javaweb pdf流转jpg流怎么操作?

发布网友发布时间：2022-05-01 03:41

共1个回答

热心网友时间：2022-06-24 03:07

package pdf;
import java.awt.Image;
import java.awt.Rectangle;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.RandomAccessFile;
import java.nio.ByteBuffer;
import java.nio.channels.FileChannel;
import javax.swing.SwingUtilities;
import com.sun.image.codec.jpeg.JPEGCodec;
import com.sun.image.codec.jpeg.JPEGEncodeParam;
import com.sun.image.codec.jpeg.JPEGImageEncoder;
import com.sun.pdfview.PDFFile;
import com.sun.pdfview.PDFPage;
public class PdfToJpg {
public static void setup() throws IOException {
// 加载一个pdf从一个字节缓冲区
File file = new File("D:\\yangliu\\test.pdf");
RandomAccessFile raf = new RandomAccessFile(file, "r");
FileChannel channel = raf.getChannel();
ByteBuffer buf = channel.map(FileChannel.MapMode.READ_ONLY, 0,
channel.size());
PDFFile pdffile = new PDFFile(buf);
System.out.println("页数：" + pdffile.getNumPages());
String getPdfFilePath = System.getProperty("user.dir") + "\\pdfPicFile";
System.out.println("getPdfFilePath is :" + getPdfFilePath);

for (int i = 1; i < pdffile.getNumPages(); i++) {
// 画第一页到一个图像
PDFPage page = pdffile.getPage(i);
// 获得宽度和高度的文件在默认的变焦
Rectangle rect = new Rectangle(0, 0, (int) page.getBBox()
.getWidth(), (int) page.getBBox().getHeight());
// 生成图像
Image img = page.getImage(rect.width, rect.height, rect, null,
true, true);
BufferedImage tag = new BufferedImage(rect.width, rect.height,
BufferedImage.TYPE_INT_RGB);
tag.getGraphics().drawImage(img, 0, 0, rect.width, rect.height,
null);
// 输出到文件流
FileOutputStream out = new FileOutputStream(getPdfFilePath + "\\"
+ i + ".jpg");
System.out.println("成功保存图片到："+getPdfFilePath+"\\"+i+".jpg");

JPEGImageEncoder encoder = JPEGCodec.createJPEGEncoder(out);
JPEGEncodeParam param = encoder.getDefaultJPEGEncodeParam(tag);
param.setQuality(1f, false); //1f是提高生成的图片质量
encoder.setJPEGEncodeParam(param);
encoder.encode(tag); // JPEG编码
out.close();
}
}

public static void main(final String[] args){
SwingUtilities.invokeLater(new Runnable() {
public void run() {
try {
PdfToJpg.setup();
} catch (IOException e) {
e.printStackTrace();
}
}
});
}
}追问跟网上一个答案，如果可以我还来知道做什么