std::unique_ptr<libcamera::YamlObject> data = YamlParser::parse(file);
if (!data)
return -EINVAL;
/* \todo Use the IPA configuration file for real. */
unsigned int version = (*data)["version"].get<uint32_t>(0);
LOG(IPASoft, Debug) << "Tuning file version " << version;
params_ = nullptr;
stats_ = nullptr;
if (!fdStats.isValid()) {
LOG(IPASoft, Error) << "Invalid Statistics handle";
return -ENODEV;
}
if (!fdParams.isValid()) {
LOG(IPASoft, Error) << "Invalid Parameters handle";
return -ENODEV;
}
{
void *mem = mmap(nullptr, sizeof(DebayerParams), PROT_WRITE,
MAP_SHARED, fdParams.get(), 0);
if (mem == MAP_FAILED) {
LOG(IPASoft, Error) << "Unable to map Parameters";
return -errno;
}
params_ = static_cast<DebayerParams *>(mem);
}
{
void *mem = mmap(nullptr, sizeof(SwIspStats), PROT_READ,
MAP_SHARED, fdStats.get(), 0);
if (mem == MAP_FAILED) {
LOG(IPASoft, Error) << "Unable to map Statistics";
return -errno;
}
stats_ = static_cast<SwIspStats *>(mem);
}
/*
* Check if the sensor driver supports the controls required by the
* Soft IPA.
* Don't save the min and max control values yet, as e.g. the limits
* for V4L2_CID_EXPOSURE depend on the configured sensor resolution.
*/
if (sensorInfoMap.find(V4L2_CID_EXPOSURE) == sensorInfoMap.end()) {
LOG(IPASoft, Error) << "Don't have exposure control";
return -EINVAL;
}
if (sensorInfoMap.find(V4L2_CID_ANALOGUE_GAIN) == sensorInfoMap.end()) {
LOG(IPASoft, Error) << "Don't have gain control";
return -EINVAL;
}
return 0;
}
int IPASoftSimple::configure(const ControlInfoMap &sensorInfoMap)
{
sensorInfoMap_ = sensorInfoMap;
const ControlInfo &exposureInfo = sensorInfoMap_.find(V4L2_CID_EXPOSURE)->second;
const ControlInfo &gainInfo = sensorInfoMap_.find(V4L2_CID_ANALOGUE_GAIN)->second;
exposureMin_ = exposureInfo.min().get<int32_t>();
exposureMax_ = exposureInfo.max().get<int32_t>();
if (!exposureMin_) {
LOG(IPASoft, Warning) << "Minimum exposure is zero, that can't be linear";
exposureMin_ = 1;
}
int32_t againMin = gainInfo.min().get<int32_t>();
int32_t againMax = gainInfo.max().get<int32_t>();
if (camHelper_) {
againMin_ = camHelper_->gain(againMin);
againMax_ = camHelper_->gain(againMax);
againMinStep_ = (againMax_ - againMin_) / 100.0;
} else {
/*
* The camera sensor gain (g) is usually not equal to the value written
* into the gain register (x). But the way how the AGC algorithm changes
* the gain value to make the total exposure closer to the optimum
* assumes that g(x) is not too far from linear function. If the minimal
* gain is 0, the g(x) is likely to be far from the linear, like
* g(x) = a / (b * x + c). To avoid unexpected changes to the gain by
* the AGC algorithm (abrupt near one edge, and very small near the
* other) we limit the range of the gain values used.
*/
againMax_ = againMax;
if (!againMin) {
LOG(IPASoft, Warning)
<< "Minimum gain is zero, that can't be linear";
againMin_ = std::min(100, againMin / 2 + againMax / 2);
}
againMinStep_ = 1.0;
}
LOG(IPASoft, Info) << "Exposure " << exposureMin_ << "-" << exposureMax_
<< ", gain " << againMin_ << "-" << againMax_
<< " (" << againMinStep_ << ")";
return 0;
}
int IPASoftSimple::start()
{
return 0;
}
void IPASoftSimple::stop()
{
}
void IPASoftSimple::processStats(const ControlList &sensorControls)
{
/*
* Calculate red and blue gains for AWB.
* Clamp max gain at 4.0, this also avoids 0 division.
*/
if (stats_->sumR_ <= stats_->sumG_ / 4)
params_->gainR = 1024;
else
params_->gainR = 256 * stats_->sumG_ / stats_->sumR_;
if (stats_->sumB_ <= stats_->sumG_ / 4)
params_->gainB = 1024;
else
params_->gainB = 256 * stats_->sumG_ / stats_->sumB_;
/* Green gain and gamma values are fixed */
params_->gainG = 256;
params_->gamma = 0.5;
setIspParams.emit();
/* \todo Switch to the libipa/algorithm.h API someday. */
/*
* AE / AGC, use 2 frames delay to make sure that the exposure and
* the gain set have applied to the camera sensor.
* \todo This could be handled better with DelayedControls.
*/
if (ignoreUpdates_ > 0) {
--ignoreUpdates_;
return;
}
/*
* Calculate Mean Sample Value (MSV) according to formula from:
* https://www.araa.asn.au/acra/acra2007/papers/paper84final.pdf
*/
constexpr unsigned int yHistValsPerBin =
SwIspStats::kYHistogramSize / kExposureBinsCount;
constexpr unsigned int yHistValsPerBinMod =
SwIspStats::kYHistogramSize /
(SwIspStats::kYHistogramSize % kExposureBinsCount + 1);
int exposureBins[kExposureBinsCount] = {};
unsigned int denom = 0;
unsigned int num = 0;
for (unsigned int i = 0; i < SwIspStats::kYHistogramSize; i++) {
unsigned int idx = (i - (i / yHistValsPerBinMod)) / yHistValsPerBin;
exposureBins[idx] += stats_->yHistogram[i];
}
for (unsigned int i = 0; i < kExposureBinsCount; i++) {
LOG(IPASoft, Debug) << i << ": " << exposureBins[i];
denom += exposureBins[i];
num += exposureBins[i] * (i + 1);
}
float exposureMSV = static_cast<float>(num) / denom;
/* Sanity check */
if (!sensorControls.contains(V4L2_CID_EXPOSURE) ||
!sensorControls.contains(V4L2_CID_ANALOGUE_GAIN)) {
LOG(IPASoft, Error) << "Control(s) missing";
return;
}
exposure_ = sensorControls.get(V4L2_CID_EXPOSURE).get<int32_t>();
int32_t again = sensorControls.get(V4L2_CID_ANALOGUE_GAIN).get<int32_t>();
again_ = camHelper_ ? camHelper_->gain(again) : again;
updateExposure(exposureMSV);
ControlList ctrls(sensorInfoMap_);
ctrls.set(V4L2_CID_EXPOSURE, exposure_);
ctrls.set(V4L2_CID_ANALOGUE_GAIN,
static_cast<int32_t>(camHelper_ ? camHelper_->gainCode(again_) : again_));
ignoreUpdates_ = 2;
setSensorControls.emit(ctrls);
LOG(IPASoft, Debug) << "exposureMSV " << exposureMSV
<< " exp " << exposure_ << " again " << again_
<< " gain R/B " << params_->gainR << "/" << params_->gainB;
}
void IPASoftSimple::updateExposure(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;
if (exposureMSV < kExposureOptimal - kExposureSatisfactory) {
next = exposure_ * kExpNumeratorUp / kExpDenominator;
if (next - exposure_ < 1)
exposure_ += 1;
else
exposure_ = next;
if (exposure_ >= exposureMax_) {
next = again_ * kExpNumeratorUp / kExpDenominator;
if (next - again_ < againMinStep_)
again_ += againMinStep_;
else
again_ = next;
}
}
if (exposureMSV > kExposureOptimal + kExposureSatisfactory) {
if (exposure_ == exposureMax_ && again_ > againMin_) {
next = again_ * kExpNumeratorDown / kExpDenominator;
if (again_ - next < againMinStep_)
again_ -= againMinStep_;
else
again_ = next;
} else {
next = exposure_ * kExpNumeratorDown / kExpDenominator;
if (exposure_ - next < 1)
exposure_ -= 1;
else
exposure_ = next;
}
}
exposure_ = std::clamp(exposure_, exposureMin_, exposureMax_);
again_ = std::clamp(again_, againMin_, againMax_);
}
} /* namespace ipa::soft */
/*
* External IPA module interface
*/
extern "C" {
const struct IPAModuleInfo ipaModuleInfo = {
IPA_MODULE_API_VERSION,
0,
"SimplePipelineHandler",
"simple",
};
IPAInterface *ipaCreate()
{
return new ipa::soft::IPASoftSimple();
}
} /* extern "C" */
} /* namespace libcamera */