hi I want to open a image file with openfiledialog and resize to upload to database so please help me with this code which I got from some where but I don't know how to make it working thanks
private void ResizeImg(double scaleFactor, Stream sourcePath, string tragetPath)
{
using (var image = System.Drawing.Image.FromStream(sourcePath))
{
var newWidth = (int)(image.Width * scaleFactor);
var newHeight = (int)(image.Height * scaleFactor);
var resizingImg = new Bitmap(newWidth, newHeight);
var resizeGraph = Graphics.FromImage(resizingImg);
resizeGraph.CompositingQuality = CompositingQuality.HighQuality;
resizeGraph.SmoothingMode = SmoothingMode.HighQuality;
resizeGraph.InterpolationMode = InterpolationMode.HighQualityBicubic;
var imageRectangle = new Rectangle(0, 0, newWidth, newHeight);
resizeGraph.DrawImage(image, imageRectangle);
resizingImg.Save(targetPath, image.RawFormat);
}
}
Without specifying source and target rectangle, it doesn't stretch.
Change
resizeGraph.DrawImage(image, imageRectangle);
to
var srcRectangle = new Rectangle(0, 0, image.Width, image.Height);
resizeGraph.DrawImage(image, imageRectangle,srcRectangle, GraphicsUnit.Pixel);
BTW: Consider ImageFormat.Jpeg or .Png for Save, because you cannot write all image formats you can read.
Related
I am working on xamarin.forms. I have to select images from gallery and then resize them and then upload them on server. But I don't know how I can resize selected image in a given particular size?
Please update me how I can do this?
This can be used with a stream (if you're using the Media Plugin https://github.com/jamesmontemagno/MediaPlugin) or standard byte arrays.
// If you already have the byte[]
byte[] resizedImage = await CrossImageResizer.Current.ResizeImageWithAspectRatioAsync(originalImageBytes, 500, 1000);
// If you have a stream, such as:
// var file = await CrossMedia.Current.PickPhotoAsync(options);
// var originalImageStream = file.GetStream();
byte[] resizedImage = await CrossImageResizer.Current.ResizeImageWithAspectRatioAsync(originalImageStream, 500, 1000);
I tried use CrossImageResizer.Current... but I did not find it in the Media Plugin. Instead I found an option called MaxWidthHeight, that worked only if you also add PhotoSize = PhotoSize.MaxWidthHeight option.
For Example :
var file = await CrossMedia.Current.PickPhotoAsync(new PickMediaOptions() { PhotoSize = PhotoSize.MaxWidthHeight, MaxWidthHeight = 600 });
var file = await CrossMedia.Current.TakePhotoAsync(new StoreCameraMediaOptions { PhotoSize = PhotoSize.MaxWidthHeight, MaxWidthHeight = 600 });
Sadly enough there isn't a good cross-platform image resizer (that I've found at the time of this post). Image processing wasn't really designed to take place in a cross-platform environment for iOS and Android. It's much faster and cleaner to perform this on each platform using platform-specific code. You can do this using dependency injection and the DependencyService (or any other service or IOC).
AdamP gives a great response on how to do this Platform Specific Image Resizing
Here is the code taken from the link above.
iOS
public class MediaService : IMediaService
{
public byte[] ResizeImage(byte[] imageData, float width, float height)
{
UIImage originalImage = ImageFromByteArray(imageData);
var originalHeight = originalImage.Size.Height;
var originalWidth = originalImage.Size.Width;
nfloat newHeight = 0;
nfloat newWidth = 0;
if (originalHeight > originalWidth)
{
newHeight = height;
nfloat ratio = originalHeight / height;
newWidth = originalWidth / ratio;
}
else
{
newWidth = width;
nfloat ratio = originalWidth / width;
newHeight = originalHeight / ratio;
}
width = (float)newWidth;
height = (float)newHeight;
UIGraphics.BeginImageContext(new SizeF(width, height));
originalImage.Draw(new RectangleF(0, 0, width, height));
var resizedImage = UIGraphics.GetImageFromCurrentImageContext();
UIGraphics.EndImageContext();
var bytesImagen = resizedImage.AsJPEG().ToArray();
resizedImage.Dispose();
return bytesImagen;
}
}
Android
public class MediaService : IMediaService
{
public byte[] ResizeImage(byte[] imageData, float width, float height)
{
// Load the bitmap
BitmapFactory.Options options = new BitmapFactory.Options();// Create object of bitmapfactory's option method for further option use
options.InPurgeable = true; // inPurgeable is used to free up memory while required
Bitmap originalImage = BitmapFactory.DecodeByteArray(imageData, 0, imageData.Length, options);
float newHeight = 0;
float newWidth = 0;
var originalHeight = originalImage.Height;
var originalWidth = originalImage.Width;
if (originalHeight > originalWidth)
{
newHeight = height;
float ratio = originalHeight / height;
newWidth = originalWidth / ratio;
}
else
{
newWidth = width;
float ratio = originalWidth / width;
newHeight = originalHeight / ratio;
}
Bitmap resizedImage = Bitmap.CreateScaledBitmap(originalImage, (int)newWidth, (int)newHeight, true);
originalImage.Recycle();
using (MemoryStream ms = new MemoryStream())
{
resizedImage.Compress(Bitmap.CompressFormat.Png, 100, ms);
resizedImage.Recycle();
return ms.ToArray();
}
}
WinPhone
public class MediaService : IMediaService
{
private MediaImplementation mi = new MediaImplementation();
public byte[] ResizeImage(byte[] imageData, float width, float height)
{
byte[] resizedData;
using (MemoryStream streamIn = new MemoryStream(imageData))
{
WriteableBitmap bitmap = PictureDecoder.DecodeJpeg(streamIn, (int)width, (int)height);
float Height = 0;
float Width = 0;
float originalHeight = bitmap.PixelHeight;
float originalWidth = bitmap.PixelWidth;
if (originalHeight > originalWidth)
{
Height = height;
float ratio = originalHeight / height;
Width = originalWidth / ratio;
}
else
{
Width = width;
float ratio = originalWidth / width;
Height = originalHeight / ratio;
}
using (MemoryStream streamOut = new MemoryStream())
{
bitmap.SaveJpeg(streamOut, (int)Width, (int)Height, 0, 100);
resizedData = streamOut.ToArray();
}
}
return resizedData;
}
}
EDIT: If you are already using FFImageLoading in your project then you can just use that for your platform.
https://github.com/luberda-molinet/FFImageLoading
I fixed in my project, this was the best way for me .
when take photo or get image from gallery you can change size with properties
var file = await CrossMedia.Current.TakePhotoAsync(new StoreCameraMediaOptions
{
PhotoSize = PhotoSize.Custom,
CustomPhotoSize = 90 //Resize to 90% of original
});
for more information: https://github.com/jamesmontemagno/MediaPlugin
I am working on a windows phone 8.1 app where I need to convert a polygon object to an image and ultimately save it as a png file. Till now, I created a polygon object with various properties. Now I'm clueless about the other parts.
pol.Opacity = 0.5;
System.Windows.Point Point1 = new System.Windows.Point(10, 200);
System.Windows.Point Point2 = new System.Windows.Point(60, 140);
System.Windows.Point Point3 = new System.Windows.Point(130, 140);
System.Windows.Point Point4 = new System.Windows.Point(180, 200);
System.Windows.Point Point5 = new System.Windows.Point(130, 260);
System.Windows.Point Point6 = new System.Windows.Point(60, 260);
PointCollection myPointCollection = new PointCollection();
myPointCollection.Add(Point1);
myPointCollection.Add(Point2);
myPointCollection.Add(Point3);
myPointCollection.Add(Point4);
myPointCollection.Add(Point5);
myPointCollection.Add(Point6);
pol.Points = myPointCollection;
var imageBrush = new ImageBrush();
imageBrush.ImageSource = image.Source;
pol.Fill = imageBrush;
pol.Height = image.Height;
pol.MaxHeight = image.Height;
pol.MaxWidth = image.Width;
pol.Width = image.Width;
pol.Stroke = new SolidColorBrush(Colors.Red);
pol.StrokeThickness = 2;
pol.Margin = image.Margin;
You can use the WritableBitmap class in order to achieve this. I have a similar post on Silverlight, which you can refer: How to Crop an Image based on a Shape or Path control?. Hope that helps, at least gives some basic concepts. Let me know, if you need further help on this.
To save the shape as PNG, you can utilize the following code snippet:
WriteableBitmap bmp = GetAsWritableBitmap();
using (var mediaLibrary = new MediaLibrary())
{
using (var stream = new MemoryStream())
{
var fileName = string.Format("Gs{0}.jpg", Guid.NewGuid());
bmp.SaveJpeg(stream, bmp.PixelWidth, bmp.PixelHeight, 0, 100);
stream.Seek(0, SeekOrigin.Begin);
var picture = mediaLibrary.SavePicture(fileName, stream);
if (picture.Name.Contains(fileName)) return true;
}
}
Hope that helps.
This is the code i wrote to resize the image in aspect ratio, it works on chrome but not display on firefox, does anyone know what is wrong.
var image = new Image();
image.src = data;
//$(image).load(function () {
var aspectRatio = getAspectRatio(parseFloat($(image).prop('naturalWidth')),
parseFloat($(image).prop('naturalHeight')),
dstWidth,
dstHeight);
var canvas = document.createElement('canvas');
canvas.width = dstWidth;
canvas.height = dstHeight;
var x = (dstWidth - aspectRatio[0]) / 2;
var y = (dstHeight - aspectRatio[1]) / 2;
var ctx = canvas.getContext("2d");
ctx.drawImage(image, x, y, aspectRatio[0], aspectRatio[1]);
return canvas.toDataURL("image/png");
This is work it generated by the canvas.toDataURL
data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAQEAAADACAYAAAAEL9ZYAAAA1klEQVR4nO3BAQ0AAADCoPdPbQ8HFAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAADwYD7QAB/UrDfgAAAABJRU5ErkJggg==
To make it work you will need to handle the asynchronous nature of image loading. You will have to use a callback mechanism here. The reason it "works" in Chrome is accident; that is the image happen to be in the cache when you try and/or the browser is able to deliver the uncompressed/decoded image before you use the image in the drawImage call.
This will probably not work when it's online for most users so to properly handle loading you can do -
Example:
function getImageUri(url, callback) {
var image = new Image();
image.onload = function () { // handle onload
var image = this; // make sure we using valid image
var aspectRatio = getAspectRatio(parseFloat($(image).prop('naturalWidth')),
parseFloat($(image).prop('naturalHeight')),
dstWidth,
dstHeight);
var canvas = document.createElement('canvas');
canvas.width = dstWidth;
canvas.height = dstHeight;
var x = (dstWidth - aspectRatio[0]) / 2;
var y = (dstHeight - aspectRatio[1]) / 2;
var ctx = canvas.getContext("2d");
ctx.drawImage(image, x, y, aspectRatio[0], aspectRatio[1]);
// use callback to provide the finished data-uri
callback(canvas.toDataURL());
}
image.src = url; // set src last
}
Then use it this way:
getImageUri(myURL, function (uri) {
console.log(uri); // contains the image as data-uri
});
tried searching for something like this, but I've had no luck. I'm trying to open a new tab with a screenshot of the current state of my webgl image. Basically, it's a 3d model, with the ability to change which objects are displayed, the color of those objects, and the background color. Currently, I am using the following:
var screenShot = window.open(renderer.domElement.toDataURL("image/png"), 'DNA_Screen');
This line succeeds in opening a new tab with a current image of my model, but does not display the current background color. It also does not properly display the tab name. Instead, the tab name is always "PNG 1024x768".
Is there a way to change my window.open such that the background color is shown? The proper tab name would be great as well, but the background color is my biggest concern.
If you open the window with no URL you can access it's entire DOM directly from the JavaScript that opened the window.
var w = window.open('', '');
You can then set or add anything you want
w.document.title = "DNA_screen";
w.document.body.style.backgroundColor = "red";
And add the screenshot
var img = new Image();
img.src = someCanvas.toDataURL();
w.document.body.appendChild(img);
Well it is much longer than your one liner but you can change the background color of the rectangle of the context.
printCanvas (renderer.domElement.toDataURL ("image/png"), width, height,
function (url) { window.open (url, '_blank'); });
// from THREEx.screenshot.js
function printCanvas (srcUrl, dstW, dstH, callback)
{
// to compute the width/height while keeping aspect
var cpuScaleAspect = function (maxW, maxH, curW, curH)
{
var ratio = curH / curW;
if (curW >= maxW && ratio <= 1)
{
curW = maxW;
curH = maxW * ratio;
}
else if (curH >= maxH)
{
curH = maxH;
curW = maxH / ratio;
}
return { width: curW, height: curH };
}
// callback once the image is loaded
var onLoad = function ()
{
// init the canvas
var canvas = document.createElement ('canvas');
canvas.width = dstW;
canvas.height = dstH;
var context = canvas.getContext ('2d');
context.fillStyle = "black";
context.fillRect (0, 0, canvas.width, canvas.height);
// scale the image while preserving the aspect
var scaled = cpuScaleAspect (canvas.width, canvas.height, image.width, image.height);
// actually draw the image on canvas
var offsetX = (canvas.width - scaled.width ) / 2;
var offsetY = (canvas.height - scaled.height) / 2;
context.drawImage (image, offsetX, offsetY, scaled.width, scaled.height);
// notify the url to the caller
callback && callback (canvas.toDataURL ("image/png")); // dump the canvas to an URL
}
// Create new Image object
var image = new Image();
image.onload = onLoad;
image.src = srcUrl;
}
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.