This can be solved through an extension method:
using System.Drawing;
using System.Drawing.Imaging;
using System.IO;
using System.Windows.Media.Imaging;
/// <remarks>
/// Requires reference to <c>System.Drawing</c>, <c>PresentationCore</c> and <c>WindowsBase</c>.
/// </remarks>
public static class JpegXr {
public static MemoryStream SaveJpegXr(this Bitmap bitmap, float quality) {
var stream = new MemoryStream();
SaveJpegXr(bitmap, quality, stream);
stream.Seek(0, SeekOrigin.Begin);
return stream;
}
public static void SaveJpegXr(this Bitmap bitmap, float quality, Stream output) {
var bitmapSource = bitmap.ToWpfBitmap();
var bitmapFrame = BitmapFrame.Create(bitmapSource);
var jpegXrEncoder = new WmpBitmapEncoder();
jpegXrEncoder.Frames.Add(bitmapFrame);
jpegXrEncoder.ImageQualityLevel = quality / 100f;
jpegXrEncoder.Save(output);
}
/// <seealso cref="http://stackoverflow.com/questions/94456/load-a-wpf-bitmapimage-from-a-system-drawing-bitmap"/>
public static BitmapSource ToWpfBitmap(this Bitmap bitmap) {
using (var stream = new MemoryStream()) {
bitmap.Save(stream, ImageFormat.Bmp);
stream.Position = 0;
var result = new BitmapImage();
result.BeginInit();
// According to MSDN, "The default OnDemand cache option retains access to the stream until the image is needed."
// Force the bitmap to load right now so we can dispose the stream.
result.CacheOption = BitmapCacheOption.OnLoad;
result.StreamSource = stream;
result.EndInit();
result.Freeze();
return result;
}
}
}
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