// Handles writing of video files. class FrameWriter {
public:
virtual ~FrameWriter() {}
// Initializes the file handler, i.e. opens the input and output files etc. // This must be called before reading or writing frames has started. // Returns false if an error has occurred, in addition to printing to stderr.
virtual bool Init() = 0;
// Writes a frame of the configured frame length to the output file. // Returns true if the write was successful, false otherwise.
virtual bool WriteFrame(const uint8_t* frame_buffer) = 0;
// Closes the output file if open. Essentially makes this class impossible // to use anymore. Will also be invoked by the destructor.
virtual void Close() = 0;
// Frame length in bytes of a single frame image.
virtual size_t FrameLength() = 0;
};
// Writes raw I420 frames in sequence. class YuvFrameWriterImpl : public FrameWriter {
public: // Creates a file handler. The input file is assumed to exist and be readable // and the output file must be writable. // Parameters: // output_filename The file to write. Will be overwritten if already // existing. // width, height Size of each frame to read.
YuvFrameWriterImpl(std::string output_filename, int width, int height);
~YuvFrameWriterImpl() override; bool Init() override; bool WriteFrame(const uint8_t* frame_buffer) override; void Close() override;
size_t FrameLength() override;
// Writes raw I420 frames in sequence, but with Y4M file and frame headers for // more convenient playback in external media players. class Y4mFrameWriterImpl : public YuvFrameWriterImpl {
public:
Y4mFrameWriterImpl(std::string output_filename, int width, int height, int frame_rate);
~Y4mFrameWriterImpl() override; bool Init() override; bool WriteFrame(const uint8_t* frame_buffer) override;
private: constint frame_rate_;
};
// LibJpeg is not available on iOS. This class will do nothing on iOS. class JpegFrameWriter {
public:
JpegFrameWriter(const std::string& output_filename); // Quality can be from 0 (worst) to 100 (best). Best quality is still lossy. // WriteFrame can be called only once. Subsequent calls will fail. bool WriteFrame(const VideoFrame& input_frame, int quality);
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