remove png functions, better versions in Ox.Image

source/Ox/js/Encoding.js

@@ -322,101 +322,6 @@
         );
     };
 
-    /*@
-    Ox.encodePNG <f> Encodes a string into an image, returns a new image
-        The string is compressed with deflate (by proxy of canvas), prefixed
-        with its length (four bytes), and encoded bitwise into the red, green
-        and blue bytes of all fully opaque pixels of the image, by flipping, if
-        necessary, the least significant bit, so that for every byte, the total
-        number of bits set to to 1, modulo 2, is the bit that we are encoding.
-    (img, src) -> <e> An image into which the string has been encoded
-        img <e> Any JavaScript PNG image object
-        str <s> The string to be encoded
-    @*/
-    // fixme: remove, exists in image module
-    Ox.encodePNG = function(img, str) {
-        var c = Ox.canvas(img), i = 0;
-        // Compress the string
-        str = Ox.encodeDeflate(str);
-        // Prefix the string with its length, as a four-byte value
-        str = Ox.pad(Ox.encodeBase256(str.length), 4, Ox.char(0)) + str;
-        // Create an array of bit values
-        Ox.forEach(Ox.flatten(Ox.map(str, function(chr) {
-            return Ox.map(Ox.range(8), function(i) {
-                return chr.charCodeAt(0) >> 7 - i & 1;
-            });
-        })), function(bit) {
-            // Skip all pixels that are not fully opaque
-            while (i < c.data.length && i % 4 == 0 && c.data[i + 3] < 255) {
-                i += 4;
-            }
-            if (i == c.data.length) {
-                throw new RangeError('PNG codec can\'t encode data');
-            }
-            // If the number of bits set to one, modulo 2 is equal to the bit,
-            // do nothing, otherwise, flip the least significant bit.
-            c.data[i] += c.data[i].toString(2).replace(/0/g, '').length % 2
-                == bit ? 0 : c.data[i] % 2 ? -1 : 1;
-            i++;
-        });
-        c.context.putImageData(c.imageData, 0, 0);
-        img = new Image();
-        img.src = c.canvas.toDataURL();
-        return img;
-        /*
-        wishlist:
-        - only use deflate if it actually shortens the message
-        - encode a decoy message into the least significant bit
-          (and flip the second least significant bit, if at all)
-        - write an extra png chunk containing some key
-        */
-    };
-
-    /*@
-    Ox.decodePNG <f> Decodes an image, returns a string
-        For every red, green and blue byte of every fully opaque pixel of the
-        image, one bit, namely the number of bits of the byte set to one, modulo
-        2, is being read, the result being the string, prefixed with its length
-        (four bytes), which is decompressed with deflate (by proxy of canvas).
-        (img, callback) -> <u> undefined
-            img <e> The image into which the string has been encoded
-            callback <f> Callback function
-                str <s> The decoded string
-    @*/
-    
-    Ox.decodePNG = function(img, callback) {
-        var bits = '', data = Ox.canvas(img).data, flag = false, i = 0,
-            len = 4, str = '';
-        while (len) {
-            // Skip all pixels that are not fully opaque
-            while (i < data.length && i % 4 == 0 && data[i + 3] < 255) {
-                i += 4;
-            }
-            if (i == data.length) {
-                break;
-            }
-            // Read the number of bits set to one, modulo 2
-            bits += data[i].toString(2).replace(/0/g, '').length % 2;
-            if (++i % 8 == 0) {
-                // Every 8 bits, add one byte
-                str += Ox.char(parseInt(bits, 2));
-                bits = '';
-                // When length reaches 0 for the first time,
-                // decode the string and treat it as the new length
-                if (--len == 0 && !flag) {
-                    flag = true;
-                    len = Ox.decodeBase256(str);
-                    str = '';
-                }
-            }
-        }
-        try {
-            Ox.decodeDeflate(str, callback);
-        } catch (e) {
-            throw new RangeError('PNG codec can\'t decode image');
-        }
-    };
-
     /*@
     Ox.encodeUTF8 <f> Encodes a string as UTF-8
         see http://en.wikipedia.org/wiki/UTF-8
@@ -496,4 +401,4 @@
         return ret;
     };
 
-})();
+})();