Java-很深我只知其一-BufferedImage对象绘制图片（P图）

本文主要是介绍Java-很深我只知其一-BufferedImage对象绘制图片（P图），希望对大家解决编程问题提供一定的参考价值，需要的开发者们随着小编来一起学习吧！

BufferedImage对象绘制图片（P图）

• maven依赖

<dependency><groupId>commons-io</groupId><artifactId>commons-io</artifactId><version>2.4</version>
</dependency>

• 图片中加入简单的文字，并转换为Bsae64

        String result;try {BufferedImage buffImg = ImageIO.read(new File("图片绝对路径"));Graphics2D g = (Graphics2D)buffImg.getGraphics();//得到画笔对象//设置字体，大小g.setColor(Color.BLACK);g.setFont(new Font("黑体", Font.BOLD, 37));LocalDate now = LocalDate.now();g.drawString(String.valueOf(now.getYear()), 11, 11);g.drawString(String.valueOf(now.getMonthValue()), 111, 111);g.drawString(String.valueOf(now.getDayOfMonth()), 1111, 1111);ImageIO.write(buffImg, "PNG", new File("写出后的文件路径"));BASE64Encoder encoder = new BASE64Encoder();// 文件转码result = encoder.encode(getBytes(finalPath)).replaceAll("\r\n", "");g.dispose();} catch (Exception e) {throw new MyException("文件流转化出错");}

•  旋转与缩放

/***旋转与缩放* degree：旋转角度* shrinkW，shrinkH：缩放比例 原始值为1（值越大图片缩小）* moveX，moveY：图片在画布中的x，y位置* @param bufferedimage* @param degree* @return*/private BufferedImage rotateImage(final BufferedImage bufferedimage,final int degree,final double shrinkW,final double shrinkH,final int moveX,final int moveY) {int w = (int)Math.round(bufferedimage.getWidth()*shrinkW);int h =  (int)Math.round(bufferedimage.getHeight()*shrinkH);int type = bufferedimage.getColorModel().getTransparency();BufferedImage img;Graphics2D graphics2d;(graphics2d = (img = new BufferedImage(w, h, type)).createGraphics()).setRenderingHint(RenderingHints.KEY_INTERPOLATION,RenderingHints.VALUE_INTERPOLATION_BILINEAR);graphics2d.rotate(Math.toRadians(degree), w / 2, h / 2);graphics2d.drawImage(bufferedimage, moveX,moveY, null);graphics2d.dispose();return img;}

• 将文件对象转换为PDF

/*** 要加入PDF文件的全限定名* @param imgFilePath* 转换为PDF后文件的放置位置* @param pdfFilePath* //调节图片在PDF中的尺寸* @param ratio1* @param ratio2* @param ratio3* @param ratio4* 文件在PDF中的X,Y轴坐标* @param absoluteX* @param absoluteY* @throws Exception*/
public void image2pdf(String imgFilePath, String pdfFilePath, Float ratio1, Float ratio2, Float ratio3, Float ratio4, Float absoluteX, Float absoluteY) throws Exception {com.itextpdf.text.Document document = new com.itextpdf.text.Document();FileOutputStream fos = null;fos = new FileOutputStream(pdfFilePath);PdfWriter.getInstance(document, fos);//输出为A4纸张document.setPageSize(PageSize.A4);document.open();com.itextpdf.text.Image image = com.itextpdf.text.Image.getInstance(imgFilePath);//调节图片在PDF中的尺寸float imageHeight = image.getScaledHeight() / ratio1 * ratio2;float imageWidth = image.getScaledWidth() / ratio3 * ratio4;image.setAlignment(com.itextpdf.text.Image.ALIGN_CENTER);// 设置图片的绝对位置image.setAbsolutePosition(absoluteX, absoluteY);image.scaleAbsolute(imageWidth, imageHeight);// 插入一个图片document.add(image);document.close();fos.flush();fos.close();}

 

/*** 获得指定文件的byte数组*/private static byte[] getBytes(String filePath){byte[] buffer = null;try {File file = new File(filePath);FileInputStream fis = new FileInputStream(file);ByteArrayOutputStream bos = new ByteArrayOutputStream(8192);byte[] b = new byte[8192];int n;while ((n = fis.read(b)) != -1) {bos.write(b, 0, n);}fis.close();bos.close();buffer = bos.toByteArray();} catch (FileNotFoundException e) {e.printStackTrace();} catch (IOException e) {e.printStackTrace();}return buffer;}

 

这篇关于Java-很深我只知其一-BufferedImage对象绘制图片（P图）的文章就介绍到这儿，希望我们推荐的文章对编程师们有所帮助！

---