Ox.load.Image = function(options, callback) { //@ Image ------------------------------------------------------------------ /*@ Ox.Image Generic image object To render the image as an image element, use its src() method, to render it as a canvas, use its canvas property. (src, callback) -> undefined (width, height, callback) -> undefined (width, height, background, callback) -> undefined src Image source (local, remote or data URL) width Width in px image Height in px background <[n]> Background color (RGB or RGBA) @*/ Ox.Image = function() { var self = {}, that = {}; self.callback = arguments[arguments.length - 1]; if (arguments.length == 2) { self.src = arguments[0]; self.image = new Image(); self.image.onload = init; self.image.src = self.src; } else { self.width = arguments[0]; self.height = arguments[1]; self.background = arguments.length == 4 ? arguments[2] : [0, 0, 0, 0]; init(); } function error(mode) { throw new RangeError('PNG codec can\'t ' + mode + ' ' + ( mode == 'encode' ? 'data' : 'image' )); } function getCapacity(bpb) { var capacity = 0; that.forEach(function(rgba) { capacity += rgba[3] == 255 ? bpb * 3/8 : 0; }); return capacity; } function getIndex() { if (arguments.length == 1) { xy = arguments[0]; } else { xy = [arguments[0], arguments[1]]; } return ( Ox.mod(xy[0], self.width) + Ox.mod(xy[1] * self.width, self.width * self.height) ) * 4; } function getXY(index) { index /= 4; return [index % self.width, Math.floor(index / self.width)]; } function init() { if (self.image) { self.width = self.image.width; self.height = self.image.height; } that.canvas = Ox.element('').attr({ width: self.width, height: self.height }); that.context = that.canvas[0].getContext('2d'); if (self.image) { that.context.drawImage(self.image, 0, 0); } else if (Ox.sum(self.background)) { that.context.fillStyle(self.background); that.context.fillRect(0, 0, self.width, self.height); } that.imageData = that.context.getImageData( 0, 0, self.width, self.height ); self.data = that.imageData.data; self.callback(that); } function setSL(sl, d) { var c = sl == 's' ? 1 : 2; return that.map(function(rgba) { var hsl = Ox.hsl([rgba[0], rgba[1], rgba[2]]), rgb; hsl[c] = d < 0 ? hsl[c] * (d + 1) : hsl[c] + (1 - hsl[c]) * d; rgb = Ox.rgb(hsl); return Ox.merge(rgb, rgba[3]); }); } /*@ blur Apply blur filter (val) -> The image object val Amount of blur (1 to 5, more is slow) @*/ that.blur = function(val) { var filter = [], size = val * 2 + 1; sum = 0 Ox.loop(size, function(x) { Ox.loop(size, function(y) { var isInCircle = +(Math.sqrt( Math.pow(x - val, 2) + Math.pow(y - val, 2) ) <= val); sum += isInCircle; filter.push(isInCircle) }); }); filter = filter.map(function(val) { return val / sum; }) return that.filter(filter); }; //@ canvas Canvas object /*@ channel Reduce the image to one channel (channel) -> The image object channel 'r', 'g', 'b', 'a', 'h', 's' or 'l' @*/ that.channel = function(str) { str = str[0].toLowerCase(); return that.map(function(rgba) { var i = ['r', 'g', 'b', 'a'].indexOf(str), rgb, val; if (i > -1) { return Ox.map(rgba, function(v, c) { return str == 'a' ? (c < 3 ? rgba[3] : 255) : (c == i || c == 3 ? v : 0); }); } else { i = ['h', 's', 'l'].indexOf(str); val = Ox.hsl([rgba[0], rgba[1], rgba[2]])[i]; rgb = i == 0 ? Ox.rgb([val, 1, 0.5]) : Ox.map(Ox.range(3), function(v) { return parseInt(val * 255); }); return Ox.merge(rgb, rgba[3]); } }); } //@ context 2D drawing context /*@ contour Apply contour filter () -> The image object @*/ that.contour = function(val) { return that.filter([ +1, +1, +1, +1, -7, +1, +1, +1, +1 ]); }; /*@ depth Reduce the bit depth (depth) -> The image object depth Bits per channel (1 to 7) @*/ that.depth = function(val) { var pow = Math.pow(2, 8 - val); return that.map(function(rgba) { return rgba.map(function(v, i) { return i < 3 ? Math.floor(v / pow) * pow/* * 255 / val*/ : v; }); }); }; /*@ edges Apply edges filter () -> The image object @*/ that.edges = function(val) { return that.filter([ -1, -1, -1, -1, +8, -1, -1, -1, -1 ]).saturation(-1); }; /*@ emboss Apply emboss filter () -> The image object @*/ that.emboss = function(val) { return that.filter([ -1, -1, +0, -1, +0, +1, +0, +1, +1 ], 128).saturation(-1); }; /*@ encode Encodes a string into the image For most purposes, deflate and mode should be omitted, since the defaults make the existence of the message harder to detect. A valid use case for deflate and mode would be to first encode a more easily detected decoy string, and only then the secret string: image.encode(decoy, false, 1, function(image) { image.encode(secret, -1, callback); }). (str, callback) -> The image object (unmodified) (str, deflate, callback) -> The image object (unmodified) (str, mode, callback) -> The image object (unmodified) (str, deflate, mode, callback) -> The image object (unmodified) (str, mode, deflate, callback) -> The image object (unmodified) str The string to be encoded callback Callback function image The image object (modified) deflate If true, encode the string with deflate mode Encoding mode If mode is between -7 and 0, the string will be encoded one bit per byte, as the number of bits within that byte set to 1, modulo 2, by flipping, if necessary, the most (mode -7) to least (mode 0) significant bit. If mode is between 1 and 255, the string will be encoded bitwise into all bits per byte that, in mode, are set to 1. @*/ that.encode = function(str) { var callback = arguments[arguments.length - 1], deflate = Ox.isBoolean(arguments[1]) ? arguments[1] : Ox.isBoolean(arguments[2]) ? arguments[2] : true, mode = Ox.isNumber(arguments[1]) ? arguments[1] : Ox.isNumber(arguments[2]) ? arguments[2] : 0, b = 0, bin, // Array of bits per byte to be modified (0 is LSB) bits = mode < 1 ? [-mode] : Ox.map(Ox.range(8), function(bit) { return mode & 1 << bit ? bit : null; }), cap = getCapacity(bits.length), len; Ox.print("CAPACITY", cap) // Compress the string str = Ox[deflate ? 'encodeDeflate' : 'encodeUTF8'](str); len = str.length; // Prefix the string with its length, as a four-byte value str = Ox.pad(Ox.encodeBase256(len), 4, '\u0000') + str; str.length > cap && error('encode'); while (str.length < cap) { str += str.substr(4, len); } str = str.substr(0, Math.ceil(cap)); // Create an array of bit values bin = Ox.flatten(Ox.map(str, function(chr) { return Ox.map(Ox.range(8), function(i) { return chr.charCodeAt(0) >> 7 - i & 1; }); })); b = 0; that.forEach(function(rgba, xy) { // If alpha is not 255, the RGB values may not be preserved if (rgba[3] == 255) { var index = getIndex(xy); Ox.loop(3, function(c) { // fixme: use: var data = that.context.imageData.data[i + c] var i = index + c; Ox.forEach(bits, function(bit) { if (( mode < 1 // If the number of bits set to 1, mod 2 ? Ox.sum(Ox.range(8).map(function(bit) { return +!!(self.data[i] & 1 << bit); })) % 2 // or the one bit in question : +!!(self.data[i] & 1 << bit) // is not equal to the data bit ) != bin[b++]) { // then flip the bit self.data[i] ^= 1 << bit; } }); }); } }); that.context.putImageData(that.imageData, 0, 0); callback(that); return that; }; /*@ decode Decode encoded string (callback) -> The image object (unmodified) (deflate, callback) -> The image object (unmodified) (mode, callback) -> The image object (unmodified) (deflate, mode, callback) -> The image object (unmodified) (mode, deflate, callback) -> The image object (unmodified) deflate If true, decode the string with deflate mode See encode method callback Callback function image The image object (modified) @*/ that.decode = function() { var callback = arguments[arguments.length - 1], deflate = Ox.isBoolean(arguments[0]) ? arguments[0] : Ox.isBoolean(arguments[1]) ? arguments[1] : true, mode = Ox.isNumber(arguments[0]) ? arguments[0] : Ox.isNumber(arguments[1]) ? arguments[1] : 0, bin = '', // Array of bits per byte to be modified (0 is LSB) bits = mode < 1 ? [-mode] : Ox.map(Ox.range(8), function(b) { return mode & 1 << b ? b : null; }), done = 0; len = 4, str = ''; that.forEach(function(rgba, xy) { if (rgba[3] == 255) { var index = getIndex(xy); Ox.loop(3, function(c) { var i = index + c; Ox.forEach(bits, function(bit) { bin += mode < 1 // Read the number of bits set to 1, mod 2 ? Ox.sum(Ox.range(8).map(function(bit) { return +!!(self.data[i] & 1 << bit); })) % 2 // or the one bit in question : +!!(self.data[i] & 1 << bit); if (bin.length == 8) { // Every 8 bits, add one byte to the string str += Ox.char(parseInt(bin, 2)); bin = ''; if (str.length == len) { if (++done == 1) { // After 4 bytes, parse string as length len = Ox.decodeBase256(str); if ( len <= 0 || len > getCapacity(bits.length) - 4 ) { error('decode'); } str = ''; } else { // After length more bytes, break return false; } } } }); return done != 2; }); return done != 2; } }); try { if (deflate) { Ox.decodeDeflate(str, callback); } else { callback(Ox.decodeUTF8(str)); } } catch (e) { error('decode'); } } /*@ filter Pixel-wise filter function Undocumented, see source code (filter) -> The image object (filter, bias) -> The image object filter <[n]> Filter matrix bias Bias @*/ that.filter = function(filter, bias) { bias = bias || 0; var filterSize = Math.sqrt(filter.length), d = (filterSize - 1) / 2, imageData = that.context.createImageData(self.width, self.height), data = []; that.imageData = that.context.getImageData(0, 0, self.width, self.height); self.data = that.imageData.data; Ox.loop(0, self.data.length, 4, function(i) { var filterIndex = 0, xy = getXY(i); Ox.loop(3, function(c) { data[i + c] = 0; }); Ox.loop(-d, d + 1, function(x) { Ox.loop(-d, d + 1, function(y) { var pixelIndex = getIndex(xy[0] + x, xy[1] + y); Ox.loop(3, function(c) { data[i + c] += self.data[pixelIndex + c] * filter[filterIndex]; }); filterIndex++; }); }); }); Ox.loop(0, self.data.length, 4, function(i) { Ox.loop(4, function(c) { imageData.data[i + c] = c < 3 ? Ox.limit(Math.round(data[i + c] + bias), 0, 255) : self.data[i + c]; }); }); that.context.putImageData(imageData, 0, 0); that.imageData = imageData; self.data = data; return that; }; /*@ forEach Pixel-wise forEach function (fn) -> The image object fn Iterator function rgba <[n]> RGBA values xy <[n]> XY coordinates @*/ that.forEach = function(fn) { Ox.loop(0, self.data.length, 4, function(i) { return fn([ self.data[i], self.data[i + 1], self.data[i + 2], self.data[i + 3] ], getXY(i)); }) return that; }; that.hue = function(val) { return that.map(function(rgba) { var hsl = Ox.hsl([rgba[0], rgba[1], rgba[2]]), rgb; hsl[0] = (hsl[0] + val) % 360; rgb = Ox.rgb(hsl); return Ox.merge(rgb, rgba[3]); }); }; //@ imageData Image data object /*@ invert Apply invert filter () -> The image object @*/ that.invert = function() { return that.map(function(rgba) { return [255 - rgba[0], 255 - rgba[1], 255 - rgba[2], rgba[3]]; }); }; /*@ lightness Apply lightness filter (val) -> The image object val Amount, from -1 (darkest) to 1 (lightest) @*/ that.lightness = function(val) { return setSL('l', val); }; /*@ map Pixel-wise map function (fn) -> The image object fn Iterator function rgba <[n]> RGBA values xy <[n]> XY coordinates @*/ that.map = function(fn) { that.imageData = that.context.getImageData(0, 0, self.width, self.height); self.data = that.imageData.data; Ox.loop(0, self.data.length, 4, function(i) { fn([ self.data[i], self.data[i + 1], self.data[i + 2], self.data[i + 3] ], getXY(i)).forEach(function(val, c) { self.data[i + c] = val; }); }) that.context.putImageData(that.imageData, 0, 0); return that; }; /*@ mosaic Apply mosaic filter (size) -> The image object size Mosaic size @*/ that.mosaic = function(size) { that.forEach(function(rgba, xy) { if (xy[0] % size == 0 && xy[1] % size == 0) { Ox.loop(size, function(x) { Ox.loop(size, function(y) { var hsl, rgb; if ((x == 0 || y == 0) && !(x == size - 1 || y == size - 1)) { that.pixel(xy[0] + x, xy[1] + y, rgba.map(function(c, i) { return i < 3 ? Math.min(c + 16, 255) : c; })); } else if ((x == size - 1 || y == size - 1) && !(x == 0 || y == 0)) { that.pixel(xy[0] + x, xy[1] + y, rgba.map(function(c, i) { return i < 3 ? Math.max(c - 16, 0) : c; })); } else { that.pixel(xy[0] + x, xy[1] + y, rgba); } }); }); } }); that.context.putImageData(that.imageData, 0, 0); return that; } /*@ motionBlur Apply motion blur filter () -> The image object @*/ that.motionBlur = function() { return that.filter([ 0.2, 0.0, 0.0, 0.0, 0.0, 0.0, 0.2, 0.0, 0.0, 0.0, 0.0, 0.0, 0.2, 0.0, 0.0, 0.0, 0.0, 0.0, 0.2, 0.0, 0.0, 0.0, 0.0, 0.0, 0.2 ]); }; /*@ photocopy Apply photocopy filter () -> The image object @*/ that.photocopy = function(val) { return that.saturation(-1).depth(1).blur(1); }; /*@ pixel Get or set pixel values (x, y) -> <[n]> RGBA values (x, y, val) -> The image object x X coordinate y Y coordinate val <[n]> RGBA values @*/ that.pixel = function(x, y, val) { var i = getIndex(x, y); if (!val) { return Ox.range(4).map(function(c) { return self.data[i + c]; }); } else { val.forEach(function(v, c) { self.data[i + c] = v; }); } } /*@ posterize Apply posterize filter () -> The image object @*/ that.posterize = function() { return that.blur(3).map(function(rgba) { return [ Math.floor(rgba[0] / 64) * 64, Math.floor(rgba[1] / 64) * 64, Math.floor(rgba[2] / 64) * 64, rgba[3] ]; }); }; that.resize = function(width, height) { // fixme: may not work this way that.canvas.attr({ width: width, height: height }); return that; } /*@ saturation Apply saturation filter (val) -> The image object val Amount, from -1 (lowest) to 1 (highest) @*/ that.saturation = function(val) { return setSL('s', val); }; /*@ sharpen Apply sharpen filter () -> The image object @*/ that.sharpen = function(val) { return that.filter([ -1, -1, -1, -1, +9, -1, -1, -1, -1 ]); }; /*@ solarize Apply solarize filter () -> The image object @*/ that.solarize = function() { return that.map(function(rgba) { return [ rgba[0] < 128 ? rgba[0] : 255 - rgba[0], rgba[1] < 128 ? rgba[1] : 255 - rgba[1], rgba[2] < 128 ? rgba[2] : 255 - rgba[2], rgba[3] ]; }); } /*@ src Get or set the image source () -> Data URL (src) -> Image object, with new source src Image source (local, remote or data URL) @*/ that.src = function() { if (arguments.length == 0) { return that.canvas[0].toDataURL(); } else { var callback = arguments[1]; self.src = arguments[0]; self.image = new Image(); self.image.onload = function() { self.width = self.image.width; self.height = self.image.height; that.canvas.attr({ width: self.width, height: self.height }); that.context.drawImage(self.image, 0, 0); that.imageData = that.context.getImageData(0, 0, self.width, self.height); self.data = that.imageData.data; callback && callback(that); } self.image.src = self.src; return that; } }; }; callback(true); }