集思广益 JSP图片处理能力

Question

本帖最后由 kokobox 于 2009-03-20 14:17:39 编辑

Answer 1

网页中实现这些功能不现实吗！ JSP不能实现这些功能吗？ 高手们呢，

Answer 2

可以在JSP网页中嵌入第三方插件啊。

Answer 3

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Answer 4

<a href="http://www.baidu.com">what is </a>

Answer 5

如果在客户端做，那是js的问题
如果在后台做，那是java的问题
总之，和jsp关系不大

Answer 6

图片处理和JSP没什么关系，Java提供了JAI开发包处理图片，当然还有很多开源的实现。
至于对图片进行操作，一般都是自己实现，主要是操作BufferedImage来达到目的。

Answer 7

JAVA核心技术第二卷里面有讲对图像的处理，你说的这些我记得好像基本上都讲到了。

Answer 8

首先你先用javax.imageio.imageReader类将用户上传的图片读取到内存中生成BufferImage对象，此对象能够对图像像素矩阵进行操作， 
转换成黑白图片以及白色显示为透明状态都有常用的算法，其实就是操作图片的像素点 
处理完后再通过imageWriter类将图片存为图片文件，在页面上用<img>标签显示就行了 
具体的函数方法去参考api 
jdk 里面有对jepg 和 bmp格式图像读取的类 

Answer 9

Class.forName("org.gjt.mm.mysql.Driver").newInstance(); 
String url ="jdbc:mysql://localhost:3306/test?user=root&password=eastsoftweb";
Connection conn= DriverManager.getConnection(url); 
java.io.File file = new File("d:/temp/1.jpg");
 FileInputStream is=new FileInputStream(file);
 PreparedStatement stmt = conn.prepareStatement(
          "INSERT INTO imagetable (nid,image)" +
"VALUES (?, ?)");  //预编译SQL语句
 stmt.setInt(1, 1);
 stmt.setBinaryStream(2, is,(int)file.length());
 stmt.executeUpdate();
 stmt.close();
 is.close();
 out.println("update end");
//＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝将文件写入到数据库的大字段中end＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝
*/
/*
//＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝ 二、jsp显示服务器硬盘图片示例 begin＝＝＝＝＝＝＝＝＝＝＝＝＝＝FileInputStream is=new FileInputStream("d:/temp/1.JPG");
response.reset();
response.setContentType("image/jpeg");         
ServletOutputStream sos = response.getOutputStream();      
byte[] buffer = new byte[1024];
int len=0;
while((len=is.read(buffer))>0){
  sos.write(buffer,0,len); 
}  
  sos.flush();      
  sos.close(); 

Answer 10

Class.forName("org.gjt.mm.mysql.Driver").newInstance(); 
String url ="jdbc:mysql://localhost:3306/test?user=root&password=eastsoftweb";
Connection conn= DriverManager.getConnection(url); 
java.io.File file = new File("d:/temp/db.jpg");
FileOutputStream os=new FileOutputStream(file);
Statement stmt=conn.createStatement(ResultSet.TYPE_SCROLL_SENSITIVE,ResultSet.CONCUR_READ_ONLY); 
ResultSet rs=stmt.executeQuery("select nid,image from imagetable where nid=1");
rs.next();
byte[] buffer=rs.getBytes(2);
stmt.close();
os.write(buffer);
os.flush();
os.close();
out.println("query end");//网页上显示
response.reset();
response.setContentType("image/jpeg");         
ServletOutputStream sos = response.getOutputStream();      
sos.write(buffer);
sos.flush();      
sos.close(); 
//＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝将数据库的大字段图片还原到本地,并在网页上显示end＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝
 
/*
//＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝四、生成缩略图begin＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝
File file = new File("d:/temp/1.JPG"); 
String newurl="d:/temp/2.jpg";  //新的缩略图保存地址
Image src = javax.imageio.ImageIO.read(file);                     //构造Image对象
float tagsize=200;
int old_w=src.getWidth(null);                                     //得到源图宽
int old_h=src.getHeight(null);   
int new_w=0;
int new_h=0;                            //得到源图长
int tempsize;
float tempdouble; 
if(old_w>old_h){
 tempdouble=old_w/tagsize;
}else{
 tempdouble=old_h/tagsize;
}
new_w=Math.round(old_w/tempdouble);
new_h=Math.round(old_h/tempdouble);//计算新图长宽
BufferedImage tag = new BufferedImage(new_w,new_h,BufferedImage.TYPE_INT_RGB);
tag.getGraphics().drawImage(src,0,0,new_w,new_h,null);       //绘制缩小后的图
FileOutputStream newimage=new FileOutputStream(newurl);          //输出到文件流
JPEGImageEncoder encoder = JPEGCodec.createJPEGEncoder(newimage);       
encoder.encode(tag);                                               //近JPEG编码
newimage.close(); 

Answer 11

代码繁多.就不好贴出来了 
JAVA2核心技术卷二 第七章高级AWT里面都有详细的介绍

Answer 12

 
 jsp------图片？？？？

Answer 13

我看到过一些关于Java编辑图片的例子好像用到了Java.swing.*中的类。其实Java世具备处理图片的能力的

Answer 14

/// <summary>
        /// 图片加水印
        /// </summary>
        /// <param name="filepath">图片路径</param>
        /// <returns>BitMap</returns>
        private static Bitmap AddWord(string filepath){
            var bm=new Bitmap(filepath);
            using(Graphics g=Graphics.FromImage(bm)){
                g.DrawString("", new System.Drawing.Font("隶书", 36), new System.Drawing.SolidBrush(System.Drawing.Color.White), bm.Width / 10 - 50, bm.Height / 10 - 20);
            }
            return bm;
        }

Answer 15

        /// <summary>
        /// 生成缩微图
        /// </summary>
        /// <param name="filepath">路径</param>
        /// <param name="thumbWi">缩微图宽</param>
        /// <param name="thumbHi">缩微图高</param>
        /// <param name="maintainAspect">长宽是否重置</param>
        /// <param name="Water">是否带水印,true 带水印,flase 不带水印</param>
        /// <returns>Bitmap</returns>
        private static Bitmap CreateThumbnail
            (string filepath,int thumbWi,int thumbHi,bool maintainAspect,bool Water){
            var source=new Bitmap(filepath);
            if(Water){
                source.Dispose();
                source=AddWord(filepath);
            }
            Bitmap ret=null;
            try{
                int wi,hi;                wi=thumbWi;
                hi=thumbHi;                if(maintainAspect){
                    if(source.Width
                        >source.Height){
                        wi=thumbWi;
                        hi=(int)(source.Height*((decimal)thumbWi/source.Width));
                    }
                    else{
                        hi=thumbHi;
                        wi=(int)(source.Width*((decimal)thumbHi/source.Height));
                    }
                }
                ret=new Bitmap(wi,hi);
                using(Graphics g=Graphics.FromImage(ret)){
                    g.InterpolationMode=InterpolationMode.HighQualityBicubic;
                    g.FillRectangle(Brushes.White,0,0,wi,hi);
                    g.DrawImage(source,0,0,wi,hi);
                }
                source.Dispose();
            }
            catch{
                ret=null;
            }            return ret;
        }        /// <summary>
        /// 生成缩微图
        /// </summary>
        /// <param name="filepath">路径</param>
        /// <param name="word">水印内容</param>
        /// <param name="fontsize">字体大小</param>
        /// <param name="color">字体颜色</param>
        /// <param name="thumbWi">缩微图宽</param>
        /// <param name="thumbHi">缩微图高</param>
        /// <param name="maintainAspect">长宽知否重置</param>
        /// <param name="Water">是否带水印</param>
        /// <returns></returns>
        private static Bitmap CreateThumbnail
            (
            string filepath,string word,int fontsize,Color color,int thumbWi,int thumbHi,bool maintainAspect,
            bool Water){
            var source=new Bitmap(filepath);
            if(Water){
                source.Dispose();
                source=AddWord(filepath,word,fontsize,color);
            }
            Bitmap ret=null;
            try{
                int wi,hi;                wi=thumbWi;
                hi=thumbHi;                if(maintainAspect){
                    if(source.Width
                        >source.Height){
                        wi=thumbWi;
                        hi=(int)(source.Height*((decimal)thumbWi/source.Width));
                    }
                    else{
                        hi=thumbHi;
                        wi=(int)(source.Width*((decimal)thumbHi/source.Height));
                    }
                }
                ret=new Bitmap(wi,hi);
                using(Graphics g=Graphics.FromImage(ret)){
                    g.InterpolationMode=InterpolationMode.HighQualityBicubic;
                    g.FillRectangle(Brushes.White,0,0,wi,hi);
                    g.DrawImage(source,0,0,wi,hi);
                }
                source.Dispose();
            }
            catch{
                ret=null;
            }            return ret;
        }        /// <summary>
        /// 生成高压比的缩微图
        /// </summary>
        /// <param name="filepath">原图路径</param>
        /// <param name="newpath">新图路径</param>
        /// <param name="thumbWi">缩微图宽</param>
        /// <param name="thumbHi">缩微图高</param>
        /// <param name="maintainAspect">是否重置长宽比</param>
        /// <param name="Water">是否带水印信息,true 带水印,false 不带水印</param>
        public static void CreateThumbnailPerfect
            (string filepath,string newpath,int thumbWi,int thumbHi,bool maintainAspect,bool Water){
            Image myThumbnail=CreateThumbnail(filepath,thumbWi,thumbHi,false,Water);            var encoderParams=new EncoderParameters();
            var quality=new long[1];
            quality[0]=75;
            var encoderParam=new EncoderParameter(Encoder.Quality,quality);
            encoderParams.Param[0]=encoderParam;            ImageCodecInfo[] arrayICI=ImageCodecInfo.GetImageEncoders();
            ImageCodecInfo jpegICI=null;
            for(int x=0;x<arrayICI.Length;x++){
                if(arrayICI[x].FormatDescription.Equals("JPEG")){
                    jpegICI=arrayICI[x];
                    break;
                }
            }
            myThumbnail.Save(newpath,jpegICI,encoderParams);
            myThumbnail.Dispose();
        }        /// <summary>
        /// 
        /// </summary>
        /// <param name="filepath"></param>
        /// <param name="newpath"></param>
        /// <param name="thumbWi"></param>
        /// <param name="thumbHi"></param>
        /// <param name="maintainAspect"></param>
        /// <param name="Water"></param>
        public static void CreateThumbnailPerfect
            (
            string filepath,string word,int fontsize,Color color,string newpath,int thumbWi,int thumbHi,
            bool maintainAspect,bool Water){
            Image myThumbnail=CreateThumbnail(filepath,word,fontsize,color,thumbWi,thumbHi,false,Water);            var encoderParams=new EncoderParameters();
            var quality=new long[1];
            quality[0]=75;
            var encoderParam=new EncoderParameter(Encoder.Quality,quality);
            encoderParams.Param[0]=encoderParam;            ImageCodecInfo[] arrayICI=ImageCodecInfo.GetImageEncoders();
            ImageCodecInfo jpegICI=null;
            for(int x=0;x<arrayICI.Length;x++){
                if(arrayICI[x].FormatDescription.Equals("JPEG")){
                    jpegICI=arrayICI[x];
                    break;
                }
            }
            myThumbnail.Save(newpath,jpegICI,encoderParams);
            myThumbnail.Dispose();
        }

Answer 16

jsp不就是java嘛？java是可以处理图片的。