[libcamera-devel] [PATCH v2 12/12] android: camera_device: Support MJPEG stream construction

Kieran Bingham kieran.bingham at ideasonboard.com
Mon Aug 3 18:18:16 CEST 2020


MJPEG streams must be created referencing a libcamera stream.
This stream may already be provided by the request configuration,
in which case the existing stream is utilised.

If no compatible stream is available to encode, a new stream is requested
from the libcamera configuration.

Signed-off-by: Kieran Bingham <kieran.bingham at ideasonboard.com>
---

This is probably the main patch holding me up at the moment, as there
are just so many bits I'm not happy with.

 - Clean up the "Fill in the JPEG blob header."
 - Added streams for different MPEG requirements don't have their own
   buffers (only just realised that today, so I think we should just
   pull that out for a first integration)
 - JPEG compression should run in a thread.
 - I really dislike the current mapping between camera3_stream to
   libcamera stream with the index
 - The JPEG compressor is not currently destructed.
   I was going to handle that by moving the CameraStream to a class
   which would then destroy the compressor in it's destructor - but that
   hasn't gone down that path, maybe it still should.
 - Metadata additions are horrible to keep in sync (especially through
   rebases)
 - More stuff ;-)

Anyway, here's the current WIP - and it works ... so hey that's a bonus
  ;-)




 src/android/camera_device.cpp | 202 +++++++++++++++++++++++++++++++++-
 src/android/camera_device.h   |   8 ++
 2 files changed, 204 insertions(+), 6 deletions(-)

diff --git a/src/android/camera_device.cpp b/src/android/camera_device.cpp
index e23ab055d012..42b08cfc5fed 100644
--- a/src/android/camera_device.cpp
+++ b/src/android/camera_device.cpp
@@ -8,6 +8,7 @@
 #include "camera_device.h"
 #include "camera_ops.h"
 
+#include <sys/mman.h>
 #include <tuple>
 #include <vector>
 
@@ -21,6 +22,8 @@
 #include "camera_metadata.h"
 #include "system/graphics.h"
 
+#include "jpeg/compressor_jpeg.h"
+
 using namespace libcamera;
 
 namespace {
@@ -80,6 +83,40 @@ const std::map<int, const Camera3Format> camera3FormatsMap = {
 
 LOG_DECLARE_CATEGORY(HAL);
 
+class MappedCamera3Buffer : public MappedBuffer
+{
+public:
+	MappedCamera3Buffer(const buffer_handle_t camera3buffer, int flags)
+	{
+		maps_.reserve(camera3buffer->numFds);
+		error_ = 0;
+
+		for (int i = 0; i < camera3buffer->numFds; i++) {
+			if (camera3buffer->data[i] == -1)
+				continue;
+
+			off_t length = lseek(camera3buffer->data[i], 0, SEEK_END);
+			if (length < 0) {
+				error_ = errno;
+				LOG(HAL, Error) << "Failed to query plane length";
+				break;
+			}
+
+			void *address = mmap(nullptr, length, flags, MAP_SHARED,
+					     camera3buffer->data[i], 0);
+			if (address == MAP_FAILED) {
+				error_ = errno;
+				LOG(HAL, Error) << "Failed to mmap plane";
+				break;
+			}
+
+			maps_.emplace_back(static_cast<uint8_t *>(address), static_cast<size_t>(length));
+		}
+
+		valid_ = error_ == 0;
+	}
+};
+
 /*
  * \struct Camera3RequestDescriptor
  *
@@ -368,9 +405,9 @@ std::tuple<uint32_t, uint32_t> CameraDevice::calculateStaticMetadataSize()
 {
 	/*
 	 * \todo Keep this in sync with the actual number of entries.
-	 * Currently: 50 entries, 647 bytes of static metadata
+	 * Currently: 51 entries, 651 bytes of static metadata
 	 */
-	uint32_t numEntries = 50;
+	uint32_t numEntries = 51;
 	uint32_t byteSize = 651;
 
 	/*
@@ -527,6 +564,9 @@ const camera_metadata_t *CameraDevice::getStaticMetadata()
 				  availableThumbnailSizes.data(),
 				  availableThumbnailSizes.size());
 
+	int32_t jpegMaxSize = 13 << 20; /* 13631488 from USB HAL */
+	staticMetadata_->addEntry(ANDROID_JPEG_MAX_SIZE, &jpegMaxSize, 1);
+
 	/* Sensor static metadata. */
 	int32_t pixelArraySize[] = {
 		2592, 1944,
@@ -729,6 +769,7 @@ const camera_metadata_t *CameraDevice::getStaticMetadata()
 		ANDROID_CONTROL_AWB_LOCK_AVAILABLE,
 		ANDROID_CONTROL_AVAILABLE_MODES,
 		ANDROID_JPEG_AVAILABLE_THUMBNAIL_SIZES,
+		ANDROID_JPEG_MAX_SIZE,
 		ANDROID_SENSOR_INFO_PIXEL_ARRAY_SIZE,
 		ANDROID_SENSOR_INFO_ACTIVE_ARRAY_SIZE,
 		ANDROID_SENSOR_INFO_SENSITIVITY_RANGE,
@@ -795,6 +836,9 @@ const camera_metadata_t *CameraDevice::getStaticMetadata()
 		ANDROID_SENSOR_EXPOSURE_TIME,
 		ANDROID_STATISTICS_LENS_SHADING_MAP_MODE,
 		ANDROID_STATISTICS_SCENE_FLICKER,
+		ANDROID_JPEG_SIZE,
+		ANDROID_JPEG_QUALITY,
+		ANDROID_JPEG_ORIENTATION,
 	};
 	staticMetadata_->addEntry(ANDROID_REQUEST_AVAILABLE_RESULT_KEYS,
 				  availableResultKeys.data(),
@@ -956,6 +1000,7 @@ int CameraDevice::configureStreams(camera3_stream_configuration_t *stream_list)
 	 */
 	unsigned int streamIndex = 0;
 
+	/* First handle all non-MJPEG streams */
 	for (unsigned int i = 0; i < stream_list->num_streams; ++i) {
 		camera3_stream_t *stream = stream_list->streams[i];
 
@@ -971,6 +1016,18 @@ int CameraDevice::configureStreams(camera3_stream_configuration_t *stream_list)
 		if (!format.isValid())
 			return -EINVAL;
 
+		stream->priv = static_cast<void *>(&streams_[i]);
+		streams_[i].format = format;
+		streams_[i].size = Size(stream->width, stream->height);
+
+		/* Defer handling of MJPEG streams until all others are known. */
+		if (format == formats::MJPEG) {
+			LOG(HAL, Info) << "Handling MJPEG stream";
+
+			streams_[i].index = -1;
+			continue;
+		}
+
 		StreamConfiguration streamConfiguration;
 
 		streamConfiguration.size.width = stream->width;
@@ -980,7 +1037,61 @@ int CameraDevice::configureStreams(camera3_stream_configuration_t *stream_list)
 		config_->addConfiguration(streamConfiguration);
 
 		streams_[i].index = streamIndex++;
-		stream->priv = static_cast<void *>(&streams_[i]);
+	}
+
+	/* Now handle MJPEG streams, adding a new stream if required. */
+	for (unsigned int i = 0; i < stream_list->num_streams; ++i) {
+		camera3_stream_t *stream = stream_list->streams[i];
+		CameraStream *cameraStream = &streams_[i];
+
+		/* Only process MJPEG streams */
+		if (cameraStream->format != formats::MJPEG)
+			continue;
+
+		bool match = false;
+
+		/* Search for a compatible stream */
+		for (unsigned int j = 0; j < config_->size(); j++) {
+			StreamConfiguration &cfg = config_->at(j);
+
+			/*
+			 * The PixelFormat must also be compatible with the
+			 * encoder.
+			 */
+			if (cfg.size == cameraStream->size) {
+				LOG(HAL, Info)
+					<< "Stream " << i
+					<< " using libcamera stream "
+					<< j;
+
+				match = true;
+				cameraStream->index = j;
+			}
+		}
+
+		/*
+		 * Without a compatible match for JPEG encoding we must
+		 * introduce a new stream to satisfy the request requirements.
+		 */
+		if (!match) {
+			StreamConfiguration streamConfiguration;
+
+			/*
+			 * \todo: The pixelFormat should be a 'best-fit' choice
+			 * and may require a validation cycle. This is not yet
+			 * handled, and should be considered as part of any
+			 * stream configuration reworks.
+			 */
+			streamConfiguration.size.width = stream->width;
+			streamConfiguration.size.height = stream->height;
+			streamConfiguration.pixelFormat = formats::NV12;
+
+			LOG(HAL, Info) << "Adding " << streamConfiguration.toString()
+				       << " for MJPEG support";
+
+			config_->addConfiguration(streamConfiguration);
+			streams_[i].index = streamIndex++;
+		}
 	}
 
 	switch (config_->validate()) {
@@ -1007,6 +1118,18 @@ int CameraDevice::configureStreams(camera3_stream_configuration_t *stream_list)
 
 		/* Use the bufferCount confirmed by the validation process. */
 		stream->max_buffers = cfg.bufferCount;
+
+		/*
+		 * Construct a software compressor for MJPEG streams from the
+		 * chosen libcamera source stream.
+		 */
+		if (cameraStream->format == formats::MJPEG) {
+			cameraStream->jpeg = new CompressorJPEG();
+			cameraStream->jpeg->configure(cfg);
+		} else {
+			/* Either construct this correctly, or use a better interface */
+			cameraStream->jpeg = nullptr;
+		}
 	}
 
 	/*
@@ -1101,6 +1224,10 @@ int CameraDevice::processCaptureRequest(camera3_capture_request_t *camera3Reques
 		descriptor->buffers[i].stream = camera3Buffers[i].stream;
 		descriptor->buffers[i].buffer = camera3Buffers[i].buffer;
 
+		/* Software streams are handled after hardware streams complete. */
+		if (cameraStream->format == formats::MJPEG)
+			continue;
+
 		/*
 		 * Create a libcamera buffer using the dmabuf descriptors of
 		 * the camera3Buffer for each stream. The FrameBuffer is
@@ -1157,9 +1284,72 @@ void CameraDevice::requestComplete(Request *request)
 	resultMetadata = getResultMetadata(descriptor->frameNumber,
 					   buffer->metadata().timestamp);
 
-	/* Prepare to call back the Android camera stack. */
+	/* Handle any JPEG compression */
+	for (unsigned int i = 0; i < descriptor->numBuffers; ++i) {
+		CameraStream *cameraStream =
+			static_cast<CameraStream *>(descriptor->buffers[i].stream->priv);
+		Compressor *compressor = cameraStream->jpeg;
 
+		/* Only handle streams with compression enabled. */
+		if (!compressor)
+			continue;
 
+		StreamConfiguration *streamConfiguration = &config_->at(cameraStream->index);
+		Stream *stream = streamConfiguration->stream();
+		FrameBuffer *buffer = request->findBuffer(stream);
+		if (!buffer) {
+			LOG(HAL, Error) << "Failed to find a source stream buffer";
+			continue;
+		}
+
+		MappedCamera3Buffer mapped(*descriptor->buffers[i].buffer, PROT_READ | PROT_WRITE);
+		if (!mapped.isValid()) {
+			LOG(HAL, Error) << "Failed to mmap android blob buffer";
+			continue;
+		}
+
+		CompressedImage output;
+		output.data = static_cast<unsigned char *>(mapped.maps()[0].data());
+		output.length = mapped.maps()[0].size();
+
+		int ret = compressor->compress(buffer, &output);
+		if (ret) {
+			LOG(HAL, Error) << "Failed to compress stream image";
+			status = CAMERA3_BUFFER_STATUS_ERROR;
+		}
+
+		/* Fill in the JPEG blob header. */
+		{
+			/* The mapped size of the buffer is being returned as substantially larger
+			 * than the requested JPEG_MAX_SIZE (re-defined here).
+			 * Utilise this static size as a workaround to ensure the correct offset
+			 * of the blob is determined.
+			 *
+			 * \todo Investigate and fix the root cause of this.
+			 */
+			int32_t max_size = { 13 << 20 };
+			uint8_t *resultPtr = static_cast<uint8_t *>(mapped.maps()[0].data()) +
+					     max_size - sizeof(struct camera3_jpeg_blob);
+			auto *blob = reinterpret_cast<struct camera3_jpeg_blob *>(resultPtr);
+
+			blob->jpeg_blob_id = CAMERA3_JPEG_BLOB_ID;
+			blob->jpeg_size = output.length;
+		}
+
+		/* Update the JPEG result Metadata. */
+		resultMetadata->addEntry(ANDROID_JPEG_SIZE,
+					 &output.length, 1);
+
+		const uint32_t jpeg_quality = 95;
+		resultMetadata->addEntry(ANDROID_JPEG_QUALITY,
+					 &jpeg_quality, 1);
+
+		const uint32_t jpeg_orientation = 0;
+		resultMetadata->addEntry(ANDROID_JPEG_ORIENTATION,
+					 &jpeg_orientation, 1);
+	}
+
+	/* Prepare to call back the Android camera stack. */
 	camera3_capture_result_t captureResult = {};
 	captureResult.frame_number = descriptor->frameNumber;
 	captureResult.num_output_buffers = descriptor->numBuffers;
@@ -1240,10 +1430,10 @@ std::unique_ptr<CameraMetadata> CameraDevice::getResultMetadata(int frame_number
 {
 	/*
 	 * \todo Keep this in sync with the actual number of entries.
-	 * Currently: 12 entries, 36 bytes
+	 * Currently: 17 entries, 58 bytes
 	 */
 	std::unique_ptr<CameraMetadata> resultMetadata =
-		std::make_unique<CameraMetadata>(15, 50);
+		std::make_unique<CameraMetadata>(17, 58);
 	if (!resultMetadata->isValid()) {
 		LOG(HAL, Error) << "Failed to allocate static metadata";
 		return nullptr;
diff --git a/src/android/camera_device.h b/src/android/camera_device.h
index 00472c219388..c9ece426a00e 100644
--- a/src/android/camera_device.h
+++ b/src/android/camera_device.h
@@ -23,6 +23,8 @@
 #include "libcamera/internal/log.h"
 #include "libcamera/internal/message.h"
 
+#include "jpeg/compressor_jpeg.h"
+
 class CameraMetadata;
 
 struct CameraStream {
@@ -32,6 +34,12 @@ struct CameraStream {
 	 * one or more streams to the Android framework.
 	 */
 	unsigned int index;
+
+	libcamera::PixelFormat format;
+	libcamera::Size size;
+
+	/* Make sure this gets destructed correctly */
+	CompressorJPEG *jpeg;
 };
 
 class CameraDevice : protected libcamera::Loggable
-- 
2.25.1



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