@@ -39,6 +39,7 @@ int Agc::read(const libcamera::YamlObject ¶ms)
*/
if (!params.contains("channels")) {
LOG(RPiAgc, Debug) << "Single channel only";
+ channelTotalExposures_.resize(1, 0s);
channelData_.emplace_back();
return channelData_.back().channel.read(params, getHardwareConfig());
}
@@ -58,6 +59,8 @@ int Agc::read(const libcamera::YamlObject ¶ms)
return -1;
}
+ channelTotalExposures_.resize(channelData_.size(), 0s);
+
return 0;
}
@@ -236,16 +239,22 @@ static void getDelayedChannelIndex(Metadata *metadata, const char *message, unsi
}
}
-static void setCurrentChannelIndex(Metadata *metadata, const char *message, unsigned int channelIndex)
+static libcamera::utils::Duration
+setCurrentChannelIndexGetExposure(Metadata *metadata, const char *message, unsigned int channelIndex)
{
std::unique_lock<RPiController::Metadata> lock(*metadata);
AgcStatus *status = metadata->getLocked<AgcStatus>("agc.status");
- if (status)
+ libcamera::utils::Duration dur = 0s;
+
+ if (status) {
status->channel = channelIndex;
- else {
+ dur = status->totalExposureValue;
+ } else {
/* This does happen at startup, otherwise it would be a Warning or Error. */
LOG(RPiAgc, Debug) << message;
}
+
+ return dur;
}
void Agc::prepare(Metadata *imageMetadata)
@@ -310,8 +319,11 @@ void Agc::process(StatisticsPtr &stats, Metadata *imageMetadata)
LOG(RPiAgc, Debug) << "process: channel " << channelIndex << " not seen yet";
}
- channelData.channel.process(stats, deviceStatus, imageMetadata);
- setCurrentChannelIndex(imageMetadata, "process: no AGC status found", channelIndex);
+ channelData.channel.process(stats, deviceStatus, imageMetadata, channelTotalExposures_);
+ auto dur = setCurrentChannelIndexGetExposure(imageMetadata, "process: no AGC status found",
+ channelIndex);
+ if (dur)
+ channelTotalExposures_[channelIndex] = dur;
/* And onto the next channel for the next call. */
index_ = (index_ + 1) % activeChannels_.size();
@@ -55,6 +55,7 @@ private:
std::vector<AgcChannelData> channelData_;
std::vector<unsigned int> activeChannels_;
unsigned int index_; /* index into the activeChannels_ */
+ AgcChannelTotalExposures channelTotalExposures_;
};
} /* namespace RPiController */
@@ -493,7 +493,9 @@ void AgcChannel::prepare(Metadata *imageMetadata)
}
}
-void AgcChannel::process(StatisticsPtr &stats, DeviceStatus const &deviceStatus, Metadata *imageMetadata)
+void AgcChannel::process(StatisticsPtr &stats, DeviceStatus const &deviceStatus,
+ Metadata *imageMetadata,
+ const AgcChannelTotalExposures &channelTotalExposures)
{
frameCount_++;
/*
@@ -512,12 +514,17 @@ void AgcChannel::process(StatisticsPtr &stats, DeviceStatus const &deviceStatus,
computeTargetExposure(gain);
/* The results have to be filtered so as not to change too rapidly. */
filterExposure();
+ /*
+ * We may be asked to limit the exposure using other channels. If another channel
+ * determines our upper bound we may want to know this later.
+ */
+ bool channelBound = applyChannelConstraints(channelTotalExposures);
/*
* Some of the exposure has to be applied as digital gain, so work out
- * what that is. This function also tells us whether it's decided to
- * "desaturate" the image more quickly.
+ * what that is. It also tells us whether it's trying to desaturate the image
+ * more quickly, which can only happen when another channel is not limiting us.
*/
- bool desaturate = applyDigitalGain(gain, targetY);
+ bool desaturate = applyDigitalGain(gain, targetY, channelBound);
/*
* The last thing is to divide up the exposure value into a shutter time
* and analogue gain, according to the current exposure mode.
@@ -794,7 +801,44 @@ void AgcChannel::computeTargetExposure(double gain)
LOG(RPiAgc, Debug) << "Target totalExposure " << target_.totalExposure;
}
-bool AgcChannel::applyDigitalGain(double gain, double targetY)
+bool AgcChannel::applyChannelConstraints(const AgcChannelTotalExposures &channelTotalExposures)
+{
+ bool channelBound = false;
+ LOG(RPiAgc, Debug)
+ << "Total exposure before channel constraints " << filtered_.totalExposure;
+
+ for (const auto &constraint : config_.channelConstraints) {
+ LOG(RPiAgc, Debug)
+ << "Check constraint: channel " << constraint.channel << " bound "
+ << (constraint.bound == AgcChannelConstraint::Bound::UPPER ? "UPPER" : "LOWER")
+ << " factor " << constraint.factor;
+ if (constraint.channel >= channelTotalExposures.size() ||
+ !channelTotalExposures[constraint.channel]) {
+ LOG(RPiAgc, Debug) << "no such channel or no exposure available- skipped";
+ continue;
+ }
+
+ libcamera::utils::Duration limitExposure =
+ channelTotalExposures[constraint.channel] * constraint.factor;
+ LOG(RPiAgc, Debug) << "Limit exposure " << limitExposure;
+ if ((constraint.bound == AgcChannelConstraint::Bound::UPPER &&
+ filtered_.totalExposure > limitExposure) ||
+ (constraint.bound == AgcChannelConstraint::Bound::LOWER &&
+ filtered_.totalExposure < limitExposure)) {
+ filtered_.totalExposure = limitExposure;
+ LOG(RPiAgc, Debug) << "Constraint applies";
+ channelBound = true;
+ } else
+ LOG(RPiAgc, Debug) << "Constraint does not apply";
+ }
+
+ LOG(RPiAgc, Debug)
+ << "Total exposure after channel constraints " << filtered_.totalExposure;
+
+ return channelBound;
+}
+
+bool AgcChannel::applyDigitalGain(double gain, double targetY, bool channelBound)
{
double minColourGain = std::min({ awb_.gainR, awb_.gainG, awb_.gainB, 1.0 });
ASSERT(minColourGain != 0.0);
@@ -814,8 +858,8 @@ bool AgcChannel::applyDigitalGain(double gain, double targetY)
* quickly (and we then approach the correct value more quickly from
* below).
*/
- bool desaturate = targetY > config_.fastReduceThreshold &&
- gain < sqrt(targetY);
+ bool desaturate = !channelBound &&
+ targetY > config_.fastReduceThreshold && gain < sqrt(targetY);
if (desaturate)
dg /= config_.fastReduceThreshold;
LOG(RPiAgc, Debug) << "Digital gain " << dg << " desaturate? " << desaturate;
@@ -21,6 +21,8 @@
namespace RPiController {
+using AgcChannelTotalExposures = std::vector<libcamera::utils::Duration>;
+
struct AgcMeteringMode {
std::vector<double> weights;
int read(const libcamera::YamlObject ¶ms);
@@ -95,7 +97,8 @@ public:
void disableAuto();
void switchMode(CameraMode const &cameraMode, Metadata *metadata);
void prepare(Metadata *imageMetadata);
- void process(StatisticsPtr &stats, DeviceStatus const &deviceStatus, Metadata *imageMetadata);
+ void process(StatisticsPtr &stats, DeviceStatus const &deviceStatus, Metadata *imageMetadata,
+ const AgcChannelTotalExposures &channelTotalExposures);
private:
bool updateLockStatus(DeviceStatus const &deviceStatus);
@@ -107,7 +110,8 @@ private:
double &gain, double &targetY);
void computeTargetExposure(double gain);
void filterExposure();
- bool applyDigitalGain(double gain, double targetY);
+ bool applyChannelConstraints(const AgcChannelTotalExposures &channelTotalExposures);
+ bool applyDigitalGain(double gain, double targetY, bool channelBound);
void divideUpExposure();
void writeAndFinish(Metadata *imageMetadata, bool desaturate);
libcamera::utils::Duration limitShutter(libcamera::utils::Duration shutter);