how can crop image using c# windows phone
crop rect from image
how can crop face from image
the code :
BitmapImage bmp = new BitmapImage();
bmp.SetSource(e.ChosenPhoto);
imgShow.ImageSource = bmp;
var wb = new WriteableBitmap(bmp);
var sdkImg = ImageConverter.SystemToSdk(wb);
IFaceDetector detector = FaceDetectorFactory.Create(FaceDetectionType.Haar);
var gray = new ImageGray(sdkImg);
FaceRect[] rc = detector.Detect(gray);
MessageBox.Show(rc[0].ToString());
faceRect.Margin = new Thickness(rc[1].Rect.Left / 2, rc[1].Rect.Top / 2, 0, 0);
faceRect.Width = rc[1].Rect.Width;
faceRect.Height = rc[1].Rect.Height;
faceRect.Visibility = System.Windows.Visibility.Visible;
You could simply do it using the WriteableBitmap class which is inherited from BitmapSource. There are many samples out there, which you could follow.
References:
WindowsPhone: Image crop with rectangle
Crop Image Area with Different Shapes
Crop an Image using the WriteableBitmap
Related
I'm new with Xamarin. I'm actually trying to set the background image of a view and stretch it.
The image is a 2048x1536 pixels png.
nfloat vpHeight = View.Bounds.Height;
nfloat vpWidth = View.Bounds.Width;
Console.WriteLine(vpWidth);
Console.WriteLine(vpHeight);
The above code will return me 1024x768 (it's a landscape position).
var img = UIImage.FromFile("pages/p1.png");
UIImageView imgView = new UIImageView(img);
imgView.ContentMode = UIViewContentMode.ScaleAspectFit;
var prevPage = new UIView()
{
Frame = new CoreGraphics.CGRect(0, 0, vpWidth, vpHeight)
};
prevPage.Add(imgView);
this is the code where I set the background, but the result is just the half of the image in x and y just like the image bellow:
So, how to make the image to adjust to the width and height of the view ?
ty !!
I would create an UIImageView as a background like so:
var img = UIImage.FromFile("pages/p1.png");
UIImageView imgView = new UIImageView(img);
imgView.ContentMode = UIViewContentMode.ScaleAspectFit;
then add this to whatever view you are using.
ContentMode can be used like so:
Update
I would add it to the prevPage like so:
var prevPage = new UIView()
{
Frame = new CoreGraphics.CGRect(0, 0, vpWidth, vpHeight)
};
var img = UIImage.FromFile("pages/p1.png");
UIImageView imgView = new UIImageView(new CGRect(0,0,vpWidth,vpHeight));
imgView.Image = img;
imgView.ContentMode = UIViewContentMode.ScaleAspectFit; // or ScaleAspectFill
prevPage.Add(imgView);
Also its worth noting that using the View.Bounds to position the view is bit clunky. I would take a look into Autolayout as you will encounter problems on different devices and orientations. These are some good tutorials on Autolayout they might be native code but you are looking for the relationships of the views rather than the code.
Raywenderlich tutorial
Other Tutorial
Any probs with autolayout just ask another question.
I would recommend you stay away from FromPatternImage unless you are really using a pattern.
For the lowest memory consumption and best UI performance, this is what I do:
1st) Resize your image using an image context to match the size of the view:
UIGraphics.BeginImageContext(View.Frame.Size);
UIImage.FromBundle("bg.jpg").Draw(View.Bounds);
var bgImage = UIGraphics.GetImageFromCurrentImageContext();
UIGraphics.EndImageContext();
2nd) Display the resized image in a UIImageView and send it to the lowest Z-order:
var uiImageView = new UIImageView(View.Frame);
uiImageView.Image = bgImage;
View.AddSubview(uiImageView);
View.SendSubviewToBack(uiImageView);
I finish from resizing image but how can I change Background Color (Change black Color)?
Like this image:
http://i.stack.imgur.com/2Y3xG.jpg
BitmapImage img = new BitmapImage();
img.SetSource(e.ChosenPhoto);
Image image2 = new Image()
{
Width=640,Height=640,Visibility=Visibility.Collapsed,Source=img
};
WriteableBitmap wb1 = new WriteableBitmap(image2,st);
wb1.SaveJpeg(ms1, 640, 640, 0, 100);
you must place your Image control inside a container control (like a grid) and change the background color of that container.
I want to merge two images,one image is of 300x300 and other is 100x100, First i have created a canvas and then i created two images which i have added to the both the images to canvas and the canvas is added to the content panel, then i created a writeablebitmap and render the canvas and created a method savejpeg which saves the image to isolated stoarage,but isolated storage is not showing the whole image it save a black screen.
First i created a canvas through code set its height width and background color then i created two images programmatically which i have added to the canvas and then canvas is added to the contentpanel
my code is:
public void CreateImage()
{
Canvas canvas = new Canvas();
canvas.Height = 400;
canvas.Width = 400;
canvas.Background = new SolidColorBrush(Colors.Red);
Image img1 = new Image();
img1.Source = (ImageSource)new ImageSourceConverter().ConvertFromString("Image/Desert.jpg");
img1.Height = 300;
img1.Width = 300;
img1.Margin = new Thickness(0, 10, 0, 0);
Image img2 = new Image();
img2.Source = (ImageSource)new ImageSourceConverter().ConvertFromString("Image/Jellyfish.jpg");
img2.Height = 50;
img2.Width = 50;
img2.Margin=new Thickness(0,10,300,0);
canvas.Children.Add(img1);
canvas.Children.Add(img2);
ContentPanel.Children.Add(canvas);
WriteableBitmap wb = new WriteableBitmap(400, 400);
wb.Render(canvas, new MatrixTransform());
MemoryStream ms = new MemoryStream();
wb.SaveJpeg(ms,400,400,0,100);
using (var isoFileStream = new IsolatedStorageFileStream("myPicture.jpg", FileMode.OpenOrCreate, IsolatedStorageFile.GetUserStoreForApplication()))
{
wb.SaveJpeg(isoFileStream, 400, 400, 0, 100);
}
}
When i save the image then i am getting a black screen in isolated storage.
How to save both images on canvas?
Like Stephan said, I think you are not getting the image to your source. Any way I created a sample application for you. In that you can find two partitions, you can add image to that by double tapping on the container. After that try save and check your saved image. I tested the app and every thing is working for me. Still you face any kind of issues please leave a comment.
https://www.dropbox.com/s/1vjbbou96w0r15r/SaveImageApp.zip
Please check weather you are getting image or not to image source. If you are getting the image; try this method to take snapshot from control and save that to Iso store.
http://stackoverflow.com/questions/13837148/how-can-i-take-a-screenshot-full/13990649#13990649
I'm trying to dynamically build a live tile.
It runs fine thanks to some SO suggestions and I have this code:
WriteableBitmap wbmp = new WriteableBitmap(173, 173);
TextBlock text = new TextBlock() { FontSize = (double)Resources["PhoneFontSizeLarge"], Foreground = new SolidColorBrush(Colors.White) };
text.Text = "my text";
wbmp.Render(text, new TranslateTransform() { Y = 20 });
wbmp.Invalidate();
// save image to isolated storage
using (IsolatedStorageFile isf = IsolatedStorageFile.GetUserStoreForApplication())
{
using (IsolatedStorageFileStream imageStream = new IsolatedStorageFileStream("/Shared/ShellContent/MyImage.jpg", System.IO.FileMode.Create, isf))
{
wbmp.SaveJpeg(imageStream, wbmp.PixelWidth, wbmp.PixelHeight, 0, 100);
}
}
The problem is that the tile has a black (or, better, transparent) background. I would like to use accent background color, how can I do it?
Solved in this way:
Canvas can = new Canvas();
can.Background = (SolidColorBrush)Application.Current.Resources["PhoneAccentBrush"];
can.Width = 173;
can.Height = 173;
wbmp.Render(can, null);
You're better to use Resources["TransparentBrush"] as the background, and then save to png, otherwise, your tile will be the wrong color on a theme change.
I'm using flyingsaucer to render HTML to an image, using Java2DRenderer:
Map<Key,Object> renderingHints = new HashMap<Key,Object>();
renderingHints.put(RenderingHints.KEY_INTERPOLATION, RenderingHints.VALUE_INTERPOLATION_BICUBIC);
renderingHints.put(RenderingHints.KEY_RENDERING, RenderingHints.VALUE_RENDER_QUALITY);
renderingHints.put(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
renderingHints.put(RenderingHints.KEY_DITHERING, RenderingHints.VALUE_DITHER_DISABLE);
hints = new RenderingHints(renderingHints);
Java2DRenderer renderer = new Java2DRenderer(dom, width, height);
renderer.setRenderingHints(renderingHints);
renderer.getSharedContext().setDPI(DPI);
renderer.setBufferedImageType(BufferedImage.TYPE_INT_ARGB);
img = renderer.getImage();
Then I add the rendered image to a PDF document, scaling it to fit the entire page.
com.lowagie.text.Document pdf = new com.lowagie.text.Document(isLandscape ? PageSize.A4.rotate() : PageSize.A4);
pdf.setMargins(MARGIN, MARGIN, MARGIN, MARGIN);
Rectangle ps = pdf.getPageSize();
PdfWriter.getInstance(pdf, outputStream);
pdf.open();
com.lowagie.text.Image pdfImage = com.lowagie.text.Image.getInstance(img, null);
pdfImage.scaleAbsolute(
ps.getWidth() - pdf.leftMargin() - pdf.rightMargin(),
ps.getHeight() - pdf.topMargin() - pdf.bottomMargin()
);
pdf.add(pdfImage);
pdf.close();
The problem is that the image rendered by FS has as background color solid white... so the printer fills the entire page with a very light gray (I believe that scaling transforms the solid white into a light grey).
How can I force flyingsaucer generate a transparent image so I can avoid this problem?
For the Java2DRenderer there is a way by subclassing the Java2DRender
final java.awt.Color TRANSPARENT = new Color(255, 255, 255, 0);
final int imageType = BufferedImage.TYPE_INT_ARGB;
final Java2DRenderer java2dRenderer = new Java2DRenderer(doc, width, height) {
#Override
protected BufferedImage createBufferedImage(final int width, final int height) {
final BufferedImage image = org.xhtmlrenderer.util.ImageUtil.createCompatibleBufferedImage(width, height, imageType);
org.xhtmlrenderer.util.ImageUtil.clearImage(image, TRANSPARENT);
return image;
}
};
java2dRenderer.setBufferedImageType(imageType);