有很多方法可以解决这个问题。我过去用过几种。它与你使用图像的方式有很大的不同。你需要在图像上画一些东西还是仅仅显示它？
在我看来，使用CustomPainter可以最好地实现图像上的多帧。请查看documentation以了解更多信息。下面的画家应该可以做到这一点。

class TestPainter extends CustomPainter {
  final ui.Image image;

  TestPainter({required this.image});

  @override
  void paint(Canvas canvas, Size size) {
    //draw the image
    canvas.drawImage(image, const Offset(0, 0), Paint());

    double rectWidth = image.width.toDouble();
    double rectHeight = image.height.toDouble();
    final imageCenter = Offset(image.width / 2, image.height / 2);

    //first frame
    var border1 = Rect.fromCenter(
     center: imageCenter,
     width: rectWidth + 1,
     height: rectHeight + 1);

    var painting = Paint();
    painting.color = Colors.red;
    painting.strokeWidth = 2;
    painting.style = PaintingStyle.stroke;

    canvas.drawRect(border1, painting);

    //second frame
    var border2 = Rect.fromCenter(
     center: imageCenter,
     width: rectWidth + 3,
     height: rectHeight + 3);

    var painting2 = Paint();
    painting2.color = Colors.green;
    painting2.strokeWidth = 2;
    painting2.style = PaintingStyle.stroke;

    canvas.drawRect(
     border2,
     painting2,
    );
  }

  @override
  bool shouldRepaint(covariant CustomPainter oldDelegate) {
    return true;
  }
}

请注意。该示例中的图像需要是dar:ui library（Documentation）的图像。有多种转换方式。取决于您的项目。