I am reading data from a smartcard.
This data contains a picture as well.
Code to get the picture in a class ReadData:
public Bitmap GetPhotoFile()
{
byte[] photoFile = GetFile("photo_file");
Bitmap photo = new Bitmap(new MemoryStream(photoFile));
return photo;
}
Code in the xaml:
imgphoto = ReadData.GetPhotoFile();
Error being generated:
Cannot implicitly convert type 'System.Drawing.Bitmap' to 'System.Windows.Controls.Image'
What is the best approach in this?
Do not create a System.Drawing.Bitmap from that file. Bitmap is WinForms, not WPF.
Instead, create a WPF BitmapImage
public ImageSource GetPhotoFile()
{
var photoFile = GetFile("photo_file");
var photo = new BitmapImage();
using (var stream = new MemoryStream(photoFile))
{
photo.BeginInit();
photo.CacheOption = BitmapCacheOption.OnLoad;
photo.StreamSource = stream;
photo.EndInit();
}
return photo;
}
Then assign the returned ImageSource to the Source property of the Image control:
imgphoto.Source = ReadData.GetPhotoFile();
Related
I have a view that contains an image control that is binded to this property:
private System.Drawing.Image _sigImage;
public System.Drawing.Image sigImage
{
get { return _sigImage; }
set { _sigImage = value; RaisePropertyChanged(); }
}
I am busy implementing a a signature pad using mvvm, and want the signature to display in the image control. However i cant get it to display.
The code for die signature pad is:
DynamicCapture dc = new DynamicCaptureClass();
DynamicCaptureResult res = dc.Capture(sigCtl, "Who", "Why", null, null);
if (res == DynamicCaptureResult.DynCaptOK)
{
sigObj = (SigObj)sigCtl.Signature;
sigObj.set_ExtraData("AdditionalData", "C# test: Additional data");
try
{
byte[] binaryData = sigObj.RenderBitmap("sign", 200, 150, "image/png", 0.5f, 0xff0000, 0xffffff, 10.0f, 10.0f, RBFlags.RenderOutputBinary | RBFlags.RenderColor32BPP) as byte[];
using (MemoryStream memStream = new MemoryStream(binaryData))
{
System.Drawing.Image newImage = System.Drawing.Image.FromStream(memStream);
sigImage = newImage;
// work with image here.
// You'll need to keep the MemoryStream open for
// as long as you want to work with your new image.
memStream.Dispose();
}
}
catch (Exception ex)
{
MessageBox.Show(ex.Message);
}
}
The image is stored as a bitmap in the variable newImage.
How can i bind that image to the image control of sigImage?
System.Drawing.Image is not an appropriate type for the Source property of an Image element. It is WinForms, not WPF.
Use System.Windows.Media.ImageSource instead
private ImageSource sigImage;
public ImageSource SigImage
{
get { return sigImage; }
set { sigImage = value; RaisePropertyChanged(); }
}
and assign a BitmapImage or BitmapFrame to the property, which is directly created from the MemoryStream. BitmapCacheOption.OnLoad has to be set in order to enable closing the stream immediately after decoding the bitmap.
var bitmapImage = new BitmapImage();
using (var memStream = new MemoryStream(binaryData))
{
bitmapImage.BeginInit();
bitmapImage.CacheOption = BitmapCacheOption.OnLoad;
bitmapImage.StreamSource = memStream;
bitmapImage.EndInit();
}
bitmapImage.Freeze();
SigImage = bitmapImage;
The Binding would look like shown below, provided an instance of the class with the SigImage property is assigned to the DataContext of the view.
<Image Source="{Binding SigImage}"/>
Since WPF has built-in type conversion from string, Uri and byte[] to ImageSource, you may as well declare the source property as byte[]
private byte[] sigImage;
public byte[] SigImage
{
get { return sigImage; }
set { sigImage = value; RaisePropertyChanged(); }
}
and assign a value like
SigImage = binaryData;
without manually creating a BitmapImage or BitmapFrame, or changing the Binding.
I want to read Image file(png, jpg, etc).
and save xml file, load image from xml.
but first. Deserialize throw System.InvalidOperationException.
second. I don't know below method is correct.
Scenario.
1. Open Image file from hdd.
2. Save document(text with image like 'SomeClass' in below source) in my application.
3. When save document, application will serialize SomeClass with image.
4. Rerun application, and load xml file.
5. then, show image in my application.
using (MemoryStream ms = new MemoryStream(File.ReadAllBytes(#"C:\z.jpg")))
{
StreamReader sr = new StreamReader(ms);
someClass.ImageData = sr.ReadToEnd();
Xml.Serialize<SomeClass>(someClass, #"C:\z.xml");
}
SomeClass someClass = Xml.Deserialize<SomeClass>(#"C:\z.xml");
BitmapImage image = new BitmapImage();
image.BegineInit();
image.Source = ??
image.EndInit();
System.Windows.Controls.Image imageControl = new Image();
imageControl.Source = image;
this.Content = imageControl;
this is Serialize, Deserialize static method.
public static class Xml
{
public static void Serialize<T>(T data, string path)
{
XmlSerializer s = new XmlSerializer(typeof(T));
using (FileStream fs = new FileStream(path, FileMode.Create))
{
s.Serialize(fs, data);
}
}
public static T Deserialize<T>(string path)
{
XmlSerializer s = new XmlSerializer(typeof(T));
using (FileStream fs = new FileStream(path, FileMode.Open))
{
fs.Position = 0;
return (T)s.Deserialize(fs);
}
}
}
This is SomeClass
[Serializable]
public class SomeClass
{
public string ImageData { get; set; }
public string TextData { get; set; }
}
thank you.
You need to convert the binary image data to a string. You can use the Convert methods to handle that.
Edit note - Noticed you were reading all bytes into a memory stream and then reading them again from a stream reader. It would simplify the code to just read it directly and convert those bytes to Base64.
Example below.
someClass.ImageData = Convert.ToBase64String(File.ReadAllBytes(#"C:\z.jpg"));
Xml.Serialize<SomeClass>(someClass, #"C:\z.xml");
------------------
SomeClass someClass = Xml.Deserialize<SomeClass>(#"C:\z.xml");
BitmapImage image = new BitmapImage();
image.BegineInit();
image.Source = Convert.FromBase64String(someClass.ImageData);
image.EndInit();
I would like to load Gravatar-Images and set them from code behind to a WPF Image-Control.
So the code looks like
imgGravatar.Source = GetGravatarImage(email);
Where GetGravatarImage looks like:
BitmapImage bi = new BitmapImage();
bi.BeginInit();
bi.UriSource = new Uri( GravatarImage.GetURL( "http://www.gravatar.com/avatar.php?gravatar_id=" + email) , UriKind.Absolute );
bi.EndInit();
return bi;
Unfortunately this locks the GUI when the network connection is slow. Is there a way to assign the image-source and let it load the image in the background without blocking the UI?
Thanks!
I suggest you to use a Binding on your imgGravatar from XAML. Set IsAsync=true on it and WPF will automatically utilize a thread from the thread pool to pull your image. You could encapsulate the resolving logic into an IValueConverter and simply bind the email as Source
in XAML:
<Window.Resouces>
<local:ImgConverter x:Key="imgConverter" />
</Window.Resource>
...
<Image x:Name="imgGravatar"
Source="{Binding Path=Email,
Converter={StaticResource imgConverter},
IsAsync=true}" />
in Code:
public class ImgConverter : IValueConverter
{
public override object Convert(object value, ...)
{
if (value != null)
{
BitmapImage bi = new BitmapImage();
bi.BeginInit();
bi.UriSource = new Uri(
GravatarImage.GetURL(
"http://www.gravatar.com/avatar.php?gravatar_id=" +
value.ToString()) , UriKind.Absolute
);
bi.EndInit();
return bi;
}
else
{
return null;
}
}
}
I can't see why your code would block the UI, as BitmapImage supports downloading image data in the background. That's why it has an IsDownloading property and a DownloadCompleted event.
Anyway, the following code shows a straightforward way to download and create the image entirely in a separate thread (from the ThreadPool). It uses a WebClient instance to download the whole image buffer, before creating a BitmapImage from that buffer. After the BitmapImage is created it calls Freeze to make it accessible from the UI thread. Finally it assigns the Image control's Source property in the UI thread by means of a Dispatcher.BeginInvoke call.
ThreadPool.QueueUserWorkItem(
o =>
{
var url = GravatarImage.GetURL(
"http://www.gravatar.com/avatar.php?gravatar_id=" + email);
var webClient = new WebClient();
var buffer = webClient.DownloadData(url);
var bitmapImage = new BitmapImage();
using (var stream = new MemoryStream(buffer))
{
bitmapImage.BeginInit();
bitmapImage.CacheOption = BitmapCacheOption.OnLoad;
bitmapImage.StreamSource = stream;
bitmapImage.EndInit();
bitmapImage.Freeze();
}
Dispatcher.BeginInvoke((Action)(() => image.Source = bitmapImage));
});
EDIT: today you would just use async methods:
var url = GravatarImage.GetURL(
"http://www.gravatar.com/avatar.php?gravatar_id=" + email);
var httpClient = new HttpClient();
var responseStream = await httpClient.GetStreamAsync(url);
var bitmapImage = new BitmapImage();
using (var memoryStream = new MemoryStream())
{
await responseStream.CopyToAsync(memoryStream);
bitmapImage.BeginInit();
bitmapImage.CacheOption = BitmapCacheOption.OnLoad;
bitmapImage.StreamSource = memoryStream;
bitmapImage.EndInit();
bitmapImage.Freeze();
}
image.Source = bitmapImage;
I need to save the content of a WPF Object as an Image file. In my application I have a chart drawn on a Canvas object. This is what I need to save. The Canvas with all child objects.
What you're looking for is the RenderTargetBitmap class. There's an example of its use on the MSDN page I linked, and there's another good example that includes saving to a file here:
RenderTargetBitmap by Eric Sinc
Here is the func which creates RenderTargetBitmap object, that will be used in further funcs.
public static RenderTargetBitmap ConvertToBitmap(UIElement uiElement, double resolution)
{
var scale = resolution / 96d;
uiElement.Measure(new Size(Double.PositiveInfinity, Double.PositiveInfinity));
var sz = uiElement.DesiredSize;
var rect = new Rect(sz);
uiElement.Arrange(rect);
var bmp = new RenderTargetBitmap((int)(scale * (rect.Width)), (int)(scale * (rect.Height)), scale * 96, scale * 96, PixelFormats.Default);
bmp.Render(uiElement);
return bmp;
}
This functionc creates JPEG string content of file and writes it to a file:
public static void ConvertToJpeg(UIElement uiElement, string path, double resolution)
{
var jpegString = CreateJpeg(ConvertToBitmap(uiElement, resolution));
if (path != null)
{
try
{
using (var fileStream = File.Create(path))
{
using (var streamWriter = new StreamWriter(fileStream, Encoding.Default))
{
streamWriter.Write(jpegString);
streamWriter.Close();
}
fileStream.Close();
}
}
catch (Exception ex)
{
//TODO: handle exception here
}
}
}
This function used above to create JPEG string representation of Image content:
public static string CreateJpeg(RenderTargetBitmap bitmap)
{
var jpeg = new JpegBitmapEncoder();
jpeg.Frames.Add(BitmapFrame.Create(bitmap));
string result;
using (var memoryStream = new MemoryStream())
{
jpeg.Save(memoryStream);
memoryStream.Seek(0, SeekOrigin.Begin);
using (var streamReader = new StreamReader(memoryStream, Encoding.Default))
{
result = streamReader.ReadToEnd();
streamReader.Close();
}
memoryStream.Close();
}
return result;
}
Hope this helps.
With the help of the Eric Sinc tutorial I came to the following solution:
It uses a win32 SaveDialog to choose where the file should go and a PngBitmapEncoder (many other BitmapEncoders available!) to convert it to something we can save.
Note that the element being saved in this example is "cnvClasses" and that the size of the output is, quite deliberately, the same as the control.
SaveFileDialog svDlg = new SaveFileDialog();
svDlg.Filter = "PNG files|*.png|All Files|*.*";
svDlg.Title = "Save diagram as PNG";
if (svDlg.ShowDialog().Value == true)
{
RenderTargetBitmap render = new RenderTargetBitmap((int)this.cnvClasses.ActualWidth, (int)this.cnvClasses.ActualHeight, 96, 96, PixelFormats.Pbgra32);
render.Render(cnvClasses);
PngBitmapEncoder encoder = new PngBitmapEncoder();
encoder.Frames.Add(BitmapFrame.Create(render));
using (FileStream fs = new FileStream(svDlg.FileName, FileMode.Create))
encoder.Save(fs);
}
In an app I need to serialize an image through a binarywriter, and to get it in an other app to display it.
Here is a part of my "serialization" code :
FileStream fs = new FileStream(file, FileMode.Create, FileAccess.Write);
BinaryWriter bin = new BinaryWriter(fs);
bin.Write((short)this.Animations.Count);
for (int i = 0; i < this.Animations.Count; i++)
{
MemoryStream stream = new MemoryStream();
BitmapEncoder encoder = new PngBitmapEncoder();
encoder.Frames.Add(BitmapFrame.Create(Animations[i].Image));
encoder.Save(stream);
stream.Seek(0, SeekOrigin.Begin);
bin.Write((int)stream.GetBuffer().Length);
bin.Write(stream.GetBuffer());
stream.Close();
}
bin.Close();
And here is the part of my deserialization that load the image :
FileStream fs = new FileStream(fileName, FileMode.Open, FileAccess.Read);
BinaryReader bin = new BinaryReader(fs);
int animCount = bin.ReadInt16();
int imageBytesLenght;
byte[] imageBytes;
BitmapSource img;
for (int i = 0; i < animCount; i++)
{
imageBytesLenght = bin.ReadInt32();
imageBytes = bin.ReadBytes(imageBytesLenght);
img = new BitmapImage();
MemoryStream stream = new MemoryStream(imageBytes);
BitmapDecoder dec = new PngBitmapDecoder(stream, BitmapCreateOptions.PreservePixelFormat, BitmapCacheOption.Default);
img = dec.Frames[0];
stream.Close();
}
bin.Close();
When I use this method, I load the image (it seems to be stored in the "img" object) but it can't be displayed.
Has somedy an idea?
Thanks
KiTe
UPD :
I already do this : updating my binding, or even trying to affect it directly through the window code behing. None of these approaches work :s
However, when I add this :
private void CreateFile(byte[] bytes)
{
FileStream fs = new FileStream(Environment.CurrentDirectory + "/" + "testeuh.png", FileMode.Create, FileAccess.Write);
fs.Write(bytes, 0, bytes.Length);
fs.Close();
}
at the end of you function, it perfectly create the file, which can be read without any problems ... So I don't know where the problem can be.
UPD 2 :
A weird things happens.
Here is the binding I use :
<Image x:Name="imgSelectedAnim" Width="150" Height="150" Source="{Binding ElementName=lstAnims, Path=SelectedItem.Image}" Stretch="Uniform" />
(the list is itself binded on an observableCollection).
When I create manually the animation through the app, it works (the image is displayed).
But when I load it, it is not displayed (I look at my code, there are not any "new" which could break up my binding, since there are others properties binded the same way and they does not fail).
Moreover, I've put a breakpoint on the getter/setter of the properties Image of my animation.
When it is created, no problems, it has the good informations.
But when it is retreived through the getter, it return a good image the first time, and then and image with pixelWidth, pixelHeight, width, height of only 1 but without going through the setter anymore !
Any idea?
UPD3
tried what you said like this :
Added a property TEST in my viewModel :
private BitmapSource test;
public BitmapSource TEST { get { return test; } set { test = value; RaisePropertyChanged("TEST"); } }
then did it :
img = getBmpSrcFromBytes(bin.ReadBytes(imageBytesLenght));
TEST = img;
(in the code showed and modified before)
and my binding :
<Image x:Name="imgSelectedAnim" Width="150" Height="150" Source="{Binding Path=TEST}" Stretch="Uniform" />
(datacontext is set to my ViewModel)
And it still doesn't work and does the weird image modification (pixW, pixH, W and H set to 1)
FINAL UPD:
It seems I finally solved the problem. Here is simply what I did :
byte[] bytes = bin.ReadBytes(imageBytesLenght);
MemoryStream mem = new MemoryStream(bytes);
img = new BitmapImage();
img.BeginInit();
img.StreamSource = mem;
img.EndInit();
the strange thing is that it didn't work the first time, maybe it is due to an architectural modification within my spriteanimation class, but I don't think it is.
Well, thank you a lot to Eugene Cheverda for his help
At the first, I think you should store your images in a list of BitmapSource and provide reverse encoding of image for using stream as BitmapImage.StreamSource:
FileStream fs = new FileStream(fileName, FileMode.Open, FileAccess.Read);
BinaryReader bin = new BinaryReader(fs);
int animCount = bin.ReadInt16();
int imageBytesLenght;
byte[] imageBytes;
List<BitmapSource> bitmaps = new List<BitmapSource>();
for (int i = 0; i < animCount; i++)
{
imageBytesLenght = bin.ReadInt32();
imageBytes = bin.ReadBytes(imageBytesLenght);
bitmaps.Add(getBmpSrcFromBytes(imageBytes));
}
bin.Close();
UPD
In code above use func written below:
private BitmapSource getBmpSrcFromBytes(byte[] bytes)
{
using (var srcStream = new MemoryStream(bytes))
{
var dec = new PngBitmapDecoder(srcStream, BitmapCreateOptions.PreservePixelFormat,
BitmapCacheOption.Default);
var encoder = new PngBitmapEncoder();
encoder.Frames.Add(dec.Frames[0]);
BitmapImage bitmapImage = null;
bool isCreated;
try
{
using (var ms = new MemoryStream())
{
encoder.Save(ms);
bitmapImage = new BitmapImage();
bitmapImage.BeginInit();
bitmapImage.StreamSource = ms;
bitmapImage.EndInit();
isCreated = true;
}
}
catch
{
isCreated = false;
}
return isCreated ? bitmapImage : null;
}
}
Hope this helps.
UPD #2
Your binding is incorrect. You may be should bind selected item to for example CurrentImageSource. And then this CurrentImageSource bind to Image control.
Code:
public class MyViewModel : INotifyPropertyChanged
{
public ObservableCollection<BitmapSource> ImagesCollection { get; set; }
private BitmapSource _currentImage;
public BitmapSource CurrentImage
{
get { return _currentImage; }
set
{
_currentImage = value;
raiseOnPropertyChanged("CurrentImage");
}
}
private void raiseOnPropertyChanged(string propertyName)
{
if (PropertyChanged != null)
PropertyChanged(this, new PropertyChangedEventArgs(propertyName));
}
public event PropertyChangedEventHandler PropertyChanged;
}
Then:
<ListBox ItemsSource="{Binding ImagesCollection}" SelectedItem="{Binding CurrentImage}"/>
<Image Source="{Binding CurrentImage}"/>
ADDED
Here is the sample project in which implemented technique as I described above.
It creates animations collection and represent them in listbox, selected animation is displayed in Image control using its Image property.
What I want to say is that if you cannot obtain image as it should be, you need to search problems in serialization/deserialization.