Programmatically generating an image

We can use the processImage function to generate an image without showing or loading the user interface.

Just like with the editor factory methods (openEditor, appendEditor, etc) we need to supply the processImage function with an imageReader to read image data and an imageWriter to write the output image (if we want to generate an output file).

import {
} from './doka.js';

// Create a square crop and scale down image without using the editor UI
processImage('./my-image.jpeg', {
    imageReader: createDefaultImageReader(),
    imageWriter: createDefaultImageWriter({
        targetSize: {
            width: 256,
            height: 256,
    imageCropAspectRatio: 1,
}).then(({ dest }) => {
    // Show resulting image preview
    const preview = new Image();
    preview.src = URL.createObjectURL(dest);