JRViewer freezing when displaying full page images - java

I am using a JasperViewer to display the report inside of a Java desktop application.
The report consists of 2 pages - each of them represents an image.
The problem is, when user scrolls the page inside the viewer, there are huge freezes.
The size of image isn't so big, about 1000x1000.
The image is generated in this way:
private BufferedImage createImage(Component panel) {
int w = (int) panel.getSize().getWidth();
int h = (int) panel.getSize().getHeight();
BufferedImage bi = new BufferedImage(w, h, BufferedImage.TYPE_INT_RGB);
Graphics2D g = bi.createGraphics();
panel.paint(g);
g.dispose();
return bi;
}

You have two choices
1) put your image as Icon to JLabel
2) for Swing JComponets is there paintComponent() instead of paint(),
please read tutorial about Graphics
tons of examples on this forum (Swing tagged),

The issue is resolved. There is a parameter in the JRViewer:
//Maximum size (in pixels) of a buffered image that would be used by {#link JRViewer JRViewer} to render a report page.
//If rendering a report page would require an image larger than this threshold
//(i.e. image width x image height > maximum size), the report page will be rendered directly on the viewer component.
//If this property is zero or negative, buffered images will never be user to render a report page.
//By default, this property is set to 0.
public static final String VIEWER_RENDER_BUFFER_MAX_SIZE
So, if this parameter is set, the reports is drawn as an ImageIcon on a JLabel. Otherwise, it's drawn using JRGraphics2DExporter that is much more slower when working with big images.
So the solution is to set the specified property in the property file or using way like this:
/**
* This number represents maximum size of an image ( x*y )
* So this value cover up to 300% zoom for an image 1000x1000 pixels
*/
public static final String MAX_PIXELS_NUMBER = "10000000";
static {
try {
JRProperties.setProperty(JRViewer.VIEWER_RENDER_BUFFER_MAX_SIZE, MAX_PIXELS_NUMBER);
} catch (Exception e) {
System.err.println("Cannot set the VIEWER_RENDER_BUFFER_MAX_SIZE property. Reports will be rendered slowly.");
}
}

Related

Scaling an image on a button which is resized

I'm working on an application which allows a used to place controls, move, resize, etc. But I'm trying to add icon images to a button control. When placed and instanced, it resizes the icon image per the code below.
But when I resize the control using user features and it calls this routing again, it fails to resize the image and it remains the original icon size. I've tried using "this.", passing the control to itself, I've done prints to ensure it's seeing the new size and width... what I am missing?
Also, when I create a 2nd control (or 3rd, etc), it uses the 1st image's initial size.
Thanks!
protected void sizeIcon () {
try {
File f2 = new File("media\\button.gif");
BufferedImage inputImage = ImageIO.read(f2);
BufferedImage img = new BufferedImage(this.getWidth(), this.getHeight(), inputImage.getType());
Graphics2D g = img.createGraphics();
g.drawImage(inputImage, 7, 0, this.getWidth(), this.getHeight(), null);
ImageIO.write(img, "gif", new File("test.gif"));
this.setIcon(new ImageIcon("test.gif"));
g.dispose();
} catch(Exception e) {System.out.println(e);}
Sorry, got it, appears the old file was not being replaces.
-MH

resize image from a height [duplicate]

This question already has answers here:
Java: maintaining aspect ratio of JPanel background image
(4 answers)
Closed 7 years ago.
I have a program that sends the image from frontend (angularjs) to java controller. In controller I am geting a byte array. I can save this image but I would like to resize this image before I saveing. The problem is that I want to set fixed height of the picture, and the change of width should take place proportionately to the height. This procedure should be universal so that it can be applicable to different photos.
Below is my code:
#RequestMapping(value = "/rest/bookImage", method = RequestMethod.POST)
public #ResponseBody MessageDTO UploadFile(
MultipartHttpServletRequest request, HttpServletResponse response) {
Iterator<String> itr = request.getFileNames();
MultipartFile file = request.getFile(itr.next());
FileOutputStream fos;
fos = new FileOutputStream(urlImage);
fos.write(file.getBytes());
fos.close();
}
Since you have the image already, you can use the getScaledInstance function:
yourImage.getScaledInstance(newWidth, newHeight, Image.SCALE_DEFAULT);
You say you want the width to be proportionate to the height, by choosing if you want it to be double or whatever (just set the appropriate height and width respectively!)
See more info here : http://docs.oracle.com/javase/7/docs/api/java/awt/Image.html
public Image getScaledInstance(int width,
int height,
int hints)
Creates a scaled version of this image. A new Image object is returned which will render the image at the specified width and height by default.
If either width or height is a negative number then a value is substituted to maintain the aspect ratio of the original image dimensions. If both width and height are negative, then the original image dimensions are used.
Parameters:
width - the width to which to scale the image.
height - the height to which to scale the image.
hints - flags to indicate the type of algorithm to use for image resampling.
Returns: a scaled version of the image.

Java GUI image size

So I have an assignment where I need to create a catalog.
The catalog needs to have a list, an image and a description.
My entire code works, so I have no issue with the coding as such.
I do have an issue with the image size.
How do I take care of images on a java gui program to make them all into one size when it is running.
Please let me know :D
When you read in an image, create a new BufferedImage that is the exact size that you desire, get it's Graphics object via getGraphics(), draw the original image into the new image using Graphics#drawImage(Image img, int x, int y, int width, int height, ImageObserver observer) where x and y are 0 and width and height are from the dimensions of the new image, dispose() of the Graphics object, and then display the new Image as an ImageIcon in a JLabel. Make sure though that the original image is the same size or larger than the new one, else your images will look gawd-awful.
For example, and note that this code may not be exactly correct since I don't have my IDE up:
BufferedImage originalImage = ImageIO.read(something); // read in original image
// create new empty image of desired size
BufferedImage newImage = new BufferedImage(desiredWidth, desiredHeight, BufferedImage.TYPE_INT_ARGB);
Graphics g = newImage.getGraphics(); // get its graphics object
// draw old image into new image
g.drawImage(originalImage, 0, 0, desiredWidth, desiredHeight, null);
g.dispose(); // get rid of Graphics object
// create ImageIcon and put in JLabel to display
Icon newIcon = new ImageIcon(newImage);
myJLabel.setIcon(newIcon);
I would propably create a JPanel to draw on one Image, and then work with the method:
myPanel.setSize(new Dimension(x,y))
or
myPanel.setPreferredSize(new Dimension....)
There is a method (image = imgobj.getScaledInstance(width, height, hints)) in awt.Image class which provides re-sizing capabilities very nicely, I always use this to re-size my images when I need. Please see here some examples :-), I hope it will work for you, it is the most convenient way to scale images I have ever seen. create a method pass the image to the method and size of the image you want and return the image back in return to reuse the code ;)

Prepending an image to the top of another image

I've been looking for a solution for the last several days.
I've seen an example of composite images with Java Advanced Imaging. But that seems to be restricted by the smallest width and height of either image files. So it outputs a file with the height and width of the header file.
Preferably, I'd like to have the header not covering any part of the body image. But it's not a requirement. Sometimes the body image's width is smaller than the header and that's fine as the main content of the header file will be in the middle.
Using JDK 1.6.0_41, I need to take the first two images:
And have the result be:
Whether it is using Java or Javscript is fine. The entire process is as follows:
I take a canvas object of a map using OpenLayers, then use a POST to send it to a Java Servlet to be processed and stored. Then later retrieved the image if the user desires.
The long blue header needs to be at the top of an image or just above it. The header image will have content from the user that created it, etc. That I can do. But manipulating multiple images is not something I am familiar with.
In Java, you can do this:
public BufferedImage prependImage(BufferedImage image1, BufferedImage image2) {
Dimension d1 = new Dimension(image1.getWidth(null),
image1.getHeight(null));
Dimension d2 = new Dimension(image2.getWidth(null),
image2.getHeight(null));
Dimension dt = new Dimension(d1.width, d1.height + d2.height);
BufferedImage image = new BufferedImage(dt.width, dt.height,
BufferedImage.TYPE_INT_ARGB);
Graphics g = image.getGraphics();
int x = 0;
int y = 0;
g.drawImage(image1, x, y, d1.width, d1.height, null);
y += d1.height;
g.drawImage(image2, x, y, d2.width, d2.height, null);
g.dispose();
return image;
}

BufferedImage colour change

I have working on an application which captures screen shots and create video from captured images. But the problem is that when video is generated, colours in generated video is very pinkish. I think this is because I am manipulating captured images to show cursor using BufferedImage.TYPE_3BYTE_BGR type. Could someone tell me how to resolve this issue, I want to have the colour of video same as actual colour of screen.
For capturing screen image I am doing as follows:
Robot robot = new Robot();
Rectangle captureSize = new Rectangle(screenBounds);
return robot.createScreenCapture(captureSize);
For manipulating images I am doing as follows:
image = new BufferedImage(sourceImage.getWidth(), sourceImage.getHeight(), BufferedImage.TYPE_3BYTE_BGR);
if (true) {
int x = MouseInfo.getPointerInfo().getLocation().x - 25;
int y = MouseInfo.getPointerInfo().getLocation().y - 37;
Graphics2D graphics2D = sourceImage.createGraphics();`enter code here`
graphics2D.drawImage(SimpleWebBrowserExample.m_MouseIcon, x, y, 48, 48, null);
}
image.getGraphics().drawImage(sourceImage, 0, 0, null);
return image;
please tell me how to get the images with colour same as actual colour on screen.
Thanks.
Use BufferedImage.TYPE_INT_ARGB or BufferedImage.TYPE_INT_RGB, as shown in this example. If you need to change the colors, you can use a LookupOp with a four-component LookupTable that adjusts the alpha component as required for BufferedImage.TYPE_3BYTE_BGR: "When data with non-opaque alpha is stored in an image of this type, the color data must be adjusted to a non-premultiplied form and the alpha discarded." Examples may be found in Using the Java 2D LookupOp Filter Class to Process Images and Image processing with Java 2D.
See the the "pinkish" explanation here
Basically the image is saved as a ARGB and most viewers interpret it as a CMYK. Alpha is preserved when opening it back in Java, though.

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