From f929a2890ccc3d2cf9be0a73fadcc4c9c40ece79 Mon Sep 17 00:00:00 2001 From: Laurent Pinchart Date: Tue, 19 May 2020 01:54:53 +0300 Subject: cam: Add FrameSink base class MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The FrameSink class serves as a base to implement components that consume frames. This allows handling frame sinks in a generic way, independent of their nature. The BufferWrite class will be ported to FrameSink in a second step. Signed-off-by: Laurent Pinchart Reviewed-by: Niklas Söderlund Reviewed-by: Paul Elder Reviewed-by: Kieran Bingham Reviewed-by: Umang Jain --- src/cam/frame_sink.cpp | 67 ++++++++++++++++++++++++++++++++++++++++++++++++++ src/cam/frame_sink.h | 34 +++++++++++++++++++++++++ src/cam/meson.build | 1 + 3 files changed, 102 insertions(+) create mode 100644 src/cam/frame_sink.cpp create mode 100644 src/cam/frame_sink.h (limited to 'src/cam') diff --git a/src/cam/frame_sink.cpp b/src/cam/frame_sink.cpp new file mode 100644 index 00000000..af21d575 --- /dev/null +++ b/src/cam/frame_sink.cpp @@ -0,0 +1,67 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +/* + * Copyright (C) 2021, Ideas on Board Oy + * + * frame_sink.cpp - Base Frame Sink Class + */ + +#include "frame_sink.h" + +/** + * \class FrameSink + * \brief Abstract class to model a consumer of frames + * + * The FrameSink class models the consumer that processes frames after a request + * completes. It receives requests through processRequest(), and processes them + * synchronously or asynchronously. This allows frame sinks to hold onto frames + * for an extended period of time, for instance to display them until a new + * frame arrives. + * + * A frame sink processes whole requests, and is solely responsible for deciding + * how to handle different frame buffers in case multiple streams are captured. + */ + +FrameSink::~FrameSink() +{ +} + +int FrameSink::configure([[maybe_unused]] const libcamera::CameraConfiguration &config) +{ + return 0; +} + +void FrameSink::mapBuffer([[maybe_unused]] libcamera::FrameBuffer *buffer) +{ +} + +int FrameSink::start() +{ + return 0; +} + +int FrameSink::stop() +{ + return 0; +} + +/** + * \fn FrameSink::processRequest() + * \param[in] request The request + * + * This function is called to instruct the sink to process a request. The sink + * may process the request synchronously or queue it for asynchronous + * processing. + * + * When the request is processed synchronously, this function shall return true. + * The \a request shall not be accessed by the FrameSink after the function + * returns. + * + * When the request is processed asynchronously, the FrameSink temporarily takes + * ownership of the \a request. The function shall return false, and the + * FrameSink shall emit the requestProcessed signal when the request processing + * completes. If the stop() function is called before the request processing + * completes, it shall release the request synchronously. + * + * \return True if the request has been processed synchronously, false if + * processing has been queued + */ diff --git a/src/cam/frame_sink.h b/src/cam/frame_sink.h new file mode 100644 index 00000000..76e1fc30 --- /dev/null +++ b/src/cam/frame_sink.h @@ -0,0 +1,34 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +/* + * Copyright (C) 2021, Ideas on Board Oy + * + * frame_sink.h - Base Frame Sink Class + */ +#ifndef __CAM_FRAME_SINK_H__ +#define __CAM_FRAME_SINK_H__ + +#include + +namespace libcamera { +class CameraConfiguration; +class FrameBuffer; +class Request; +} /* namespace libcamera */ + +class FrameSink +{ +public: + virtual ~FrameSink(); + + virtual int configure(const libcamera::CameraConfiguration &config); + + virtual void mapBuffer(libcamera::FrameBuffer *buffer); + + virtual int start(); + virtual int stop(); + + virtual bool processRequest(libcamera::Request *request) = 0; + libcamera::Signal requestProcessed; +}; + +#endif /* __CAM_FRAME_SINK_H__ */ diff --git a/src/cam/meson.build b/src/cam/meson.build index 1e90ee52..649cc990 100644 --- a/src/cam/meson.build +++ b/src/cam/meson.build @@ -13,6 +13,7 @@ cam_sources = files([ 'buffer_writer.cpp', 'camera_session.cpp', 'event_loop.cpp', + 'frame_sink.cpp', 'main.cpp', 'options.cpp', 'stream_options.cpp', -- cgit v1.2.1