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tuseronituseroni
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Merge branch 'master' of github.com:tuseroni/stegano.js
2 parents 625f9d4 + 12bd386 commit 1d7abb3

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‎README

+9-9
Original file line numberDiff line numberDiff line change
@@ -1,22 +1,22 @@
11
a javascript and HTML based steganography encoder/decoder.
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encoder.html takes a .png file as the cover and any file data file as the hidden data. the hidden data cannot be bigger than the width*the height of the cover image (in bytes)
3-
decoder.html takes a png with the name canvas.png (the ability to pick arbitrary files coming soon) and extracts the data from the image.
3+
decoder.html takes an encoded png selected by the user and extracts the data from the image.
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the encoder uses a Pseudo-Random number generator seeded with a hash of a string which serves as the password. the same password must be used for decoding as was used for encoding.
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requires Firefox (dont know the minimum version, but just best to have the latest)
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still to do:
10-
. arbitrary data hidden inside audio files
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. arbitrary data hidden inside video files
12-
. clean up the page a bit (planning to move most of it to a webworker and use that to update a progress bar element, should also give a boost to performance and usability)
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. move a bunch of the code into a greasemonkey script (or BACK into a greasemonkey script)
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. make it work in chrome and maybe ie9 or 10
15-
. celebrate
10+
* arbitrary data hidden inside audio files
11+
* arbitrary data hidden inside video files
12+
* clean up the page a bit (planning to move most of it to a webworker and use that to update a progress bar element, should also give a boost to performance and usability)
13+
* move a bunch of the code into a greasemonkey script (or BACK into a greasemonkey script)
14+
* make it work in chrome and maybe ie9 or 10
15+
* celebrate
1616

1717
wish i could do:
18-
. use some other image format than png for the cover image, but all images are converted to png by the canvas tag
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. suggest a name for the download (i wish base64 uris had a filename hint optional part, something to tell the browser "try this filename when saving this file" so like (data:|foo.png;base64,data)
18+
* use some other image format than png for the cover image, but all images are converted to png by the canvas tag
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* suggest a name for the download (i wish base64 uris had a filename hint optional part, something to tell the browser "try this filename when saving this file" so like (data:|foo.png;base64,data)
2020

2121
credits:
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Chris McKenzie, his project:

‎decoder.html

+31-7
Original file line numberDiff line numberDiff line change
@@ -1,8 +1,30 @@
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<html>
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<body>
3-
<img src="canvas2.png">
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<input type="file" id="img" accept="image/png">
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<button onclick="makeImg()">Decode It</button>
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<script type="text/javascript">
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var contextNode=null;
7+
var redIndicies=[];
8+
function makeImg()
9+
{
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var outerImg=document.getElementById("img");
11+
if(!outerImg.files[0])
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{
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return;
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}
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var imgdat=outerImg.files[0];
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var reader = new FileReader();
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reader.onload=function(event)
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{
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var img=new Image;
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img.onload=function()
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{
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doThings(this);
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}
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img.src=event.target.result;
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}
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reader.readAsDataURL(imgdat);
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}
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function base64_encode (data,isutf8) {
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// Encodes string using MIME base64 algorithm
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//
@@ -53,11 +75,13 @@
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var randnum=Math.floor(rng()*newData.length);
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var redIndex=randnum-(randnum%4);
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var name="";
78+
5679
if(newData[redIndex]==-1)
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{
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return getName(rng,imageData,newData,deletedbytes);
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}
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len=((imageData[redIndex] & 7)<<5 | (imageData[redIndex+1] & 3)<<3 |(imageData[redIndex+2] & 7));
84+
//redIndicies.push(redIndex);
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newData[redIndex]=-1;
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deletedbytes++;
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for(var i=0;i<len;i++)
@@ -70,6 +94,7 @@
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i--;
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continue;
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}
97+
//redIndicies.push(redIndex);
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byte=((imageData[redIndex] & 7)<<5 | (imageData[redIndex+1] & 3)<<3 |(imageData[redIndex+2] & 7));
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name+=String.fromCharCode(byte);
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newData[redIndex]=-1;
@@ -89,6 +114,7 @@
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i--;
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continue;
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}
117+
//redIndicies.push(redIndex);
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byte=((imageData[redIndex] & 7)<<5 | (imageData[redIndex+1] & 3)<<3 |(imageData[redIndex+2] & 7));
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len|=byte<<(i*8);
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newData[redIndex]=-1;
@@ -189,12 +215,8 @@
189215
} (Array.prototype.slice.call(arguments)));
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};
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192-
function doThings()
193-
{
194-
if(!contextNode)
218+
function doThings(img)
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{
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return;
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}
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var canvas = null,
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ctx = null,
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canvas = document.createElement("canvas");
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var b = document.getElementsByTagName("body")[0];
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b.appendChild(canvas);
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ctx = canvas.getContext("2d");
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var img = contextNode;
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// apply the width and height to the canvas element
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canvas.width = img.width;
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canvas.height = img.height;
@@ -238,6 +259,7 @@
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retObj=getBodyLength(rng,imageData,newData,deletedbytes);
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newData=retObj.newData;
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len=retObj["len"];
262+
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for(var i = 0; i < len; i++){
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var randnum=Math.floor(rng()*newData.length);
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var redIndex=randnum-(randnum%4);
@@ -247,11 +269,13 @@
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i--;
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continue;
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}
272+
//redIndicies.push(redIndex);
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byte=((imageData[redIndex] & 7)<<5 | (imageData[redIndex+1] & 3)<<3 |(imageData[redIndex+2] & 7));
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body+=String.fromCharCode(byte);
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newData[redIndex]=-1;
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deletedbytes++;
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}
278+
//alert(redIndicies);
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var base64string=base64_encode(body,true);
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url="data:application/octet-stream;base64,"+base64string;
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var theif=document.createElement("iframe");

‎encoder.html

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@@ -180,11 +180,17 @@
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var width = canvas.width;
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var pass=prompt("please enter a password");
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var rng = new Alea(pass);
183+
var redIndicies=[];
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for(var i = 0; i<length; i++)
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{
185186
newData[i]=i;
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}
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var bytes=String.fromCharCode(nameLen)+fileName+getLengthInChars(fileLen)+file;
189+
if(imageData.length/4<bytes.length)
190+
{
191+
alert("innerFile too big")
192+
return;
193+
}
188194
for(var i = 0; i <= bytes.length; i++){
189195
var randnum=Math.floor(rng()*newData.length);
190196
var redIndex=randnum-(randnum%4);
@@ -193,19 +199,21 @@
193199
i--;
194200
continue;
195201
}
202+
//redIndicies.push(redIndex);
196203
imageData[redIndex]=((imageData[redIndex] & (~7)) | ((bytes.charCodeAt(i)>>5)&7))
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imageData[redIndex+1]=((imageData[redIndex+1] & (~3)) | ((bytes.charCodeAt(i)>>3)&3))
198205
imageData[redIndex+2]=((imageData[redIndex+2] & (~7)) | ((bytes.charCodeAt(i))&7))
199206
newData[redIndex]=-1;
200207
}
208+
//alert(redIndicies);
201209
image.data=imageData;
202210
ctx.putImageData(image,0,0);
203211
canvas.style.display="";
204212
}
205213
</script>
206-
<body onload="doThings()">
207-
<p>select Outer Image:</p>
208-
<p><input type="file" id="img"></p>
214+
<body>
215+
<p>select Outer Image(PNG format):</p>
216+
<p><input type="file" id="img" accept="image/*"></p>
209217
<p>select innerFile:</p>
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<p><input type="file" id="file"></p>
211219
<button onclick="makeImg()">Do it!</button>

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