export function replaceWhiteWithTransparent(imageBase64: string): Promise { return new Promise((resolve, reject) => { const img = new Image(); img.onload = () => { const canvas = document.createElement('canvas'); canvas.width = img.width; canvas.height = img.height; const ctx = canvas.getContext('2d'); if (!ctx) { reject('Unable to get canvas 2D context'); return; } ctx.drawImage(img, 0, 0); const imageData = ctx.getImageData(0, 0, canvas.width, canvas.height); const data = imageData.data; for (let i = 0; i < data.length; i += 4) { if (data[i] === 255 && data[i + 1] === 255 && data[i + 2] === 255) { data[i + 3] = 0; } } ctx.putImageData(imageData, 0, 0); resolve(canvas.toDataURL()); }; img.onerror = (err) => { reject(err); }; img.src = imageBase64; }); }