convertUiImageToBytes function

Future<Uint8List?> convertUiImageToBytes(
  1. Image image, {
  2. ImageCompressionConfig? compression,
})

将 ui.Image 转换为 Uint8List，默认输出 PNG

Implementation

Future<Uint8List?> convertUiImageToBytes(
  ui.Image image, {
  ImageCompressionConfig? compression,
}) async {
  final ImageCompressionConfig effectiveConfig =
      compression ?? const ImageCompressionConfig();

  final double scale = effectiveConfig.scale ?? 1.0;
  ui.Image targetImage = image;
  ui.Image? resizedImage;

  if (effectiveConfig.enabled && scale > 0 && scale < 1.0) {
    final int targetWidth = math.max(1, (image.width * scale).round());
    final int targetHeight = math.max(1, (image.height * scale).round());
    if (targetWidth != image.width || targetHeight != image.height) {
      resizedImage = await _resizeImage(image, targetWidth, targetHeight);
      targetImage = resizedImage;
    }
  }

  final ByteData? byteData =
      await targetImage.toByteData(format: effectiveConfig.format);

  if (resizedImage != null) {
    _disposeImage(resizedImage);
  }

  if (byteData == null) {
    return null;
  }
  return byteData.buffer.asUint8List();
}