OpenCV

OpenCV

The opencv module is the root of the node-opencv package.

Accessing:

var cv = require('opencv');

give an OpenCV object.

Functions provided in the root module:

note: none of the below are actually asynchronous at the time of writing this wiki article

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cv.readImage( imagefilename:String, function( err, img ){} )

Reads an image from disk using cv::imread(filename, CV_LOAD_IMAGE_UNCHANGED)

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cv.readImage( imagedata:Buffer, function( err, img ){} )

Decodes an image from a Buffer using cv::imdecode(*mbuf, CV_LOAD_IMAGE_UNCHANGED)

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cv.readImage( width:number, height:number, function( err, img ){} )

creates a Matrix of the specified size and of type CV_64FC1. currently not operational because arg 2 has to be a function!

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cv.readImageMulti( imagefilename:String, function( err, arr ){} )

Reads a file containing multiple images and calls back with an array of Matrix objects using cv::imreadmulti(filename, mats);

Does nothing and returns false in openCV < 3.

Returns undefined (? - untested) in OpenCV3.

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Modules added to the root module:

Modules in node-opencv are added to OpenCV according to their availability at compile time.

init.cc is responsible for calling the code to add modules; the basic list is:

  Point::Init(target);
  Matrix::Init(target);
#ifdef HAVE_OPENCV_OBJDETECT
  CascadeClassifierWrap::Init(target);
#endif
#ifdef HAVE_OPENCV_VIDEOIO
  VideoCaptureWrap::Init(target);
  VideoWriterWrap::Init(target);
#endif
  Contour::Init(target);
#ifdef HAVE_OPENCV_VIDEO
  TrackedObject::Init(target);
#endif
#ifdef HAVE_OPENCV_HIGHGUI
  NamedWindow::Init(target);
#endif
  Constants::Init(target);
#ifdef HAVE_OPENCV_CALIB3D
  Calib3D::Init(target);
#endif
#ifdef HAVE_OPENCV_IMGPROC
  ImgProc::Init(target);
  Histogram::Init(target);
#endif
#if CV_MAJOR_VERSION < 3
  StereoBM::Init(target);
  StereoSGBM::Init(target);
  StereoGC::Init(target);

#if CV_MAJOR_VERSION == 2 && CV_MINOR_VERSION >=4
  #ifdef HAVE_OPENCV_FEATURES2D
    Features::Init(target);
  #endif
  LDAWrap::Init(target);
#endif
#endif
#ifdef HAVE_BACKGROUNDSUBTRACTOR
  BackgroundSubtractorWrap::Init(target);
#endif
#ifdef HAVE_OPENCV_FACE
  FaceRecognizerWrap::Init(target);
#endif

Each of these in general terms adds an object with methods to OpenCV;

For example, Matrix can be accessed like:

var mtx = new cv.Matrix();

Each module should have a separate page on the wiki (WIP).