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bmp-converter.js
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bmp-converter.js
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export default bmpImage => new Promise(resolve => {
// If the input is an ArrayBuffer, we need to convert it to a `Blob` and give it a URL so we can use it as an <img>
// `src`. If it's a data URI, we can use it as-is.
const imageUrl = bmpImage instanceof String ?
bmpImage :
window.URL.createObjectURL(new Blob([bmpImage], {type: 'image/bmp'}));
const canvas = document.createElement('canvas');
const ctx = canvas.getContext('2d');
const image = document.createElement('img');
image.addEventListener('load', () => {
canvas.width = image.naturalWidth;
canvas.height = image.naturalHeight;
ctx.drawImage(image, 0, 0);
const dataUrl = canvas.toDataURL('image/png');
// Revoke URL. If a blob URL was generated earlier, this allows the blob to be GC'd and prevents a memory leak.
window.URL.revokeObjectURL(imageUrl);
resolve(dataUrl);
});
image.setAttribute('src', imageUrl);
});