android: post_processor: Consolidate contextual information

Save and provide the context for post-processor of a camera stream
via Camera3RequestDescriptor::StreamBuffer. We extend the structure
to include source and destination buffers for the post processor, along
with CameraStream::Type::Internal buffer pointer (if any). In addition
to that, a back pointer to Camera3RequestDescriptor is convenient to
get access to overall descriptor (status, metadata settings etc.).

Also, migrate CameraStream::process() and PostProcessor::process()
signature to use Camera3RequestDescriptor::StreamBuffer only. This
will be helpful when we move to async post-processing in subsequent
commits.

Signed-off-by: Umang Jain <umang.jain@ideasonboard.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Hirokazu Honda <hiroh@chromium.org>

src/android/camera_device.cpp

@@ -953,6 +953,7 @@ int CameraDevice::processCaptureRequest(camera3_capture_request_t *camera3Reques
 			 * once it has been processed.
 			 */
 			frameBuffer = cameraStream->getBuffer();
+			buffer.internalBuffer = frameBuffer;
 			LOG(HAL, Debug) << ss.str() << " (internal)";
 			break;
 		}
@@ -1133,14 +1134,16 @@ void CameraDevice::requestComplete(Request *request)
 			continue;
 		}
 
-		int ret = stream->process(*src, buffer, descriptor);
+		buffer.srcBuffer = src;
+
+		int ret = stream->process(&buffer);
 
 		/*
-		 * Return the FrameBuffer to the CameraStream now that we're
+		 * If the framebuffer is internal to CameraStream return it back
-		 * done processing it.
+		 * now that we're done processing it.
 		 */
-		if (stream->type() == CameraStream::Type::Internal)
+		if (buffer.internalBuffer)
-			stream->putBuffer(src);
+			stream->putBuffer(buffer.internalBuffer);
 
 		if (ret) {
 			buffer.status = Camera3RequestDescriptor::Status::Error;

src/android/camera_request.cpp

@@ -9,6 +9,8 @@
 
 #include <libcamera/base/span.h>
 
+#include "camera_buffer.h"
+
 using namespace libcamera;
 
 /*
@@ -36,7 +38,8 @@ Camera3RequestDescriptor::Camera3RequestDescriptor(
 			static_cast<CameraStream *>(buffer.stream->priv);
 
 		buffers_.push_back({ stream, buffer.buffer, nullptr,
-				     buffer.acquire_fence, Status::Success });
+				     buffer.acquire_fence, Status::Success,
+				     nullptr, nullptr, nullptr, this });
 	}
 
 	/* Clone the controls associated with the camera3 request. */

src/android/camera_request.h

@@ -20,6 +20,7 @@
 #include "camera_metadata.h"
 #include "camera_worker.h"
 
+class CameraBuffer;
 class CameraStream;
 
 class Camera3RequestDescriptor
@@ -36,6 +37,10 @@ public:
 		std::unique_ptr<libcamera::FrameBuffer> frameBuffer;
 		int fence;
 		Status status;
+		libcamera::FrameBuffer *internalBuffer;
+		const libcamera::FrameBuffer *srcBuffer;
+		std::unique_ptr<CameraBuffer> dstBuffer;
+		Camera3RequestDescriptor *request;
 	};
 
 	Camera3RequestDescriptor(libcamera::Camera *camera,

src/android/camera_stream.cpp

@@ -146,23 +146,21 @@ int CameraStream::waitFence(int fence)
 	return -errno;
 }
 
-int CameraStream::process(const FrameBuffer &source,
+int CameraStream::process(Camera3RequestDescriptor::StreamBuffer *streamBuffer)
-			  Camera3RequestDescriptor::StreamBuffer &dest,
-			  Camera3RequestDescriptor *request)
 {
 	ASSERT(type_ != Type::Direct);
 
 	/* Handle waiting on fences on the destination buffer. */
-	if (dest.fence != -1) {
+	if (streamBuffer->fence != -1) {
-		int ret = waitFence(dest.fence);
+		int ret = waitFence(streamBuffer->fence);
 		if (ret < 0) {
 			LOG(HAL, Error) << "Failed waiting for fence: "
-					<< dest.fence << ": " << strerror(-ret);
+					<< streamBuffer->fence << ": " << strerror(-ret);
 			return ret;
 		}
 
-		::close(dest.fence);
+		::close(streamBuffer->fence);
-		dest.fence = -1;
+		streamBuffer->fence = -1;
 	}
 
 	/*
@@ -170,14 +168,15 @@ int CameraStream::process(const FrameBuffer &source,
 	 * separate thread.
 	 */
 	const StreamConfiguration &output = configuration();
-	CameraBuffer destBuffer(*dest.camera3Buffer, output.pixelFormat,
+	streamBuffer->dstBuffer = std::make_unique<CameraBuffer>(
-				output.size, PROT_READ | PROT_WRITE);
+		*streamBuffer->camera3Buffer, output.pixelFormat, output.size,
-	if (!destBuffer.isValid()) {
+		PROT_READ | PROT_WRITE);
+	if (!streamBuffer->dstBuffer->isValid()) {
 		LOG(HAL, Error) << "Failed to create destination buffer";
 		return -EINVAL;
 	}
 
-	return postProcessor_->process(source, &destBuffer, request);
+	return postProcessor_->process(streamBuffer);
 }
 
 FrameBuffer *CameraStream::getBuffer()

src/android/camera_stream.h

@@ -121,9 +121,7 @@ public:
 	libcamera::Stream *stream() const;
 
 	int configure();
-	int process(const libcamera::FrameBuffer &source,
+	int process(Camera3RequestDescriptor::StreamBuffer *streamBuffer);
-		    Camera3RequestDescriptor::StreamBuffer &dest,
-		    Camera3RequestDescriptor *request);
 	libcamera::FrameBuffer *getBuffer();
 	void putBuffer(libcamera::FrameBuffer *buffer);
 

src/android/jpeg/post_processor_jpeg.cpp

@@ -98,15 +98,17 @@ void PostProcessorJpeg::generateThumbnail(const FrameBuffer &source,
 	}
 }
 
-int PostProcessorJpeg::process(const FrameBuffer &source,
+int PostProcessorJpeg::process(Camera3RequestDescriptor::StreamBuffer *streamBuffer)
-			       CameraBuffer *destination,
-			       Camera3RequestDescriptor *request)
 {
 	ASSERT(encoder_);
+
+	const FrameBuffer &source = *streamBuffer->srcBuffer;
+	CameraBuffer *destination = streamBuffer->dstBuffer.get();
+
 	ASSERT(destination->numPlanes() == 1);
 
-	const CameraMetadata &requestMetadata = request->settings_;
+	const CameraMetadata &requestMetadata = streamBuffer->request->settings_;
-	CameraMetadata *resultMetadata = request->resultMetadata_.get();
+	CameraMetadata *resultMetadata = streamBuffer->request->resultMetadata_.get();
 	camera_metadata_ro_entry_t entry;
 	int ret;
 

src/android/jpeg/post_processor_jpeg.h

@@ -22,9 +22,7 @@ public:
 
 	int configure(const libcamera::StreamConfiguration &incfg,
 		      const libcamera::StreamConfiguration &outcfg) override;
-	int process(const libcamera::FrameBuffer &source,
+	int process(Camera3RequestDescriptor::StreamBuffer *streamBuffer) override;
-		    CameraBuffer *destination,
-		    Camera3RequestDescriptor *request) override;
 
 private:
 	void generateThumbnail(const libcamera::FrameBuffer &source,

src/android/post_processor.h

@@ -11,8 +11,7 @@
 #include <libcamera/stream.h>
 
 #include "camera_buffer.h"
-
+#include "camera_request.h"
-class Camera3RequestDescriptor;
 
 class PostProcessor
 {
@@ -21,9 +20,7 @@ public:
 
 	virtual int configure(const libcamera::StreamConfiguration &inCfg,
 			      const libcamera::StreamConfiguration &outCfg) = 0;
-	virtual int process(const libcamera::FrameBuffer &source,
+	virtual int process(Camera3RequestDescriptor::StreamBuffer *streamBuffer) = 0;
-			    CameraBuffer *destination,
-			    Camera3RequestDescriptor *request) = 0;
 };
 
 #endif /* __ANDROID_POST_PROCESSOR_H__ */

src/android/yuv/post_processor_yuv.cpp

@@ -49,10 +49,11 @@ int PostProcessorYuv::configure(const StreamConfiguration &inCfg,
 	return 0;
 }
 
-int PostProcessorYuv::process(const FrameBuffer &source,
+int PostProcessorYuv::process(Camera3RequestDescriptor::StreamBuffer *streamBuffer)
-			      CameraBuffer *destination,
-			      [[maybe_unused]] Camera3RequestDescriptor *request)
 {
+	const FrameBuffer &source = *streamBuffer->srcBuffer;
+	CameraBuffer *destination = streamBuffer->dstBuffer.get();
+
 	if (!isValidBuffers(source, *destination))
 		return -EINVAL;
 

src/android/yuv/post_processor_yuv.h

@@ -18,9 +18,7 @@ public:
 
 	int configure(const libcamera::StreamConfiguration &incfg,
 		      const libcamera::StreamConfiguration &outcfg) override;
-	int process(const libcamera::FrameBuffer &source,
+	int process(Camera3RequestDescriptor::StreamBuffer *streamBuffer) override;
-		    CameraBuffer *destination,
-		    Camera3RequestDescriptor *request) override;
 
 private:
 	bool isValidBuffers(const libcamera::FrameBuffer &source,