performDetection method

Implementation

void performDetection() async {
  if (abort) return;

  /**************************/
  /* Cancel Detection Timer */
  /**************************/
  if (detectionTimer != null) detectionTimer!.cancel();

  /****************************/
  /* No New Frames to Detect? */
  /****************************/
  if (lastFrame != detectedFrame) {
    detectedFrame = lastFrame;
    try {
      if (widget.model.detectors != null) {
        int left = 0;
        int top = 0;
        int width = canvas.width!;
        int height = canvas.height!;
        if ((width + left) > canvas.width!) width = canvas.width! - left;
        if ((height + top) > canvas.height!) height = canvas.height! - top;

        /*************************/
        /* Get Image RGBA Bitmap */
        /*************************/
        HTML.ImageData image =
            canvas.context2D.getImageData(left, top, width, height);
        List<int> rgba = image.data.toList();

        /************************/
        /* Convert to Grayscale */
        /************************/
        //rgba = ImageHelper.toGrayScale(rgba);

        //var list8 = Uint8List.fromList(rgba);

        //UriData uri = UriData.parse(canvas.toDataUrl('image/png',1.0));
        //Uint8List bytz = uri.contentAsBytes();

        //IMAGE.Image original = IMAGE.decodePng(bytz);
        //img = IMAGE.grayscale(img);
        //img = IMAGE.gaussianBlur(img, 2);
        //img = IMAGE.contrast(img, 125);
        //img = IMAGE.invert(img);

        if (widget.model.debug == true) {
          var bytes = Uint8List.fromList(rgba);
          for (int i = 0; i < bytes.length; i++) image.data[i] = bytes[i];
          canvas2.width = width;
          canvas2.height = height;
          canvas2.context2D.putImageData(image, 0, 0);
          HTML.Blob blob = await canvas2.toBlob('image/png', 1.0);
          await Platform.fileSaveAsFromBlob(blob, "${S.newId()}-.png");
        }

        // process stream image
        onStream(rgba, width, height);
      }
    } catch(e) {
      //DialogService().show(type: DialogType.error, title: 'detecting error2');
    }
  }

  /***************************/
  /* Schedule Next Detection */
  /***************************/
  detectionTimer = Timer(Duration(milliseconds: 50), performDetection);
}