security-and-privacy/CanvasBlocker
security-and-privacy/CanvasBlocker
1
0
Fork 0
mirror of https://github.com/kkapsner/CanvasBlocker synced 2025-01-18 09:28:52 +01:00
Code Releases Activity

Changed rng interface to use colors instead of separate channels.

Browse Source
This commit is contained in:
kkapsner 2017-08-07 08:49:49 +02:00
parent 26457b2a7f
commit 921c7dbd5f
2 changed files with 60 additions and 6 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

34
lib/modifiedAPI.js
View File

@ -59,10 +59,22 @@
var {imageData, source} = getImageData(window, context); var {imageData, source} = getImageData(window, context);
var desc = imageData.data; var desc = imageData.data;
var l = desc.length; var l = desc.length;
var rng = randomSupply.getRng(l, window);
for (var i = 0; i < l; i += 1){ var ignoredColors = {};
desc[i] = rng(source[i], i); var rng = randomSupply.getPixelRng(l, window, ignoredColors);
for (var i = 0; i < l; i += 4){
var [r, g, b, a] = rng(
source[i + 0],
source[i + 1],
source[i + 2],
source[i + 3],
i / 4
);
desc[i + 0] = r;
desc[i + 1] = g;
desc[i + 2] = b;
desc[i + 3] = a;
} }
var canvas = original.cloneNode(true); var canvas = original.cloneNode(true);
context = window.HTMLCanvasElement.prototype.getContext.call(canvas, "2d"); context = window.HTMLCanvasElement.prototype.getContext.call(canvas, "2d");
@ -337,10 +349,20 @@
var xPixels = pixels; var xPixels = pixels;
var ret = original.apply(this, window.Array.from(arguments)); var ret = original.apply(this, window.Array.from(arguments));
var l = xPixels.length; var l = xPixels.length;
var rng = randomSupply.getRng(l, window); var rng = randomSupply.getPixelRng(l, window, {});
for (var i = 0; i < l; i += 1){ for (var i = 0; i < l; i += 4){
xPixels[i] = rng(xPixels[i], i); var [r, g, b, a] = rng(
xPixels[i + 0],
xPixels[i + 1],
xPixels[i + 2],
xPixels[i + 3],
i / 4
);
xPixels[i + 0] = r;
xPixels[i + 1] = g;
xPixels[i + 2] = b;
xPixels[i + 3] = a;
} }
return ret; return ret;

32
lib/randomSupplies.js
View File

@ -68,6 +68,22 @@
// XOR the bit and the value to alter the last bit of it... or not // XOR the bit and the value to alter the last bit of it... or not
return value ^ bit; return value ^ bit;
}; };
},
getPixelRng: function(length, window, ignoredColors){
var rng = this.getRng(length, window);
return function(r, g, b, a, i){
var index = String.fromCharCode(r, g, b, a);
if (ignoredColors[index]){
return [r, g, b, a];
}
var baseIndex = i * 4;
return [
rng(r, baseIndex + 0),
rng(g, baseIndex + 1),
rng(b, baseIndex + 2),
rng(a, baseIndex + 3)
];
}
} }
}; };
@ -92,6 +108,22 @@
// XOR the last bit to alter it... or not // XOR the last bit to alter it... or not
return value ^ (rnd & 0x01); return value ^ (rnd & 0x01);
}; };
},
getPixelRng: function(length, window, ignoredColors){
var rng = this.getRng(length, window);
return function(r, g, b, a, i){
var index = String.fromCharCode(r, g, b, a);
if (ignoredColors[index]){
return [r, g, b, a];
}
var baseIndex = i * 4;
return [
rng(r, baseIndex + 0),
rng(g, baseIndex + 1),
rng(b, baseIndex + 2),
rng(a, baseIndex + 3)
];
}
} }
}; };
}()); }());