c# 图像格式png或bmp转换为ImageBGRA32

各位大咖，想要把一幅图片png格式或bmp格式转换为ImageBGRA32格式。
public ImageBGRA32(uint width, uint height, IntPtr imageData);

有帮助麻烦点个采纳【本回答右上角】，谢谢~~下面2张图为将原bgr32格式转换为bgra32的格式

//项目需要引用PresentationCore.dll和WindowsBase，然后导入下面3个ns
//using System.Windows.Media.Imaging;//需要引用PresentationCore.dll
//using System.Windows.Media;
//using System.IO;
//使用方式
//ImageToBGRA32(@"C:\Users\Admin\Desktop\图片\OBS_Bgra.jpg", @"C:\Users\Admin\Desktop\图片\OBS_Bgra32.jpg");
        public BitmapImage ImageToBitmapImage(string path)
        {
            using (Image img = new Bitmap(path)) 
            {
                using (var memory = new System.IO.MemoryStream())
                {
                    img.Save(memory, ImageFormat.Png);
                    memory.Position = 0;

                    var bitmapImage = new BitmapImage();
                    bitmapImage.BeginInit();//需要添加WindowsBase引用
                    bitmapImage.StreamSource = memory;
                    bitmapImage.CacheOption = BitmapCacheOption.OnLoad;
                    bitmapImage.EndInit();//需要添加WindowsBase引用

                    return bitmapImage;
                }
            }
        }
        /// <summary>
        /// 将目标图片转换为bgra32
        /// </summary>
        /// <param name="path">原图片</param>
        /// <param name="tpath">转换后图片保存物理路径</param>
        public void ImageToBGRA32(string path,string tpath)
        {
            BitmapImage bi = ImageToBitmapImage(path);
            if (bi.Format != PixelFormats.Bgra32)
            {
                FormatConvertedBitmap fcb = new FormatConvertedBitmap(bi, PixelFormats.Bgra32, null, 0);

                var pngBitmapEncoder = new PngBitmapEncoder();
                pngBitmapEncoder.Interlace = PngInterlaceOption.Off;
                pngBitmapEncoder.Frames.Add(BitmapFrame.Create(fcb));

                var memstream = new MemoryStream();
                pngBitmapEncoder.Save(memstream);
                memstream.Position = 0;


                var fs = new FileStream(tpath, FileMode.OpenOrCreate);
                var bw = new BinaryWriter(fs);
                bw.Write(memstream.ToArray());
                bw.Close();
                fs.Close();
            }
        }

参考：

SaveFileDialog sfd = new SaveFileDialog();
sfd.Title = "图象另存为";
sfd.OverwritePrompt = true;
sfd.CheckPathExists = true;
sfd.Filter = cmbSaveFiletype.Text + "|" + cmbSaveFiletype.Text;
sfd.ShowHelp = true;
if(sfd.ShowDialog() == DialogResult.OK)
{
string strFileName = sfd.FileName;
switch(cmbSaveFiletype.Text)
{
case "*.bmp":
m_bitmap.Save(strFileName, ImageFormat.Bmp);
break;

case "*.jpg":
m_bitmap.Save(strFileName, ImageFormat.Jpeg);
break;

case "*.gif":
m_bitmap.Save(strFileName, ImageFormat.Gif);
break;

case "*.tif":
m_bitmap.Save(strFileName, ImageFormat.Tiff);
break;
}
MessageBox.Show("图象文件格式转换成功！", "恭喜", MessageBoxButtons.OK, MessageBoxIcon.Exclamation);