如何在将BitmapImage转换为字节后清除内存

using System;
using System.IO;
using System.Windows.Media.Imaging;

public class BitmapImageMemoryCleanup
{
    public static byte[] ConvertBitmapImageToBytes(BitmapImage bitmapImage)
    {
        byte[] bytes;

        using (MemoryStream stream = new MemoryStream())
        {
            BitmapEncoder encoder = new PngBitmapEncoder();
            encoder.Frames.Add(BitmapFrame.Create(bitmapImage));
            encoder.Save(stream);
            bytes = stream.ToArray();
        }

        return bytes;
    }

    public static void CleanupBitmapImage(BitmapImage bitmapImage)
    {
        bitmapImage = null; // 解除引用，使对象成为垃圾回收的候选项
        GC.Collect(); // 触发垃圾回收
        GC.WaitForPendingFinalizers(); // 等待所有终结器完成
    }
}

// 使用示例
BitmapImage image = new BitmapImage(new Uri("image.png", UriKind.Relative));
byte[] bytes = BitmapImageMemoryCleanup.ConvertBitmapImageToBytes(image);
BitmapImageMemoryCleanup.CleanupBitmapImage(image);