 | VideoCapture Methods |
The VideoCapture type exposes the following members.
Methods| Name | Description | |
|---|---|---|
 | AllocGCHandle |
Pins the object to be allocated by cvSetData.
(Inherited from DisposableObject.) |
| AllocMemory |
Allocates the specified size of memory.
(Inherited from DisposableObject.) |
 | Dispose |
Releases the resources
(Inherited from DisposableObject.) |
| Dispose(Boolean) |
Releases the resources
(Inherited from DisposableObject.) |
| DisposeManaged |
Releases managed resources
(Inherited from DisposableObject.) |
| DisposeUnmanaged |
Releases unmanaged resources
(Overrides DisposableCvObjectDisposeUnmanaged.) |
| Equals | Determines whether the specified object is equal to the current object. (Inherited from Object.) |
| Finalize |
Destructor
(Inherited from DisposableObject.) |
 | FromCamera |
Opens a camera for video capturing
|
| FromFile |
Opens a video file or a capturing device or an IP video stream for video capturing with API Preference
|
| Get(Int32) |
Returns the specified VideoCapture property
|
| Get(VideoCaptureProperties) |
Returns the specified VideoCapture property
|
| GetBackendName |
Returns used backend API name.
Note that stream should be opened.
|
| GetExceptionMode |
query if exception mode is active
|
| GetHashCode | Serves as the default hash function. (Inherited from Object.) |
| GetType | Gets the Type of the current instance. (Inherited from Object.) |
| Grab |
Grabs the next frame from video file or capturing device.
The method/function grabs the next frame from video file or camera and returns true (non-zero) in the case of success.
The primary use of the function is in multi-camera environments, especially when the cameras do not
have hardware synchronization. That is, you call VideoCapture::grab() for each camera and after that
call the slower method VideoCapture::retrieve() 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.
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 channel parameter.
|
| IsOpened |
Returns true if video capturing has been initialized already.
|
| MemberwiseClone | Creates a shallow copy of the current Object. (Inherited from Object.) |
| NotifyMemoryPressure |
Notifies the allocated size of memory.
(Inherited from DisposableObject.) |
| Open(Int32, VideoCaptureAPIs) |
Opens a camera for video capturing
|
| Open(String, VideoCaptureAPIs) |
Opens a video file or a capturing device or an IP video stream for video capturing.
|
| Read(Mat) |
Grabs, decodes and returns the next video frame.
The method/function combines VideoCapture::grab() and VideoCapture::retrieve() in one call. This is the
most convenient method for reading video files or capturing data from decode and returns the just
grabbed frame. If no frames has been grabbed (camera has been disconnected, or there are no more
frames in video file), the method returns false and the function returns empty image (with %cv::Mat, test it with Mat::empty()).
|
| Read(OutputArray) |
Grabs, decodes and returns the next video frame.
The method/function combines VideoCapture::grab() and VideoCapture::retrieve() in one call. This is the
most convenient method for reading video files or capturing data from decode and returns the just
grabbed frame. If no frames has been grabbed (camera has been disconnected, or there are no more
frames in video file), the method returns false and the function returns empty image (with %cv::Mat, test it with Mat::empty()).
|
| Release |
Closes video file or capturing device.
|
| Retrieve(Mat, CameraChannels) |
Decodes and returns the grabbed video frame.
The method decodes and returns the just grabbed frame. If no frames has been grabbed
(camera has been disconnected, or there are no more frames in video file), the method returns false
and the function returns an empty image (with %cv::Mat, test it with Mat::empty()).
|
| Retrieve(Mat, Int32) |
Decodes and returns the grabbed video frame.
The method decodes and returns the just grabbed frame. If no frames has been grabbed
(camera has been disconnected, or there are no more frames in video file), the method returns false
and the function returns an empty image (with %cv::Mat, test it with Mat::empty()).
|
| Retrieve(OutputArray, CameraChannels) |
Decodes and returns the grabbed video frame.
The method decodes and returns the just grabbed frame. If no frames has been grabbed
(camera has been disconnected, or there are no more frames in video file), the method returns false
and the function returns an empty image (with %cv::Mat, test it with Mat::empty()).
|
| Retrieve(OutputArray, Int32) |
Decodes and returns the grabbed video frame.
The method decodes and returns the just grabbed frame. If no frames has been grabbed
(camera has been disconnected, or there are no more frames in video file), the method returns false
and the function returns an empty image (with %cv::Mat, test it with Mat::empty()).
|
| RetrieveMat |
Decodes and returns the grabbed video frame.
The method decodes and returns the just grabbed frame. If no frames has been grabbed
(camera has been disconnected, or there are no more frames in video file), the method returns false
and the function returns an empty image (with %cv::Mat, test it with Mat::empty()).
|
| Set(Int32, Double) |
Sets a property in the VideoCapture.
|
| Set(VideoCaptureProperties, Double) |
Sets a property in the VideoCapture.
|
| SetExceptionMode |
Switches exceptions mode.
methods raise exceptions if not successful instead of returning an error code
|
| ThrowIfDisposed |
If this object is disposed, then ObjectDisposedException is thrown.
(Inherited from DisposableObject.) |
| ToString | Returns a string that represents the current object. (Inherited from Object.) |
See Also