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2025-11-20 15:27:34 -06:00

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<!--
Copyright 2013, 2016, 2019 IBM Corp.
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
-->
<script type="text/x-red" data-template-name="camera">
<div class="form-row">
<label for="node-input-name"><i class="fa fa-tag"></i> Name</label>
<input type="text" id="node-input-name" placeholder="Camera">
</div>
</script>
<script type="text/x-red" data-help-name="camera">
<p>A simple camera node to capture the current image from the device webcam</p>
<p>Usage:</p>
<ol>
<li>Add the camera node to your flow</li>
<li>Click the <code>button</code> capture an image from the webcam</li>
</ol>
<p>The <code>png</code> image is sent as the <code>msg.payload</code> object</p>
<p>Supported browsers</p>
<ul>
<li>Chrome</li>
<li>Firefox</li>
</ul>
</script>
<script type="text/javascript">
(function() {
navigator.getUserMedia = navigator.getUserMedia || navigator.webkitGetUserMedia || navigator.mozGetUserMedia || navigator.msGetUserMedia;
window.URL = window.URL || window.webkitURL || window.mozURL || window.msURL;
window.video = document.createElement('video')
window.canvas = document.createElement('canvas')
canvas.style.display = 'none'
canvas.style.display = 'none'
var id
function onCanPlay(evt) {
video.removeEventListener('canplay', onCanPlay, false)
var width = 320
var height = video.videoHeight / (video.videoWidth / width)
if (isNaN(height)) {
height = width / (4 / 3)
}
setTimeout(function(evt) {
video.setAttribute('width', width)
video.setAttribute('height', height)
canvas.setAttribute('width', width)
canvas.setAttribute('height', height)
var ctx = canvas.getContext('2d')
ctx.drawImage(video, 0, 0, width, height)
canvas.toBlob(function(blob) {
uploadRecord(id, blob)
})
}, 2000)
}
function onStreamReady(id, stream) {
// As of Chrome 71 createObjectURL is dropped so try direct
// access first
// https://developer.mozilla.org/en-US/docs/Web/API/HTMLMediaElement/srcObject
try {
video.srcObject = stream;
} catch (error) {
video.src = window.URL.createObjectURL(stream)
}
video.addEventListener('canplay', onCanPlay, false)
video.play()
}
function onVideoPlaying(id, evt) {
canvas.style.height = video.clientHeight + 'px'
canvas.style.width = video.clientWidth + 'px'
var ctx = canvas.getContext('2d')
ctx.drawImage(video, 0, 0)
canvas.toBlob(function(blob) {
uploadRecord(id, blob)
})
}
function setCameraStatus(record, id) {
$.getJSON('node-red-camera/status', {status: record, id: id})
.done(function () {})
.fail(function (err) {
console.log(err);
})
.always(function () {});
}
function takeSnapshot(id) {
const constraints = {video : true, audio : false};
navigator.mediaDevices.getUserMedia(constraints)
.then(function(stream) {
setCameraStatus(true, id)
onStreamReady(id, stream)
})
.catch(function(err) {
window.alert('Your browser does not support the camera node')
console.log(err)
})
}
function uploadRecord(id, blob) {
var xhr = new XMLHttpRequest()
xhr.open('POST', 'node-red-camera/' + id, true)
xhr.send(blob)
}
RED.nodes.registerType('camera', {
category: 'input',
defaults: {
name: {value: ''}
},
color: 'rgb(215, 201, 194)',
inputs: 0,
outputs: 1,
icon: 'camera.png',
paletteLabel: 'camera',
label: function() {
return this.name || 'camera';
},
labelStyle: function() {
return this.name ? 'node_label_italic' : '';
},
button: {
onclick: function(){
id = this.id
takeSnapshot(id)
}
}
});
})();
</script>