| /** * 将pdf转成img */ public static void changePdfToImg() { try { File file = new File("E:\\test\\baseInfo_2.pdf"); RandomAccessFile raf = new RandomAccessFile(file, "r"); FileChannel channel = raf.getChannel(); MappedByteBuffer buf = channel.map(FileChannel.MapMode.READ_ONLY, 0, channel.size()); PDFFile pdffile = new PDFFile(buf); for (int i = 1; i <= pdffile.getNumPages(); i++) { PDFPage page = pdffile.getPage(i); Rectangle rect = new Rectangle(0, 0, ((int) page.getBBox().getWidth()), ((int) page.getBBox().getHeight())); Image img = page.getImage(rect.width, rect.height, rect, null, // null for the ImageObserver true, // fill background with white true // block until drawing is done ); BufferedImage tag = new BufferedImage(rect.width, rect.height, BufferedImage.TYPE_INT_RGB); tag.getGraphics().drawImage(img, 0, 0, rect.width, rect.height, null); FileOutputStream out = new FileOutputStream("E:\\test\\img\\" + i + ".jpg"); // 输出到文件流 JPEGImageEncoder encoder = JPEGCodec.createJPEGEncoder(out); JPEGEncodeParam param2 = encoder.getDefaultJPEGEncodeParam(tag); param2.setQuality(1f, false);// 1f是提高生成的图片质量 encoder.setJPEGEncodeParam(param2); encoder.encode(tag); // JPEG编码 out.close(); } channel.close(); raf.close(); unmap(buf);//如果要在转图片之后删除pdf，就必须要这个关闭流和清空缓冲的方法 } catch (FileNotFoundException e) { e.printStackTrace(); } catch (IOException e) { e.printStackTrace(); } } /** * 清空缓冲 * @param buffer */ public static void unmap(final Object buffer) { AccessController.doPrivileged(new PrivilegedAction() { public Object run() { try { Method getCleanerMethod = buffer.getClass().getMethod("cleaner", new Class[0]); getCleanerMethod.setAccessible(true); sun.misc.Cleaner cleaner = (sun.misc.Cleaner) getCleanerMethod.invoke(buffer, new Object[0]); cleaner.clean(); } catch (Exception e) { e.printStackTrace(); } return null; } }); } |
