Untitled 2/15/2018 4:22:09 PM
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>Background Subtraction Example</title>
<link href="js_example_style.css" rel="stylesheet" type="text/css" />
</head>
<body>
<h2>Background Subtraction Example</h2>
<p>
</p>
<div>
<div class="control"><button id="startAndStop" disabled>Start</button></div>
<textarea class="code" rows="29" cols="80" id="codeEditor" spellcheck="false">
</textarea>
</div>
<p class="err" id="errorMessage"></p>
<div>
<table cellpadding="0" cellspacing="0" width="0" border="0">
<tr>
<td>
<video id="videoInput" width="900" height="900" muted loop></video>
</td>
<td>
<canvas id="canvasOutput" width="320" height="240"></canvas>
</td>
<td></td>
<td></td>
</tr>
<tr>
<td>
<div class="caption">videoInput</div>
</td>
<td>
<div class="caption">canvasOutput</div>
</td>
<td></td>
<td></td>
</tr>
</table>
</div>
<script src="adapter-5.0.4.js" type="text/javascript"></script>
<script src="utils.js" type="text/javascript"></script>
<script id="codeSnippet" type="text/code-snippet">
let video = document.getElementById('videoInput');
let cap = new cv.VideoCapture(video);
let frame = new cv.Mat(video.height, video.width, cv.CV_8UC4);
let fgmask = new cv.Mat(video.height, video.width, cv.CV_8UC1);
let fgbg = new cv.BackgroundSubtractorMOG2(500, 16,false );
const FPS = 30;
function processVideo() {
try {
if (!streaming) {
// clean and stop.
frame.delete(); fgmask.delete(); fgbg.delete();
return;
}
let begin = Date.now();
// start processing.
cap.read(frame);
fgbg.apply(frame, fgmask);
frame.copyTo(fgmask, fgmask);
cv.imshow('canvasOutput', fgmask);
// schedule the next one.
let delay = 1000/FPS - (Date.now() - begin);
setTimeout(processVideo, delay);
} catch (err) {
utils.printError(err);
}
};
// schedule the first one.
setTimeout(processVideo, 0);
</script>
<script type="text/javascript">
let utils = new Utils('errorMessage');
utils.loadCode('codeSnippet', 'codeEditor');
let streaming = false;
let videoInput = document.getElementById('videoInput');
let startAndStop = document.getElementById('startAndStop');
let canvasOutput = document.getElementById('canvasOutput');
let canvasContext = canvasOutput.getContext('2d');
startAndStop.addEventListener('click', () => {
if (!streaming) {
utils.clearError();
videoInput.play().then(() => {
onVideoStarted();
});
} else {
videoInput.pause();
videoInput.currentTime = 0;
onVideoStopped();
}
});
function onVideoStarted() { //Start image processing on video
videoInput.onload=function()
{
streaming = true;
startAndStop.innerText = 'Stop';
videoInput.height = videoInput.width * (videoInput.videoHeight / videoInput.videoWidth);
canvasContext.height=videoInput.height;
canvasContext.width=videoInput.width;
utils.executeCode('codeEditor');
};
}
function onVideoStopped() {
streaming = false;
canvasContext.clearRect(0, 0, videoInput.width, videoInput.height);
startAndStop.innerText = 'Start';
}
utils.loadOpenCv(() => {
videoInput.addEventListener('canplay', () => {
startAndStop.removeAttribute('disabled');
});
videoInput.src = 'box.mp4';
});
</script>
</body>
</html>
Public Last updated: 2018-02-15 04:35:46 PM
