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updated README
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README.md

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@@ -82,6 +82,8 @@ Different OpenCV 3.x base images can be found here: https://hub.docker.com/r/jus
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## Usage with Electron
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### [opencv-electron](https://github.com/justadudewhohacks/opencv-electron) - example for opencv4nodejs with electron
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Add the following script to your package.json:
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``` python
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"electron-rebuild": "electron-rebuild -w opencv4nodejs"
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### Drawing a Mat into HTML Canvas
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``` javascript
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const matBGR = ...;
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// convert your Mat to rgba space
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const matRGBA = matBGR.cvtColor(cv.COLOR_BGR2RGBA);
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// get raw Mat data
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const matDataRaw = matRGBA.getData();
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const img = ...
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// convert your image to rgba color space
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const matRGBA = img.channels === 1
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? img.cvtColor(cv.COLOR_GRAY2RGBA)
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: img.cvtColor(cv.COLOR_BGR2RGBA);
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// create new ImageData from raw mat data
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const imgData = new ImageData(
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new Uint8ClampedArray(matRGBA.getData()),
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img.cols,
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img.rows
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);
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// fill canvas pixels
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// set canvas dimensions
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const canvas = document.getElementById('myCanvas');
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canvas.height = img.rows;
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canvas.width = img.cols;
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// set image data
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const ctx = canvas.getContext('2d');
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const imgData = ctx.getImageData(0, 0, matRGBA.cols, matRGBA.rows);
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for (let i = 0; i < matDataRaw.length; i += 1) {
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imgData.data[i] = matDataRaw[i];
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}
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ctx.putImageData(imgData, 0, 0);
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```
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package.json

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"learning"
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],
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"author": "justadudewhohacks",
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"license": "ISC",
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"license": "MIT",
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"repository": {
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"type": "git",
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"url": "git+https://github.com/justadudewhohacks/opencv4nodejs"

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