async function convertAvifToJpg(file, quality = 0.9) {
  return new Promise((resolve, reject) => {
      const canvas = document.createElement('canvas');
      const ctx = canvas.getContext('2d');
      const img = new Image();
      
      img.onload = function() {
          // Set canvas dimensions
          canvas.width = img.width;
          canvas.height = img.height;
          
          // Draw image
          ctx.drawImage(img, 0, 0);
          
          // Convert to JPG
          canvas.toBlob(resolve, 'image/jpeg', quality);
      };
      
      img.onerror = reject;
      img.src = URL.createObjectURL(file);
  });
}

// Usage example
const fileInput = document.getElementById('file-input');
fileInput.addEventListener('change', async (e) => {
  const file = e.target.files[0];
  if (file && file.type === 'image/avif') {
      try {
          const jpgBlob = await convertAvifToJpg(file, 0.9);
          // Download converted file
          const url = URL.createObjectURL(jpgBlob);
          const a = document.createElement('a');
          a.href = url;
          a.download = file.name.replace('.avif', '.jpg');
          a.click();
      } catch (error) {
          console.error('Conversion failed:', error);
      }
  }
});