package org.opencv.highgui;
import java.util.List;
import java.util.LinkedList;
import org.opencv.core.Mat;
import org.opencv.core.Size;
// C++: class VideoCapture
/**
* <p>Class for video capturing from video files or cameras.
* The class provides C++ API for capturing video from cameras or for reading
* video files. Here is how the class can be used:</p>
*
* <p>#include "opencv2/opencv.hpp" <code></p>
*
* <p>// C++ code:</p>
*
* <p>using namespace cv;</p>
*
* <p>int main(int, char)</p>
*
*
* <p>VideoCapture cap(0); // open the default camera</p>
*
* <p>if(!cap.isOpened()) // check if we succeeded</p>
*
* <p>return -1;</p>
*
* <p>Mat edges;</p>
*
* <p>namedWindow("edges",1);</p>
*
* <p>for(;;)</p>
*
*
* <p>Mat frame;</p>
*
* <p>cap >> frame; // get a new frame from camera</p>
*
* <p>cvtColor(frame, edges, CV_BGR2GRAY);</p>
*
* <p>GaussianBlur(edges, edges, Size(7,7), 1.5, 1.5);</p>
*
* <p>Canny(edges, edges, 0, 30, 3);</p>
*
* <p>imshow("edges", edges);</p>
*
* <p>if(waitKey(30) >= 0) break;</p>
*
*
* <p>// the camera will be deinitialized automatically in VideoCapture destructor</p>
*
* <p>return 0;</p>
*
*
* <p>Note: In C API the black-box structure <code>CvCapture</code> is used instead
* of <code>VideoCapture</code>.
* </code></p>
*
* <p>Note:</p>
* <ul>
* <li> A basic sample on using the VideoCapture interface can be found at
* opencv_source_code/samples/cpp/starter_video.cpp
* <li> Another basic video processing sample can be found at
* opencv_source_code/samples/cpp/video_dmtx.cpp
* <li> (Python) A basic sample on using the VideoCapture interface can be
* found at opencv_source_code/samples/python2/video.py
* <li> (Python) Another basic video processing sample can be found at
* opencv_source_code/samples/python2/video_dmtx.py
* <li> (Python) A multi threaded video processing sample can be found at
* opencv_source_code/samples/python2/video_threaded.py
* </ul>
*
* @see <a href="http://docs.opencv.org/modules/highgui/doc/reading_and_writing_images_and_video.html#videocapture">org.opencv.highgui.VideoCapture</a>
*/
public class VideoCapture {
protected final long nativeObj;
protected VideoCapture(long addr) {
nativeObj = addr;
}
//
// C++: VideoCapture::VideoCapture()
//
/**
* <p>VideoCapture constructors.</p>
*
* <p>Note: In C API, when you finished working with video, release
* <code>CvCapture</code> structure with <code>cvReleaseCapture()</code>, or use
* <code>Ptr<CvCapture></code> that calls <code>cvReleaseCapture()</code>
* automatically in the destructor.</p>
*
* @see <a href="http://docs.opencv.org/modules/highgui/doc/reading_and_writing_images_and_video.html#videocapture-videocapture">org.opencv.highgui.VideoCapture.VideoCapture</a>
*/
public VideoCapture()
{
nativeObj = n_VideoCapture();
return;
}
//
// C++: VideoCapture::VideoCapture(int device)
//
/**
* <p>VideoCapture constructors.</p>
*
* <p>Note: In C API, when you finished working with video, release
* <code>CvCapture</code> structure with <code>cvReleaseCapture()</code>, or use
* <code>Ptr<CvCapture></code> that calls <code>cvReleaseCapture()</code>
* automatically in the destructor.</p>
*
* @param device id of the opened video capturing device (i.e. a camera index).
* If there is a single camera connected, just pass 0.
*
* @see <a href="http://docs.opencv.org/modules/highgui/doc/reading_and_writing_images_and_video.html#videocapture-videocapture">org.opencv.highgui.VideoCapture.VideoCapture</a>
*/
public VideoCapture(int device)
{
nativeObj = n_VideoCapture(device);
return;
}
//
// C++: double VideoCapture::get(int propId)
//
/**
* Returns the specified "VideoCapture" property.
*
* Note: When querying a property that is not supported by the backend used by
* the "VideoCapture" class, value 0 is returned.
*
* @param propId property identifier; it can be one of the following:
* * CV_CAP_PROP_FRAME_WIDTH width of the frames in the video stream.
* * CV_CAP_PROP_FRAME_HEIGHT height of the frames in the video stream.
*
* @see <a href="http://docs.opencv.org/modules/highgui/doc/reading_and_writing_images_and_video.html#videocapture-get">org.opencv.highgui.VideoCapture.get</a>
*/
public double get(int propId)
{
double retVal = n_get(nativeObj, propId);
return retVal;
}
public List<Size> getSupportedPreviewSizes()
{
String[] sizes_str = n_getSupportedPreviewSizes(nativeObj).split(",");
List<Size> sizes = new LinkedList<Size>();
for (String str : sizes_str) {
String[] wh = str.split("x");
sizes.add(new Size(Double.parseDouble(wh[0]), Double.parseDouble(wh[1])));
}
return sizes;
}
//
// C++: bool VideoCapture::grab()
//
/**
* <p>Grabs the next frame from video file or capturing device.</p>
*
* <p>The methods/functions grab the next frame from video file or camera and
* return true (non-zero) in the case of success.</p>
*
* <p>The primary use of the function is in multi-camera environments, especially
* when the cameras do not have hardware synchronization. That is, you call
* <code>VideoCapture.grab()</code> for each camera and after that call the
* slower method <code>VideoCapture.retrieve()</code> to decode and get frame
* from each camera. This way the overhead on demosaicing or motion jpeg
* decompression etc. is eliminated and the retrieved frames from different
* cameras will be closer in time.</p>
*
* <p>Also, when a connected camera is multi-head (for example, a stereo camera or
* a Kinect device), the correct way of retrieving data from it is to call
* "VideoCapture.grab" first and then call "VideoCapture.retrieve" one or more
* times with different values of the <code>channel</code> parameter. See
* https://github.com/Itseez/opencv/tree/master/samples/cpp/openni_capture.cpp</p>
*
* @see <a href="http://docs.opencv.org/modules/highgui/doc/reading_and_writing_images_and_video.html#videocapture-grab">org.opencv.highgui.VideoCapture.grab</a>
*/
public boolean grab()
{
boolean retVal = n_grab(nativeObj);
return retVal;
}
//
// C++: bool VideoCapture::isOpened()
//
/**
* <p>Returns true if video capturing has been initialized already.</p>
*
* <p>If the previous call to <code>VideoCapture</code> constructor or
* <code>VideoCapture.open</code> succeeded, the method returns true.</p>
*
* @see <a href="http://docs.opencv.org/modules/highgui/doc/reading_and_writing_images_and_video.html#videocapture-isopened">org.opencv.highgui.VideoCapture.isOpened</a>
*/
public boolean isOpened()
{
boolean retVal = n_isOpened(nativeObj);
return retVal;
}
//
// C++: bool VideoCapture::open(int device)
//
/**
* <p>Open video file or a capturing device for video capturing</p>
*
* <p>The methods first call "VideoCapture.release" to close the already opened
* file or camera.</p>
*
* @param device id of the opened video capturing device (i.e. a camera index).
*
* @see <a href="http://docs.opencv.org/modules/highgui/doc/reading_and_writing_images_and_video.html#videocapture-open">org.opencv.highgui.VideoCapture.open</a>
*/
public boolean open(int device)
{
boolean retVal = n_open(nativeObj, device);
return retVal;
}
//
// C++: bool VideoCapture::read(Mat image)
//
/**
* <p>Grabs, decodes and returns the next video frame.</p>
*
* <p>The methods/functions combine "VideoCapture.grab" and "VideoCapture.retrieve"
* in one call. This is the most convenient method for reading video files or
* capturing data from decode and return the just grabbed frame. If no frames
* has been grabbed (camera has been disconnected, or there are no more frames
* in video file), the methods return false and the functions return NULL
* pointer.</p>
*
* <p>Note: OpenCV 1.x functions <code>cvRetrieveFrame</code> and <code>cv.RetrieveFrame</code>
* return image stored inside the video capturing structure. It is not allowed
* to modify or release the image! You can copy the frame using "cvCloneImage"
* and then do whatever you want with the copy.</p>
*
* @param image a image
*
* @see <a href="http://docs.opencv.org/modules/highgui/doc/reading_and_writing_images_and_video.html#videocapture-read">org.opencv.highgui.VideoCapture.read</a>
*/
public boolean read(Mat image)
{
boolean retVal = n_read(nativeObj, image.nativeObj);
return retVal;
}
//
// C++: void VideoCapture::release()
//
/**
* <p>Closes video file or capturing device.</p>
*
* <p>The methods are automatically called by subsequent "VideoCapture.open" and
* by <code>VideoCapture</code> destructor.</p>
*
* <p>The C function also deallocates memory and clears <code>*capture</code>
* pointer.</p>
*
* @see <a href="http://docs.opencv.org/modules/highgui/doc/reading_and_writing_images_and_video.html#videocapture-release">org.opencv.highgui.VideoCapture.release</a>
*/
public void release()
{
n_release(nativeObj);
return;
}
//
// C++: bool VideoCapture::retrieve(Mat image, int channel = 0)
//
/**
* <p>Decodes and returns the grabbed video frame.</p>
*
* <p>The methods/functions decode and return the just grabbed frame. If no frames
* has been grabbed (camera has been disconnected, or there are no more frames
* in video file), the methods return false and the functions return NULL
* pointer.</p>
*
* <p>Note: OpenCV 1.x functions <code>cvRetrieveFrame</code> and <code>cv.RetrieveFrame</code>
* return image stored inside the video capturing structure. It is not allowed
* to modify or release the image! You can copy the frame using "cvCloneImage"
* and then do whatever you want with the copy.</p>
*
* @param image a image
* @param channel a channel
*
* @see <a href="http://docs.opencv.org/modules/highgui/doc/reading_and_writing_images_and_video.html#videocapture-retrieve">org.opencv.highgui.VideoCapture.retrieve</a>
*/
public boolean retrieve(Mat image, int channel)
{
boolean retVal = n_retrieve(nativeObj, image.nativeObj, channel);
return retVal;
}
/**
* <p>Decodes and returns the grabbed video frame.</p>
*
* <p>The methods/functions decode and return the just grabbed frame. If no frames
* has been grabbed (camera has been disconnected, or there are no more frames
* in video file), the methods return false and the functions return NULL
* pointer.</p>
*
* <p>Note: OpenCV 1.x functions <code>cvRetrieveFrame</code> and <code>cv.RetrieveFrame</code>
* return image stored inside the video capturing structure. It is not allowed
* to modify or release the image! You can copy the frame using "cvCloneImage"
* and then do whatever you want with the copy.</p>
*
* @param image a image
*
* @see <a href="http://docs.opencv.org/modules/highgui/doc/reading_and_writing_images_and_video.html#videocapture-retrieve">org.opencv.highgui.VideoCapture.retrieve</a>
*/
public boolean retrieve(Mat image)
{
boolean retVal = n_retrieve(nativeObj, image.nativeObj);
return retVal;
}
//
// C++: bool VideoCapture::set(int propId, double value)
//
/**
* Sets a property in the "VideoCapture".
*
* @param propId property identifier; it can be one of the following:
* * CV_CAP_PROP_FRAME_WIDTH width of the frames in the video stream.
* * CV_CAP_PROP_FRAME_HEIGHT height of the frames in the video stream.
* @param value value of the property.
*
* @see <a href="http://docs.opencv.org/modules/highgui/doc/reading_and_writing_images_and_video.html#videocapture-set">org.opencv.highgui.VideoCapture.set</a>
*/
public boolean set(int propId, double value)
{
boolean retVal = n_set(nativeObj, propId, value);
return retVal;
}
@Override
protected void finalize() throws Throwable {
n_delete(nativeObj);
super.finalize();
}
// C++: VideoCapture::VideoCapture()
private static native long n_VideoCapture();
// C++: VideoCapture::VideoCapture(string filename)
private static native long n_VideoCapture(java.lang.String filename);
// C++: VideoCapture::VideoCapture(int device)
private static native long n_VideoCapture(int device);
// C++: double VideoCapture::get(int propId)
private static native double n_get(long nativeObj, int propId);
// C++: bool VideoCapture::grab()
private static native boolean n_grab(long nativeObj);
// C++: bool VideoCapture::isOpened()
private static native boolean n_isOpened(long nativeObj);
// C++: bool VideoCapture::open(string filename)
private static native boolean n_open(long nativeObj, java.lang.String filename);
// C++: bool VideoCapture::open(int device)
private static native boolean n_open(long nativeObj, int device);
// C++: bool VideoCapture::read(Mat image)
private static native boolean n_read(long nativeObj, long image_nativeObj);
// C++: void VideoCapture::release()
private static native void n_release(long nativeObj);
// C++: bool VideoCapture::retrieve(Mat image, int channel = 0)
private static native boolean n_retrieve(long nativeObj, long image_nativeObj, int channel);
private static native boolean n_retrieve(long nativeObj, long image_nativeObj);
// C++: bool VideoCapture::set(int propId, double value)
private static native boolean n_set(long nativeObj, int propId, double value);
private static native String n_getSupportedPreviewSizes(long nativeObj);
// native support for java finalize()
private static native void n_delete(long nativeObj);
}