I have a Image control inside my wpf application, which has a large image inside of it, but the control itself is only 60x150, this means it only shows a certain portion of this image. What is the easiest way of saving the visible portion to a file?
Thank you for your help.
[EDIT] I ended up using code found here (which I've not been able to locate before posting here)...
Grid r = new Grid();
r.Background = new ImageBrush(image2.Source);
System.Windows.Size sz = new System.Windows.Size(image2.Source.Width, image2.Source.Height);
r.Measure(sz);
r.Arrange(new Rect(sz));
RenderTargetBitmap rtb = new RenderTargetBitmap((int)image2.Source.Width, (int)image2.Source.Height, 96d, 96d, PixelFormats.Default);
rtb.Render(r);
BmpBitmapEncoder encoder = new BmpBitmapEncoder();
encoder.Frames.Add(BitmapFrame.Create(rtb));
FileStream fs = File.Open(@"C:\lol.png", FileMode.Create);
encoder.Save(fs);
fs.Close();
You could use RenderTargetBitmap class and BitmapEncoder.
Define these methods:
void SaveToBmp(FrameworkElement visual, string fileName)
{
var encoder = new BmpBitmapEncoder();
SaveUsingEncoder(visual, fileName, encoder);
}
void SaveToPng(FrameworkElement visual, string fileName)
{
var encoder = new PngBitmapEncoder();
SaveUsingEncoder(visual, fileName, encoder);
}
// and so on for other encoders (if you want)
void SaveUsingEncoder(FrameworkElement visual, string fileName, BitmapEncoder encoder)
{
RenderTargetBitmap bitmap = new RenderTargetBitmap((int)visual.ActualWidth, (int)visual.ActualHeight, 96, 96, PixelFormats.Pbgra32);
bitmap.Render(visual);
BitmapFrame frame = BitmapFrame.Create(bitmap);
encoder.Frames.Add(frame);
using (var stream = File.Create(fileName))
{
encoder.Save(stream);
}
}
If you have your Image control inside a container like this:
<Grid x:Name="MyGrid">
<Image Name="MyImage" Stretch="None"></Image>
</Grid>
You just need to do so:
SaveToPng(MyGrid, "image.png");
Otherwise you can simply pass the dimensions you want when you use RenderTargetBitmap:
SaveToPng(MyImage, "image.png");
...
RenderTargetBitmap bitmap = new RenderTargetBitmap(YourWidth, YourHeight, 96, 96, PixelFormats.Pbgra32);