Question

我在从记忆中挽救形象方面有一些麻烦。

我的守则是:

MemoryStream ms = new MemoryStream(onimg);

if (ms.Length > 0)
{
    Bitmap bm = new Bitmap(ms);
    returnImage = (Image)bm.Clone();
}
ms.Close();
returnImage.Save(@"C:img.jpeg");

和<代码>。 Save i 但有以下例外:

在GDI+中出现了一种通用错误。

如果我没有填写<代码>。《记忆》全都是大韩民国,但在一段时间后需要大量记忆。

我如何能够这样做?

EDIT:T Savehat只是演示。我确实需要返回,以便把它放在可观察的Collection和窗户上展示,如果需要的话,它就会变成系统。

[ValueConversion(typeof(System.Drawing.Image), typeof(System.Windows.Media.ImageSource))]
public class ImageConverter : IValueConverter
{
    public object Convert(object value, Type targetType,
        object parameter, CultureInfo culture)
    {
            // empty images are empty...
            if (value == null) { return null; }

            var image = (System.Drawing.Image)value;
            // Winforms Image we want to get the WPF Image from...
            var bitmap = new System.Windows.Media.Imaging.BitmapImage();
            bitmap.BeginInit();
            MemoryStream memoryStream = new MemoryStream();
            // Save to a memory stream...
            image.Save(memoryStream, ImageFormat.Bmp);
            // Rewind the stream...
            memoryStream.Seek(0, System.IO.SeekOrigin.Begin);
            bitmap.StreamSource = memoryStream;
            bitmap.EndInit();
            return bitmap;
    }

    public object ConvertBack(object value, Type targetType,
        object parameter, CultureInfo culture)
    {
        return null;
    }
}

而XAML在这样做时也这样做。

<DataTemplate>
   <Image Width="32" Height="32" Source="{ Binding Thumb, Converter={StaticResource    imageConverter} }" />
</DataTemplate>

Answer 1

http://msdn.microsoft.com/en-us/library/z7ha67kw.aspx” rel=“nofollow noreferer”>

你们必须保持下游的开放性,使下游永久化。

比图需要在同一地方储存其数据,而我推断(尽管没有这方面的证据),<代码>Bitmap没有复制数据,而是使用溪流保持锁。

此外,没有证据表明<代码>。 Clone将产生新的标尺,并附上特稿。你的检验表明,情况并非如此。

Therefore, I am afraid you need to keep your stream open for the lifetime of your image. It requires memory, true, but otherwise if Bitmap copied the data, you will still need that memory for the bitmap representation. Therefore, no more memory is consumed with open stream (if my previous deduction was true).

If you really want to overcome the bitmap s dependency on the original memory stream, you will need to draw the orginal bitmap on the new one instead of cloning like here. But this will impact the performance, I would better re-analyze if it is not a good idea to keep the original stream, just making sure it is closed when bitmap is disposed.

Answer 2

Isn t a save to disk basically a clone?

using (MemoryStream ms = new MemoryStream(onimg))
{
    if (ms.Length > 0)
    {
        using (Bitmap bm = new Bitmap(ms))
        {
            bm.Save(@"C:img.jpeg");
        }
    }
}

友情链接