使用imgareaselect 辅助后台进行图片裁剪

Posted llguanli

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由于项目其中用到图片裁剪,本来能够不用到后台进行裁剪的,可是要兼容万恶的IE浏览器,所以不得不使用后台进行裁剪。

这次使用到imgareaselect?插件获取须要裁剪区域的坐标。再由后台进行裁剪操作。

先上个效果图再说

技术分享图片

可是这里有一个坑就是上传的图片过大,可能会造成裁剪的区域跟插件中显示的不一样,所以得如今后台对云图片进行压缩在裁剪

/**
	 * 等比例压缩算法: 
	 * 算法思想:依据压缩基数和压缩比来压缩原图,生产一张图片效果最接近原图的缩略图
	 * @param srcURL 原图地址
	 * @param deskURL 缩略图地址
	 * @param comBase 压缩基数
	 * @param scale 压缩限制(宽/高)比例  一般用1:
	 * 当scale>=1,缩略图height=comBase,width按原图宽高比例;若scale<1,缩略图width=comBase,height按原图宽高比例
	 * @throws Exception
	
	 */
	public static void saveMinPhoto(String srcURL, String deskURL, double comBase,
			double scale) throws Exception {
		File srcFile = new java.io.File(srcURL);
		String ext = srcURL.substring(srcURL.lastIndexOf(".") + 1); 
		Image src = ImageIO.read(srcFile);
		int srcHeight = src.getHeight(null);
		int srcWidth = src.getWidth(null);
		int deskHeight = 0;// 缩略图高
		int deskWidth = 0;// 缩略图宽
		double srcScale = (double) srcHeight / srcWidth;
		/**缩略图宽高算法*/
		if ((double) srcHeight > comBase || (double) srcWidth > comBase) {
			if (srcScale >= scale || 1 / srcScale > scale) {
				if (srcScale >= scale) {
					deskHeight = (int) comBase;
					deskWidth = srcWidth * deskHeight / srcHeight;
				} else {
					deskWidth = (int) comBase;
					deskHeight = srcHeight * deskWidth / srcWidth;
				}
			} else {
				if ((double) srcHeight > comBase) {
					deskHeight = (int) comBase;
					deskWidth = srcWidth * deskHeight / srcHeight;
				} else {
					deskWidth = (int) comBase;
					deskHeight = srcHeight * deskWidth / srcWidth;
				}
			}
		} else {
			deskHeight = srcHeight;
			deskWidth = srcWidth;
		}
		BufferedImage tag = new BufferedImage(deskWidth, deskHeight, BufferedImage.TYPE_3BYTE_BGR);
		tag.getGraphics().drawImage(src, 0, 0, deskWidth, deskHeight, null); //绘制缩小后的图
		FileOutputStream deskImage = new FileOutputStream(deskURL); //输出到文件流
		ImageIO.write(tag, ext, new File(deskURL)); 
		deskImage.close();
	}

这就是压缩之后在进行裁剪了。好了上完整代码先

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>上传头像</title>
<link rel="stylesheet" href="../../statics/css/ewt/style_1.css" type="text/css">
<link rel="stylesheet" href="../../statics/css/ewt/style_shangchuangtouxiang.css">
<link rel="stylesheet" type="text/css" href="../../statics/css/ewt/imgareaselect-default.css">
<link rel="stylesheet" href="../../statics/css/ewt/style.css" type="text/css" />
<link rel="stylesheet" href="../../statics/scripts/layer/skin/default/layer.css">
<script src="//cdn.bootcss.com/jquery/1.11.3/jquery.min.js"></script>
<script src="../../statics/scripts/include.js"></script>
<script src="../../statics/scripts/template.js"></script>
<script src="../../statics/scripts/layer/layer.js"></script>
<script src="../../statics/scripts/cropbox.js"></script>
<script src="../../statics/scripts/jquery.imgareaselect.pack.js"></script>
<script src="../../statics/scripts/ajaxfileupload.js"></script>
<script src="../../ewt/user/scripts/shangchuangtouxiang.js"></script>
<script src="../../ewt/common/config.js"></script>

</head>

<body>
<include src="../common/user_head.html"></include>
<div class="bggg">
<div class="box">
 <div class="bos">
   <include src="../common/user_menu.html"></include>
  <div class="bos_r">
  <div class="biaoti">
        <h3>上传头像</h3>
      </div>
  <div style=" width:915px; height: 400; display: block; overflow: hidden; margin: 30px auto; ">
       <div style=" width:430px;  margin:0 auto;">
       <div class="frame" style="margin: 0 0.3em; width: 300px; height: 300px; float: left;">
      <img id="photo" src="" style="width: 300px; height: 300px;"/>
    </div>

    <div id="preview" style="width: 100px; height: 100px; overflow: hidden; float: left;">
        <img src="" style="width: 100px; height: 100px;" id="smallImage"/>
    </div> 
    </div> 
    </div>
    <div  style=" width:425px;  margin:30px auto;">
    <div class="input_XZ1">
    <div class="input_XZ">选择图片</div>
    <input id="uplodimage"  class="input_style"   name="uplodimage" type="file" onchange="uplodImage(this)">
    </div>
     <input id="imgUrl" type="hidden">
    <input type="button" value="上传" class="input_SC" onclick="upold();">
    </div>
	<input type="hidden" id="x1" value="" />
	<input type="hidden" id="y1" value="" />
	<input type="hidden" id="x2" value="" />
	<input type="hidden" id="y2" value="" />
	<input type="hidden" id="w" value="" />
	<input type="hidden" id="h" value="" />

</div>
</div>
</div>


</div> 

<include src="../common/user_footer.html"></include>
</body>
</html>

js 代码

function preview(img, selection) {
    if (!selection.width || !selection.height)
        return;
    
    var scaleX = 100 / selection.width;
    var scaleY = 100 / selection.height;

    $(‘#preview img‘).css({
        width: Math.round(scaleX * 300),
        height: Math.round(scaleY * 300),
        marginLeft: -Math.round(scaleX * selection.x1),
        marginTop: -Math.round(scaleY * selection.y1)
    });

    $(‘#x1‘).val(selection.x1);
    $(‘#y1‘).val(selection.y1);
    $(‘#x2‘).val(selection.x2);
    $(‘#y2‘).val(selection.y2);
    $(‘#w‘).val(selection.width);
    $(‘#h‘).val(selection.height);    
}

$(function () {
   
});

//上传原始图片
function uplodImage(target) {
	if(checkImage(target)){
		var url = httpUtils.rootPath+‘/component/upload.do‘;
		$.ajaxFileUpload({
		    url: url, //用于文件上传的服务器端请求地址
		    secureuri: false, //是否须要安全协议,一般设置为false
		    fileElementId: ‘uplodimage‘, //文件上传域的ID
		    dataType: ‘json‘, //返回值类型 一般设置为json
		    success: function (data)  //服务器成功响应处理函数
		    {
		        var filePath =  data.filePath;
		        $(‘#photo‘).attr(‘src‘,httpUtils.rootPath+‘/component/upload.do?action=download&filepath=‘+filePath);
		        $(‘#smallImage‘).attr(‘src‘,httpUtils.rootPath+‘/component/upload.do?

action=download&filepath=‘+filePath); $(‘#imgUrl‘).val(filePath); $(‘#photo‘).imgAreaSelect({ aspectRatio: ‘1:1‘, x1: 50, y1: 50, x2: 241, y2: 241, handles: true, fadeSpeed: 200, onSelectChange: preview }); $(‘#x1‘).val("50"); $(‘#y1‘).val("50"); $(‘#x2‘).val("241"); $(‘#y2‘).val("241"); $(‘#w‘).val("191"); $(‘#h‘).val("191"); } }); } } //上传裁剪后的图片 function upold() { if($(‘#imgUrl‘).val()==‘‘){ layer.alert("请先选择图片在上传"); return false; } $.ajax({ type: "post", url:httpUtils.rootPath+‘/user/setHeadPicture‘, beforeSend: function(request) { request.setRequestHeader("jmtcp", header); }, async:false, data: { x:$(‘#x1‘).val(), y:$(‘#y1‘).val(), width: $(‘#w‘).val(), imgUrl : $(‘#imgUrl‘).val(), heigth: $(‘#h‘).val() }, dataType: "json", success: function(data){ if(data.code==1){ layer.alert(data.message,function(){ window.location.href = ‘../user/grzy.html‘; }); }else{ layer.alert(data.message); } } }); } function checkImage(target) { var isIE = /msie/i.test(navigator.userAgent) && !window.opera; var fileSize = 0; var filepath = target.value; // 为了避免转义反斜杠出问题。这里将对其进行转换 var re = /(\+)/g; var filename = filepath.replace(re, "#"); // 对路径字符串进行剪切截取 var one = filename.split("#"); // 获取数组中最后一个,即文件名称 var two = one[one.length - 1]; // 再对文件名称进行截取,以取得后缀名 var three = two.split("."); // 获取截取的最后一个字符串,即为后缀名 var last = three[three.length - 1]; // 加入须要推断的后缀名类型 var tp = "jpg,gif,bmp,JPG,GIF,BMP,png"; // 返回符合条件的后缀名在字符串中的位置 var rs = tp.indexOf(last); // 假设返回的结果大于或等于0。说明包括同意上传的文件类型 if(rs < 0){ layer.alert(‘您选择的上传文件不是有效的图片文件‘); return false; } // if (isIE && !target.files) { // IE浏览器 // var filePath = target.value; // 获得上传文件的绝对路径 // var fileSystem = new ActiveXObject("Scripting.FileSystemObject"); // // GetFile(path) 方法从磁盘获取一个文件并返回。 // var file = fileSystem.GetFile(filePath); // fileSize = file.Size; // 文件大小。单位:b // } // else { // 非IE浏览器 // fileSize = target.files[0].size; // } var img1 = document.getElementById(‘photo‘); //img1.dynsrc=target.value; //img1.fileSize:IE , fileObj.files[0].fileSize:chrome, fileObj.files[0].size:FF var fileSize = img1.fileSize || target.files[0].fileSize || target.files[0].size; var size = fileSize / 1024 / 1024; if (size > 5) { layer.alert("图片不能大于5M"); return false; } return true; }



后台代码

public class CutImageUtils {
	public static SecureRandom rnd = new SecureRandom();
	
	public static String cutImage(int x, int y, int width, int height,String srcPath) throws Exception{
		String root = ApplicationContext.getProperty("upload_folder");
		String imagePath = root+srcPath;
		 FileInputStream is = null;  
	     ImageInputStream iis = null; 
	     String uploadFolder = null ;
		String filepath = null  ;
		String serverName = null  ;
		uploadFolder = ApplicationContext.getProperties().getProperty("upload_folder").toString() ;
		filepath = generateServerFolder() ;
		serverName = generateServerName(srcPath) ;
        File file = new File(uploadFolder + filepath);  
        if (!file.exists()) {  
			file.mkdirs();
		} 
	  
         try {
        	// 读取图片文件  
        	saveMinPhoto(imagePath, imagePath, 300, 0.9d);
        	 //resetsize(imagePath, imagePath);
			is = new FileInputStream(imagePath);
			String ext = srcPath.substring(srcPath.lastIndexOf(".") + 1);  
			 Iterator<ImageReader> it = ImageIO.getImageReadersByFormatName(ext); 
			 ImageReader reader = it.next(); 
			// 获取图片流  
	         iis = ImageIO.createImageInputStream(is); 
	         reader.setInput(iis, true);  
	         ImageReadParam param = reader.getDefaultReadParam();  
	         /** 
	             *  
	             * 图片裁剪区域。Rectangle 指定了坐标空间中的一个区域。通过 Rectangle 对象 
	             *  
	             * 的左上顶点的坐标(x,y)、宽度和高度能够定义这个区域。

*/ Rectangle rect = new Rectangle(x, y, width, height); // 提供一个 BufferedImage。将其用作解码像素数据的目标。 param.setSourceRegion(rect); BufferedImage bi = reader.read(0, param); // 保存新图片 ImageIO.write(bi, ext, new File(uploadFolder + filepath + serverName)); } catch (FileNotFoundException e) { // TODO Auto-generated catch block if (is != null) is.close(); if (iis != null) iis.close(); e.printStackTrace(); } return filepath + serverName ; } /** * * @param config * @param file * @param request * @return */ public static String generateServerName(String clientPath) { //按当前时间的分钟毫秒+3位随机数 Calendar c = Calendar.getInstance(); String min = get(c,Calendar.MINUTE); String sec = get(c,Calendar.SECOND); String mis = get(c,Calendar.MILLISECOND); String rnd = random(); String ext = getFileExt(getClientName(clientPath)); return min + sec + mis + rnd + ext ; } /** 客户端文件名称 */ public static String getClientName(String clientPath) { if(null != clientPath){ int index1 = clientPath.lastIndexOf("/"); int index2 = clientPath.lastIndexOf("\\"); if(index2 > index1){ index1 = index2; } return clientPath.substring(index1+1,clientPath.length()); } return null; } public static String getFileExt(String fileName){ if(null != fileName){ int dot = fileName.lastIndexOf("."); if(dot >= 0){ return fileName.substring(dot); } } return ""; } public static String random(){ String value = String.valueOf(rnd.nextInt(1000)); if(value.length() < 3){ for(int i=value.length();i<3;i++){ value = "0" + value; } } return value; } public static String generateServerFolder() { //按当前年月日和小时生成文件路径 Calendar c = Calendar.getInstance(); String year = get(c,Calendar.YEAR); String mon = get(c,Calendar.MONTH); String day = get(c,Calendar.DAY_OF_MONTH); String hour = get(c,Calendar.HOUR_OF_DAY); return year + "/" + mon + "/" + day + "/" + hour + "/"; } public static String get(Calendar c,int field){ int v = c.get(field); if(field == Calendar.MONTH){ v += 1; } String value = String.valueOf(v); if(value.length() == 1){ value = "0" + value; } return value; } /** * 缩小图片到固定长高 * @param srcImagePath 读取图片路径 * @param toImagePath 写入图片路径 * @param width 缩小后图片宽度 * @param height 缩小后图片长度 * @throws IOException */ public static void reduceImageByWidthHeight(String srcImagePath, String toImagePath, int width, int height) throws IOException{ FileOutputStream out = null; try{ //读入文件 File file = new File(srcImagePath); String ext = srcImagePath.substring(srcImagePath.lastIndexOf(".") + 1); // 构造Image对象 BufferedImage src = javax.imageio.ImageIO.read(file); // 缩小边长 BufferedImage tag = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB); // 绘制缩小后的图片 tag.getGraphics().drawImage(src, 0, 0, width, height, null); out = new FileOutputStream(toImagePath); ImageIO.write(tag, ext, new File(toImagePath)); }catch(Exception e){ e.printStackTrace(); }finally{ if(out != null){ out.close(); } out = null; System.gc(); } } /** * 等比例压缩算法: * 算法思想:依据压缩基数和压缩比来压缩原图。生产一张图片效果最接近原图的缩略图 * @param srcURL 原图地址 * @param deskURL 缩略图地址 * @param comBase 压缩基数 * @param scale 压缩限制(宽/高)比例 一般用1: * 当scale>=1,缩略图height=comBase,width按原图宽高比例;若scale<1,缩略图width=comBase,height按原图宽高比例 * @throws Exception */ public static void saveMinPhoto(String srcURL, String deskURL, double comBase, double scale) throws Exception { File srcFile = new java.io.File(srcURL); String ext = srcURL.substring(srcURL.lastIndexOf(".") + 1); Image src = ImageIO.read(srcFile); int srcHeight = src.getHeight(null); int srcWidth = src.getWidth(null); int deskHeight = 0;// 缩略图高 int deskWidth = 0;// 缩略图宽 double srcScale = (double) srcHeight / srcWidth; /**缩略图宽高算法*/ if ((double) srcHeight > comBase || (double) srcWidth > comBase) { if (srcScale >= scale || 1 / srcScale > scale) { if (srcScale >= scale) { deskHeight = (int) comBase; deskWidth = srcWidth * deskHeight / srcHeight; } else { deskWidth = (int) comBase; deskHeight = srcHeight * deskWidth / srcWidth; } } else { if ((double) srcHeight > comBase) { deskHeight = (int) comBase; deskWidth = srcWidth * deskHeight / srcHeight; } else { deskWidth = (int) comBase; deskHeight = srcHeight * deskWidth / srcWidth; } } } else { deskHeight = srcHeight; deskWidth = srcWidth; } BufferedImage tag = new BufferedImage(deskWidth, deskHeight, BufferedImage.TYPE_3BYTE_BGR); tag.getGraphics().drawImage(src, 0, 0, deskWidth, deskHeight, null); //绘制缩小后的图 FileOutputStream deskImage = new FileOutputStream(deskURL); //输出到文件流 ImageIO.write(tag, ext, new File(deskURL)); deskImage.close(); } public static void main(String[] args) { try { String src = CutImageUtils.cutImage(11, 12, 100, 100, "2017/01/04/17/6348162d-5b50-4e7d-b414-93140498f8de.jpg"); System.out.println(src); } catch (Exception e) { // TODO Auto-generated catch block e.printStackTrace(); } } }






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