html5 - prevent client from seeing image used in a javascript canvas -


i have path image in server. paths used javascript load image use in canvas, in following way: js script draws image in canvas: hides parts of image(by covering them black layers)

the problem user can read js script image url, , load entirely(without hidden parts)

is there way solve issue can think off?

    imagemap.src = 'pathtojpgimage.jpg';     imagemap.onload = function() {       // function draws black circles hiding areas of map       coverhidenareas();     }

i've got javascript image scrambler can use. scramble function works on image element. careful getting onload loop. can see scramble onload , reset onload avoid looping when setting new value.

function scramble(el){      var v=document.createelement('canvas')      var w=v.width=el.width,h=v.height=el.height,c=v.getcontext('2d')      c.drawimage(el,0,0)      var id=c.getimagedata(0,0,w,h),d=id.data,l=d.length,i=l/4,a=[]      for(;--i;)a[i]=i      function s(a){          var l=a.length,x=l>>3,y,t,i=0,s=[]          if(l<8)return          for(;i<l;i+=x)s[i/x]=s(a.slice(i,i+x))          for(i=4;--i;)y=[6,4,7,5,1,3,0,2][i],t=s[i],s[i]=s[y],s[y]=t          s=[].concat.apply([],s)          return s      }      var n=c.createimagedata(w,h),d=n.data,a=s(a)      for(var i=0;i<l;i++)d[i]=d[(a[i>>2]*4)+(i%4)]      c.putimagedata(n,0,0)      el.src=c.canvas.todataurl()  }    function btnscrambleclick() {      var srcimage = document.getelementbyid('srcimage');    srcimage.onload = null;    scramble(srcimage);      }    function previewfile() {    var srcimage = document.getelementbyid('srcimage');    var file = document.queryselector('input[type=file]').files[0];    var reader = new filereader();      reader.onloadend = function() {      srcimage.src = reader.result;    }      if (file) {      reader.readasdataurl(file);    } else {      srcimage.src = "";    }  };    previewfile();
<input type="file" onchange="previewfile()"/>    <p>  <button id="btnscramble" onclick="btnscrambleclick()">scramble / unscramble</button>  </p>    <div id="main">    <img id="srcimage" src="" alt="uploaded image" onload="btnscrambleclick()">  </div>


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