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Web 播放声音
- WBOYasal
- 2016-06-24 11:25:454650semak imbas
本文主要介绍 AMR(Aduio) 播放 AMR 格式 Base64码 音频。
1、必备资料 github AMR 开源库 ：https://github.com/jpemartins/amr.js 用心把这个项目看一遍，对于我下面说的话，可以忽略啦，代码是最好的文章，哈哈~~
2、核心 JS 库 ：amr.js 、pcmdata.min.js、libamr-nb.js (g上述ithub项目中有另外三个js，我给合成一个amr.js，不要混乱)这三个 JS 是播放声音的主要依赖，下面一 一 介绍下：
① amr.js : 可以理解成 “桥” 的概念，连接底层解码和客户端调用的桥梁。
② pcmdata.min.js : 封装 pcm data， PCM是一种编码格式 ， PCM 添加上 RIFF 头 可以组成 Wave 音频(Wave 不止这一种编码方式)，细节太深，小弟也不懂啦~~,有空深 挖。
③ libamr-nb.js : amr转换的核心库，这个文件比较大，压缩后大概也要 600kb 左右。
④ 如果下载三个核心库，建议从上篇 “Web 播放声音 — 介绍篇” 中的附件中卸载，在 github 现在的核心库，在 Chrome 下只能播放一次，把这个问题修复了一下，原因是 以同样的 Audio.src 创建 Audio 在 Chrome 下就不能二次播放，网上说法各异，最终自己动手解决了，详细可以在 amr.js 中的 global.util.play 方法中看。
3、具体用法
说了有一阵子白话了，该上点代码了，下面是我封装的播放 AMR 格式 Base64 码 的插件，直接在页面引用可以 ，下载地址可以在 “Web 播放声音 — 介绍篇” 下载。
页面一点样式都没有加，只有两个按钮，小伙伴凑合凑合,哈哈~~
代码中只引入了 voice.js 一个 js,其他 js 动态引用了。（公司有 cdn 所以直接放在上面了）。
步骤：
第一步：执行初始化。
第二步：调用相应方法。
<!DOCTYPE html><html><head lang="en"> <meta charset="UTF-8"> <title>Example</title><script src="js/voice.js"></script></head><body><input type="button" value="play" id="playId"/><input type="button" value="stop" id="stopId"/></body><script type="text/javascript"><br /><br />//初始化RongIMLib.RongIMVoice.init();<br />
//播放
document.getElementById("playId").onclick = function(){<br /> // base64Str ： amr 格式的 base64 码，可以用 HTML5 FileReader 或者canvas 进行转换 。 <br /> var base64Str = "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"; RongIMLib.RongIMVoice.play(base64Str );};<br /> //暂停
document.getElementById("stopId").onclick = function(){ RongIMLib.RongIMVoice.stop(); }; <br /><br /></script> <br /><br /></html> 在这里也把 "voice.js" 的代码贴出来，使用 typescript 写完后生成出来的，方便小伙伴们查看：
var RongIMLib;(function (RongIMLib) { var RongIMVoice = (function () { function RongIMVoice() { } /** * 初始化声音库 */ RongIMVoice.init = function () { if (this.isIE) { var div = document.createElement("div"); div.setAttribute("id", "flashContent"); document.body.appendChild(div); var script = document.createElement("script"); script.src = "http://cdn.ronghub.com/swfobject-2.0.0.min.js"; var header = document.getElementsByTagName("head")[0]; header.appendChild(script); setTimeout(function () { var swfVersionStr = "11.4.0"; var flashvars = {}; var params = {}; params.quality = "high"; params.bgcolor = "#ffffff"; params.allowscriptaccess = "always"; params.allowfullscreen = "true"; var attributes = {}; attributes.id = "player"; attributes.name = "player"; attributes.align = "middle"; swfobject.embedSWF("http://cdn.ronghub.com/player-2.0.2.swf", "flashContent", "1", "1", swfVersionStr, null, flashvars, params, attributes); }, 200); } else { var list = ["http://cdn.ronghub.com/pcmdata-2.0.0.min.js", "http://cdn.ronghub.com/libamr-2.0.1.min.js"]; for (var i = 0, len = list.length; i < len; i++) { var script = document.createElement("script"); script.src = list[i]; document.head.appendChild(script); } } this.isInit = true; }; /** * 开始播放声音 * @param data {string} amr 格式的 base64 码 * @param duration {number} 播放大概时长 用 data.length / 1024 */ RongIMVoice.play = function (data, duration) { this.checkInit("play"); var me = this; if (me.isIE) { me.thisMovie().doAction("init", data); } else { me.palyVoice(data); me.onCompleted(duration); } }; /** * 停止播放声音 */ RongIMVoice.stop = function () { this.checkInit("stop"); var me = this; if (me.isIE) { me.thisMovie().doAction("stop"); } else { if (me.element) { me.element.stop(); } } }; /** * 播放声音时调用的方法 */ RongIMVoice.onprogress = function () { this.checkInit("onprogress"); };<br /> /** <br /> * 校验是否初始化<br /> */ RongIMVoice.checkInit = function (postion) { if (!this.isInit) { throw new Error("RongIMVoice not initialized,postion:" + postion); } }; RongIMVoice.thisMovie = function () { return eval("window['player']"); }; RongIMVoice.onCompleted = function (duration) { var me = this; var count = 0; var timer = setInterval(function () { count++; me.onprogress(); if (count >= duration) { clearInterval(timer); } }, 1000); if (me.isIE) { me.thisMovie().doAction("play"); } }; RongIMVoice.base64ToBlob = function (base64Data, type) { var mimeType; if (type) { mimeType = { type: type }; } base64Data = base64Data.replace(/^(.*)[,]/, ''); var sliceSize = 1024; var byteCharacters = atob(base64Data); var bytesLength = byteCharacters.length; var slicesCount = Math.ceil(bytesLength / sliceSize); var byteArrays = new Array(slicesCount); for (var sliceIndex = 0; sliceIndex < slicesCount; ++sliceIndex) { var begin = sliceIndex * sliceSize; var end = Math.min(begin + sliceSize, bytesLength); var bytes = new Array(end - begin); for (var offset = begin, i = 0; offset < end; ++i, ++offset) { bytes[i] = byteCharacters[offset].charCodeAt(0); } byteArrays[sliceIndex] = new Uint8Array(bytes); } return new Blob(byteArrays, mimeType); }; RongIMVoice.palyVoice = function (base64Data) { var reader = new FileReader(), blob = this.base64ToBlob(base64Data, "audio/amr"), me = this; reader.onload = function () { var samples = new AMR({ benchmark: true }).decode(reader.result); me.element = AMR.util.play(samples); }; reader.readAsBinaryString(blob); }; RongIMVoice.isIE = /Trident/.test(navigator.userAgent); RongIMVoice.isInit = false; return RongIMVoice; })(); RongIMLib.RongIMVoice = RongIMVoice; //兼容AMD CMD if ("function" === typeof require && "object" === typeof module && module && module.id && "object" === typeof exports && exports) { module.exports = RongIMVoice; } else if ("function" === typeof define && define.amd) { define("RongIMVoice", [], function () { return RongIMVoice; }); }})(RongIMLib || (RongIMLib = {})); 好啦，到此本文结束，会尽快更新 Flash 下播放 AMR 格式 Base64 码，代码中哪里有错误或者有异议麻烦小伙伴们联系我，一起讨论，有则改之无法加冕，一起进步，thx~~。
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