Re: Scaling an Image to Print on 1 page

From:
Knute Johnson <nospam@rabbitbrush.frazmtn.com>
Newsgroups:
comp.lang.java.programmer
Date:
Tue, 04 Dec 2007 18:39:48 -0800
Message-ID:
<Vbo5j.2136$su4.2127@newsfe14.lga>
ErcFrtz@gmail.com wrote:

On Dec 3, 2:36 pm, Knute Johnson <nos...@rabbitbrush.frazmtn.com>
wrote:

ErcF...@gmail.com wrote:

Hello. I have an application that creates a bufferedimage, but most of
the times it's to big to print all on one page. What I want to do is
scale it to fit on one page. If anyone could show me some example code
on how to do this it would be appreciated. (I have the basic
understanding that I need to get the printable area of the printer and
then scale the image to fit in that but I'm not sure how to implement
this.) Thanks.

 From the docs:

drawImage(Image img, int x, int y, int width, int height, ImageObserver
observer)

Draws as much of the specified image as has already been scaled to fit
inside the specified rectangle.

--

Knute Johnson
email s/nospam/knute/


I guess I'm not quite sure what you're saying I should do. Here is the
code for what I was trying to do:

<code> public BufferedImage resizeImage(BufferedImage bimg)
    {
        PrintRequestAttributeSet aset = new HashPrintRequestAttributeSet();
        aset.add(OrientationRequested.LANDSCAPE);
        MediaPrintableArea printableArea =

(MediaPrintableArea)Service.getSupportedAttributeValues(MediaPrintableArea.class,
null, aset);

        double printWidth = printableArea.getWidth(MediaPrintableArea.INCH);
        double printHeight =
printableArea.getHeight(MediaPrintableArea.INCH);

        int tempW = bimg.getWidth();
        int tempH = bimg.getHeight();
        double bimgWidth = tempW/72;
        double bimgHeight = tempH/72;

        double conversion;
        double Xconv = printWidth/bimgWidth;
        double Hconv = printHeight/bimgHeight;
        if(Xconv > Hconv)
            conversion = Xconv;
        else
            conversion = Hconv;

        int bimgNewW = conversion*tempW;
        int bimgNewH = conversion*tempH;
        BufferedImage newbimg = bimg.getScaledInstance(bimgNewW, bimgNewH,
BufferedImage.SCALE_DEFAULT);


This won't compile. BufferedImage.getScaledInstance() returns an Image.

         return newbimg;
    }</code>

I was expecting you to draw you image in Printable.print(). I haven't
played with document printing in this style before. Try the little
program below. Change the kittens.jpg to your own image and adjust the
PageFormat with the dialog. This will print the image scaled to fit in
the imageable width.

import java.awt.*;
import java.awt.event.*;
import java.awt.image.*;
import java.awt.print.*;
import java.io.*;
import javax.imageio.*;
import javax.swing.*;

public class test extends JPanel implements Printable {
     BufferedImage bi;
     int w,h;
     volatile static PageFormat pf;

     public test() {
         try {
             bi = ImageIO.read(new File("kittens.jpg"));
             w = bi.getWidth();
             h = bi.getHeight();
             setPreferredSize(new Dimension(w,h));
         } catch (IOException ioe) {
             ioe.printStackTrace();
         }
     }

     void render(Graphics g, boolean printerFlag) {
         if (printerFlag)
             g.drawImage(bi,
              (int)pf.getImageableX(),
              (int)pf.getImageableY(),
              (int)pf.getImageableWidth(),
              (int)(pf.getImageableWidth()/1.333),null);
         else
             g.drawImage(bi,0,0,w,h,null);
     }

     public void paintComponent(Graphics g) {
         render(g, false);
     }

     public int print(Graphics g, PageFormat pageFormat, int pageIndex) {
         int retcod = Printable.PAGE_EXISTS;
         if (pageIndex == 0) {
             render(g, true);
         } else
             retcod = Printable.NO_SUCH_PAGE;

         return retcod;
     }

     public static void main(String[] args) {
         EventQueue.invokeLater(new Runnable() {
             public void run() {
                 JFrame f = new JFrame("test");
                 f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
                 final test t = new test();
                 f.add(t,BorderLayout.CENTER);
                 JButton b = new JButton("Print");
                 b.addActionListener(new ActionListener() {
                     public void actionPerformed(ActionEvent ae) {
                         PrinterJob pj = PrinterJob.getPrinterJob();
                         pf = pj.defaultPage();
                         pj.setPrintable(t);
                         PageFormat pf = pj.pageDialog(pj.defaultPage());
                         try {
                             pj.print();
                         } catch (PrinterException pe) {
                             pe.printStackTrace();
                         }
                     }
                 });
                 f.add(b,BorderLayout.SOUTH);
                 f.pack();
                 f.setVisible(true);
             }
         });
     }
}

--

Knute Johnson
email s/nospam/knute/

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