#ifndef OPENSHOT_FILE_READER_BASE_H #define OPENSHOT_FILE_READER_BASE_H /** * \file * \brief Header file for FileReaderBase class * \author Copyright (c) 2011 Jonathan Thomas */ #include #include #include "Fraction.h" #include "Frame.h" using namespace std; namespace openshot { /** * \brief This struct contains info about a media file, such as height, width, frames per second, etc... * * Each derived class of FileReaderBase is responsible for updating this struct to reflect accurate information * about the streams. Derived classes of FileReaderBase should call the InitFileInfo() method to initialize the * default values of this struct. */ struct ReaderInfo { bool has_video; ///< Determines if this file has a video stream bool has_audio; ///< Determines if this file has an audio stream float duration; ///< Length of time (in seconds) int file_size; ///< Size of file (in bytes) int height; ///< The height of the video (in pixels) int width; ///< The width of the video (in pixesl) int pixel_format; ///< The pixel format (i.e. YUV420P, RGB24, etc...) 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) Fraction pixel_ratio; ///< The pixel ratio of the video stream as a fraction (i.e. some pixels are not square) Fraction display_ratio; ///< The ratio of width to height of the video stream (i.e. 640x480 has a ratio of 4/3) string vcodec; ///< The name of the video codec used to encode / decode the video stream long int video_length; ///< The number of frames in the video stream int video_stream_index; ///< The index of the video stream 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 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 int audio_stream_index; ///< The index of the audio stream Fraction audio_timebase; ///< The audio timebase determines how long each audio packet should be played }; /** * \brief This abstract class is the base class, used by readers. Readers are types of classes that read * video, audio, and image files, and return openshot::Frame objects. * * The only requirements for a 'reader', are to derive from this base class, implement the * GetFrame method, and call the InitFileInfo() method. */ class FileReaderBase { public: /// Information about the current media file ReaderInfo info; /// This method is required for all derived classes of FileReaderBase, and return the /// openshot::Frame object, which contains the image and audio information for that /// frame of video. /// /// @returns The requested frame of video /// @param[in] number The frame number that is requested. virtual Frame GetFrame(int number) = 0; /// Initialize the values of the ReaderInfo struct. It is important for derived classes to call /// this method, or the ReaderInfo struct values will not be initialized. void InitFileInfo(); /// Display file information in the standard output stream (stdout) void DisplayInfo(); }; } #endif