CameraCapture
Prerequisites:
- bonsai Vision Library
Category: Source
Brief: Acquires a sequence of images from a DirectShow-compatible camera with the specified index.
Properties:
CaptureProperties(Bonsai.Vision.CapturePropertyCollection) - OpenCV capture properties, which can be set by opening the CapturePropertyAssignment Collection Editor and adding a new memberProperty- a drop-down list of OpenCV capture properties; whether a given property is configurable depends on the particular cameraValue- value of the selected property
Index(int) - index of the camera to acquire images from
Output (OpenCV.Net.IpIImage) - 2D matrix of pixels, accepted as input by VideoWriter
IsInvalid(bool)ElementType(int)Size(OpenCV.Net.Size)Width(int)Height(int)
Depth(OpenCV.Net.IpIDepth)Channels(int)Width(int)Height(int)WidthStep(int)ImageData(System.IntPtr)ChannelOfInterest(int)RegionOfInterest(OpenCV.Net.Rect)X(int)Y(int)Width(int)Height(int)
IsClosed(bool)
tip
Write video to file using VideoWriter
tip
To visualise the video during acquisition, install the bonsai Vision Design Library and open Bonsai.Vision.Design.IplImageVisualizerfrom the CameraCapture node
tip
If CameraCapture acquires frames at a high rate and is followed by a long processing pipeline, processing delays may result in dropped frames. This is because CameraCapture can only stream a new frame once the downstream processing of the previous frame has completed. Up to a limit, this issue can be solved by including buffers.
tip
For industrial cameras, use dedicated Bonsai libraries:
| Camera | Bonsai |
|---|---|
Basler | Pylon Library |
FLIR | Spinnaker Library |
Intel RealSense | RealSense Library |
PCO | PCO Library* |
PointGrey | PointGrey Library |
PSEye | CLEyeMulticam Library |
uEye | uEye Library |
- PCO library is not distributed yet (as of Dec'20), but can be compiled from the github repository.
caution
Runtime error: Unable to acquire camera frame
One possible reason is that the camera is currently open in another software.