Example #1
0
  @Override
  @SuppressWarnings("unchecked")
  public void perform(InputSocket<?>[] inputs, OutputSocket<?>[] outputs, Optional<?> data) {
    final Mat input = ((InputSocket<Mat>) inputs[0]).getValue().get();
    final Mat tmp = ((Optional<Mat>) data).get();
    final boolean externalOnly = ((InputSocket<Boolean>) inputs[1]).getValue().get();

    if (input.empty()) {
      return;
    }

    // findContours modifies its input, so we pass it a temporary copy of the input image
    input.copyTo(tmp);

    // OpenCV has a few different things it can return from findContours, but for now we only use
    // EXTERNAL and LIST.
    // The other ones involve hierarchies of contours, which might be useful in some situations, but
    // probably only
    // when processing the contours manually in code (so, not in a graphical pipeline).
    MatVector contours = new MatVector();
    findContours(
        tmp, contours, externalOnly ? CV_RETR_EXTERNAL : CV_RETR_LIST, CV_CHAIN_APPROX_TC89_KCOS);

    final OutputSocket<ContoursReport> contoursSocket = (OutputSocket<ContoursReport>) outputs[0];
    contoursSocket.setValue(new ContoursReport(contours, input.rows(), input.cols()));
  }