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使用JMagick为图片打水印

Posted by eDWARD at 22:59

1. 为了保护图片的版权，我们经常需要在上传的照片上打上版权信息或图标，下面介绍利用JMagick在图片上做标记。引入JMagick需要的类库：

   import java.awt.Dimension;
   import java.awt.Rectangle;
   
   import magick.CompositeOperator;
   import magick.ImageInfo;
   import magick.MagickException;
   import magick.MagickImage;
   

2. 下面介绍如何使用JMagick做标记：

   public static void mask(String logoPath, String srcPathName, String destPathName, int location, int scale) throws MagickException {
     int width = getWidth(srcPathName);
     int height = getHeight(srcPathName);
     int x = 0, y = 0;
     int w, h;
     w = scale * 70 / 100;
     h = scale * 65 / 100;
     boolean lc = true;
     if (width < height) {
       switch (location) {
         case 0:
           lc = false;
           break;
         case 1:
           x = width / 4 - w;
           y = height / 8 - h / 2;
           break;
         case 2:
           x = width / 2 - w;
           y = height / 8 - h / 2;
           break;
         case 3:
           x = width * 3 / 4 - w;
           y = height / 8 - h / 2;
           break;
         case 4:
           x = width / 4 - w;
           y = height / 2 - h / 2;
           break;
         case 5:
           x = width / 2 - w;
           y = height / 2 - h / 2;
           break;
         case 6:
           x = width * 3 / 4 - w;
           y = height / 2 - h / 2;
           break;
         case 7:
           x = width / 4 - w;
           y = height * 7 / 8 - h / 2;
           break;
         case 8:
           x = width / 2 - w;
           y = height * 7 / 8 - h / 2;
           break;
         case 9:
           x = width * 3 / 4 - w;
           y = height * 7 / 8 - h / 2;
           break;
       }
     } else {
       switch (location) {
         case 0:
           lc = false;
           break;
         case 1:
           x = width / 7 - w;
           y = height / 6 - h / 2;
           break;
         case 2:
           x = width / 2 - w;
           y = height / 6 - h / 2;
           break;
         case 3:
           x = width * 6 / 7 - w;
           y = height / 6 - h / 2;
           break;
         case 4:
           x = width / 7 - w;
           y = height / 2 - h / 2;
           break;
         case 5:
           x = width / 2 - w;
           y = height / 2 - h / 2;
           break;
         case 6:
           x = width * 6 / 7 - w;
           y = height / 2 - h / 2;
           break;
         case 7:
           x = width / 7 - w;
           y = height * 5 / 6 - h / 2;
           break;
         case 8:
           x = width / 2 - w;
           y = height * 5 / 6 - h / 2;
           break;
         case 9:
           x = width * 6 / 7 - w;
           y = height * 5 / 6 - h / 2;
           break;
       }
     }
     if (x < 10) {
       x = 10;
     }
     if (x + w * 2 + 10 > width) {
       x = width - w * 2 - 10;
     }
     if (y < 10) {
       y = 10;
     }
     if (y + h + 10 > height) {
       y = height - h - 10;
     }
     if (lc) {
       ImageInfo info = new ImageInfo();
       MagickImage image = null;
       MagickImage mask = null;
       MagickImage dest = null;
       try {
         image = new MagickImage(new ImageInfo(srcPathName + “[0]“));
         mask = new MagickImage(new ImageInfo(logoPath));
         image.setFileName(destPathName);
         image.writeImage(info);
         dest = new MagickImage(new ImageInfo(destPathName));
         dest.compositeImage(CompositeOperator.AtopCompositeOp, mask, x, y);
         dest.setFileName(destPathName);
         dest.writeImage(info);
       } finally {
         if (image != null) {
           image.destroyImages();
         }
         if (mask != null) {
           mask.destroyImages();
         }
         if (dest != null) {
           dest.destroyImages();
         }
       }
     }
   }
   

   getWidth(String src) & getHeight(String src)

   public static int getWidth(String src) throws MagickException {
     MagickImage magImage = null;
     try {
       ImageInfo info = new ImageInfo(src + “[0]“);
       magImage = new MagickImage(info);
       Dimension imageDim = magImage.getDimension();
       return imageDim.width;
     } finally {
       if (magImage != null) {
         magImage.destroyImages();
       }
     }
   }
   
   public static int getHeight(String src) throws MagickException {
     MagickImage magImage = null;
     try {
       ImageInfo info = new ImageInfo(src + “[0]“);
       magImage = new MagickImage(info);
       Dimension imageDim = magImage.getDimension();
       return imageDim.height;
     } finally {
       if (magImage != null) {
         magImage.destroyImages();
       }
     }
   }
   

Filed In 学习路上 | Study | Tags: Java, JMagick, 图片, 打水印 | Add a Comment »

使用JMagick压缩图片大小尺寸

Posted by eDWARD at 22:25

1. 我们经常需要实现图片上传的功能，但是光是上传图片可能还是远远不够的，我们必须对我们上传的图片进行处理，改变大小等等。JMagick是ImageMagick提供的一套使用Java调用ImageMagick的API接口，功能非常强大，下面介绍如果使用这个API处理图片的大小。引入JMagick需要的类库：

   import magick.ImageInfo;
   import magick.MagickException;
   import magick.MagickImage;
   

2. 我们需要把图片保存为两个尺寸，这里要提前定义两种常量：

   public static String SIZENAME_LARGE = “large”;
   public static String SIZENAME_SMALL = “small”;
   

3. 下面介绍如何使用JMagick，里面用到的ImageUtil稍后会介绍，FileUtil是操作文件的工具类，这里就暂时不介绍了：

   MagickImage source = ImageUtil.getMagickImage(”image file name”);
   Map map = processHead(source);
   System.out.ptineln(map.get(SIZENAME_LARGE));
   System.out.ptineln(map.get(SIZENAME_SMALL));
   

   ImageUtil.getMagickImage(byte[] byte)

   public static MagickImage getMagickImage(byte[] byte) throws MagickException {
     ImageInfo info = new ImageInfo();
     return new MagickImage(info, byte);
   }
   

   processHead(MagickImage source)

   private Map processHead(MagickImage source) throws Exception {
     MagickImage regulate = null;
     MagickImage large = null;
     MagickImage small = null;
   
     //保存图片的临时目录
     String tempPath = “….”;
     //随即生成一个文件名，真是情况生成的目录可能更复杂
     String fn = FileUtil.getInstance().getRandName();
     String largeName = SIZENAME_LARGE + “_” + fn + “.jpg”;
     String smallName = SIZENAME_SMALL + “_” + fn + “.jpg”;
   
     try {
       //改变图片大小
       regulate = ImageUtil.regulate(source);
       large = ImageUtil.resizePhoto(regulate, tempPath + largeName, 500, 750);
       small = ImageUtil.resizePhoto(large, tempPath + smallName, 90, 120);
       byte[] largeByte = large.imageToBlob(new ImageInfo());
       byte[] smallByte = small.imageToBlob(new ImageInfo());
   
       //保存图片的目录
       String uploadPath = “….”;
       //写文件到目录
       FileUtil.getInstance().writeFile(uploadPath + largeName, largeByte);
       FileUtil.getInstance().writeFile(uploadPath + smallName, smallByte);
   
       //返回图片地址
       Map map = new HashMap();
       map.put(SIZENAME_LARGE, “/” + dir + largeName);
       map.put(SIZENAME_SMALL, “/” + dir + smallName);
       return map;
     } catch (Exception e) {
       throw e;
     } finally {
       if (small != null)
         small.destroyImages();
       if (large != null)
         large.destroyImages();
       if (regulate != null)
         regulate.destroyImages();
       }
     }
   }
   

   ImageUtil.regulate(MagickImage source)

   public static MagickImage regulate(MagickImage source) throws MagickException {
     int width = (int) source.getDimension().getWidth();
     int height = (int) source.getDimension().getHeight();
     if ((height + 0.0) / width > 1.5) {
       MagickImage image = null;
       MagickImage scaled = null;
       try {
         int newHeight = (int) Math.round(width * 1.5);
         Rectangle rect = new Rectangle(0, (height - newHeight) / 2, width, newHeight);
         ImageInfo info = null;
         info = new ImageInfo();
   
         scaled = source.cropImage(rect);
         return scaled;
       } finally {
         if (source != null) {
           source.destroyImages();
         }
       }
     } else {
       return source;
     }
   }
   

   ImageUtil.resizePhoto(MagickImage source, String destPathName, int maxWidth, int maxHeight)

   public static MagickImage resizePhotoStep(MagickImage source, String destPathName, int maxWidth, int maxHeight) throws MagickException {
     int width = 0;
     int height = 0;
     boolean change = true;
     width = (int) source.getDimension().getWidth();
     height = (int) source.getDimension().getHeight();
     if (maxWidth > width && maxHeight > height) {
       change = false;
     } else {
       if (width > 0 && height > 0) {
         if (height / width > maxHeight / maxWidth) {
           width = width * maxHeight / height;
           height = maxHeight;
         } else {
           height = height * maxWidth / width;
           width = maxWidth;
         }
       }
     }
   
     MagickImage scaled = null;
     scaled = source.scaleImage(width, height);
     scaled.setFileName(destPathName);
     return scaled;
   }
   

   下次介绍打标签的方法。

Filed In 学习路上 | Study | Tags: Java, JMagick, 修改尺寸, 压缩图片 | Add a Comment »

安装ImageMagick和JMagick的注意事项

Posted by eDWARD at 17:28

好久没写安装笔记了，因为好久没有摸过Linux了…… 由于自己用JMagick写了一个图像处理引擎，所以需要在服务器上安装这两个软件。

安装ImageMagick和JMagick

1. 把ImageMagick-6.3.2-9.tar.gz下载到 /usr/local/src 下，然后解压缩

   shell> cd /usr/local/src
   shell> tar -zxvf ImageMagick-6.3.2-9.tar.gz
   shell> cd ImageMagick-6.3.2
   shell> ./configure
   shell> make
   shell> make install
   shell> make check
   shell> cd ..
   

   看看测试结果，总共有六百多个测试。。。。这里有一个重要问题，很多服务器虽然都安装了必须的zlib、freetype、libpng和jpeg-6b，但是在这里安装程序根本找不到他们，尤其是jpeg-6b，我们开始就忽略了这点，导致JBoss在处理jpg文件时直接灸崩溃了，真是够烂的，想比之下Resin就做的很好，很友善的提示了个错误，虽然跟没提示差不多吧：（ 无奈，只要重新下载jpeg-6b的src，安装完成后Resin下一切正常，JBoss继续崩溃……

2. 把JMagick-6.2.6-0.tar.gz下载到 /usr/local/src 下，然后解压缩到

   shell> cd /usr/local/src
   shell> tar -zxvf JMagick-6.2.6-0.tar.gz
   shell> cd JMagick-6.2.6
   shell> ./configure –with-java-home=/opt/java
   shell> make
   shell> make install
   shell> make test
   shell> cd ..
   

   最后的test是运行JMagick自带的java程序，目的是测试安装后的JMagick是否可用

注意事项

1. 调用程序的时候出现类似“ no JMagick in java.library.path”这样的错误，这个主要是因为java虚拟机找不到“libJMagick.so”，解决办法就是吧“libJMagick.so”这个文件拷到 “jre/lib/i386”目录下就可以了。
2. 把“jmagick.jar”这个文件拷到您应用的“WEB-INF/lib”目录下。
3. 在代码中使用前设置：System.setProperty(”jmagick.systemclassloader”,”no”)；或者直接加载在启动项上：-Djmagick.systemclassloader=no；或者在Resin配置文件中加入配置：< system-property systemclassloader=”no”/>；

Filed In 学习路上 | Study | Tags: ImageMagick, JMagick, 安装笔记 | 4 Comments »