[libcamera-devel] [PATCH v2 16/18] libcamera: swstats_cpu: Add support for 8 and 10 bpp unpacked bayer input

[Hans de Goede]

Add support for 8 and 10 bpp unpacked bayer input for all 4 standard
bayer orders.

Signed-off-by: Hans de Goede <hdegoede at redhat.com>
Tested-by: Bryan O'Donoghue <bryan.odonoghue at linaro.org> # sc8280xp Lenovo x13s
Tested-by: Pavel Machek <pavel at ucw.cz>
---
 .../internal/software_isp/swstats_cpu.h       |  7 ++
 src/libcamera/software_isp/swstats_cpu.cpp    | 97 +++++++++++++++++++
 2 files changed, 104 insertions(+)

diff --git a/include/libcamera/internal/software_isp/swstats_cpu.h b/include/libcamera/internal/software_isp/swstats_cpu.h
index 8bb86e98..3410753c 100644
--- a/include/libcamera/internal/software_isp/swstats_cpu.h
+++ b/include/libcamera/internal/software_isp/swstats_cpu.h
@@ -11,6 +11,7 @@
 
 #pragma once
 
+#include "libcamera/internal/bayer_format.h"
 #include "libcamera/internal/shared_mem_object.h"
 #include "libcamera/internal/software_isp/swisp_stats.h"
 #include "libcamera/internal/software_isp/swstats.h"
@@ -31,6 +32,12 @@ public:
 	const SharedFD &getStatsFD() { return sharedStats_.fd(); }
 	int configure(const StreamConfiguration &inputCfg);
 private:
+	int setupStandardBayerOrder(BayerFormat::Order order);
+	/* Bayer 8 bpp unpacked */
+	void statsBGGR8Line0(const uint8_t *src[]);
+	/* Bayer 10 bpp unpacked */
+	void statsBGGR10Line0(const uint8_t *src[]);
+	/* Bayer 10 bpp packed */
 	void statsBGGR10PLine0(const uint8_t *src[]);
 	void statsGBRG10PLine0(const uint8_t *src[]);
 	void resetStats(void);
diff --git a/src/libcamera/software_isp/swstats_cpu.cpp b/src/libcamera/software_isp/swstats_cpu.cpp
index 59453d07..6bd78860 100644
--- a/src/libcamera/software_isp/swstats_cpu.cpp
+++ b/src/libcamera/software_isp/swstats_cpu.cpp
@@ -59,6 +59,57 @@ static const unsigned int BLUE_Y_MUL = 29; /* 0.11 * 256 */
 	stats_.sumG_ += sumG;            \
 	stats_.sumB_ += sumB;
 
+void SwStatsCpu::statsBGGR8Line0(const uint8_t *src[])
+{
+	const uint8_t *src0 = src[1] + window_.x;
+	const uint8_t *src1 = src[2] + window_.x;
+
+	SWISP_LINARO_START_LINE_STATS(uint8_t)
+
+	if (swap_lines_)
+		std::swap(src0, src1);
+
+	/* x += 4 sample every other 2x2 block */
+	for (int x = 0; x < (int)window_.width; x += 4) {
+		b = src0[x];
+		g = src0[x + 1];
+		g2 = src1[x];
+		r = src1[x + 1];
+
+		g = (g + g2) / 2;
+
+		SWISP_LINARO_ACCUMULATE_LINE_STATS(1)
+	}
+
+	SWISP_LINARO_FINISH_LINE_STATS()
+}
+
+void SwStatsCpu::statsBGGR10Line0(const uint8_t *src[])
+{
+	const uint16_t *src0 = (const uint16_t *)src[1] + window_.x;
+	const uint16_t *src1 = (const uint16_t *)src[2] + window_.x;
+
+	SWISP_LINARO_START_LINE_STATS(uint16_t)
+
+	if (swap_lines_)
+		std::swap(src0, src1);
+
+	/* x += 4 sample every other 2x2 block */
+	for (int x = 0; x < (int)window_.width; x += 4) {
+		b = src0[x];
+		g = src0[x + 1];
+		g2 = src1[x];
+		r = src1[x + 1];
+
+		g = (g + g2) / 2;
+
+		/* divide Y by 4 for 10 -> 8 bpp value */
+		SWISP_LINARO_ACCUMULATE_LINE_STATS(4)
+	}
+
+	SWISP_LINARO_FINISH_LINE_STATS()
+}
+
 static inline __attribute__((always_inline)) void
 statsBayer10P(const int width, const uint8_t *src0, const uint8_t *src1, bool bggr, SwIspStats &stats_)
 {
@@ -124,6 +175,39 @@ void SwStatsCpu::finishStats(void)
 	statsReady.emit(0);
 }
 
+/*
+ * Check if order is a standard Bayer order and setup x_shift_ and swap_lines_
+ * so that a single BGGR stats function can be used for all 4 standard orders.
+ */
+int SwStatsCpu::setupStandardBayerOrder(BayerFormat::Order order)
+{
+	switch (order) {
+	case BayerFormat::BGGR:
+		x_shift_ = 0;
+		swap_lines_ = false;
+		break;
+	case BayerFormat::GBRG:
+		x_shift_ = 1; /* BGGR -> GBRG */
+		swap_lines_ = false;
+		break;
+	case BayerFormat::GRBG:
+		x_shift_ = 0;
+		swap_lines_ = true; /* BGGR -> GRBG */
+		break;
+	case BayerFormat::RGGB:
+		x_shift_ = 1; /* BGGR -> GBRG */
+		swap_lines_ = true; /* GBRG -> RGGB */
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	patternSize_.height = 2;
+	patternSize_.width = 2;
+	y_skip_mask_ = 0x02; /* Skip every 3th and 4th line */
+	return 0;
+}
+
 int SwStatsCpu::configure(const StreamConfiguration &inputCfg)
 {
 	BayerFormat bayerFormat =
@@ -132,6 +216,19 @@ int SwStatsCpu::configure(const StreamConfiguration &inputCfg)
 	startFrame_ = (SwStats::statsVoidFn)&SwStatsCpu::resetStats;
 	finishFrame_ = (SwStats::statsVoidFn)&SwStatsCpu::finishStats;
 
+	if (bayerFormat.packing == BayerFormat::Packing::None &&
+	    setupStandardBayerOrder(bayerFormat.order) == 0) {
+		bpp_ = (bayerFormat.bitDepth + 7) & ~7;
+		switch (bayerFormat.bitDepth) {
+		case 8:
+			stats0_ = (SwStats::statsProcessFn)&SwStatsCpu::statsBGGR8Line0;
+			return 0;
+		case 10:
+			stats0_ = (SwStats::statsProcessFn)&SwStatsCpu::statsBGGR10Line0;
+			return 0;
+		}
+	}
+
 	if (bayerFormat.bitDepth == 10 &&
 	    bayerFormat.packing == BayerFormat::Packing::CSI2) {
 		bpp_ = 10;
-- 
2.43.0