/** * @file * @brief Header file for WriterBase class * @author Jonathan Thomas * * @ref License */ /* LICENSE * * Copyright (c) 2008-2019 OpenShot Studios, LLC * . This file is part of * OpenShot Library (libopenshot), an open-source project dedicated to * delivering high quality video editing and animation solutions to the * world. For more information visit . * * OpenShot Library (libopenshot) is free software: you can redistribute it * and/or modify it under the terms of the GNU Lesser General Public License * as published by the Free Software Foundation, either version 3 of the * License, or (at your option) any later version. * * OpenShot Library (libopenshot) is distributed in the hope that it will be * useful, but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public License * along with OpenShot Library. If not, see . */ #ifndef OPENSHOT_WRITER_BASE_H #define OPENSHOT_WRITER_BASE_H #include #include #include "ChannelLayouts.h" #include "Fraction.h" #include "Frame.h" #include "ReaderBase.h" #include "ZmqLogger.h" namespace openshot { /** * @brief This struct contains info about encoding a media file, such as height, width, frames per second, etc... * * Each derived class of WriterBase is responsible for updating this struct to reflect accurate information * about the streams. */ struct WriterInfo { bool has_video; ///< Determines if this file has a video stream bool has_audio; ///< Determines if this file has an audio stream bool has_single_image; ///< Determines if this file only contains a single image float duration; ///< Length of time (in seconds) int64_t file_size; ///< Size of file (in bytes) int height; ///< The height of the video (in pixels) int width; ///< The width of the video (in pixels) int pixel_format; ///< The pixel format (i.e. YUV420P, RGB24, etc...) openshot::Fraction fps; ///< Frames per second, as a fraction (i.e. 24/1 = 24 fps) int video_bit_rate; ///< The bit rate of the video stream (in bytes) openshot::Fraction pixel_ratio; ///< The pixel ratio of the video stream as a fraction (i.e. some pixels are not square) openshot::Fraction display_ratio; ///< The ratio of width to height of the video stream (i.e. 640x480 has a ratio of 4/3) std::string vcodec; ///< The name of the video codec used to encode / decode the video stream int64_t video_length; ///< The number of frames in the video stream int video_stream_index; ///< The index of the video stream openshot::Fraction video_timebase; ///< The video timebase determines how long each frame stays on the screen bool interlaced_frame; ///< Are the contents of this frame interlaced bool top_field_first; ///< Which interlaced field should be displayed first std::string acodec; ///< The name of the audio codec used to encode / decode the video stream int audio_bit_rate; ///< The bit rate of the audio stream (in bytes) int sample_rate; ///< The number of audio samples per second (44100 is a common sample rate) int channels; ///< The number of audio channels used in the audio stream openshot::ChannelLayout channel_layout; ///< The channel layout (mono, stereo, 5 point surround, etc...) int audio_stream_index; ///< The index of the audio stream openshot::Fraction audio_timebase; ///< The audio timebase determines how long each audio packet should be played std::map metadata; ///< An optional map/dictionary of video & audio metadata }; /** * @brief This abstract class is the base class, used by writers. Writers are types of classes that encode * video, audio, and image files. * * The only requirements for a 'writer', are to derive from this base class, and implement the * WriteFrame method. */ class WriterBase { public: /// Constructor for WriterBase class, many things are initialized here WriterBase(); /// Information about the current media file WriterInfo info; /// @brief This method copy's the info struct of a reader, and sets the writer with the same info /// @param reader The source reader to copy void CopyReaderInfo(openshot::ReaderBase* reader); /// Determine if writer is open or closed virtual bool IsOpen() = 0; /// This method is required for all derived classes of WriterBase. Write a Frame to the video file. virtual void WriteFrame(std::shared_ptr frame) = 0; /// This method is required for all derived classes of WriterBase. Write a block of frames from a reader. virtual void WriteFrame(openshot::ReaderBase* reader, int64_t start, int64_t length) = 0; /// Get and Set JSON methods std::string Json() const; ///< Generate JSON string of this object Json::Value JsonValue() const; ///< Generate Json::Value for this object void SetJson(const std::string value); ///< Load JSON string into this object void SetJsonValue(const Json::Value root); ///< Load Json::Value into this object /// Display file information in the standard output stream (stdout) void DisplayInfo(); /// Open the writer (and start initializing streams) virtual void Open() = 0; virtual ~WriterBase() = default; }; } #endif