init

build/js/ox.png.js

@@ -0,0 +1,57 @@
+onmessage = function(e) {
+    if (e.data.message) {
+        
+    } else {
+        
+    }
+}
+
+function encode() {
+    str = Ox.encodeUTF8(str);
+    var c = Ox.canvas(img), len = str.length;
+    if (len > maxLength(img.width, img.height)) {
+        throw new RangeError("PNG codec can't encode " + len +
+                " bytes into " + (img.width * img.height) + " pixels");
+    }
+    len = Ox.pad(Ox.encodeBase256(len), 4, Ox.char(0));
+    Ox.each(Ox.map(len + str, function(byte) {
+        return Ox.map(new Array(8), function(v, i) {
+            return byte.charCodeAt(0) >> 7 - i & 1;
+        }).join("");
+    }).join(""), function(i, bit) {
+        var index, byte = c.data[index = parseInt(i * 4/3)];
+        c.data[index] = bit == xor(byte) ? byte :
+                byte & 254 | !(byte & 1);
+    });
+    c.context.putImageData(c.imageData, 0, 0);
+    postMessage(c.canvas.toDataURL());
+}
+
+function decode() {
+    var c = Ox.canvas(img), bits = "", str = "", i = 0; len = 4, flag = false;
+    do {
+        bits += xor(c.data[parseInt(i * 4/3)]);
+        if (++i % 8 == 0) {
+            str += Ox.char(parseInt(bits, 2));
+            bits = "";
+            len--;
+            if (len == 0 && !flag) {
+                if ((len = Ox.decodeBase256(str)) >
+                        maxLength(img.width, img.height)) {
+                    throwPNGError();
+                }
+                str = "";
+                flag = true;
+            }
+        }
+    } while (len);
+    try {
+        return Ox.decodeUTF8(str);
+    } catch(e) {
+        throwPNGError();
+    }
+}
+
+function throwError() {
+    throw new RangeError("PNG codec can't decode image");
+}