[libcamera-devel,RFC,2/3] libcamera: converter: add software converter

18981 diff mbox series

diff --git a/include/libcamera/internal/converter/converter_softw.h b/include/libcamera/internal/converter/converter_softw.h
new file mode 100644
index 00000000..aab1a650
--- /dev/null
+++ b/include/libcamera/internal/converter/converter_softw.h
@@ -0,0 +1,88 @@ 
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+/*
+ * Copyright (C) 2023, Linaro Ltd
+ *
+ * converter_softw.h - interface of software converter (runs 100% on CPU)
+ */
+
+#include <map>
+#include <tuple>
+#include <vector>
+
+#include <libcamera/base/log.h>
+#include <libcamera/base/signal.h>
+#include <libcamera/base/thread.h>
+
+#include <libcamera/pixel_format.h>
+
+#include "libcamera/internal/converter.h"
+
+namespace libcamera {
+
+class FrameBuffer;
+class Size;
+class SizeRange;
+struct StreamConfiguration;
+
+class SwConverter : public Converter
+{
+public:
+	SwConverter() : Converter() {}
+
+	int loadConfiguration([[maybe_unused]] const std::string &filename) { return 0; }
+	bool isValid() const { return true; }
+
+	std::vector<PixelFormat> formats(PixelFormat input);
+	SizeRange sizes(const Size &input);
+
+	std::tuple<unsigned int, unsigned int>
+	strideAndFrameSize(const PixelFormat &pixelFormat, const Size &size);
+
+	int configure(const StreamConfiguration &inputCfg,
+		      const std::vector<std::reference_wrapper<StreamConfiguration>> &outputCfg);
+	int exportBuffers(unsigned int ouput, unsigned int count,
+			  std::vector<std::unique_ptr<FrameBuffer>> *buffers);
+
+	void process(FrameBuffer *input, FrameBuffer *output);
+	int start();
+	void stop();
+
+	int queueBuffers(FrameBuffer *input,
+			 const std::map<unsigned int, FrameBuffer *> &outputs);
+
+private:
+	class Isp : public Object
+	{
+	public:
+		Isp(SwConverter *converter)
+			: converter_(converter) {}
+
+		int configure(const StreamConfiguration &inputCfg,
+			      const StreamConfiguration &outputCfg);
+		int exportBuffers(unsigned int count,
+				  std::vector<std::unique_ptr<FrameBuffer>> *buffers);
+		void process(FrameBuffer *input, FrameBuffer *output);
+		int start();
+		void stop();
+
+	private:
+		void debayer(uint8_t *dst, const uint8_t *src);
+
+		SwConverter *converter_;
+
+		Thread thread_;
+
+		unsigned int width_;
+		unsigned int height_;
+		unsigned int stride_;
+		Point red_shift_;
+
+		unsigned long rNumerat_, rDenomin_; /* red gain for AWB */
+		unsigned long bNumerat_, bDenomin_; /* blue gain for AWB */
+		unsigned long gNumerat_, gDenomin_; /* green gain for AWB */
+	};
+
+	std::unique_ptr<Isp> isp_;
+};
+
+} /* namespace libcamera */
diff --git a/include/libcamera/internal/converter/meson.build b/include/libcamera/internal/converter/meson.build
index 891e79e7..843a0483 100644
--- a/include/libcamera/internal/converter/meson.build
+++ b/include/libcamera/internal/converter/meson.build
@@ -1,5 +1,6 @@ 
 # SPDX-License-Identifier: CC0-1.0
 
 libcamera_internal_headers += files([
+    'converter_softw.h',
     'converter_v4l2_m2m.h',
 ])
diff --git a/src/libcamera/converter/converter_softw.cpp b/src/libcamera/converter/converter_softw.cpp
new file mode 100644
index 00000000..c66400b0
--- /dev/null
+++ b/src/libcamera/converter/converter_softw.cpp
@@ -0,0 +1,412 @@ 
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+/*
+ * Copyright (C) 2023, Linaro Ltd
+ *
+ * converter_softw.h - interface of software converter (runs 100% on CPU)
+ */
+
+#include "libcamera/internal/converter/converter_softw.h"
+
+#include <sys/mman.h>
+#include <sys/types.h>
+#include <tuple>
+#include <unistd.h>
+#include <vector>
+
+#include <libcamera/base/log.h>
+#include <libcamera/base/signal.h>
+#include <libcamera/base/thread.h>
+
+#include <libcamera/formats.h>
+#include <libcamera/geometry.h>
+#include <libcamera/pixel_format.h>
+#include <libcamera/stream.h>
+
+#include "libcamera/internal/bayer_format.h"
+#include "libcamera/internal/framebuffer.h"
+#include "libcamera/internal/mapped_framebuffer.h"
+
+namespace libcamera {
+
+LOG_DECLARE_CATEGORY(Converter)
+
+std::vector<PixelFormat> SwConverter::formats(PixelFormat input)
+{
+	std::vector<PixelFormat> pixelFormats;
+	BayerFormat inputFormat = BayerFormat::fromPixelFormat(input);
+
+	/* Only RAW10P is currently supported */
+	if (inputFormat.bitDepth == 10 && inputFormat.packing == BayerFormat::Packing::CSI2)
+		pixelFormats.push_back(formats::RGB888);
+
+	if (pixelFormats.empty())
+		LOG(Converter, Info)
+			<< "Unsupported input format " << input.toString();
+
+	return pixelFormats;
+}
+
+SizeRange SwConverter::sizes(const Size &input)
+{
+	if (input.width < 2 || input.height < 2) {
+		LOG(Converter, Error)
+			<< "Input format size too small: " << input.toString();
+		return {};
+	}
+
+	return SizeRange(Size(input.width - 2, input.height - 2));
+}
+
+std::tuple<unsigned int, unsigned int>
+SwConverter::strideAndFrameSize(const PixelFormat &pixelFormat,
+				const Size &size)
+{
+	/* Only RGB888 output is currently supported */
+	if (pixelFormat == formats::RGB888) {
+		int stride = size.width * 3;
+		return std::make_tuple(stride, stride * (size.height));
+	}
+
+	return std::make_tuple(0, 0);
+}
+
+int SwConverter::configure(const StreamConfiguration &inputCfg,
+			   const std::vector<std::reference_wrapper<StreamConfiguration>> &outputCfgs)
+{
+	if (outputCfgs.size() != 1) {
+		LOG(Converter, Error)
+			<< "Unsupported number of output streams: "
+			<< outputCfgs.size();
+		return -EINVAL;
+	}
+
+	isp_ = std::make_unique<SwConverter::Isp>(this);
+
+	return isp_->configure(inputCfg, outputCfgs[0]);
+}
+
+int SwConverter::Isp::configure(const StreamConfiguration &inputCfg,
+				const StreamConfiguration &outputCfg)
+{
+	BayerFormat bayerFormat =
+		BayerFormat::fromPixelFormat(inputCfg.pixelFormat);
+	width_ = inputCfg.size.width;
+	height_ = inputCfg.size.height;
+	stride_ = inputCfg.stride;
+
+	if (bayerFormat.bitDepth != 10 ||
+	    bayerFormat.packing != BayerFormat::Packing::CSI2 ||
+	    width_ < 2 || height_ < 2) {
+		LOG(Converter, Error) << "Input format "
+				      << inputCfg.size << "-"
+				      << inputCfg.pixelFormat
+				      << "not supported";
+		return -EINVAL;
+	}
+
+	switch (bayerFormat.order) {
+	case BayerFormat::BGGR:
+		red_shift_ = Point(0, 0);
+		break;
+	case BayerFormat::GBRG:
+		red_shift_ = Point(1, 0);
+		break;
+	case BayerFormat::GRBG:
+		red_shift_ = Point(0, 1);
+		break;
+	case BayerFormat::RGGB:
+	default:
+		red_shift_ = Point(1, 1);
+		break;
+	}
+
+	if (outputCfg.size.width != width_ - 2 ||
+	    outputCfg.size.height != height_ - 2 ||
+	    outputCfg.stride != (width_ - 2) * 3 ||
+	    outputCfg.pixelFormat != formats::RGB888) {
+		LOG(Converter, Error)
+			<< "Output format not supported";
+		return -EINVAL;
+	}
+
+	LOG(Converter, Info) << "SwConverter configuration: "
+			     << inputCfg.size << "-" << inputCfg.pixelFormat
+			     << " -> "
+			     << outputCfg.size << "-" << outputCfg.pixelFormat;
+
+	/* set r/g/b gains to 1.0 until frame data collected */
+	rNumerat_ = rDenomin_ = 1;
+	bNumerat_ = bDenomin_ = 1;
+	gNumerat_ = gDenomin_ = 1;
+
+	return 0;
+}
+
+int SwConverter::exportBuffers(unsigned int output, unsigned int count,
+			       std::vector<std::unique_ptr<FrameBuffer>> *buffers)
+{
+	/* single output for now */
+	if (output >= 1)
+		return -EINVAL;
+
+	return isp_->exportBuffers(count, buffers);
+}
+
+int SwConverter::Isp::exportBuffers(unsigned int count,
+				    std::vector<std::unique_ptr<FrameBuffer>> *buffers)
+{
+	/* V4L2_PIX_FMT_BGR24 aka 'BGR3' for output: */
+	unsigned int bufSize = (height_ - 2) * (width_ - 2) * 3;
+
+	for (unsigned int i = 0; i < count; i++) {
+		std::string name = "frame-" + std::to_string(i);
+
+		const int ispFd = memfd_create(name.c_str(), 0);
+		int ret = ftruncate(ispFd, bufSize);
+		if (ret < 0) {
+			LOG(Converter, Error) << "ftruncate() for memfd failed "
+						<< strerror(-ret);
+			return ret;
+		}
+
+		FrameBuffer::Plane outPlane;
+		outPlane.fd = SharedFD(std::move(ispFd));
+		outPlane.offset = 0;
+		outPlane.length = bufSize;
+
+		std::vector<FrameBuffer::Plane> planes{ outPlane };
+		buffers->emplace_back(std::make_unique<FrameBuffer>(std::move(planes)));
+	}
+
+	return count;
+}
+
+int SwConverter::Isp::start()
+{
+	moveToThread(&thread_);
+	thread_.start();
+	return 0;
+}
+
+void SwConverter::Isp::stop()
+{
+	thread_.exit();
+	thread_.wait();
+}
+
+int SwConverter::start()
+{
+	return isp_->start();
+}
+
+void SwConverter::stop()
+{
+	return isp_->stop();
+}
+
+int SwConverter::queueBuffers(FrameBuffer *input,
+			      const std::map<unsigned int, FrameBuffer *> &outputs)
+{
+	unsigned int mask = 0;
+
+	/*
+	 * Validate the outputs as a sanity check: at least one output is
+	 * required, all outputs must reference a valid stream and no two
+	 * outputs can reference the same stream.
+	 */
+	if (outputs.empty())
+		return -EINVAL;
+
+	for (auto [index, buffer] : outputs) {
+		if (!buffer)
+			return -EINVAL;
+		if (index >= 1) /* only single stream atm */
+			return -EINVAL;
+		if (mask & (1 << index))
+			return -EINVAL;
+
+		mask |= 1 << index;
+	}
+
+	process(input, outputs.at(0));
+
+	return 0;
+}
+
+void SwConverter::process(FrameBuffer *input, FrameBuffer *output)
+{
+	isp_->invokeMethod(&SwConverter::Isp::process,
+			   ConnectionTypeQueued, input, output);
+}
+
+void SwConverter::Isp::process(FrameBuffer *input, FrameBuffer *output)
+{
+	/* Copy metadata from the input buffer */
+	FrameMetadata &metadata = output->_d()->metadata();
+	metadata.status = input->metadata().status;
+	metadata.sequence = input->metadata().sequence;
+	metadata.timestamp = input->metadata().timestamp;
+
+	MappedFrameBuffer in(input, MappedFrameBuffer::MapFlag::Read);
+	MappedFrameBuffer out(output, MappedFrameBuffer::MapFlag::Write);
+	if (!in.isValid() || !out.isValid()) {
+		LOG(Converter, Error) << "mmap-ing buffer(s) failed";
+		metadata.status = FrameMetadata::FrameError;
+		converter_->outputBufferReady.emit(output);
+		converter_->inputBufferReady.emit(input);
+		return;
+	}
+
+	debayer(out.planes()[0].data(), in.planes()[0].data());
+	metadata.planes()[0].bytesused = out.planes()[0].size();
+
+	converter_->outputBufferReady.emit(output);
+	converter_->inputBufferReady.emit(input);
+}
+
+void SwConverter::Isp::debayer(uint8_t *dst, const uint8_t *src)
+{
+	/* RAW10P input format is assumed */
+
+	/* output buffer is in BGR24 format and is of (width-2)*(height-2) */
+
+	int w_out = width_ - 2;
+	int h_out = height_ - 2;
+
+	unsigned long sumR = 0;
+	unsigned long sumB = 0;
+	unsigned long sumG = 0;
+
+	for (int y = 0; y < h_out; y++) {
+		const uint8_t *pin_base = src + (y + 1) * stride_;
+		uint8_t *pout = dst + y * w_out * 3;
+		int phase_y = (y + red_shift_.y) % 2;
+
+		for (int x = 0; x < w_out; x++) {
+			int phase_x = (x + red_shift_.x) % 2;
+			int phase = 2 * phase_y + phase_x;
+
+			/* x part of the offset in the input buffer: */
+			int x_m1 = x + x / 4;		/* offset for (x-1) */
+			int x_0 = x + 1 + (x + 1) / 4;	/* offset for x */
+			int x_p1 = x + 2 + (x + 2) / 4;	/* offset for (x+1) */
+			/* the colour component value to write to the output */
+			unsigned val;
+
+			switch (phase) {
+			case 0: /* at R pixel */
+				/* blue: ((-1,-1)+(1,-1)+(-1,1)+(1,1)) / 4 */
+				val = ( *(pin_base + x_m1 - stride_)
+					+ *(pin_base + x_p1 - stride_)
+					+ *(pin_base + x_m1 + stride_)
+					+ *(pin_base + x_p1 + stride_) ) >> 2;
+				val = val * bNumerat_ / bDenomin_;
+				*pout++ = (uint8_t)std::min(val, 0xffU);
+				/* green: ((0,-1)+(-1,0)+(1,0)+(0,1)) / 4 */
+				val = ( *(pin_base + x_0 - stride_)
+					+ *(pin_base + x_p1)
+					+ *(pin_base + x_m1)
+					+ *(pin_base + x_0 + stride_) ) >> 2;
+				val = val * gNumerat_ / gDenomin_;
+				*pout++ = (uint8_t)std::min(val, 0xffU);
+				/* red: (0,0) */
+				val = *(pin_base + x_0);
+				sumR += val;
+				val = val * rNumerat_ / rDenomin_;
+				*pout++ = (uint8_t)std::min(val, 0xffU);
+				break;
+			case 1: /* at Gr pixel */
+				/* blue: ((0,-1) + (0,1)) / 2 */
+				val = ( *(pin_base + x_0 - stride_)
+					+ *(pin_base + x_0 + stride_) ) >> 1;
+				val = val * bNumerat_ / bDenomin_;
+				*pout++ = (uint8_t)std::min(val, 0xffU);
+				/* green: (0,0) */
+				val = *(pin_base + x_0);
+				sumG += val;
+				val = val * gNumerat_ / gDenomin_;
+				*pout++ = (uint8_t)std::min(val, 0xffU);
+				/* red: ((-1,0) + (1,0)) / 2 */
+				val = ( *(pin_base + x_m1)
+					+ *(pin_base + x_p1) ) >> 1;
+				val = val * rNumerat_ / rDenomin_;
+				*pout++ = (uint8_t)std::min(val, 0xffU);
+				break;
+			case 2: /* at Gb pixel */
+				/* blue: ((-1,0) + (1,0)) / 2 */
+				val = ( *(pin_base + x_m1)
+					+ *(pin_base + x_p1) ) >> 1;
+				val = val * bNumerat_ / bDenomin_;
+				*pout++ = (uint8_t)std::min(val, 0xffU);
+				/* green: (0,0) */
+				val = *(pin_base + x_0);
+				sumG += val;
+				val = val * gNumerat_ / gDenomin_;
+				*pout++ = (uint8_t)std::min(val, 0xffU);
+				/* red: ((0,-1) + (0,1)) / 2 */
+				val = ( *(pin_base + x_0 - stride_)
+					+ *(pin_base + x_0 + stride_) ) >> 1;
+				val = val * rNumerat_ / rDenomin_;
+				*pout++ = (uint8_t)std::min(val, 0xffU);
+				break;
+			default: /* at B pixel */
+				/* blue: (0,0) */
+				val = *(pin_base + x_0);
+				sumB += val;
+				val = val * bNumerat_ / bDenomin_;
+				*pout++ = (uint8_t)std::min(val, 0xffU);
+				/* green: ((0,-1)+(-1,0)+(1,0)+(0,1)) / 4 */
+				val = ( *(pin_base + x_0 - stride_)
+					+ *(pin_base + x_p1)
+					+ *(pin_base + x_m1)
+					+ *(pin_base + x_0 + stride_) ) >> 2;
+				val = val * gNumerat_ / gDenomin_;
+				*pout++ = (uint8_t)std::min(val, 0xffU);
+				/* red: ((-1,-1)+(1,-1)+(-1,1)+(1,1)) / 4 */
+				val = ( *(pin_base + x_m1 - stride_)
+					+ *(pin_base + x_p1 - stride_)
+					+ *(pin_base + x_m1 + stride_)
+					+ *(pin_base + x_p1 + stride_) ) >> 2;
+				val = val * rNumerat_ / rDenomin_;
+				*pout++ = (uint8_t)std::min(val, 0xffU);
+			}
+		}
+	}
+
+	/* calculate red and blue gains for simple AWB */
+	LOG(Converter, Debug) << "sumR = " << sumR
+			      << ", sumB = " << sumB << ", sumG = " << sumG;
+
+	sumG /= 2; /* the number of G pixels is twice as big vs R and B ones */
+
+	/* normalize red, blue, and green sums to fit into 22-bit value */
+	unsigned long fRed = sumR / 0x400000;
+	unsigned long fBlue = sumB / 0x400000;
+	unsigned long fGreen = sumG / 0x400000;
+	unsigned long fNorm = std::max({ 1UL, fRed, fBlue, fGreen });
+	sumR /= fNorm;
+	sumB /= fNorm;
+	sumG /= fNorm;
+
+	LOG(Converter, Debug) << "fNorm = " << fNorm;
+	LOG(Converter, Debug) << "Normalized: sumR = " << sumR
+			      << ", sumB= " << sumB << ", sumG = " << sumG;
+
+	/* make sure red/blue gains never exceed approximately 256 */
+	unsigned long minDenom;
+	rNumerat_ = (sumR + sumB + sumG) / 3;
+	minDenom = rNumerat_ / 0x100;
+	rDenomin_ = std::max(minDenom, sumR);
+	bNumerat_ = rNumerat_;
+	bDenomin_ = std::max(minDenom, sumB);
+	gNumerat_ = rNumerat_;
+	gDenomin_ = std::max(minDenom, sumG);
+
+	LOG(Converter, Debug) << "rGain = [ "
+			      << rNumerat_ << " / " << rDenomin_
+			      << " ], bGain = [ " << bNumerat_ << " / " << bDenomin_
+			      << " ], gGain = [ " << gNumerat_ << " / " << gDenomin_
+			      << " (minDenom = " << minDenom << ")";
+}
+
+} /* namespace libcamera */
diff --git a/src/libcamera/converter/meson.build b/src/libcamera/converter/meson.build
index 2aa72fe4..1f1e0ea4 100644
--- a/src/libcamera/converter/meson.build
+++ b/src/libcamera/converter/meson.build
@@ -1,5 +1,6 @@ 
 # SPDX-License-Identifier: CC0-1.0
 
 libcamera_sources += files([
-        'converter_v4l2_m2m.cpp'
+        'converter_softw.cpp',
+        'converter_v4l2_m2m.cpp',
 ])