org.openimaj.video.xuggle

Class XuggleVideo

java.lang.Object

org.openimaj.video.Video<MBFImage>

org.openimaj.video.xuggle.XuggleVideo

All Implemented Interfaces:

Closeable, AutoCloseable, Iterable<MBFImage>

public class XuggleVideo
extends Video<MBFImage>

Wraps a Xuggle video reader into the OpenIMAJ Video interface.

Some Notes:

The hasNextFrame() method must attempt to read the next packet in the stream to determine if there is a next frame. That means that it incurs a time penalty. It also means there's various logic in that method and the getNextFrame() method to avoid reading frames that have already been read. It also means that, to avoid getCurrentFrame() incorrectly returning a new frame after hasNextFrame() has been called, the class may be holding two frames (the current frame and the next frame) after hasNextFrame() has been called.

The constructors have signatures that allow the passing of a boolean that determines whether the video is looped or not. This has a different effect than looping using the VideoDisplay. When the video is set to loop it will loop indefinitely and the timestamp of frames will be consecutive. That is, when the video loops the timestamps will continue to increase. This is in contrast to setting the VideoDisplay end action (using VideoDisplay.setEndAction(org.openimaj.video.VideoDisplay.EndAction) where the looping will reset all timestamps when the video loops.

Author:

David Dupplaw (dpd@ecs.soton.ac.uk), Jonathon Hare (jsh2@ecs.soton.ac.uk), Sina Samangooei (ss@ecs.soton.ac.uk)

Created:

1 Jun 2011

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
protected class	XuggleVideo.FrameGetter This implements the Xuggle MediaTool listener that will be called every time a video picture has been decoded from the stream.
protected static class	XuggleVideo.MBFImageConverter Converter for converting IVideoPictures directly to MBFImages.
protected static class	XuggleVideo.MBFImageWrapper Wrapper that created an MBFImage from a BufferedImage.

Field Summary

Fields

Modifier and Type	Field and Description
boolean	nextFrameIsKeyFrame Whether the next frame is a key frame or not
long	nextFrameTimestamp The timestamp of the next frame

Fields inherited from class org.openimaj.video.Video

currentFrame

Constructor Summary

Constructors

Constructor and Description
XuggleVideo(DataInput input) Default constructor that takes a data input.
XuggleVideo(File videoFile) Default constructor that takes the video file to read.
XuggleVideo(File videoFile, boolean loop) Default constructor that takes the video file to read.
XuggleVideo(InputStream stream) Default constructor that takes an input stream.
XuggleVideo(String url) Default constructor that takes the location of a video file to read.
XuggleVideo(String url, boolean loop) Default constructor that takes the location of a video file to read.
XuggleVideo(URL url) Default constructor that takes the URL of a video file to read.
XuggleVideo(URL url, boolean loop) Default constructor that takes the location of a video file to read.

Method Summary

Modifier and Type	Method and Description
void	close() Close the video object
long	countFrames() Return the number of frames in the whole video.
MBFImage	getCurrentFrame() Get the current frame
int	getCurrentFrameIndex() Get the index of the current frame
VideoTimecode	getCurrentTimecode() Returns a video timecode for the current frame.
long	getDuration() Returns the duration of the video in seconds.
double	getFPS() Get the frame rate
int	getHeight() Get the height of the video frame.
MBFImage	getNextFrame() Get the next frame.
long	getTimeStamp() Get the timestamp of the current frame in milliseconds
int	getWidth() Get the width of the video frame
boolean	hasNextFrame() Returns whether this video has another frame to provide.
void	reset() Reset the video - putting the frame counter back to the start.
void	seek(double timestamp) Seek the video to a given timestamp in SECONDS.
void	seekPrecise(double timestamp) Implements a precise seeking mechanism based on the Xuggle seek method and the naive seek method which simply reads frames.
void	seekToBeginning() This is a convenience method that will seek the stream to be the beginning.
void	setCurrentFrameIndex(long newFrame) Set the current frame index (i.e.

Methods inherited from class org.openimaj.video.Video

iterator

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface java.lang.Iterable

forEach, spliterator

Field Detail

nextFrameTimestamp

public long nextFrameTimestamp

The timestamp of the next frame

nextFrameIsKeyFrame

public boolean nextFrameIsKeyFrame

Whether the next frame is a key frame or not

Constructor Detail

XuggleVideo

public XuggleVideo(File videoFile)

Default constructor that takes the video file to read.

Parameters:

videoFile - The video file to read.

XuggleVideo

public XuggleVideo(File videoFile,
                   boolean loop)

Default constructor that takes the video file to read.

Parameters:

videoFile - The video file to read.

loop - should the video loop

XuggleVideo

public XuggleVideo(String url)

Default constructor that takes the location of a video file to read. This can either be a filename or a URL.

Parameters:

url - The URL of the file to read

XuggleVideo

public XuggleVideo(URL url)

Default constructor that takes the URL of a video file to read.

Parameters:

url - The URL of the file to read

XuggleVideo

public XuggleVideo(URL url,
                   boolean loop)

Default constructor that takes the location of a video file to read. This can either be a filename or a URL. The second parameter determines whether the video will loop indefinitely. If so, getNextFrame() will never return null; otherwise this method will return null at the end of the video.

Parameters:

url - The URL of the file to read

loop - Whether to loop the video indefinitely

XuggleVideo

public XuggleVideo(String url,
                   boolean loop)

Default constructor that takes the location of a video file to read. This can either be a filename or a URL. The second parameter determines whether the video will loop indefinitely. If so, getNextFrame() will never return null; otherwise this method will return null at the end of the video.

Parameters:

url - The URL of the file to read

loop - Whether to loop the video indefinitely

XuggleVideo

public XuggleVideo(InputStream stream)

Default constructor that takes an input stream. Note that only "streamable" video codecs can be used in this way.

Parameters:

stream - The video data stream

XuggleVideo

public XuggleVideo(DataInput input)

Default constructor that takes a data input. Note that only "streamable" video codecs can be used in this way.

Parameters:

input - The video data

Method Detail

countFrames

public long countFrames()

Return the number of frames in the whole video. If the video is a live stream, then this method should return -1.

Specified by:

countFrames in class Video<MBFImage>

Returns:

the number of frames in the whole video or -1 if unknown

See Also:

Video.countFrames()

getNextFrame

public MBFImage getNextFrame()

Get the next frame. Increments the frame counter by 1.

Specified by:

getNextFrame in class Video<MBFImage>

Returns:

the next frame

See Also:

Video.getNextFrame()

getCurrentTimecode

public VideoTimecode getCurrentTimecode()

Returns a video timecode for the current frame.

Returns:

A video timecode for the current frame.

getCurrentFrame

public MBFImage getCurrentFrame()

Get the current frame

Specified by:

getCurrentFrame in class Video<MBFImage>

Returns:

the current frame

See Also:

Video.getCurrentFrame()

getWidth

public int getWidth()

Get the width of the video frame

Specified by:

getWidth in class Video<MBFImage>

Returns:

the width of the video frame.

See Also:

Video.getWidth()

getHeight

public int getHeight()

Get the height of the video frame.

Specified by:

getHeight in class Video<MBFImage>

Returns:

the height of the video frame.

See Also:

Video.getHeight()

hasNextFrame

public boolean hasNextFrame()

Returns whether this video has another frame to provide.

Specified by:

hasNextFrame in class Video<MBFImage>

Returns:

Whether the video has another frame available

See Also:

Video.hasNextFrame()

reset

public void reset()

Reset the video - putting the frame counter back to the start.

Note: if you created the video from a DataInput or InputStream, there is no way that it can be reset.

Specified by:

reset in class Video<MBFImage>

See Also:

Video.reset()

seekToBeginning

public void seekToBeginning()

This is a convenience method that will seek the stream to be the beginning. As the seek method seems a bit flakey in some codec containers in Xuggle, we'll try and use a few different methods to get us back to the beginning. That means that this method may be slower than seek(0) if it needs to try multiple methods.

Note: if you created the video from a DataInput or InputStream, there is no way that it can be reset.

getTimeStamp

public long getTimeStamp()

Get the timestamp of the current frame in milliseconds

Specified by:

getTimeStamp in class Video<MBFImage>

Returns:

the time stamp in milliseconds

See Also:

Video.getTimeStamp()

getFPS

public double getFPS()

Get the frame rate

Specified by:

getFPS in class Video<MBFImage>

Returns:

the frame rate

See Also:

Video.getFPS()

getCurrentFrameIndex

public int getCurrentFrameIndex()

Get the index of the current frame

Overrides:

getCurrentFrameIndex in class Video<MBFImage>

Returns:

the current frame index

See Also:

Video.getCurrentFrameIndex()

setCurrentFrameIndex

public void setCurrentFrameIndex(long newFrame)

Set the current frame index (i.e. skips to a certain frame). If your video subclass can implement this in a cleverer way, then override this method, otherwise this method will simply grab frames until it gets to the given frame index. This method is naive and may take some time as each frame will be decoded by the video decoder.

Overrides:

setCurrentFrameIndex in class Video<MBFImage>

Parameters:

newFrame - the new index

See Also:

Video.setCurrentFrameIndex(long)

seekPrecise

public void seekPrecise(double timestamp)

Implements a precise seeking mechanism based on the Xuggle seek method and the naive seek method which simply reads frames.

Note: if you created the video from a DataInput or InputStream, you can only seek forwards.

Parameters:

timestamp - The timestamp to get, in seconds.

seek

public void seek(double timestamp)

Seek the video to a given timestamp in SECONDS. Many videos (including cameras etc.) will have no ability to seek so by default this function does nothing.

Note: if you created the video from a DataInput or InputStream, you can only seek forwards.

Overrides:

seek in class Video<MBFImage>

See Also:

Video.seek(double)

getDuration

public long getDuration()

Returns the duration of the video in seconds.

Returns:

The duration of the video in seconds.

close

public void close()

Close the video object

Specified by:

close in interface Closeable

Specified by:

close in interface AutoCloseable

Overrides:

close in class Video<MBFImage>

See Also:

Video.close()