ipa: raspberrypi: Generalise the focus reporting code

Use the generalised focus statistics structure to compute the centre
window focus FoM value. This avoids needed to hard-code a specific
grid size.

Remove the focus reporting algorithm as the functionality is duplicated
by this bit of IPA code. Remove focus_status.h as it is no longer needed.

Signed-off-by: Naushir Patuck <naush@raspberrypi.com>
Reviewed-by: Jacopo Mondi <jacopo.mondi@ideasonboard.com>
Reviewed-by: David Plowman <david.plowman@raspberrypi.com>
Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com>

src/ipa/raspberrypi/controller/focus_status.h

@@ -1,20 +0,0 @@
-/* SPDX-License-Identifier: BSD-2-Clause */
-/*
- * Copyright (C) 2020, Raspberry Pi Ltd
- *
- * focus_status.h - focus measurement status
- */
-#pragma once
-
-#include <linux/bcm2835-isp.h>
-
-/*
- * The focus algorithm should post the following structure into the image's
- * "focus.status" metadata. Recall that it's only reporting focus (contrast)
- * measurements, it's not driving any kind of auto-focus algorithm!
- */
-
-struct FocusStatus {
-	unsigned int num;
-	uint32_t focusMeasures[FOCUS_REGIONS];
-};

src/ipa/raspberrypi/controller/rpi/af.h

@@ -28,7 +28,6 @@
  * "nuisance" scans. During each interval where PDAF is not working, only
  * ONE scan will be performed; CAF cannot track objects using CDAF alone.
  *
- * This algorithm is unrelated to "rpi.focus" which merely reports CDAF FoM.
  */
 
 namespace RPiController {

src/ipa/raspberrypi/controller/rpi/focus.cpp

@@ -1,49 +0,0 @@
-/* SPDX-License-Identifier: BSD-2-Clause */
-/*
- * Copyright (C) 2020, Raspberry Pi Ltd
- *
- * focus.cpp - focus algorithm
- */
-#include <stdint.h>
-
-#include <libcamera/base/log.h>
-
-#include "../focus_status.h"
-#include "focus.h"
-
-using namespace RPiController;
-using namespace libcamera;
-
-LOG_DEFINE_CATEGORY(RPiFocus)
-
-#define NAME "rpi.focus"
-
-Focus::Focus(Controller *controller)
-	: Algorithm(controller)
-{
-}
-
-char const *Focus::name() const
-{
-	return NAME;
-}
-
-void Focus::process(StatisticsPtr &stats, Metadata *imageMetadata)
-{
-	FocusStatus status;
-	for (unsigned int i = 0; i < stats->focusRegions.numRegions(); i++)
-		status.focusMeasures[i] = stats->focusRegions.get(i).val;
-	status.num = stats->focusRegions.numRegions();
-	imageMetadata->set("focus.status", status);
-
-	LOG(RPiFocus, Debug)
-		<< "Focus contrast measure: "
-		<< (status.focusMeasures[5] + status.focusMeasures[6]) / 10;
-}
-
-/* Register algorithm with the system. */
-static Algorithm *create(Controller *controller)
-{
-	return new Focus(controller);
-}
-static RegisterAlgorithm reg(NAME, &create);

src/ipa/raspberrypi/data/imx290.json

@@ -195,9 +195,6 @@
                     }
                 ]
             }
-        },
-        {
-            "rpi.focus": { }
         }
     ]
 }

src/ipa/raspberrypi/data/imx296.json

@@ -532,9 +532,6 @@
                 "strength": 1.0,
                 "limit": 0.18
             }
-        },
-        {
-            "rpi.focus": { }
         }
     ]
 }

src/ipa/raspberrypi/data/imx296_mono.json

@@ -228,9 +228,6 @@
                 "strength": 1.0,
                 "limit": 0.18
             }
-        },
-        {
-            "rpi.focus": { }
         }
     ]
 }

src/ipa/raspberrypi/data/imx477.json

@@ -513,9 +513,6 @@
         },
         {
             "rpi.sharpen": { }
-        },
-        {
-            "rpi.focus": { }
         }
     ]
 }

src/ipa/raspberrypi/data/imx477_noir.json

@@ -424,9 +424,6 @@
         },
         {
             "rpi.sharpen": { }
-        },
-        {
-            "rpi.focus": { }
         }
     ]
 }

src/ipa/raspberrypi/data/imx477_scientific.json

@@ -474,9 +474,6 @@
         },
         {
             "rpi.sharpen": { }
-        },
-        {
-            "rpi.focus": { }
         }
     ]
 }

src/ipa/raspberrypi/data/imx477_v1.json

@@ -511,9 +511,6 @@
         },
         {
             "rpi.sharpen": { }
-        },
-        {
-            "rpi.focus": { }
         }
     ]
 }

src/ipa/raspberrypi/data/imx708.json

@@ -512,9 +512,6 @@
         {
             "rpi.sharpen": { }
         },
-        {
-            "rpi.focus": { }
-        },
         {
             "rpi.af":
             {

src/ipa/raspberrypi/data/imx708_noir.json

@@ -512,9 +512,6 @@
         {
             "rpi.sharpen": { }
         },
-        {
-            "rpi.focus": { }
-        },
         {
             "rpi.af":
             {

src/ipa/raspberrypi/data/imx708_wide.json

@@ -403,9 +403,6 @@
         {
             "rpi.sharpen": { }
         },
-        {
-            "rpi.focus": { }
-        },
         {
             "rpi.af":
             {

src/ipa/raspberrypi/data/imx708_wide_noir.json

@@ -403,9 +403,6 @@
         {
             "rpi.sharpen": { }
         },
-        {
-            "rpi.focus": { }
-        },
         {
             "rpi.af":
             {

src/ipa/raspberrypi/meson.build

@@ -33,7 +33,6 @@ rpi_ipa_sources = files([
     'controller/rpi/awb.cpp',
     'controller/rpi/sharpen.cpp',
     'controller/rpi/black_level.cpp',
-    'controller/rpi/focus.cpp',
     'controller/rpi/geq.cpp',
     'controller/rpi/noise.cpp',
     'controller/rpi/lux.cpp',

src/ipa/raspberrypi/raspberrypi.cpp

@@ -50,7 +50,6 @@
 #include "denoise_algorithm.h"
 #include "denoise_status.h"
 #include "dpc_status.h"
-#include "focus_status.h"
 #include "geq_status.h"
 #include "lux_status.h"
 #include "metadata.h"
@@ -642,14 +641,28 @@ void IPARPi::reportMetadata(unsigned int ipaContext)
 					 static_cast<int32_t>(blackLevelStatus->blackLevelG),
 					 static_cast<int32_t>(blackLevelStatus->blackLevelB) });
 
-	FocusStatus *focusStatus = rpiMetadata.getLocked<FocusStatus>("focus.status");
+	RPiController::FocusRegions *focusStatus =
-	if (focusStatus && focusStatus->num == 12) {
+		rpiMetadata.getLocked<RPiController::FocusRegions>("focus.status");
+	if (focusStatus) {
 		/*
-		 * We get a 4x3 grid of regions by default. Calculate the average
+		 * Calculate the average FoM over the central (symmetric) positions
-		 * FoM over the central two positions to give an overall scene FoM.
+		 * to give an overall scene FoM. This can change later if it is
-		 * This can change later if it is not deemed suitable.
+		 * not deemed suitable.
 		 */
-		int32_t focusFoM = (focusStatus->focusMeasures[5] + focusStatus->focusMeasures[6]) / 2;
+		libcamera::Size size = focusStatus->size();
+		unsigned rows = size.height;
+		unsigned cols = size.width;
+
+		uint64_t sum = 0;
+		unsigned int numRegions = 0;
+		for (unsigned r = rows / 3; r < rows - rows / 3; ++r) {
+			for (unsigned c = cols / 4; c < cols - cols / 4; ++c) {
+				sum += focusStatus->get({ (int)c, (int)r }).val;
+				numRegions++;
+			}
+		}
+
+		uint32_t focusFoM = (sum / numRegions) >> 16;
 		libcameraMetadata_.set(controls::FocusFoM, focusFoM);
 	}
 
@@ -1428,7 +1441,6 @@ RPiController::StatisticsPtr IPARPi::fillStatistics(bcm2835_isp_stats *stats) co
 		statistics->focusRegions.set(i, { stats->focus_stats[i].contrast_val[1][1] / 1000,
 						  stats->focus_stats[i].contrast_val_num[1][1],
 						  stats->focus_stats[i].contrast_val_num[1][0] });
-
 	return statistics;
 }
 
@@ -1445,6 +1457,10 @@ void IPARPi::processStats(unsigned int bufferId, unsigned int ipaContext)
 	Span<uint8_t> mem = it->second.planes()[0];
 	bcm2835_isp_stats *stats = reinterpret_cast<bcm2835_isp_stats *>(mem.data());
 	RPiController::StatisticsPtr statistics = fillStatistics(stats);
+
+	/* Save the focus stats in the metadata structure to report out later. */
+	rpiMetadata_[ipaContext].set("focus.status", statistics->focusRegions);
+
 	helper_->process(statistics, rpiMetadata);
 	controller_.process(statistics, &rpiMetadata);