I'm making a Java Swing application that has the following layout (MigLayout
):
[icon][icon][icon][....]
where icon = jlabel and the user can add more icons
When the user adds or removes icons, the others should shrink or grow.
My question is really straightforward: I have a JLabel
which contains an ImageIcon
; how can I resize this icon?
One (quick & dirty) way to resize images it to use HTML & specify the new size in the image element. This even works for animated images with transparency.
This will keep the right aspect ratio.
public ImageIcon scaleImage(ImageIcon icon, int w, int h)
{
int nw = icon.getIconWidth();
int nh = icon.getIconHeight();
if(icon.getIconWidth() > w)
{
nw = w;
nh = (nw * icon.getIconHeight()) / icon.getIconWidth();
}
if(nh > h)
{
nh = h;
nw = (icon.getIconWidth() * nh) / icon.getIconHeight();
}
return new ImageIcon(icon.getImage().getScaledInstance(nw, nh, Image.SCALE_DEFAULT));
}
Try this :
ImageIcon imageIcon = new ImageIcon("./img/imageName.png"); // load the image to a imageIcon
Image image = imageIcon.getImage(); // transform it
Image newimg = image.getScaledInstance(120, 120, java.awt.Image.SCALE_SMOOTH); // scale it the smooth way
imageIcon = new ImageIcon(newimg); // transform it back
(found it here)
And what about it?:
ImageIcon imageIcon = new ImageIcon(new ImageIcon("icon.png").getImage().getScaledInstance(20, 20, Image.SCALE_DEFAULT));
label.setIcon(imageIcon);
I agree this code works, to size an ImageIcon from a file for display while keeping the aspect ratio I have used the below.
/*
* source File of image, maxHeight pixels of height available, maxWidth pixels of width available
* @return an ImageIcon for adding to a label
*/
public ImageIcon rescaleImage(File source,int maxHeight, int maxWidth)
{
int newHeight = 0, newWidth = 0; // Variables for the new height and width
int priorHeight = 0, priorWidth = 0;
BufferedImage image = null;
ImageIcon sizeImage;
try {
image = ImageIO.read(source); // get the image
} catch (Exception e) {
e.printStackTrace();
System.out.println("Picture upload attempted & failed");
}
sizeImage = new ImageIcon(image);
if(sizeImage != null)
{
priorHeight = sizeImage.getIconHeight();
priorWidth = sizeImage.getIconWidth();
}
// Calculate the correct new height and width
if((float)priorHeight/(float)priorWidth > (float)maxHeight/(float)maxWidth)
{
newHeight = maxHeight;
newWidth = (int)(((float)priorWidth/(float)priorHeight)*(float)newHeight);
}
else
{
newWidth = maxWidth;
newHeight = (int)(((float)priorHeight/(float)priorWidth)*(float)newWidth);
}
// Resize the image
// 1. Create a new Buffered Image and Graphic2D object
BufferedImage resizedImg = new BufferedImage(newWidth, newHeight, BufferedImage.TYPE_INT_RGB);
Graphics2D g2 = resizedImg.createGraphics();
// 2. Use the Graphic object to draw a new image to the image in the buffer
g2.setRenderingHint(RenderingHints.KEY_INTERPOLATION, RenderingHints.VALUE_INTERPOLATION_BILINEAR);
g2.drawImage(image, 0, 0, newWidth, newHeight, null);
g2.dispose();
// 3. Convert the buffered image into an ImageIcon for return
return (new ImageIcon(resizedImg));
}
Source: Stackoverflow.com