Develop Reference

Is there a function that converts any image into a circle of 150x150 pixels-java?

I need a function/method that can mold(crop and resize) an imported (.png format) image into a circle of exact 150x150 pixels and it should keep transparency. I have searched all over internet, also I have my own code but I think its completely useless. I need this function for a code I am using to make GUI of a social-media app database.
private ImageIcon logo = new ImageIcon(getClass().getResource("/test/test200x200.png"));
toCircle(logo);
I need the code for the following function:
public ImageIcon toCircle(ImageIcon icon)
{
//code
return icon;
}
This function should convert this picture:
To this:

Create a new transparent image
Get a Graphics object from the image.
Set a clip for the graphics object.
Paint the PNG format image.
See also this answer that uses a clipped region.

An alternative approach, that might be more straight-forward to implement for this use case, is:
Create a transparent BufferedImage the size of your icon
Create Graphics2D from image, set hints for antialias
Fill a circle the size of your background circle
Draw the image on top of your circle, using AlphaComposite.SrcIn
Something like:
public Icon toCircle(ImageIcon logo) {
BufferedImage image = new BufferedImage(150, 150); // Assuming logo 150x150
Graphics2D g = image.createGraphics();
g.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
g.fillOval(1, 1, 148, 148); // Leaving some room for antialiasing if needed
g.setComposite(AlphaComposite.SrcIn);
g.drawImage(logo.getImage(), 0, 0, null);
g.dispose();
return new ImageIcon(image);
}

How to resize an image in a panel with OpenImaj

I use OpenImaj for a project and I need to display the video in 800*600 to a panel but I must capture images at 1920,1080 when I click a button.
My strategy was initially to capture from my webcam at 1920,1080 and to resize image in a icon of a label contained in my panelVideo.
My problem is that the performance is very low.
Is there an efficient method to resize video according to the size of panelVideo without changing the frame size (that I use for saving the image at 1920,1080)?
Thank you for your answer.
Regards.
final VideoCapture vc = new VideoCapture(1920,1080);
vc.setFPS(10);
final VideoDisplay<MBFImage> display = VideoDisplay.createVideoDisplay(vc, panelVideo);
display.addVideoListener(new VideoDisplayAdapter<MBFImage>()
{
#Override
public void beforeUpdate(final MBFImage frame)
{
//here I create a bufferedImage from the resized frame
BufferedImage img = new BufferedImage(800, 600, BufferedImage.TYPE_INT_ARGB);
Graphics2D g = (Graphics2D) img.getGraphics();
g.drawImage(ImageUtilities.createBufferedImageForDisplay(frame), 0, 0, 800, 600, null);
//here is the label that I use to display the video
labelVideo.setIcon(new ImageIcon(ImageUtilities.createBufferedImageForDisplay(frame)));
}
});

You can at least remove fixed code like this out of the loop - that is create it only once
//here I create a bufferedImage from the resized frame
BufferedImage img = new BufferedImage(800, 600, BufferedImage.TYPE_INT_ARGB);
Graphics2D g = (Graphics2D) img.getGraphics();
and also have the Icon created once and setImage() as needed. Beyond that I dont know how to convert MBF to BufferedImage thats the pain of using different libraries. g.drawImage() is a good way to draw the scaled image.

See http://openimaj.org/apidocs/org/openimaj/image/processing/resize/package-frame.html for the OpenIMAJ classes that let you resize an MBFImage. You'll have to play and see what is fastest, but in my very quick experiments I found BilinearInterpolation to be better than ResizeProcessor with the default options, however using a different filter in ResizeProcessor might be faster.
Rather than creating a new BufferedImage each frame, you would probably be better off drawing the MBFImage into a Swing component that displays them directly: http://openimaj.org/apidocs/org/openimaj/image/DisplayUtilities.ScalingImageComponent.html or http://openimaj.org/apidocs/org/openimaj/image/DisplayUtilities.ImageComponent.html (note that technically these both convert to BufferedImage behind the scenes, but they only allocate the image once and just redraw into it saving a lot of time).

Adding some pictures to a BuffredImage then Save it

My general idea is to make a Sprite-Sheet-Maker I mean the program will:
Collect more than one picture like "1.bmp" , "2.png" and "3.jpg"
Create new BuffredImage variable and draw on it the 3 pictures (and draw the BuffredImage on a JPanel on the same time)
Save the final picture "Final.png"
I'm thinking to make the First step and the Second one in one loop because i have a JList with the paths of all the pictures.
and to do that I used Java window Builder on eclipse, I made my form and I tried to test a simple code on the Panel.
Panel panel = new Panel(); //Work
panel.setBackground(Color.BLUE); //Work
BufferedImage img = new BufferedImage(5,5,5); //Work
Graphics g = null ; //Work
panel.paintComponents(g); //work
g.setColor(Color.BLACK); //ERROR---------------------ERROR
g.fillRect(0, 0, 50, 50);
The problem it's not only in that code but in all the idea so please any of your ideas could help me even a part of solution for a part of my project , so please comment with any idea you've got.

g.setColor(Color.BLACK);//error
Since
Graphics g = null ;//null value, you are not create any obeject
Upon null value we can't perform any operation.
You have to override paintComponent method in JPanel class then you will receive Graphics object.
JPanel panel = new JPanel() {
#Override
public void paintComponent(Graphics g) {
super.paintComponent(g);
g.setColor(Color.BLUE);
g.fillRect(0, 0, 100, 100);
}
};
frame.add(panel);//added to frame.
See this link

Create a JPanel using a GridLayout.
Create 3 JLabel each containing an Icon for each image. Then add each label to the panel.
To create an image of any Swing component you can use the Screen Image class.

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 ;)

Creating a sized image out of a string in Java

I am making a 2d engine using Java based on entities. The physics and sprites are done, but I still need to be able to draw text with the BaseText class. For experimental purposes I am using the following code in the Renderer class (that handles drawing all the sprites and such):
BufferGraphics.drawString(((BaseText) Entity).getText(), (int) -(Origin.getX() * PositionTransform), (int) -Origin.getY());
I would like to, however, be able to either move this code into the setText(final String Text) method of the BaseText entity, i.e. when it is called a new image is created containing the text specified (possibly in different fonts and sizes and such, I haven't decided).
My problem is this: I would like to be able to resize (scale) the text to my liking. It would also be nice to have the text converted to an image as I can get the dimensions of it and set the size of the text entity itself.
Basically, what I need follows something along these lines:
Take desired string and feed it into the setText method.
Take the string and draw it onto an image, sized so that the text will fit into it exactly.
Set this new image to the Image field in the entity so that the engine can draw it.
Is this even possible? There may be a way to do this with the FontMetrics class or whatever it may be called, but I'm not so sure as I have not used it before.
Edit : Let me clarify: I want to create a BufferedImage based on the size of some text set to a specific font and size, not size the text to fit an image.
Edit 2: Thanks to this fellow Andrew, whom so graciously provided code, I was able to add some code to the engine that, by all means, just plain should work. Again, however, not even with that drawRect in there, the image either remains either transparent or somehow is not getting drawn. Let me supply some breadcrumbs: -snip-
The stupid thing is that all the other sprites and images and such draw fine, so I am not sure how it could be the Renderer.
By the way, that was the paint() method.
Edit 3:
...
Uh...
...
Oh my.
I am...
...
Text can not explain how hard I belted myself in the face with my left palm.
BaseText.java
#Override
public BufferedImage getImage() {return null;}
Renderer.java
BufferedImage Image = Entity.getImage();
I am
a huge idiot.
Thank you, Andrew, for that code. It worked fine.
Edit 4: By the way, here's the final code that I used:
public void setText(final String Text)
{
Graphics2D Draw = (Graphics2D) Game.View.getBuffer().getDrawGraphics();
FontMetrics Metrics = Draw.getFontMetrics();
Rectangle2D Bounds = Metrics.getStringBounds(Text, Draw);
BufferedImage NewImage = new BufferedImage((int) Bounds.getWidth(), (int) (Bounds.getHeight() + Metrics.getDescent()), BufferedImage.TYPE_INT_RGB);
Draw = (Graphics2D) NewImage.getGraphics();
Draw.setColor(new Color(0xAAFF0000));
Draw.drawRect(0, 0, NewImage.getWidth(), NewImage.getHeight());
Draw.drawString(Text, 0, (int) Bounds.getHeight());
this.Image = NewImage;
this.Text = Text;
this.setSize(new Vector(NewImage.getWidth(), NewImage.getHeight()));
}

Use FontMetrics, GlyphView or the preferred size a JLabel (handy for getting the size needed to display formatted text.
Adjust the sizes of the font in step 1 until it fits. Call BufferedImage.createGraphics() to get a Graphics2D object. Paint the String to that.
I do not understand point 3, so won't comment.
Here is how it would work with either FontMetrics or a JLabel.
import java.awt.*;
import java.awt.image.*;
import java.awt.geom.Rectangle2D;
import javax.swing.*;
class TextSize {
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
// Technique 1 - FontMetrics
String s = "The quick brown fox jumps over the lazy dog!";
BufferedImage bi = new BufferedImage(
1,
1,
BufferedImage.TYPE_INT_RGB);
Graphics g = bi.getGraphics();
FontMetrics fm = g.getFontMetrics();
Rectangle2D b = fm.getStringBounds(s,g);
System.out.println(b);
bi = new BufferedImage(
(int)b.getWidth(),
(int)(b.getHeight() + fm.getDescent()),
BufferedImage.TYPE_INT_RGB);
g = bi.getGraphics();
g.drawString(s,0,(int)b.getHeight());
JOptionPane.showMessageDialog(
null,
new JLabel(new ImageIcon(bi)));
// Technique 3 - JLabel
JLabel l = new JLabel(s);
l.setSize(l.getPreferredSize());
bi = new BufferedImage(
l.getWidth(),
l.getHeight(),
BufferedImage.TYPE_INT_RGB);
g = bi.getGraphics();
g.setColor(Color.WHITE);
g.fillRect(0,0,400,100);
l.paint(g);
JOptionPane.showMessageDialog(
null,
new JLabel(new ImageIcon(bi)));
}
});
}
}