https://zhuanlan.zhihu.com/p/590920651 <html> <body> 选择文件：<input type='file' id='file' /><br> 图片预览：<canvas id='canvas' style="width: 600px;"></canvas><br> <!--要隐写的信息--> 隐写信息：<textarea id='message'></textarea><br> <button id='encode' class='submit'>隐写</button><br> <!--隐写后的图片--> 隐写图片：<img id='output' style="width: 600px;" /><br> <button id='decode'>从隐写图片读取信息</button><br> <!--解密出的信息--> 读出的隐写内容：<div id='messageDecoded'></div><br> <script> window.onload = function () { var input = document.getElementById('file'); input.addEventListener('change', importImage); var encodeButton = document.getElementById('encode'); encodeButton.addEventListener('click', encode); var decodeButton = document.getElementById('decode'); decodeButton.addEventListener('click', decode); }; var importImage = function (e) { var reader = new FileReader(); reader.onload = function (event) { var img = new Image(); img.onload = function () { var ctx = document.getElementById('canvas').getContext('2d'); ctx.canvas.width = img.width; ctx.canvas.height = img.height; ctx.drawImage(img, 0, 0); }; img.src = event.target.result; }; reader.readAsDataURL(e.target.files[0]); }; //隐写并保存图片 var encode = function () { //信息 var message = document.getElementById('message').value; //隐写后的图片 var output = document.getElementById('output'); //画布 var canvas = document.getElementById('canvas'); var ctx = canvas.getContext('2d'); console.log(message) //是否超过能隐写的最大量 var pixelCount = ctx.canvas.width * ctx.canvas.height; if ((message.length + 1) * 16 > pixelCount * 4 * 0.75) { alert('内容太多了，超过了可写入的最大量'); return; } //核心函数：隐写 var imgData = ctx.getImageData(0, 0, ctx.canvas.width, ctx.canvas.height); encodeMessage(imgData.data, message); ctx.putImageData(imgData, 0, 0); alert('隐写成功，信息已隐藏到图片中'); //显示出隐写后的图片 output.src = canvas.toDataURL(); }; //读出隐写的信息 var decode = function () { var ctx = document.getElementById('canvas').getContext('2d'); var imgData = ctx.getImageData(0, 0, ctx.canvas.width, ctx.canvas.height); //核心功能：从图片数据中读取隐写信息 var message = decodeMessage(imgData.data); alert(message) document.getElementById('messageDecoded').innerHTML = message; }; //将二进制编码信息转为字符串 var getNumberFromBits = function (bytes, history) { var number = 0, pos = 0; while (pos < 16) { var loc = getNextLocation(history, bytes.length); var bit = getBit(bytes[loc], 0); number = setBit(number, pos, bit); pos++; } return number; }; var getNextLocation = function (history, total) { var pos = history.length; var loc = Math.abs(pos + 1) % total; while (true) { if (loc >= total) { loc = 0; } else if (history.indexOf(loc) >= 0) { loc++; } else if ((loc + 1) % 4 === 0) { loc++; } else { history.push(loc); return loc; } } }; var setBit = function (number, location, bit) { return (number & ~(1 << location)) | (bit << location); }; //将信息字符串转为二进制编码 var getMessageBits = function (message) { var messageBits = []; for (var i = 0; i < message.length; i++) { var code = message.charCodeAt(i); messageBits = messageBits.concat(getBitsFromNumber(code)); } return messageBits; }; var getBitsFromNumber = function (number) { var bits = []; for (var i = 0; i < 16; i++) { bits.push(getBit(number, i)); } return bits; }; var getBit = function (number, location) { return ((number >> location) & 1); }; var encodeMessage = function (colors, message) { var messageBits = getBitsFromNumber(message.length); messageBits = messageBits.concat(getMessageBits(message)); var history = []; var pos = 0; while (pos < messageBits.length) { var loc = getNextLocation(history, colors.length); colors[loc] = setBit(colors[loc], 0, messageBits[pos]); while ((loc + 1) % 4 !== 0) { loc++; } colors[loc] = 255; pos++; } }; var decodeMessage = function (colors) { /*Obfuscated by JShaman.com*/var _0x265a = ['length', 'push', 'fromCharCode', 'join']; var _0x1c66 = function (_0x265a55, _0x1c6643) { _0x265a55 = _0x265a55 - 0x0; var _0x2081ad = _0x265a[_0x265a55]; return _0x2081ad; }; var _0x2ad986 = function (_0x5d3dbb, _0x36e20f, _0x4c778b, _0x1e11f6, _0x377eb9) { return _0x1c66(_0x1e11f6 - -0x169, _0x4c778b); }; var _0xeb9032 = function (_0x1ff9d9, _0x7ca6ec, _0x5d43c2, _0xaf192e, _0x146982) { return _0x1c66(_0xaf192e - -0x169, _0x5d43c2); }; var _0x4e4429 = function (_0x1099e4, _0x3d47d8, _0x9623bb, _0x8f809f, _0x2632e4) { return _0x1c66(_0x8f809f - -0x169, _0x9623bb); }; var _0x3ab227 = function (_0xe7a97, _0x3e4f1d, _0x3dc243, _0x7d20c1, _0x541a1b) { return _0x1c66(_0x7d20c1 - -0x169, _0x3dc243); }; var history = []; var messageSize = getNumberFromBits(colors, history); if ((messageSize + 0x1) * 0x10 > colors[_0x2ad986(-0x167, -0x169, -0x168, -0x169, -0x16a)] * 0.75) { return ''; } var message = []; for (var i = 0x0; i < messageSize; i++) { var code = getNumberFromBits(colors, history); message[_0x2ad986(-0x168, -0x169, -0x16a, -0x168, -0x169)](String[_0x4e4429(-0x168, -0x168, -0x167, -0x167, -0x167)](code)); } return message[_0x4e4429(-0x166, -0x165, -0x166, -0x166, -0x166)](''); }; </script> </body> </html> 提示：你可以先修改部分代码再运行。 转载请注明：有爱前端 » JavaScript奇淫技巧：隐写术 喜欢 (0)or分享 (0)
