org.bytedeco.javacv

Class OpenCVFrameGrabber

java.lang.Object

org.bytedeco.javacv.FrameGrabber

org.bytedeco.javacv.OpenCVFrameGrabber

All Implemented Interfaces:

Closeable, AutoCloseable

public class OpenCVFrameGrabber
extends FrameGrabber

Author:

Samuel Audet, Lloyd (github.com/lloydmeta)

Nested Class Summary

Nested classes/interfaces inherited from class org.bytedeco.javacv.FrameGrabber

FrameGrabber.Array, FrameGrabber.Exception, FrameGrabber.ImageMode, FrameGrabber.PropertyEditor, FrameGrabber.SampleMode

Field Summary

Fields inherited from class org.bytedeco.javacv.FrameGrabber

aspectRatio, audioBitrate, audioChannels, audioCodec, audioCodecName, audioDisposition, audioMetadata, audioOptions, audioSideData, audioStream, bpp, charset, deinterlace, format, frameNumber, frameRate, gamma, imageHeight, imageMode, imageScalingFlags, imageWidth, list, maxDelay, metadata, numBuffers, options, pixelFormat, sampleFormat, sampleMode, sampleRate, SENSOR_PATTERN_BGGR, SENSOR_PATTERN_GBRG, SENSOR_PATTERN_GRBG, SENSOR_PATTERN_RGGB, sensorPattern, startTime, timeout, timestamp, triggerMode, videoBitrate, videoCodec, videoCodecName, videoDisposition, videoMetadata, videoOptions, videoSideData, videoStream

Constructor Summary

Constructors

Constructor and Description
OpenCVFrameGrabber(File file)
OpenCVFrameGrabber(File file, int apiPreference)
OpenCVFrameGrabber(int deviceNumber)
OpenCVFrameGrabber(String filename)
OpenCVFrameGrabber(String filename, int apiPreference)

Method Summary

Modifier and Type	Method and Description
static OpenCVFrameGrabber	createDefault(File deviceFile)
static OpenCVFrameGrabber	createDefault(int deviceNumber)
static OpenCVFrameGrabber	createDefault(String devicePath)
protected void	finalize()
static String[]	getDeviceDescriptions()
String	getFormat()
int	getFrameNumber()
double	getFrameRate()
double	getGamma()
int	getImageHeight()
int	getImageWidth()
int	getLengthInFrames()
long	getLengthInTime()
double	getOption(int propId)
int	getPixelFormat()
long	getTimestamp()
Frame	grab() Each call to grab stores the new image in the memory address for the previously returned frame.
void	release()
void	setFrameNumber(int frameNumber)
void	setImageMode(FrameGrabber.ImageMode imageMode)
void	setOption(int propId, double value)
void	setTimestamp(long timestamp)
void	start()
void	stop()
void	trigger()
static void	tryLoad()

Methods inherited from class org.bytedeco.javacv.FrameGrabber

close, create, create, create, create, createArray, delayedGrab, flush, get, getAspectRatio, getAudioBitrate, getAudioChannels, getAudioCodec, getAudioCodecName, getAudioDisposition, getAudioMetadata, getAudioMetadata, getAudioOption, getAudioOptions, getAudioSideData, getAudioSideData, getAudioStream, getBitsPerPixel, getCharset, getDefault, getDelayedFrame, getDelayedTime, getImageMode, getImageScalingFlags, getMaxDelay, getMetadata, getMetadata, getNumBuffers, getOption, getOptions, getSampleFormat, getSampleMode, getSampleRate, getSensorPattern, getTimeout, getVideoBitrate, getVideoCodec, getVideoCodecName, getVideoDisposition, getVideoMetadata, getVideoMetadata, getVideoOption, getVideoOptions, getVideoSideData, getVideoSideData, getVideoStream, grabAtFrameRate, grabFrame, init, isDeinterlace, isTriggerMode, resetStartTime, restart, setAspectRatio, setAudioBitrate, setAudioChannels, setAudioCodec, setAudioCodecName, setAudioDisposition, setAudioMetadata, setAudioMetadata, setAudioOption, setAudioOptions, setAudioSideData, setAudioSideData, setAudioStream, setBitsPerPixel, setCharset, setDeinterlace, setFormat, setFrameRate, setGamma, setImageHeight, setImageScalingFlags, setImageWidth, setMaxDelay, setMetadata, setMetadata, setNumBuffers, setOption, setOptions, setPixelFormat, setSampleFormat, setSampleMode, setSampleRate, setSensorPattern, setTimeout, setTriggerMode, setVideoBitrate, setVideoCodec, setVideoCodecName, setVideoDisposition, setVideoMetadata, setVideoMetadata, setVideoOption, setVideoOptions, setVideoSideData, setVideoSideData, setVideoStream, waitForTimestamp

Methods inherited from class java.lang.Object

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

Constructor Detail

OpenCVFrameGrabber

public OpenCVFrameGrabber(int deviceNumber)

OpenCVFrameGrabber

public OpenCVFrameGrabber(File file)

OpenCVFrameGrabber

public OpenCVFrameGrabber(File file,
                          int apiPreference)

OpenCVFrameGrabber

public OpenCVFrameGrabber(String filename)

OpenCVFrameGrabber

public OpenCVFrameGrabber(String filename,
                          int apiPreference)

Method Detail

getDeviceDescriptions

public static String[] getDeviceDescriptions()
                                      throws FrameGrabber.Exception

Throws:

FrameGrabber.Exception

createDefault

public static OpenCVFrameGrabber createDefault(File deviceFile)
                                        throws FrameGrabber.Exception

Throws:

FrameGrabber.Exception

createDefault

public static OpenCVFrameGrabber createDefault(String devicePath)
                                        throws FrameGrabber.Exception

Throws:

FrameGrabber.Exception

createDefault

public static OpenCVFrameGrabber createDefault(int deviceNumber)
                                        throws FrameGrabber.Exception

Throws:

FrameGrabber.Exception

tryLoad

public static void tryLoad()
                    throws FrameGrabber.Exception

Throws:

FrameGrabber.Exception

release

public void release()
             throws FrameGrabber.Exception

Specified by:

release in class FrameGrabber

Throws:

FrameGrabber.Exception

finalize

protected void finalize()
                 throws Throwable

Overrides:

finalize in class Object

Throws:

Throwable

getGamma

public double getGamma()

Overrides:

getGamma in class FrameGrabber

getFormat

public String getFormat()

Overrides:

getFormat in class FrameGrabber

getImageWidth

public int getImageWidth()

Overrides:

getImageWidth in class FrameGrabber

getImageHeight

public int getImageHeight()

Overrides:

getImageHeight in class FrameGrabber

getPixelFormat

public int getPixelFormat()

Overrides:

getPixelFormat in class FrameGrabber

getFrameRate

public double getFrameRate()

Overrides:

getFrameRate in class FrameGrabber

setImageMode

public void setImageMode(FrameGrabber.ImageMode imageMode)

Overrides:

setImageMode in class FrameGrabber

getFrameNumber

public int getFrameNumber()

Overrides:

getFrameNumber in class FrameGrabber

setFrameNumber

public void setFrameNumber(int frameNumber)
                    throws FrameGrabber.Exception

Overrides:

setFrameNumber in class FrameGrabber

Throws:

FrameGrabber.Exception

getTimestamp

public long getTimestamp()

Overrides:

getTimestamp in class FrameGrabber

setTimestamp

public void setTimestamp(long timestamp)
                  throws FrameGrabber.Exception

Overrides:

setTimestamp in class FrameGrabber

Throws:

FrameGrabber.Exception

getLengthInFrames

public int getLengthInFrames()

Overrides:

getLengthInFrames in class FrameGrabber

getLengthInTime

public long getLengthInTime()

Overrides:

getLengthInTime in class FrameGrabber

getOption

public double getOption(int propId)

setOption

public void setOption(int propId,
                      double value)

Parameters:

propId - Property ID, look at opencv_videoio for possible values

value -

start

public void start()
           throws FrameGrabber.Exception

Specified by:

start in class FrameGrabber

Throws:

FrameGrabber.Exception

stop

public void stop()
          throws FrameGrabber.Exception

Specified by:

stop in class FrameGrabber

Throws:

FrameGrabber.Exception

trigger

public void trigger()
             throws FrameGrabber.Exception

Specified by:

trigger in class FrameGrabber

Throws:

FrameGrabber.Exception

grab

public Frame grab()
           throws FrameGrabber.Exception

Description copied from class: FrameGrabber

Each call to grab stores the new image in the memory address for the previously returned frame.
IE.
grabber.grab() == grabber.grab()
This means that if you need to cache images returned from grab you should Frame.clone() the returned frame as the next call to grab will overwrite your existing image's memory.
Why?
Using this method instead of allocating a new buffer every time a frame is grabbed improves performance by reducing the frequency of garbage collections. Almost no additional heap space is typically allocated per frame.

Specified by:

grab in class FrameGrabber

Returns:

The frame returned from the grabber

Throws:

FrameGrabber.Exception