The buffered recorder class creates the video file from the images. More...

#include <recorder.h>

Public Member Functions
	DISALLOW_COPY_AND_ASSIGN (Recorder)
	Copy and assign of the class is not allowed.

unsigned int	countBuffered ()
	Counts the currently buffered images. More...

unsigned int	getMissedFrames ()
	Returns the count of the missed frames. More...

unsigned int	getRecordedFrames ()
	Returns the recorded frames. More...

bool	isOpen ()
	Returns the initialization status of the recorder. More...

bool	isTerminated ()
	Retrieves the recorder status. More...

bool	open (const std::string &filename, int fourcc, double fps, cv::Size frameSize, bool isColor=true)
	Opens the video recorder. More...

RecorderStats	push (const cv::Mat &image)
	Pushes the new image to the buffer. More...

bool	repush ()
	Repushes the last image again to the buffer. More...

void	stop ()
	Softly stops the recording. More...

Static Public Member Functions
static void	detach (std::unique_ptr< Recorder > &&ptr)
	Detaches the recorder. More...

Detailed Description

The buffered recorder class creates the video file from the images.

This is basically just a wrapper around cv::VideoWriter so that there is a simple buffer that allows multithreading. The class should only be used for one video file recording and then deleted. Once the recorder is succesfully opened, it cannot be re-opened even after termination.

When the recorder is to be opened, it is provided with all necessary information for the video file creation. The images are added to the buffer with push(). Recorder will write the contents of the buffer to the video file with the initialized parameters, and will continue to do so until it is terminated. Recorder can be stopped with stop() in order to finish writing the buffer contents. This allows it to flush the buffer contents and close the file properly.

Method isTerminated() can be used to check when Recorder has finished flushing the buffer after stop() signal. If Recorder object is destroyed before termination is successful, it will also destroy the rest of the buffer contents, thus leading into lost video frames. The destruction of Recorder should not leave video files corrupted, as it tries to close the files properly.

Author: Petri Partanen

Remarks: All public methods are thread-safe.

Member Function Documentation

unsigned int cavapa_gui::Recorder::countBuffered ( )

Counts the currently buffered images.

Returns: The number of images in the buffer.

static void cavapa_gui::Recorder::detach ( std::unique_ptr< Recorder > && ptr )

inlinestatic

Detaches the recorder.

It adds the recorder to a cleanup list that holds unfinished records, and let's them flush their buffer peacefully. The recorders on this list are destroyed on flushDetached() call, unless they have not yet terminated.

Parameters

ptr	The recorder to be detached.

Remarks: Recorder should be stopped at this point already.

unsigned int cavapa_gui::Recorder::getMissedFrames ( )

Returns the count of the missed frames.

The missed frames tell the amount of the frames that have been lost due to file writing errors. Most likely the file has no longer been open when the frames were supposed to be written.

Returns: The missed frames.

Remarks: Untested. Not sure if OpenCV actually even fails when the file is no longer open.

unsigned int cavapa_gui::Recorder::getRecordedFrames ( )

Returns the recorded frames.

Returns: The succesfully recorded frames.

Remarks: The images currently in the buffer are not counted.

bool cavapa_gui::Recorder::isOpen ( )

inline

Returns the initialization status of the recorder.

Returns: True if the file writer was opened, false otherwise.

Remarks: This does NOT change if the file is closed!

bool cavapa_gui::Recorder::isTerminated ( )

Retrieves the recorder status.

Returns: True if the recorder has finished writing frames and can be killed without destroying any unwritten frames.

bool cavapa_gui::Recorder::open	(	const std::string &	filename,
		int	fourcc,
		double	fps,
		cv::Size	frameSize,
		bool	isColor = `true`
	)

Opens the video recorder.

The parameters are the same as in cv::VideoWriter, and are passed directly to cv::VideoWriter::open.

Parameters

filename	The name of the output video file.
fourcc	The 4-character code of codec.
fps	The framerate of the created video.
frameSize	The size of the video frames.
isColor	If it is not false, the encoder will expect and encode color frames.

Returns: True if the file was opened successfully or false otherwise.

RecorderStats cavapa_gui::Recorder::push ( const cv::Mat & image )

Pushes the new image to the buffer.

Parameters

image The new OpenCV image. All the images buffered must match in size, otherwise the video file gets broken.

Returns: The current statistics of the Recorder.

bool cavapa_gui::Recorder::repush ( )

Repushes the last image again to the buffer.

Returns: True if repushing was done or false otherwise.

Remarks: Does nothing if no image exists.

void cavapa_gui::Recorder::stop ( )

Softly stops the recording.

This allows the recorder to write the rest of the frames to the buffer. Recorder cannot be restarted after this. If the recorder is deleted before the buffer has finished writing, the frames will be lost forever. Use terminated() to see when the buffer has finished flushing.

Remarks: In order to leave Recorder to peacefully write rest of the frames, it should be detached().

The documentation for this class was generated from the following files:

source/recorder.h
source/recorder.cpp

Public Member Functions

Static Public Member Functions

Detailed Description

Member Function Documentation