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Image does not update after using File.Copy with the same filename [duplicate]

I have a WPF application that takes a snapshot image from a video file. The user can define the timestamp from which to take the image. The image is then saved to a temporary location on disk, and is then rendered into an <image> element.
The user should then be able to select a different timestamp, which then overwrites the temporary file on disk - this should then be displayed within the <image> element.
Using Image.Source = null;, I can clear the image file from the <image> element, so it displays a blank space instead. However, if the source image file is then overwritten with a new image (with the same name) and loaded into the <image> element, it still shows the old image.
I am using the following logic:
// Overwrite temporary file file here
// Clear out the reference to the temporary image
Image_Preview.Source = null;
// Load in new image (same source file name)
Image = new BitmapImage();
Image.BeginInit();
Image.CacheOption = BitmapCacheOption.OnLoad;
Image.UriSource = new Uri(file);
Image.EndInit();
Image_Preview.Source = Image;
The image displayed in the <image> element does not change, even though the original file has been completely replaced. Is there an image caching issue here that I am not aware of?

By default, WPF caches BitmapImages that are loaded from URIs.
You can avoid that by setting the BitmapCreateOptions.IgnoreImageCache flag:
var image = new BitmapImage();
image.BeginInit();
image.CreateOptions = BitmapCreateOptions.IgnoreImageCache;
image.CacheOption = BitmapCacheOption.OnLoad;
image.UriSource = new Uri(file);
image.EndInit();
Image_Preview.Source = image;
Or you load the BitmapImage directly from a Stream:
var image = new BitmapImage();
using (var stream = new FileStream(file, FileMode.Open, FileAccess.Read))
{
image.BeginInit();
image.CacheOption = BitmapCacheOption.OnLoad;
image.StreamSource = stream;
image.EndInit();
}
Image_Preview.Source = image;

WPF - refresh image source after replacing image [duplicate]

I have a WPF application that takes a snapshot image from a video file. The user can define the timestamp from which to take the image. The image is then saved to a temporary location on disk, and is then rendered into an <image> element.
The user should then be able to select a different timestamp, which then overwrites the temporary file on disk - this should then be displayed within the <image> element.
Using Image.Source = null;, I can clear the image file from the <image> element, so it displays a blank space instead. However, if the source image file is then overwritten with a new image (with the same name) and loaded into the <image> element, it still shows the old image.
I am using the following logic:
// Overwrite temporary file file here
// Clear out the reference to the temporary image
Image_Preview.Source = null;
// Load in new image (same source file name)
Image = new BitmapImage();
Image.BeginInit();
Image.CacheOption = BitmapCacheOption.OnLoad;
Image.UriSource = new Uri(file);
Image.EndInit();
Image_Preview.Source = Image;
The image displayed in the <image> element does not change, even though the original file has been completely replaced. Is there an image caching issue here that I am not aware of?

By default, WPF caches BitmapImages that are loaded from URIs.
You can avoid that by setting the BitmapCreateOptions.IgnoreImageCache flag:
var image = new BitmapImage();
image.BeginInit();
image.CreateOptions = BitmapCreateOptions.IgnoreImageCache;
image.CacheOption = BitmapCacheOption.OnLoad;
image.UriSource = new Uri(file);
image.EndInit();
Image_Preview.Source = image;
Or you load the BitmapImage directly from a Stream:
var image = new BitmapImage();
using (var stream = new FileStream(file, FileMode.Open, FileAccess.Read))
{
image.BeginInit();
image.CacheOption = BitmapCacheOption.OnLoad;
image.StreamSource = stream;
image.EndInit();
}
Image_Preview.Source = image;

Saving an captured image to the local folder

I am taking pictures and would like to save them according to the time they were exactly taken.
I would also like to create a folder named /pictures in the current directory and save the pictures in that folder. This is done in C# & WPF.
This is my code:
Image newimage = new Image();
BitmapImage myBitmapImage = new BitmapImage();
myBitmapImage.BeginInit();
newimage.Source = Capture(true) // Take picture
myBitmapImage.UriSource = new Uri(#"c:\" +
string.Format("{0:yyyy-MM-dd_hh-mm-ss-tt}", DateTime.Now) + ".jpg");
// Gives error: Could not find file 'c:\2013-05-26_04-40-25-AM.jpg'
myBitmapImage.EndInit();
newimage.Source = myBitmapImage;
newstackPanel.Children.Add(newimage);
Results in:
ERROR Could not find file 'c:\2013-05-26_04-44-59-AM.jpg'.
Why is it trying to find a file VS just saving the file on the c:\ drive?

If all you want to do is to save the image to disk, then you should use the BitmapEncoder class
JpegBitmapEncoder encoder = new JpegBitmapEncoder();
var image = Capture(true); // Take picture
encoder.Frames.Add(BitmapFrame.Create(image));
// Save the file to disk
var filename = String.Format("...");
using (var stream = new FileStream(filename, FileMode.Create))
{
encoder.Save(stream);
}
The above example creates a JPEG image, but you any encoder you want - WFP comes with Png, Tiff, Gif, Bmp and Wmp encoders built in.

What is to FromFile and ToFile equivalent for BitmapImage?

The System.Drawing.Image has the easy to use methods for FromFile and ToFile. What is the equivalent for the Silverlight BitmapImage? I am trying to load and save a jpeg image as part of a unit test. The bytes must match exactly for it to pass. Here is my current guess:
//I am not sure this is right
private BitmapImage GetImage(string fileName)
{
BitmapImage bitmapImage = new System.Windows.Media.Imaging.BitmapImage();
using (Stream imageStreamSource = new FileStream(fileName, FileMode.Open, FileAccess.Read, FileShare.Read))
{
bitmapImage.BeginInit();
bitmapImage.StreamSource = imageStreamSource;
bitmapImage.EndInit();
}
return bitmapImage;
}
private void SaveImage(BitmapImage bitmapImage, string file)
{
//How to do this?
}

An in-browser Silverlight application cannot open a file using a filename. You would need it run out-of-browser with elevated trust to do that.
Silverlight has no built-in image encoding so you can't take the contents of a bitmap (BTW you would need to be using WriteableBitmap to be able to access the raw image).
You find something you need in Image Tools.

From MSDN link, use the ctor overload which takes in a URI or
BitmapImage myBitmapImage = new BitmapImage();
// BitmapImage.UriSource must be in a BeginInit/EndInit block
myBitmapImage.BeginInit();
myBitmapImage.UriSource = new Uri(#"C:\Documents and Settings\All Users\Documents\My Pictures\Sample Pictures\Water Lilies.jpg");
myBitmapImage.DecodePixelWidth = 200;
myBitmapImage.EndInit();
//set image source
myImage.Source = myBitmapImage;
To save the image to disk, you'd need the specific encoder e.g. JpegBitmapEncoder

Load a BitmapSource and save using the same name in WPF -> IOException

When I try to save a BitmapSource that I loaded earlier, a System.IO.IOException is thrown stating another process is accessing that file and the filestream cannot be opened.
If I only save whithout loading earlier, everything works fine.
The loading code:
BitmapImage image = new BitmapImage();
image.BeginInit();
image.UriSource = uri;
if (decodePixelWidth > 0)
image.DecodePixelWidth = decodePixelWidth;
image.EndInit();
the saving code:
using (FileStream fileStream = new FileStream(Directory + "\\" + FileName + ".jpg", FileMode.Create))
{
JpegBitmapEncoder encoder = new JpegBitmapEncoder();
encoder.Frames.Add(BitmapFrame.Create((BitmapImage)image));
encoder.QualityLevel = 100;
encoder.Save(fileStream);
}
It seems like after loading the image data, the file is still locked an can never be overwritten while the application who opened it is still running. Any ideas how to solve this? Thanks alot for any solutions.

Inspired by the comments I got on this issue, I solved the problem by reading all bytes into a memorystream and using it as the BitmapImage's Sreamsource.
This one works perfectly:
if (File.Exists(filePath))
{
MemoryStream memoryStream = new MemoryStream();
byte[] fileBytes = File.ReadAllBytes(filePath);
memoryStream.Write(fileBytes, 0, fileBytes.Length);
memoryStream.Position = 0;
image.BeginInit();
image.StreamSource = memoryStream;
if (decodePixelWidth > 0)
image.DecodePixelWidth = decodePixelWidth;
image.EndInit();
}

Here is another solution, based upon the original loading code:
var image = new BitmapImage();
image.BeginInit();
// overwrite cache if already exists, to refresh image
image.CreateOptions = BitmapCreateOptions.IgnoreImageCache;
// load into memory and unlock file
image.CacheOption = BitmapCacheOption.OnLoad;
image.UriSource = uri;
if (decodePixelWidth > 0) image.DecodePixelWidth = decodePixelWidth;
image.EndInit();

Add the following line to your loading code:
image.CacheOption = BitmapCacheOption.OnLoad;
This will load open the file, read it into memory, and close it all during image.EndInit. The default of BitmapCacheOption.Default has the odd behavior of opening the file, reading it into memory, but not yet closing it during image.EndInit.

Now i'm not sure if this can be applied to BitmapImage but i had a very similar problem with saving a modified image to the original file in GDI+ here
The method of loading the image from file keeps a lock open on the file until the image object is disposed.
Maybe it's the same thing with bitmapimage.urisource. Without playing around could you copy the image in memory and dispose the original thus unlocking the file?

Setting CacheOption to BitmapCacheOption.OnLoad, will not solve your problem. I think there is a bug, but I had the same problem. Finally i loaded my image to a memory stream and disposed the BitmapImage before saving the image to the file.