Réponses:
Que diriez-vous de le charger à partir de MemoryStream?
using(MemoryStream memory = new MemoryStream())
{
bitmap.Save(memory, ImageFormat.Png);
memory.Position = 0;
BitmapImage bitmapImage = new BitmapImage();
bitmapImage.BeginInit();
bitmapImage.StreamSource = memory;
bitmapImage.CacheOption = BitmapCacheOption.OnLoad;
bitmapImage.EndInit();
}
ms.Seek(0, SeekOrigin.Begin);
avant de régler bi.StreamSource
. J'utilise .NET 4.0.
Merci à Hallgrim, voici le code avec lequel je me suis retrouvé:
ScreenCapture = System.Windows.Interop.Imaging.CreateBitmapSourceFromHBitmap(
bmp.GetHbitmap(),
IntPtr.Zero,
System.Windows.Int32Rect.Empty,
BitmapSizeOptions.FromWidthAndHeight(width, height));
J'ai également fini par me lier à une BitmapSource au lieu d'une BitmapImage comme dans ma question d'origine
DeleteObject
sur ce handle.
BitmapSizeOptions.FromEmptyOptions()
, et cela fonctionne très bien avec ma situation.
Je sais que cela a été répondu, mais voici quelques méthodes d'extension (pour .NET 3.0+) qui effectuent la conversion. :)
/// <summary>
/// Converts a <see cref="System.Drawing.Image"/> into a WPF <see cref="BitmapSource"/>.
/// </summary>
/// <param name="source">The source image.</param>
/// <returns>A BitmapSource</returns>
public static BitmapSource ToBitmapSource(this System.Drawing.Image source)
{
System.Drawing.Bitmap bitmap = new System.Drawing.Bitmap(source);
var bitSrc = bitmap.ToBitmapSource();
bitmap.Dispose();
bitmap = null;
return bitSrc;
}
/// <summary>
/// Converts a <see cref="System.Drawing.Bitmap"/> into a WPF <see cref="BitmapSource"/>.
/// </summary>
/// <remarks>Uses GDI to do the conversion. Hence the call to the marshalled DeleteObject.
/// </remarks>
/// <param name="source">The source bitmap.</param>
/// <returns>A BitmapSource</returns>
public static BitmapSource ToBitmapSource(this System.Drawing.Bitmap source)
{
BitmapSource bitSrc = null;
var hBitmap = source.GetHbitmap();
try
{
bitSrc = System.Windows.Interop.Imaging.CreateBitmapSourceFromHBitmap(
hBitmap,
IntPtr.Zero,
Int32Rect.Empty,
BitmapSizeOptions.FromEmptyOptions());
}
catch (Win32Exception)
{
bitSrc = null;
}
finally
{
NativeMethods.DeleteObject(hBitmap);
}
return bitSrc;
}
et la classe NativeMethods (pour apaiser FxCop)
/// <summary>
/// FxCop requires all Marshalled functions to be in a class called NativeMethods.
/// </summary>
internal static class NativeMethods
{
[DllImport("gdi32.dll")]
[return: MarshalAs(UnmanagedType.Bool)]
internal static extern bool DeleteObject(IntPtr hObject);
}
Il m'a fallu un certain temps pour que la conversion fonctionne dans les deux sens, voici donc les deux méthodes d'extension que j'ai trouvées:
using System.Drawing;
using System.Drawing.Imaging;
using System.IO;
using System.Windows.Media.Imaging;
public static class BitmapConversion {
public static Bitmap ToWinFormsBitmap(this BitmapSource bitmapsource) {
using (MemoryStream stream = new MemoryStream()) {
BitmapEncoder enc = new BmpBitmapEncoder();
enc.Frames.Add(BitmapFrame.Create(bitmapsource));
enc.Save(stream);
using (var tempBitmap = new Bitmap(stream)) {
// According to MSDN, one "must keep the stream open for the lifetime of the Bitmap."
// So we return a copy of the new bitmap, allowing us to dispose both the bitmap and the stream.
return new Bitmap(tempBitmap);
}
}
}
public static BitmapSource ToWpfBitmap(this Bitmap bitmap) {
using (MemoryStream stream = new MemoryStream()) {
bitmap.Save(stream, ImageFormat.Bmp);
stream.Position = 0;
BitmapImage 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;
}
}
}
// at class level;
[System.Runtime.InteropServices.DllImport("gdi32.dll")]
public static extern bool DeleteObject(IntPtr hObject); // https://stackoverflow.com/a/1546121/194717
/// <summary>
/// Converts a <see cref="System.Drawing.Bitmap"/> into a WPF <see cref="BitmapSource"/>.
/// </summary>
/// <remarks>Uses GDI to do the conversion. Hence the call to the marshalled DeleteObject.
/// </remarks>
/// <param name="source">The source bitmap.</param>
/// <returns>A BitmapSource</returns>
public static System.Windows.Media.Imaging.BitmapSource ToBitmapSource(this System.Drawing.Bitmap source)
{
var hBitmap = source.GetHbitmap();
var result = System.Windows.Interop.Imaging.CreateBitmapSourceFromHBitmap(hBitmap, IntPtr.Zero, System.Windows.Int32Rect.Empty, System.Windows.Media.Imaging.BitmapSizeOptions.FromEmptyOptions());
DeleteObject(hBitmap);
return result;
}
Vous pouvez simplement partager les pixeldata entre les deux espaces de noms (Media et Drawing) en écrivant une bitmapsource personnalisée. La conversion se fera immédiatement et aucune mémoire supplémentaire ne sera allouée. Si vous ne souhaitez pas créer explicitement une copie de votre Bitmap, c'est la méthode que vous souhaitez.
class SharedBitmapSource : BitmapSource, IDisposable
{
#region Public Properties
/// <summary>
/// I made it public so u can reuse it and get the best our of both namespaces
/// </summary>
public Bitmap Bitmap { get; private set; }
public override double DpiX { get { return Bitmap.HorizontalResolution; } }
public override double DpiY { get { return Bitmap.VerticalResolution; } }
public override int PixelHeight { get { return Bitmap.Height; } }
public override int PixelWidth { get { return Bitmap.Width; } }
public override System.Windows.Media.PixelFormat Format { get { return ConvertPixelFormat(Bitmap.PixelFormat); } }
public override BitmapPalette Palette { get { return null; } }
#endregion
#region Constructor/Destructor
public SharedBitmapSource(int width, int height,System.Drawing.Imaging.PixelFormat sourceFormat)
:this(new Bitmap(width,height, sourceFormat) ) { }
public SharedBitmapSource(Bitmap bitmap)
{
Bitmap = bitmap;
}
// Use C# destructor syntax for finalization code.
~SharedBitmapSource()
{
// Simply call Dispose(false).
Dispose(false);
}
#endregion
#region Overrides
public override void CopyPixels(Int32Rect sourceRect, Array pixels, int stride, int offset)
{
BitmapData sourceData = Bitmap.LockBits(
new Rectangle(sourceRect.X, sourceRect.Y, sourceRect.Width, sourceRect.Height),
ImageLockMode.ReadOnly,
Bitmap.PixelFormat);
var length = sourceData.Stride * sourceData.Height;
if (pixels is byte[])
{
var bytes = pixels as byte[];
Marshal.Copy(sourceData.Scan0, bytes, 0, length);
}
Bitmap.UnlockBits(sourceData);
}
protected override Freezable CreateInstanceCore()
{
return (Freezable)Activator.CreateInstance(GetType());
}
#endregion
#region Public Methods
public BitmapSource Resize(int newWidth, int newHeight)
{
Image newImage = new Bitmap(newWidth, newHeight);
using (Graphics graphicsHandle = Graphics.FromImage(newImage))
{
graphicsHandle.InterpolationMode = InterpolationMode.HighQualityBicubic;
graphicsHandle.DrawImage(Bitmap, 0, 0, newWidth, newHeight);
}
return new SharedBitmapSource(newImage as Bitmap);
}
public new BitmapSource Clone()
{
return new SharedBitmapSource(new Bitmap(Bitmap));
}
//Implement IDisposable.
public void Dispose()
{
Dispose(true);
GC.SuppressFinalize(this);
}
#endregion
#region Protected/Private Methods
private static System.Windows.Media.PixelFormat ConvertPixelFormat(System.Drawing.Imaging.PixelFormat sourceFormat)
{
switch (sourceFormat)
{
case System.Drawing.Imaging.PixelFormat.Format24bppRgb:
return PixelFormats.Bgr24;
case System.Drawing.Imaging.PixelFormat.Format32bppArgb:
return PixelFormats.Pbgra32;
case System.Drawing.Imaging.PixelFormat.Format32bppRgb:
return PixelFormats.Bgr32;
}
return new System.Windows.Media.PixelFormat();
}
private bool _disposed = false;
protected virtual void Dispose(bool disposing)
{
if (!_disposed)
{
if (disposing)
{
// Free other state (managed objects).
}
// Free your own state (unmanaged objects).
// Set large fields to null.
_disposed = true;
}
}
#endregion
}
Je travaille chez un fournisseur d'imagerie et j'ai écrit un adaptateur pour WPF à notre format d'image qui est similaire à un System.Drawing.Bitmap.
J'ai écrit ce KB pour l'expliquer à nos clients:
http://www.atalasoft.com/kb/article.aspx?id=10156
Et il y a du code qui le fait. Vous devez remplacer AtalaImage par Bitmap et faire la même chose que nous faisons - cela devrait être assez simple.
Mon point de vue sur cette construction à partir d'un certain nombre de ressources. https://stackoverflow.com/a/7035036 https://stackoverflow.com/a/1470182/360211
using System;
using System.Drawing;
using System.Runtime.ConstrainedExecution;
using System.Runtime.InteropServices;
using System.Security;
using System.Windows;
using System.Windows.Interop;
using System.Windows.Media.Imaging;
using Microsoft.Win32.SafeHandles;
namespace WpfHelpers
{
public static class BitmapToBitmapSource
{
public static BitmapSource ToBitmapSource(this Bitmap source)
{
using (var handle = new SafeHBitmapHandle(source))
{
return Imaging.CreateBitmapSourceFromHBitmap(handle.DangerousGetHandle(),
IntPtr.Zero, Int32Rect.Empty,
BitmapSizeOptions.FromEmptyOptions());
}
}
[DllImport("gdi32")]
private static extern int DeleteObject(IntPtr o);
private sealed class SafeHBitmapHandle : SafeHandleZeroOrMinusOneIsInvalid
{
[SecurityCritical]
public SafeHBitmapHandle(Bitmap bitmap)
: base(true)
{
SetHandle(bitmap.GetHbitmap());
}
[ReliabilityContract(Consistency.WillNotCorruptState, Cer.Success)]
protected override bool ReleaseHandle()
{
return DeleteObject(handle) > 0;
}
}
}
}
Je suis venu à cette question parce que j'essayais de faire la même chose, mais dans mon cas, le bitmap provient d'une ressource / d'un fichier. J'ai trouvé que la meilleure solution est celle décrite dans le lien suivant:
http://msdn.microsoft.com/en-us/library/system.windows.media.imaging.bitmapimage.aspx
// Create the image element.
Image simpleImage = new Image();
simpleImage.Width = 200;
simpleImage.Margin = new Thickness(5);
// Create source.
BitmapImage bi = new BitmapImage();
// BitmapImage.UriSource must be in a BeginInit/EndInit block.
bi.BeginInit();
bi.UriSource = new Uri(@"/sampleImages/cherries_larger.jpg",UriKind.RelativeOrAbsolute);
bi.EndInit();
// Set the image source.
simpleImage.Source = bi;