c# 二进制图片图片还原颜色失真

[ZHANGWENDY]

SqlConnection conn = new SqlConnection(@"data source=.;uid=sa;pwd=.;database=test");
conn.Open();
String str = "";
SqlCommand cmd = new SqlCommand("select top 1 photo from PicTestZyz", conn);
SqlDataReader reader = cmd.ExecuteReader();
byte[] bt;
while (reader.Read())
{
for (int i = 0; i < reader.FieldCount; i++)
{
bt = (byte[])reader[i];
str = Encoding.ASCII.GetString(bt);
str = str.Substring(str.IndexOf("BM"), str.Length - str.IndexOf("BM"));
bt = Encoding.ASCII.GetBytes(str);
MemoryStream buf = new MemoryStream(bt);
Bitmap mp = (Bitmap)Bitmap.FromStream(buf, true, true);
mp = RePic(mp, mp.Width, mp.Height);
mp.Save(@"C:\Data\a.jpg", System.Drawing.Imaging.ImageFormat.jpeg);
this.pictureBox1.Image = mp;
}
}

[ZHANGWENDY]

忘记描述问题了
图片是通过Access转成二进制存入数据库的,现在通过C#还原时颜色已严重失真;
如:

[gxingmin]

RePic函数干了什么？ System.Drawing.Imaging.ImageFormat.jpeg格式是不是和当初原图格式不一致了

[ZHANGWENDY]

mp = RePic(mp, mp.Width, mp.Height); 需屏蔽

[ZHANGWENDY]

试了多种文件格式都是一样

[zhoujk]

格式应该是 ABGR，其中后三位才是有效的，第一位是透明通道。MS你装错位置了？

[ZHANGWENDY]

各位大虾都过来帮忙看看啊

[ZHANGWENDY]

原始图片

[assky124]

你存数据库的时候编码了？存的时候有没有失真啊？ 把不必要的代码全注释掉，手动调试下

  bt = (byte[])reader[i];
  //str = Encoding.ASCII.GetString(bt);
  //str = str.Substring(str.IndexOf("BM"), str.Length - str.IndexOf("BM"));
  //bt = Encoding.ASCII.GetBytes(str);
  MemoryStream buf = new MemoryStream(bt);
  Bitmap mp = (Bitmap)Bitmap.FromStream(buf, true, true);
  //mp = RePic(mp, mp.Width, mp.Height);
  //mp.Save(@"C:\Data\a.jpg", System.Drawing.Imaging.ImageFormat.jpeg);
  this.pictureBox1.Image = mp;

[ZHANGWENDY]

不好意思 不太明白你的意思

[maxldwy]

 private void BindingImageSource(byte[] _imgByte)//显示image
        {
            /*6. 将二进制转化为Imagesource，在Image上显示*/
            ImageSource imgSource = ChangeBitmapToBitmapSource(SetByteToBitmap(_imgByte));
            image1.Source = imgSource;
        }
 public static BitmapSource ChangeBitmapToBitmapSource(Draw.Bitmap bmp)
        {
            BitmapSource returnSource = null;
            try
            {
                returnSource = System.Windows.Interop.Imaging.CreateBitmapSourceFromHBitmap(bmp.GetHbitmap(), IntPtr.Zero, Int32Rect.Empty, BitmapSizeOptions.FromEmptyOptions());
            }
            catch
            {
                returnSource = null;
            }
            return returnSource;
        }
        public Draw.Bitmap SetByteToBitmap(byte[] mybyte)
        {
            MemoryStream stream = new MemoryStream(mybyte);
            return new Draw.Bitmap(stream);
        }

[ZHANGWENDY]

效果是一样的. 原来是用Access保存到数据库的, 用的是OLE objects. str = Encoding.ASCII.GetString(bt); str = str.Substring(str.IndexOf("BM"), str.Length - str.IndexOf("BM")); bt = Encoding.ASCII.GetBytes(str); 这里这样处理是因为前面加了一些字节,不去掉无法还原成图片的.