tvl-depot/users/flokli/ipu6-softisp/libcamera/0018-libcamera-debayer_cpu-Add-BGR888-output-support.patch

From b835b2c90785ee02bc98888bf165713d16c24cc4 Mon Sep 17 00:00:00 2001
From: Hans de Goede <hdegoede@redhat.com>
Date: Mon, 18 Dec 2023 19:21:07 +0100
Subject: [PATCH 18/25] libcamera: debayer_cpu: Add BGR888 output support

BGR888 is RGB888 with the red and blue pixels swapped, adjust
the debayering to swap the red and blue pixels in the bayer pattern
to add support for writing formats::BGR888.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Tested-by: Bryan O'Donoghue <bryan.odonoghue@linaro.org> # sc8280xp Lenovo x13s
Tested-by: Pavel Machek <pavel@ucw.cz>
---
 .../internal/software_isp/debayer_cpu.h       |  1 +
 src/libcamera/software_isp/debayer_cpu.cpp    | 43 ++++++++++++++++---
 2 files changed, 39 insertions(+), 5 deletions(-)

diff --git a/include/libcamera/internal/software_isp/debayer_cpu.h b/include/libcamera/internal/software_isp/debayer_cpu.h
index 1147b368..bdeab7c0 100644
--- a/include/libcamera/internal/software_isp/debayer_cpu.h
+++ b/include/libcamera/internal/software_isp/debayer_cpu.h
@@ -133,6 +133,7 @@ private:
 	unsigned int lineBufferIndex_;
 	unsigned int x_shift_; /* Offset of 0/1 applied to window_.x */
 	bool enableInputMemcpy_;
+	bool swapRedBlueGains_;
 	float gamma_correction_;
 	int measuredFrames_;
 	int64_t frameProcessTime_;
diff --git a/src/libcamera/software_isp/debayer_cpu.cpp b/src/libcamera/software_isp/debayer_cpu.cpp
index 7b7623b7..0edea4d3 100644
--- a/src/libcamera/software_isp/debayer_cpu.cpp
+++ b/src/libcamera/software_isp/debayer_cpu.cpp
@@ -245,7 +245,7 @@ int DebayerCpu::getInputConfig(PixelFormat inputFormat, DebayerInputConfig &conf
 		config.bpp = (bayerFormat.bitDepth + 7) & ~7;
 		config.patternSize.width = 2;
 		config.patternSize.height = 2;
-		config.outputFormats = std::vector<PixelFormat>({ formats::RGB888 });
+		config.outputFormats = std::vector<PixelFormat>({ formats::RGB888, formats::BGR888 });
 		return 0;
 	}
 
@@ -255,7 +255,7 @@ int DebayerCpu::getInputConfig(PixelFormat inputFormat, DebayerInputConfig &conf
 		config.bpp = 10;
 		config.patternSize.width = 4; /* 5 bytes per *4* pixels */
 		config.patternSize.height = 2;
-		config.outputFormats = std::vector<PixelFormat>({ formats::RGB888 });
+		config.outputFormats = std::vector<PixelFormat>({ formats::RGB888, formats::BGR888 });
 		return 0;
 	}
 
@@ -266,7 +266,7 @@ int DebayerCpu::getInputConfig(PixelFormat inputFormat, DebayerInputConfig &conf
 
 int DebayerCpu::getOutputConfig(PixelFormat outputFormat, DebayerOutputConfig &config)
 {
-	if (outputFormat == formats::RGB888) {
+	if (outputFormat == formats::RGB888 || outputFormat == formats::BGR888) {
 		config.bpp = 24;
 		return 0;
 	}
@@ -302,12 +302,41 @@ int DebayerCpu::setupStandardBayerOrder(BayerFormat::Order order)
 	return 0;
 }
 
-/* TODO: this ignores outputFormat since there is only 1 supported outputFormat for now */
-int DebayerCpu::setDebayerFunctions(PixelFormat inputFormat, [[maybe_unused]] PixelFormat outputFormat)
+int DebayerCpu::setDebayerFunctions(PixelFormat inputFormat, PixelFormat outputFormat)
 {
 	BayerFormat bayerFormat =
 		BayerFormat::fromPixelFormat(inputFormat);
 
+	swapRedBlueGains_ = false;
+
+	switch (outputFormat) {
+	case formats::RGB888:
+		break;
+	case formats::BGR888:
+		/* Swap R and B in bayer order to generate BGR888 instead of RGB888 */
+		swapRedBlueGains_ = true;
+
+		switch (bayerFormat.order) {
+		case BayerFormat::BGGR:
+			bayerFormat.order = BayerFormat::RGGB;
+			break;
+		case BayerFormat::GBRG:
+			bayerFormat.order = BayerFormat::GRBG;
+			break;
+		case BayerFormat::GRBG:
+			bayerFormat.order = BayerFormat::GBRG;
+			break;
+		case BayerFormat::RGGB:
+			bayerFormat.order = BayerFormat::BGGR;
+			break;
+		default:
+			goto invalid_fmt;
+		}
+		break;
+	default:
+		goto invalid_fmt;
+	}
+
 	x_shift_ = 0;
 
 	if ((bayerFormat.bitDepth == 8 || bayerFormat.bitDepth == 10 || bayerFormat.bitDepth == 12) &&
@@ -355,6 +384,7 @@ int DebayerCpu::setDebayerFunctions(PixelFormat inputFormat, [[maybe_unused]] Pi
 		}
 	}
 
+invalid_fmt:
 	LOG(Debayer, Error) << "Unsupported input output format combination";
 	return -EINVAL;
 }
@@ -594,6 +624,9 @@ void DebayerCpu::process(FrameBuffer *input, FrameBuffer *output, DebayerParams
 		gamma_correction_ = params.gamma;
 	}
 
+	if (swapRedBlueGains_)
+		std::swap(params.gainR, params.gainB);
+
 	for (int i = 0; i < 256; i++) {
 		int idx;
 
-- 
2.43.0