java设置图像的分辨率和打印尺寸
我编写了一个程序,该程序生成一个BufferedImage以显示在屏幕上,然后打印出来。部分图像包含1像素宽的网格线。也就是说,这条线是1个像素,线之间有大约10个像素。由于屏幕分辨率的原因,图像显示得比这更大,每行有几个像素。我想绘制它更小,但是当我缩放图像(通过使用Image.getScaledInstance或Graphics2D.scale)时,我失去了大量的细节。java设置图像的分辨率和打印尺寸
我想打印图像,并处理相同的问题。在这种情况下,我使用此代码来设置分辨率:
HashPrintRequestAttributeSet set = new HashPrintRequestAttributeSet();
PrinterResolution pr = new PrinterResolution(250, 250, ResolutionSyntax.DPI);
set.add(pr);
job.print(set);
它可以使图像变小而不会丢失细节。但问题是,图像在相同的边界被切断,就好像我没有设置分辨率一样。我也很困惑,因为我希望更多的DPI能够制作出更小的图像,但是它正在以另一种方式发挥作用。
我在eclipse上使用Windows 7上的Java 1.6。
这听起来像你的问题是,你正在使网格线BufferedImage的一部分,并且它缩放时看起来不好。为什么不使用drawLine()在绘制图像后生成网格?
您可以使用以下任一方式来提高缩放质量。我相信BiCubic会有更好的效果,但比BILINEAR慢。
g2d.setRenderingHint(RenderingHints.KEY_INTERPOLATION, RenderingHints.VALUE_INTERPOLATION_BICUBIC);
g2d.setRenderingHint(RenderingHints.KEY_INTERPOLATION, RenderingHints.VALUE_INTERPOLATION_BILINEAR);
我也不会使用Image.getScaledInstance(),因为它非常慢。由于我在类似的问题上挣扎,我不确定印刷。
关于在页面边界上被截断的图像,您是否检查过图形的剪辑区域?我的意思是尝试:
System.out.println(graphics.getClipBounds());
并确保它被正确设置。
使用Java转换具有尺寸的图像的代码并打印转换后的图像。
类别: ConvertImageWithDimensionsAndPrint.java
package com.test.convert;
import java.awt.Graphics2D;
import java.awt.image.BufferedImage;
import java.io.File;
import javax.imageio.ImageIO;
public class ConvertImageWithDimensionsAndPrint {
private static final int IMAGE_WIDTH = 800;
private static final int IMAGE_HEIGHT = 1000;
public static void main(String[] args) {
try {
String sourceDir = "C:/Images/04-Request-Headers_1.png";
File sourceFile = new File(sourceDir);
String destinationDir = "C:/Images/ConvertedImages/";//Converted images save here
File destinationFile = new File(destinationDir);
if (!destinationFile.exists()) {
destinationFile.mkdir();
}
if (sourceFile.exists()) {
String fileName = sourceFile.getName().replace(".png", "");
BufferedImage bufferedImage = ImageIO.read(sourceFile);
int type = bufferedImage.getType() == 0 ? BufferedImage.TYPE_INT_ARGB : bufferedImage.getType();
BufferedImage resizedImage = new BufferedImage(IMAGE_WIDTH, IMAGE_HEIGHT, type);
Graphics2D graphics2d = resizedImage.createGraphics();
graphics2d.drawImage(bufferedImage, 0, 0, IMAGE_WIDTH, IMAGE_HEIGHT, null);//resize goes here
graphics2d.dispose();
ImageIO.write(resizedImage, "png", new File(destinationDir + fileName +".png"));
int oldImageWidth = bufferedImage.getWidth();
int oldImageHeight = bufferedImage.getHeight();
System.out.println(sourceFile.getName() +" OldFile with Dimensions: "+ oldImageWidth +"x"+ oldImageHeight);
System.out.println(sourceFile.getName() +" ConvertedFile converted with Dimensions: "+ IMAGE_WIDTH +"x"+ IMAGE_HEIGHT);
//Print the image file
PrintActionListener printActionListener = new PrintActionListener(resizedImage);
printActionListener.run();
} else {
System.err.println(destinationFile.getName() +" File not exists");
}
} catch (Exception e) {
e.printStackTrace();
}
}
}
PrintActionListener.java的Reference
package com.test.convert;
import java.awt.Graphics;
import java.awt.image.BufferedImage;
import java.awt.print.PageFormat;
import java.awt.print.Printable;
import java.awt.print.PrinterException;
import java.awt.print.PrinterJob;
public class PrintActionListener implements Runnable {
private BufferedImage image;
public PrintActionListener(BufferedImage image) {
this.image = image;
}
@Override
public void run() {
PrinterJob printJob = PrinterJob.getPrinterJob();
printJob.setPrintable(new ImagePrintable(printJob, image));
if (printJob.printDialog()) {
try {
printJob.print();
} catch (PrinterException prt) {
prt.printStackTrace();
}
}
}
public class ImagePrintable implements Printable {
private double x, y, width;
private int orientation;
private BufferedImage image;
public ImagePrintable(PrinterJob printJob, BufferedImage image) {
PageFormat pageFormat = printJob.defaultPage();
this.x = pageFormat.getImageableX();
this.y = pageFormat.getImageableY();
this.width = pageFormat.getImageableWidth();
this.orientation = pageFormat.getOrientation();
this.image = image;
}
@Override
public int print(Graphics g, PageFormat pageFormat, int pageIndex) throws PrinterException {
if (pageIndex == 0) {
int pWidth = 0;
int pHeight = 0;
if (orientation == PageFormat.PORTRAIT) {
pWidth = (int) Math.min(width, (double) image.getWidth());
pHeight = pWidth * image.getHeight()/image.getWidth();
} else {
pHeight = (int) Math.min(width, (double) image.getHeight());
pWidth = pHeight * image.getWidth()/image.getHeight();
}
g.drawImage(image, (int) x, (int) y, pWidth, pHeight, null);
return PAGE_EXISTS;
} else {
return NO_SUCH_PAGE;
}
}
}
}
输出:
04-Request-Headers_1.png OldFile with Dimensions: 1224x1584
04-Request-Headers_1.png ConvertedFile converted with Dimensions: 800x1000
一个图像的转换后打印窗口将开放用于打印转换后的图像。窗口显示如下,从选择打印机名称下拉框并点击确定按钮。
我有同样的问题。这是我的解决方案。
首先更改打印作业的分辨率...
PrinterJob job = PrinterJob.getPrinterJob();
// Create the paper size of our preference
double cmPx300 = 300.0/2.54;
Paper paper = new Paper();
paper.setSize(21.3 * cmPx300, 29.7 * cmPx300);
paper.setImageableArea(0, 0, 21.3 * cmPx300, 29.7 * cmPx300);
PageFormat format = new PageFormat();
format.setPaper(paper);
// Assign a new print renderer and the paper size of our choice !
job.setPrintable(new PrintReport(), format);
if (job.printDialog()) {
try {
HashPrintRequestAttributeSet set = new HashPrintRequestAttributeSet();
PrinterResolution pr = new PrinterResolution((int) (dpi), (int) (dpi), ResolutionSyntax.DPI);
set.add(pr);
job.setJobName("Jobname");
job.print(set);
} catch (PrinterException e) {
}
}
现在你能得到你的喜欢到喜欢这个新的高分辨率纸的一切!
public class PrintReport implements Printable {
@Override
public int print(Graphics g, PageFormat pf, int page) throws PrinterException {
// Convert pixels to cm to lay yor page easy on the paper...
double cmPx = dpi/2.54;
Graphics2D g2 = (Graphics2D) g;
int totalPages = 2; // calculate the total pages you have...
if (page < totalPages) {
// Draw Page Header
try {
BufferedImage image = ImageIO.read(ClassLoader.getSystemResource(imgFolder + "largeImage.png"));
g2.drawImage(image.getScaledInstance((int) (4.8 * cmPx), -1, BufferedImage.SCALE_SMOOTH), (int) (cmPx),
(int) (cmPx), null);
} catch (IOException e) {
}
// Draw your page as you like...
// End of Page
return PAGE_EXISTS;
} else {
return NO_SUCH_PAGE;
}
}
我不确定你的建议。也许我应该缩放图像,然后画线?我不想缩放图像或线条,而我的屏幕和打印机都有大量的DPI来显示所有细节。我提到了线条,但也有很多很小的(10像素方块)图标,如果我缩放1/2,它们就会变得模糊不清。这对我来说没有意义,这很不容易(大概很简单,我只是不知道该怎么做)。 – Ingrid 2010-06-17 01:02:31
Printable提供了一个Graphics2D对象:'public int print(Graphics g,PageFormat pf,int page)'。不要将您的页面渲染为一个巨大的像素化图像,而应将其渲染为矢量图形调用:例如,多个'g.drawLine()'和'g.drawImage()'调用。 – Justin 2010-06-17 11:43:52
我会试试看看它的外观。如果我理解正确,但这只会让不那么细致的显示效果更好。有没有办法显示和打印所有的细节? – Ingrid 2010-06-17 18:38:34