When I save an image in a JOGL 2 application, the image is rendered in different shades of red, rather than the expected colors.
Here is the code I use to save the image:
AWTGLReadBufferUtil glReadBufferUtil = new AWTGLReadBufferUtil(gl.getGL2().getGLProfile(), false);
BufferedImage image = glReadBufferUtil.readPixelsToBufferedImage(gl.getGL2(), true);
ImageIO.write(image, "png", outputfile);
Any hints how to troubleshoot this problem would be appreciated.
Related
Is there a quick way using System.Drawing to quickly enlarge the image canvas of an .png image? (see example below). The caveat is the background might be transparent and I want to keep it transparent.
Edit: Needs to be in ASP .Net CORE
Alternatively, is there a way of putting the image on a white background that is slightly larger than the image?
After a few days of trial and error, I think I found something that works
Image overlayImage = //get your image here from file or url.
xloc = //x coord where to start overlay image.
yloc = //y coord where to start overlay image.
canvasWidth = //width of background canvas
canvasHeight = //height of background canvas
Bitmap baseImage = new Bitmap(canvasWidth, canvasHeight, System.Drawing.Imaging.PixelFormat.Format24bppRgb);
using (Graphics graphics = Graphics.FromImage(baseImage))
{
using (System.Drawing.SolidBrush myBrush = new System.Drawing.SolidBrush(System.Drawing.Color.White))
{
graphics.FillRectangle(myBrush, new Rectangle(0, 0, canvasWidth, canvasHeight)); // white rectangle
}
graphics.CompositingMode = CompositingMode.SourceOver;
graphics.DrawImage(overlayImage, xloc, yloc);
} // graphics will be disposed at this line
Is there a way to show a picture/image in a QToolTip?
I want to show small images of keyboard-buttons to explain the user which buttons/shortcuts he can use on that specific widget.
You can easily show images with the following html code:
QToolTip::showText(QCursor::pos(), "<img src=':/icon.png'>Message", this, QRect(), 5000);
This example will show a tooltip with the image from Qt resources and the text for 5 seconds.
For more details, you can see this video: https://youtu.be/X9JD8gKGZ00
Edit1:
If you want to show an image from memory, you can save the QImage/QPixmap to memory (preferably using some lossless compression like PNG) and convert it to base 64 and load it with the html code, like this:
QImage icon = QImage(10, 10, QImage::Format_ARGB32);
icon.fill(QColor(255, 0, 0, 100));
QByteArray data;
QBuffer buffer(&data);
icon.save(&buffer, "PNG", 100);
QString html = QString("<img src='data:image/png;base64, %0'>Message").arg(QString(data.toBase64()));
QToolTip::showText(QCursor::pos(), html, this, QRect(), 5000);
Edit2: Corrected the html string as #Damon Lynch suggests.
With respect to the HTML string, the Python 3 / PyQt equivalent of user2014561's excellent solution to displaying in memory images is like this, assuming a QPixmap (a QImage will work the same):
buffer = QBuffer()
buffer.open(QIODevice.WriteOnly)
pixmap.save(buffer, "PNG", quality=100)
image = bytes(buffer.data().toBase64()).decode()
html = '<img src="data:image/png;base64,{}">'.format(image)
I want to use an ImageView to resize an image, however the image is not being resized:
ImageView imageView = new ImageView(image);
imageView.setPreserveRatio(true);
imageView.setFitHeight(40);
System.out.println("imageview image width = " + imageView.getImage().getWidth());
System.out.println("imageview image height = " + imageView.getImage().getHeight());
The output is
imageview image width = 674.0
imageview image height = 888.0
However, the width should be 40. My ImageView is not attached to any scene and I also don't want to attach it, it shall only be used for image resizing. Is there any way to force the ImageView to resize its image, even though the ImageView is not attached to any scene? The reason I am using an ImageView for resizing is, that I want to resize an Image in RAM, without reading it again from the disk, please see this question for more details.
Thanks for any hint!
Using an ImageView for resizing seems to be very hacky.
A better approach is to convert your Image into a BufferedImage and do the resizing the old way. (JavaFx does not (yet) provide an internal way to resize memory images)
int width = 500; // desired size
int height = 400;
Image original = ...; // fx image
BufferedImage img = new BufferedImage(
(int)original.getWidth(),
(int)original.getHeight(),
BufferedImage.TYPE_INT_ARGB);
SwingFXUtils.fromFXImage(original, img);
BufferedImage rescaled = Scalr.rescaleImage(img, width, heigth); // the actual rescale
// convert back to FX image
WritableImage rescaledFX = new WritableImage(width, heigth);
SwingFXUtils.toFXImage(rescaled, rescaledFX);
Where as Scalr is a nice library for resizing images in native java. Obviously, you can use other/simpler methods of rescaling, but the image quality won't be that nice.
I have a tile list that loads images from a folder within the app.
When i load images with a transparent background it gives the image a white background is there any way to get the image to be transparent?
Thanks!
I'm adding the images from a list of images i loop through
var y:Image = new Image();
y.height = 100;
y.width = 100;
y.id = list[i].MID;
y.source = (list[i].vchImagePath);
y.name = (list[i].vchName);
theArray.addItem(y);
If you use an itemRenderer in your list, you can set the autoDrawBackground property to false.
Dany
Well, the problem may be a simple one but I can't figure it out. I have an image loaded into BitmapData. now I want to take text from a textinput and put it on the BitmapData. Basically it's drawing a text on the BitmapData and get the result as another BitmapData that will consist of the original BitmapData with the text drawn over it on a specified position. What's the best way to achieve this in flex?
To put the text inside a bitmap you can do:
var channelName:TextField = new TextField();
channelName.textColor=0x000000;
channelName.antiAliasType = AntiAliasType.NORMAL;
channelName.alpha=1.0;
var txtFormat:TextFormat = new TextFormat("SansSerif",14,0x000000,true);
channelName.setTextFormat(txtFormat);
var bitmapdata:BitmapData = new BitmapData(
channelName.width, channelName.height, true, 0x000000);
bitmapdata.draw(channelName);
You can't draw over bitmapdata per say, but you could compose it from the data. Since you have BitmapData, it's easy enough to change it to a bitmap (var bitmap:Bitmap = new Bitmap(bitmapData);) and then add it as source for an image.
Now that you have an actual image on the stage, you can now add text above that using what you like (text, label, textarea, etc) and then you can do a Bitmap.draw over the dimensions of the image to get the pixel information back into a BitmapData (under Bitmap.bitmapData).