react-webcamera/lib/index.js

React webcamera component with direct access to the camera data

'use strict';

Object.defineProperty(exports, "__esModule", {
  value: true
});

var _createClass = function () { function defineProperties(target, props) { for (var i = 0; i < props.length; i++) { var descriptor = props[i]; descriptor.enumerable = descriptor.enumerable || false; descriptor.configurable = true; if ("value" in descriptor) descriptor.writable = true; Object.defineProperty(target, descriptor.key, descriptor); } } return function (Constructor, protoProps, staticProps) { if (protoProps) defineProperties(Constructor.prototype, protoProps); if (staticProps) defineProperties(Constructor, staticProps); return Constructor; }; }();

var _react = require('react');

var _react2 = _interopRequireDefault(_react);

var _propTypes = require('prop-types');

var _propTypes2 = _interopRequireDefault(_propTypes);

function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { default: obj }; }

function _classCallCheck(instance, Constructor) { if (!(instance instanceof Constructor)) { throw new TypeError("Cannot call a class as a function"); } }

function _possibleConstructorReturn(self, call) { if (!self) { throw new ReferenceError("this hasn't been initialised - super() hasn't been called"); } return call && (typeof call === "object" || typeof call === "function") ? call : self; }

function _inherits(subClass, superClass) { if (typeof superClass !== "function" && superClass !== null) { throw new TypeError("Super expression must either be null or a function, not " + typeof superClass); } subClass.prototype = Object.create(superClass && superClass.prototype, { constructor: { value: subClass, enumerable: false, writable: true, configurable: true } }); if (superClass) Object.setPrototypeOf ? Object.setPrototypeOf(subClass, superClass) : subClass.__proto__ = superClass; }

CameraComponent.defaultProps = {
  demo: false
};

CameraComponent.propTypes = {
  demo: _propTypes2.default.bool,
  width: _propTypes2.default.number.isRequired,
  height: _propTypes2.default.number.isRequired,
  filter: _propTypes2.default.func

};

var CameraComponent = function (_Component) {
  _inherits(CameraComponent, _Component);

  function CameraComponent(props) {
    _classCallCheck(this, CameraComponent);

    var _this = _possibleConstructorReturn(this, (CameraComponent.__proto__ || Object.getPrototypeOf(CameraComponent)).call(this, props));

    _this.navigator = navigator;

    _this.pause = true;

    _this.draw = _this.draw.bind(_this);
    _this.drawToIntermediateCanvas = _this.drawToIntermediateCanvas.bind(_this);
    _this.drawToFinalCanvas = _this.drawToFinalCanvas.bind(_this);
    return _this;
  }

  _createClass(CameraComponent, [{
    key: 'setupGetMedia',
    value: function setupGetMedia() {
      this.navigator.getMedia = this.navigator.getUserMedia || this.navigator.webkitGetUserMedia || this.navigator.mozGetUserMedia || this.navigator.msGetUserMedia;
    }
  }, {
    key: 'startVideo',
    value: function startVideo(video) {
      // Show error message if camera is not supported by the browser
      if (!this.navigator.getMedia) {
        displayErrorMessage("Your browser doesn't have support for the navigator.getUserMedia interface.");
      } else {
        // Request the camera.
        this.navigator.getMedia({
          video: true
        },
        // Success Callback
        function (stream) {
          video.src = window.URL.createObjectURL(stream);
          video.play();
          video.onplay = function () {
            //showVideo();
          };
        },
        // Error Callback
        function (err) {
          console.error("There was an error with accessing the camera stream: " + err.name, err);
        });
      }
    }
  }, {
    key: 'setupCanvas',
    value: function setupCanvas() {
      this.canvas = this.refs.finalCanvas;
      this.context = this.canvas.getContext('2d');
      this.intermediateCanvas = this.refs.intermediateCanvas;
      this.intermediateContext = this.intermediateCanvas.getContext('2d');
    }
  }, {
    key: 'drawToIntermediateCanvas',
    value: function drawToIntermediateCanvas() {
      this.intermediateContext.drawImage(this.refs.cameraStream, 0, 0, this.props.width, this.props.height);
    }
  }, {
    key: 'drawToFinalCanvas',
    value: function drawToFinalCanvas(data) {
      this.context.putImageData(data, 0, 0);
    }
  }, {
    key: 'draw',
    value: function draw() {
      this.drawToIntermediateCanvas();

      //Apply filters/functions on the extracted video data
      var idata = this.getVideoData();
      var data = idata.data;

      var filteredData = void 0;
      var filteredImageData = idata;

      if (this.props.filter) {

        filteredData = this.props.filter(data);
        filteredImageData = new ImageData(filteredData, this.props.width, this.props.height);
      }

      this.drawToFinalCanvas(filteredImageData);
      setTimeout(this.draw, 80);
    }
  }, {
    key: 'getVideoData',
    value: function getVideoData() {
      var idata = this.intermediateContext.getImageData(0, 0, this.props.width, this.props.height);
      return idata;
    }
  }, {
    key: 'componentDidMount',
    value: function componentDidMount() {
      var video = this.refs.cameraStream;
      this.setupGetMedia();
      this.startVideo(video);

      this.setupCanvas();
    }
  }, {
    key: 'render',
    value: function render() {
      return _react2.default.createElement(
        'div',
        { className: 'camera' },
        _react2.default.createElement('video', { width: +this.props.width,
          height: +this.props.height,
          muted: true,
          hidden: true,
          ref: 'cameraStream',
          controls: true,
          onPlay: this.draw }),
        _react2.default.createElement('canvas', { width: +this.props.width,
          height: +this.props.height,
          hidden: !this.props.demo,
          ref: 'intermediateCanvas' }),
        _react2.default.createElement('canvas', { width: +this.props.width,
          height: +this.props.height,
          ref: 'finalCanvas' })
      );
    }
  }]);

  return CameraComponent;
}(_react.Component);

exports.default = CameraComponent;