[libcamera-devel] [PATCH v5 7/7] ipa: raspberrypi: agc: Fix digital gain calculation for manual mode
Naushir Patuck
naush at raspberrypi.com
Mon Oct 31 12:45:22 CET 2022
The digital gain calculation uses a total exposure value computed with the
current AGC state. However, this is wrong in the case of manual shutter/gain
controls, as the total exposure value used must be the value computed when the
AGC sent the manual shutter/gain controls to the pipeline handler to action.
To fix this, the IPA now adds the historical AgcStatus structure to the metadata
(tagged with "agc.delayed_status"). This historical AgcStatus structure contains
the total exposure value calculated when the AGC sent the manual shutter/gain
controls to the pipeline handler.
Signed-off-by: Naushir Patuck <naush at raspberrypi.com>
Reviewed-by: David Plowman <david.plowman at raspberrypi.com>
Tested-by: David Plowman <david.plowman at raspberrypi.com>
Reviewed-by: Kieran Bingham <kieran.bingham at ideasonboard.com>
---
src/ipa/raspberrypi/controller/rpi/agc.cpp | 10 ++++++++--
src/ipa/raspberrypi/raspberrypi.cpp | 11 +++++++++++
2 files changed, 19 insertions(+), 2 deletions(-)
diff --git a/src/ipa/raspberrypi/controller/rpi/agc.cpp b/src/ipa/raspberrypi/controller/rpi/agc.cpp
index bd54a639d637..b18bd7b5b19e 100644
--- a/src/ipa/raspberrypi/controller/rpi/agc.cpp
+++ b/src/ipa/raspberrypi/controller/rpi/agc.cpp
@@ -408,6 +408,12 @@ void Agc::switchMode(CameraMode const &cameraMode,
void Agc::prepare(Metadata *imageMetadata)
{
+ Duration totalExposureValue = status_.totalExposureValue;
+ AgcStatus delayedStatus;
+
+ if (!imageMetadata->get("agc.delayed_status", delayedStatus))
+ totalExposureValue = delayedStatus.totalExposureValue;
+
status_.digitalGain = 1.0;
fetchAwbStatus(imageMetadata); /* always fetch it so that Process knows it's been done */
@@ -418,8 +424,8 @@ void Agc::prepare(Metadata *imageMetadata)
Duration actualExposure = deviceStatus.shutterSpeed *
deviceStatus.analogueGain;
if (actualExposure) {
- status_.digitalGain = status_.totalExposureValue / actualExposure;
- LOG(RPiAgc, Debug) << "Want total exposure " << status_.totalExposureValue;
+ status_.digitalGain = totalExposureValue / actualExposure;
+ LOG(RPiAgc, Debug) << "Want total exposure " << totalExposureValue;
/*
* Never ask for a gain < 1.0, and also impose
* some upper limit. Make it customisable?
diff --git a/src/ipa/raspberrypi/raspberrypi.cpp b/src/ipa/raspberrypi/raspberrypi.cpp
index 194171a8bc96..7904f2b696dd 100644
--- a/src/ipa/raspberrypi/raspberrypi.cpp
+++ b/src/ipa/raspberrypi/raspberrypi.cpp
@@ -1028,6 +1028,17 @@ void IPARPi::prepareISP(const ISPConfig &data)
embeddedBuffer = it->second.planes()[0];
}
+ /*
+ * AGC wants to know the algorithm status from the time it actioned the
+ * sensor exposure/gain changes. So fetch it from the metadata list
+ * indexed by the IPA cookie returned, and put it in the current frame
+ * metadata.
+ */
+ AgcStatus agcStatus;
+ RPiController::Metadata &delayedMetadata = rpiMetadata_[data.delayContext];
+ if (!delayedMetadata.get<AgcStatus>("agc.status", agcStatus))
+ rpiMetadata.set("agc.delayed_status", agcStatus);
+
/*
* This may overwrite the DeviceStatus using values from the sensor
* metadata, and may also do additional custom processing.
--
2.25.1
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