// Copyright (c) 2015-2016 The Regents of the University of California.
// All rights reserved.
//
// Permission is hereby granted, without written agreement and without
// license or royalty fees, to use, copy, modify, and distribute this
// software and its documentation for any purpose, provided that the above
// copyright notice and the following two paragraphs appear in all copies
// of this software.
//
// IN NO EVENT SHALL THE UNIVERSITY OF CALIFORNIA BE LIABLE TO ANY PARTY
// FOR DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
// ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN IF
// THE UNIVERSITY OF CALIFORNIA HAS BEEN ADVISED OF THE POSSIBILITY OF
// SUCH DAMAGE.
//
// THE UNIVERSITY OF CALIFORNIA SPECIFICALLY DISCLAIMS ANY WARRANTIES,
// INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
// MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE
// PROVIDED HEREUNDER IS ON AN "AS IS" BASIS, AND THE UNIVERSITY OF
// CALIFORNIA HAS NO OBLIGATION TO PROVIDE MAINTENANCE, SUPPORT, UPDATES,
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//
/** A motion detector accessor.
* This accessor compares each input image against the previous
* input image. There are three outputs.
* The one named 'output' is a modified image that graphically illustrates
* the center of gravity of motion, if motion is detected.
* If enough of the pixels differ by enough, then the 'cog'
* output will produce the center of gravity of the pixels that
* differ by enough.
* Finally, the 'area' output produces the percentage of area
* covered by motion in the input image, where 0 means no motion
* and 100 means full image motion.
*
* The options parameter can include the following fields:
* * _PixelThreshold_: Intensity threshold whereby a pixel is
* deemed to different (an int in the range of 0 to 255, with default 25).
* * _AreaThreshold_: The percentage threshold of image
* that has different pixels for motion to be detected
* (a double 0-100, with default 0.2).
* * _ModifyImage_: If true (the default), the modify the
* provided image with a visual indication of the location
* and amount of motion.
*
* The implementation for the Ptolemy II host is taken from
* the webcam-capture package by Bartosz Firyn (SarXos), available from
* [https://github.com/sarxos/webcam-capture](https://github.com/sarxos/webcam-capture).
* The webcam-capture package is licensed under the MIT License.
*
* @accessor image/MotionDetector
* @input input A stream of images.
* @input {{"PixelThreshold": number, "AreaThreshold": number}} options The options controlling the filter.
* @output {array<{'horizontal': 'number', 'vertical': 'number'}>} cog The horizontal and vertical position of the center of gravity of motion, in pixels.
* @output {Object} output The filtered image.
* @output {number} area The percentage of area covered by motion.
* @author Edward A. Lee
* @version $$Id$$
*/
// Stop extra messages from jslint. Note that there should be no
// space between the / and the * and global.
/*globals addInputHandler, exports, get, getParameter, input, output, removeInputHandler, require, send */
/*jshint globalstrict: true */
"use strict";
var motionDetector = require('motionDetector');
exports.setup = function () {
this.input('input');
this.output('output');
this.output('cog');
this.output('area', {
'type': 'number'
});
this.input('options', {
'value': '{"PixelThreshold": 25, "AreaThreshold": 0.2}',
'type': 'JSON'
});
};
exports.initialize = function () {
this.addInputHandler('input', function () {
var options = this.get('options');
var image = this.get('input');
var result = motionDetector.filter(image, options);
this.send('output', result);
var cog = motionDetector.cog();
if (cog) {
this.send('cog', cog);
}
this.send('area', motionDetector.area());
});
};