export function compressBase64Image(base64Image, compressionRatio) { return new Promise((resolve, reject) => { const img = new Image(); img.src = base64Image; img.onload = function() { const canvas = document.createElement('canvas'); canvas.width = img.width * compressionRatio; canvas.height = img.height * compressionRatio; const ctx = canvas.getContext('2d'); ctx.drawImage(img, 0, 0, canvas.width, canvas.height); // 将Canvas上的图像转换为PNG格式的Base64 const compressedBase64 = canvas.toDataURL('image/png', 1); resolve(compressedBase64); }; img.onerror = function() { reject("无法加载图像"); }; }); }