Update image file from parallel Task issue - c#

I use this code to populate WPF Image Control.
string pathToImage = System.IO.Path.Combine(Settings.ContentFolderPath, file);
Image image = new Image();
BitmapImage src = new BitmapImage();
src.BeginInit();
src.UriSource = new Uri(pathToImage, UriKind.Absolute);
src.EndInit();
double ratio = src.Width / src.Height;
image.Source = src;
image.Stretch = Stretch.Uniform;
image.Height = marquee1.Height;
image.Width = marquee1.Height * ratio;
lstItems.Items.Add(image);
Also I have some parallel Task to update this image file.
But when I try to delete it I am getting the error: File is busy by other process you cannot delete this file.
How to resolve this issue?
Thank you!
UPDATES
So thank you all of you!
The final solution needs to implement
src.CacheOption = BitmapCacheOption.OnLoad;
src.CreateOptions = BitmapCreateOptions.IgnoreImageCache;
the working code looks like
Image image = new Image();
BitmapImage src = new BitmapImage();
src.BeginInit();
src.CacheOption = BitmapCacheOption.OnLoad;
src.CreateOptions = BitmapCreateOptions.IgnoreImageCache;
src.UriSource = new Uri(pathToImage, UriKind.Absolute);
src.EndInit();
double ratio = src.Width / src.Height;
image.Source = src;
image.Stretch = Stretch.Uniform;
image.Height = marquee1.Height;
image.Width = marquee1.Height * ratio;
lstItems.Items.Add(image);
result = image.Width;

MSND BitmapImage.CacheOption says:
Set the CacheOption to BitmapCacheOption.OnLoad if you wish to close a
stream used to create the BitmapImage.
Set the BitmapImage.CacheOption to OnLoad:
BitmapImage src = new BitmapImage();
src.BeginInit();
src.UriSource = new Uri(pathToImage, UriKind.Absolute);
src.CacheOption = BitmapCacheOption.OnLoad;
src.EndInit();

Set the CacheOption property of the BitmapImage to BitmapCacheOption.OnLoad. This will cause it to load the image into memory and close the original file, which should allow you to delete it.

Also I have some parallel Task to update this image file ... when I try to delete it I am getting the error
In general, you can't delete a Windows file while a process is using it. The consumer Windows FAQs include this page to describe this restriction. And as MSDN describes, File.Delete will refuse to delete a file that's in use.

Related

BitmapImage -> Bitmap -> Mat -> Bitmap ->BitmapImage Convert

I'm developing a kind of real-time video chatting and also trying to make a binary image using OpenCV. I'm working on C# WPF and I have to draw images on Canvas. This means I need 'BitmapImage' to draw the screen. But I have to use 'Mat' to make a binary image.
So I tried many solutions found from StackOverflow but never worked for me.
Below is my code.
Mat tempMat = new Mat();
Bitmap tempImage = BitmapImage2Bitmap(tempOriginal);
tempMat = BitmapConverter.ToMat(tempImage);
Converting BitmapImage to Bitmap first, and then convert Bitmap to Mat.
After that, make image binary. Below is the code.
Mat hsv = new Mat();
Mat binary = new Mat();
Cv2.CvtColor(tempMat, hsv, ColorConversionCodes.BGR2HSV);
Cv2.InRange(hsv, new Scalar(minH, minS, minV), new Scalar(maxH, maxS, maxV), binary);
tempMat = binary.Clone();
binary.Release();
hsv.Release();
After this operation, convert the mat back to Bitmap and BitmapImage again.
Below is the code.
tempImage = BitmapConverter.ToBitmap(tempMat);
BitmapImage resultBitmap = Bitmap2BitmapImage(tempImage);
ipWindow.ipView.ImageSource = resultBitmap;
I searched a lot and tried several solutions to change Bitmap to BitmapImage and vice versa.
But never worked. Below codes are solutions I tried.
I'm new to C# and also WPF, so I have no idea how to solve this problem.
Thanks for reading this long question.
Solution1. BitmapImage -> Bitmap
private Bitmap BitmapImage2Bitmap(BitmapImage bitmapImage){
using (MemoryStream outStream = new MemoryStream())
{
BitmapEncoder enc = new BmpBitmapEncoder();
enc.Frames.Add(BitmapFrame.Create(bitmapImage));
enc.Save(outStream);
Bitmap bitmap = new Bitmap(outStream);
outStream.Close();
return new Bitmap(bitmap);
}
}
Solution1. Bitmap -> BitmapImage
private BitmapImage Bitmap2BitmapImage(Bitmap bitmap){
BitmapSource i = Imaging.CreateBitmapSourceFromHBitmap(
bitmap.GetHbitmap(),
IntPtr.Zero,
Int32Rect.Empty,
BitmapSizeOptions.FromEmptyOptions());
return (BitmapImage)i;
}
Solution2. Bitmap -> BitmapImage
private BitmapImage Bitmap2BitmapImage(Bitmap inputBitmap){
Bitmap bitmap = new Bitmap(inputBitmap.Width, inputBitmap.Height, System.Drawing.Imaging.PixelFormat.Format32bppArgb);
MemoryStream ms = new MemoryStream();
bitmap.Save(ms, ImageFormat.Bmp);
var bi = new BitmapImage();
bi.BeginInit();
bi.StreamSource = ms;
bi.CacheOption = BitmapCacheOption.OnLoad;
bi.EndInit();
return bi;
}
Solution3. Bitmap -> BitmapImage
private BitmapImage Bitmap2BitmapImage(Bitmap inputBitmap){
using (var memory = new MemoryStream())
{
inputBitmap.Save(memory, ImageFormat.Png);
memory.Position = 0;
BitmapImage bitmapImage = new BitmapImage();
bitmapImage.BeginInit();
bitmapImage.StreamSource = memory;
bitmapImage.CacheOption = BitmapCacheOption.OnLoad;
bitmapImage.EndInit();
bitmapImage.Freeze();
return bitmapImage;
}
Solution4. Bitmap -> BitmapImage
private BitmapImage Bitmap2BitmapImage(Bitmap inputBitmap){
MemoryStream ms = new MemoryStream();
inputBitmap.Save(ms, ImageFormat.Bmp);
BitmapImage image = new BitmapImage();
image.BeginInit();
ms.Seek(0, SeekOrigin.Begin);
image.StreamSource = ms;
image.EndInit();
return image;
}
I solved. The problems were two.
One was OpenCvSharp and another was Bitmap to BitmapImage.
Actually OpenCvSharp problem was severe so I couldn't find proper solutions between above. But after I uninstall and reinstall the openCvSharp, I found out what solution works for me. The code is below.
private BitmapImage Bitmap2BitmapImage(Bitmap inputBitmap)
{
using (var memory = new MemoryStream())
{
inputBitmap.Save(memory, ImageFormat.Png);
memory.Position = 0;
BitmapImage bitmapImage = new BitmapImage();
bitmapImage.BeginInit();
bitmapImage.StreamSource = memory;
bitmapImage.CacheOption = BitmapCacheOption.OnLoad;
bitmapImage.EndInit();
bitmapImage.Freeze();
return bitmapImage;
}
}

How to change foreground color for SVG images in WPF and c#

We are trying to get bitmap from SVG but its not giving the exact co-ordinate to change the pixel color.Can anyone help me how to change the color for bitmap pixel/svg pixel in wpf.
WpfDrawingSettings wpfDrawingSettings = new WpfDrawingSettings { IncludeRuntime = false, TextAsGeometry = false, OptimizePath = true };
StreamSvgConverter converter = new StreamSvgConverter(wpfDrawingSettings);
MemoryStream ms = new MemoryStream();
converter.Convert(str, ms);
BitmapImage bitmap = new BitmapImage();
bitmap.BeginInit();
bitmap.StreamSource = ms;
bitmap.CacheOption = BitmapCacheOption.OnLoad;
bitmap.EndInit();

Invalid URI escaping (.Net 4.5)

I have follow C# code (.Net 4.5)
var bi = new BitmapImage();
bi.BeginInit();
bi.DecodePixelWidth = 64;
bi.CacheOption = BitmapCacheOption.OnLoad;
bi.UriSource = new Uri(_filename);
bi.EndInit();
bi.Freeze();
return bi;
At the opening Local file
C:\Users\KVV\Desktop\1111111111111\Windows%20XP6.jpg
Сatch exception
System.IO.FileNotFoundException
with FileName = C:\Users\KVV\Desktop\1111111111111\Windows XP6.jpg
%20 was replaced space
How can I create working URL for such files (need only local files).
Or may be can create BitmapImage without create url for local file.
Problem may be resolve with FileStream.
using (var stream = System.IO.File.OpenRead(s))
{
var img1 = new BitmapImage();
img1.BeginInit();
img1.CacheOption = BitmapCacheOption.OnLoad;
img1.StreamSource = stream;
img1.EndInit();
im1.Source = img1;
}
But this behavior Uri is similar to bug.

Update BitmapImage every second flickers

I am trying to update an image by setting the source property every second, this works however causes a flicker when updated.
CurrentAlbumArt = new BitmapImage();
CurrentAlbumArt.BeginInit();
CurrentAlbumArt.UriSource = new Uri((currentDevice as AUDIO).AlbumArt);
CurrentAlbumArt.CreateOptions = BitmapCreateOptions.IgnoreImageCache;
CurrentAlbumArt.EndInit();
If I don't set IgnoreImageCache, the image does not update thus no flickering either.
Is there a way around this caveat?
Cheers.
The following code snippet downloads the whole image buffer before setting the Image's Source property to a new BitmapImage. This should eliminate any flicker.
var webClient = new WebClient();
var url = ((currentDevice as AUDIO).AlbumArt;
var bitmap = new BitmapImage();
using (var stream = new MemoryStream(webClient.DownloadData(url)))
{
bitmap.BeginInit();
bitmap.CacheOption = BitmapCacheOption.OnLoad;
bitmap.StreamSource = stream;
bitmap.EndInit();
}
image.Source = bitmap;
If the download takes some time, it would make sense to run it in a separate thread. You would then have to take care for proper cross-thread access by also calling Freeze on the BitmapImage and assigning Source in the Dispatcher.
var bitmap = new BitmapImage();
using (var stream = new MemoryStream(webClient.DownloadData(url)))
{
bitmap.BeginInit();
bitmap.CacheOption = BitmapCacheOption.OnLoad;
bitmap.StreamSource = stream;
bitmap.EndInit();
}
bitmap.Freeze();
image.Dispatcher.Invoke((Action)(() => image.Source = bitmap));

WPF Add a png image from resources with C# at runtime

I'm trying to add an image in a stack panel at runtime. My image is in the resources of the application. Here's the code that I have for the moment:
Image image = new Image();
ImageSourceConverter isc = new ImageSourceConverter();
image.Source = isc.ConvertFrom(Properties.Resources.entity16_10) as ImageSource;
image.Height = 16;
image.Width = 16;
panel.Children.Add(image);
I've got a null pointer on the line where I'm trying to use the converter, I don't know if it's the good way of doing this.
Here's how i do it :
object imguri = new Uri("/MyAssembly;Component/MyImageFolder/MyImage.png", UriKind.Relative);
BitmapImage ni = new BitmapImage(imguri);
Image img = new Image();
img.Source = ni;
return img;

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