[libcamera-devel] [PATCH v2 3/6] ipu3: Set statistics with the effective AE AiqResults

[Han-Lin Chen]

Set the statistics with the latest AE AiqResults which has the same
exposure time and analog gain. The patch reduces the AE haunting during
the converging process.

Signed-off-by: Han-Lin Chen <hanlinchen at chromium.org>
---
 aiq/aiq_input_parameters.cpp |  2 +-
 ipu3.cpp                     | 66 ++++++++++++++++++++++++++++++------
 2 files changed, 56 insertions(+), 12 deletions(-)

diff --git a/aiq/aiq_input_parameters.cpp b/aiq/aiq_input_parameters.cpp
index bc87b31..46553a6 100644
--- a/aiq/aiq_input_parameters.cpp
+++ b/aiq/aiq_input_parameters.cpp
@@ -130,7 +130,7 @@ AiqInputParameters &AiqInputParameters::operator=(const AiqInputParameters &othe
 
 void AiqInputParameters::setAeAwbAfDefaults()
 {
-	/*Ae Params */
+	/* Ae Params */
 	aeInputParams.num_exposures = NUM_EXPOSURES;
 	aeInputParams.frame_use = ia_aiq_frame_use_preview;
 	aeInputParams.flash_mode = ia_aiq_flash_mode_off;
diff --git a/ipu3.cpp b/ipu3.cpp
index 8126e9d..f463805 100644
--- a/ipu3.cpp
+++ b/ipu3.cpp
@@ -59,7 +59,8 @@ private:
 	void fillParams(unsigned int frame, ipu3_uapi_params *params);
 	void parseStatistics(unsigned int frame,
 			     int64_t frameTimestamp,
-			     const ipu3_uapi_stats_3a *stats);
+			     const ipu3_uapi_stats_3a *stats,
+			     const ControlList& sensorCtrls);
 
 	void setControls(unsigned int frame);
 
@@ -84,6 +85,7 @@ private:
 	/* Temporary storage until we have a FrameContext object / struct */
 	aiq::AiqInputParameters aiqInputParams_;
 	aiq::AiqResults results_;
+	aiq::AiqResultsRingBuffer resultsHistory_;
 
 	BinaryData aiqb_;
 	BinaryData nvm_;
@@ -282,6 +284,8 @@ int IPAIPU3::configure(const IPAConfigInfo &configInfo,
 	/* Upate the camera controls using the new sensor settings. */
 	updateControls(sensorInfo_, ctrls_, ipaControls);
 
+	resultsHistory_.Reset();
+
 	return 0;
 }
 
@@ -327,7 +331,10 @@ void IPAIPU3::processEvent(const IPU3Event &event)
 		const ipu3_uapi_stats_3a *stats =
 			reinterpret_cast<ipu3_uapi_stats_3a *>(mem.data());
 
-		parseStatistics(event.frame, event.frameTimestamp, stats);
+		parseStatistics(event.frame,
+				event.frameTimestamp,
+				stats,
+				event.sensorControls);
 		break;
 	}
 	case EventFillParams: {
@@ -374,14 +381,16 @@ void IPAIPU3::fillParams(unsigned int frame, ipu3_uapi_params *params)
 	*/
 
 	/* Run algorithms into/using this context structure */
-	if (frame % 10 == 0)
-		aiq_.run2a(frame, aiqInputParams_, results_);
+	aiq_.run2a(frame, aiqInputParams_, results_);
 
 	aic_.updateRuntimeParams(results_);
 	aic_.run(params);
 
 	exposure_ = results_.ae()->exposures[0].sensor_exposure->coarse_integration_time;
 	gain_ = results_.ae()->exposures[0].sensor_exposure->analog_gain_code_global;
+
+	resultsHistory_.Push(results_);
+
 	setControls(frame);
 
 	IPU3Action op;
@@ -392,7 +401,8 @@ void IPAIPU3::fillParams(unsigned int frame, ipu3_uapi_params *params)
 
 void IPAIPU3::parseStatistics(unsigned int frame,
 			      int64_t frameTimestamp,
-			      const ipu3_uapi_stats_3a *stats)
+			      const ipu3_uapi_stats_3a *stats,
+			      const ControlList& sensorCtrls)
 {
 	ControlList ctrls(controls::controls);
 
@@ -403,10 +413,43 @@ void IPAIPU3::parseStatistics(unsigned int frame,
 	 */
 
 	ASSERT (frameTimestamp > 0);
-	aiq_.setStatistics(frame, frameTimestamp, results_, stats);
+
+	/* Ae algorithm expects the statistics to be set with its corresponding
+	 * Ae result, i.e., the Ae result should match the exposure time and
+	 * analog gain with the the effective sensor controls of the statistics.
+	 * Search the required Ae result in the result history and combine it
+	 * with the latest result as the input to AIQ::setStatistics().
+	 */
+
+	int32_t effectiveExpo = 0;
+	int32_t effectiveGain = 0;
+	ControlValue ctrlValue;
+
+	ctrlValue = sensorCtrls.get(V4L2_CID_EXPOSURE);
+	if (!ctrlValue.isNone())
+		effectiveExpo = ctrlValue.get<int32_t>();
+
+	ctrlValue = sensorCtrls.get(V4L2_CID_ANALOGUE_GAIN);
+	if (!ctrlValue.isNone())
+		effectiveGain = ctrlValue.get<int32_t>();
+
+	auto pred = [effectiveExpo, effectiveGain] (aiq::AiqResults& result) {
+		ia_aiq_exposure_sensor_parameters* sensorExposure =
+			result.ae()->exposures[0].sensor_exposure;
+
+		return (effectiveExpo == sensorExposure->coarse_integration_time ||
+			effectiveGain == sensorExposure->analog_gain_code_global);
+	};
+	aiq::AiqResults& aeMatchedResults = resultsHistory_.searchBackward(pred, results_);
+
+	aiq::AiqResults combinedResults = results_;
+	combinedResults.setAe(aeMatchedResults.ae());
+
+	/* Aiq library expects timestamp in microseconds */
+	aiq_.setStatistics(frame, (frameTimestamp / 1000), combinedResults, stats);
 
 	/* Set frame durations from exposure results */
-	ia_aiq_exposure_sensor_parameters *sensorExposure = results_.ae()->exposures->sensor_exposure;
+	ia_aiq_exposure_sensor_parameters *sensorExposure = combinedResults.ae()->exposures->sensor_exposure;
 	int64_t frameDuration = (sensorExposure->line_length_pixels * sensorExposure->frame_length_lines) /
 				(sensorInfo_.pixelRate / 1e6);
 	ctrls.set(controls::FrameDuration, frameDuration);
@@ -423,10 +466,11 @@ void IPAIPU3::setControls(unsigned int frame)
 	IPU3Action op;
 	op.op = ActionSetSensorControls;
 
-	ControlList ctrls(ctrls_);
-	ctrls.set(V4L2_CID_EXPOSURE, static_cast<int32_t>(exposure_));
-	ctrls.set(V4L2_CID_ANALOGUE_GAIN, static_cast<int32_t>(gain_));
-	op.controls = ctrls;
+	ControlList sensorCtrls(ctrls_);
+	sensorCtrls.set(V4L2_CID_EXPOSURE, static_cast<int32_t>(exposure_));
+	sensorCtrls.set(V4L2_CID_ANALOGUE_GAIN, static_cast<int32_t>(gain_));
+
+	op.sensorControls = sensorCtrls;
 
 	queueFrameAction.emit(frame, op);
 }
-- 
2.33.1.1089.g2158813163f-goog