html5+js 進行錄音，

最近在寫一個純html5+js的移動端app，客戶提出即時通訊功能還要發送語音，整整花費了一個星期的時間，終於能在android上邊進行錄音，廢話不多說了，上代碼。。。。。。。。

錄音的代碼使用的HZRecorder.js, 註釋已經很詳細了，播放、停止這些直接調用就可以了

(function (window) {
    //兼容
    window.URL = window.URL || window.webkitURL;
    navigator.getUserMedia = navigator.getUserMedia || navigator.webkitGetUserMedia || navigator.mozGetUserMedia || navigator.msGetUserMedia;

    var HZRecorder = function (stream, config) {
        config = config || {};
        config.sampleBits = config.sampleBits || 8;      //採樣數位 8, 16
        config.sampleRate = config.sampleRate || (44100 / 6);   //採樣率(1/6 44100)

        var context = new (window.webkitAudioContext || window.AudioContext)();
        var audioInput = context.createMediaStreamSource(stream);
        var createScript = context.createScriptProcessor || context.createJavaScriptNode;
        var recorder = createScript.apply(context, [4096, 1, 1]);

        var audioData = {
            size: 0          //錄音文件長度
            , buffer: []     //錄音緩存
            , inputSampleRate: context.sampleRate    //輸入採樣率
            , inputSampleBits: 16       //輸入採樣數位 8, 16
            , outputSampleRate: config.sampleRate    //輸出採樣率
            , oututSampleBits: config.sampleBits       //輸出採樣數位 8, 16
            , input: function (data) {
                this.buffer.push(new Float32Array(data));
                this.size += data.length;
            }
            , compress: function () { //合併壓縮
                //合併
                var data = new Float32Array(this.size);
                var offset = 0;
                for (var i = 0; i < this.buffer.length; i++) {
                    data.set(this.buffer[i], offset);
                    offset += this.buffer[i].length;
                }
                //壓縮
                var compression = parseInt(this.inputSampleRate / this.outputSampleRate);
                var length = data.length / compression;
                var result = new Float32Array(length);
                var index = 0, j = 0;
                while (index < length) {
                    result[index] = data[j];
                    j += compression;
                    index++;
                }
                return result;
            }
            , encodeWAV: function () {
                var sampleRate = Math.min(this.inputSampleRate, this.outputSampleRate);
                var sampleBits = Math.min(this.inputSampleBits, this.oututSampleBits);
                var bytes = this.compress();
                var dataLength = bytes.length * (sampleBits / 8);
                var buffer = new ArrayBuffer(44 + dataLength);
                var data = new DataView(buffer);

                var channelCount = 1;//單聲道
                var offset = 0;

                var writeString = function (str) {
                    for (var i = 0; i < str.length; i++) {
                        data.setUint8(offset + i, str.charCodeAt(i));
                    }
                }

                // 資源交換文件標識符 
                writeString('RIFF'); offset += 4;
                // 下個地址開始到文件尾總字節數,即文件大小-8 
                data.setUint32(offset, 36 + dataLength, true); offset += 4;
                // WAV文件標誌
                writeString('WAVE'); offset += 4;
                // 波形格式標誌 
                writeString('fmt '); offset += 4;
                // 過濾字節,一般爲 0x10 = 16 
                data.setUint32(offset, 16, true); offset += 4;
                // 格式類別 (PCM形式採樣數據) 
                data.setUint16(offset, 1, true); offset += 2;
                // 通道數 
                data.setUint16(offset, channelCount, true); offset += 2;
                // 採樣率,每秒樣本數,表示每個通道的播放速度 
                data.setUint32(offset, sampleRate, true); offset += 4;
                // 波形數據傳輸率 (每秒平均字節數) 單聲道×每秒數據位數×每樣本數據位/8 
                data.setUint32(offset, channelCount * sampleRate * (sampleBits / 8), true); offset += 4;
                // 快數據調整數 採樣一次佔用字節數 單聲道×每樣本的數據位數/8 
                data.setUint16(offset, channelCount * (sampleBits / 8), true); offset += 2;
                // 每樣本數據位數 
                data.setUint16(offset, sampleBits, true); offset += 2;
                // 數據標識符 
                writeString('data'); offset += 4;
                // 採樣數據總數,即數據總大小-44 
                data.setUint32(offset, dataLength, true); offset += 4;
                // 寫入採樣數據 
                if (sampleBits === 8) {
                    for (var i = 0; i < bytes.length; i++, offset++) {
                        var s = Math.max(-1, Math.min(1, bytes[i]));
                        var val = s < 0 ? s * 0x8000 : s * 0x7FFF;
                        val = parseInt(255 / (65535 / (val + 32768)));
                        data.setInt8(offset, val, true);
                    }
                } else {
                    for (var i = 0; i < bytes.length; i++, offset += 2) {
                        var s = Math.max(-1, Math.min(1, bytes[i]));
                        data.setInt16(offset, s < 0 ? s * 0x8000 : s * 0x7FFF, true);
                    }
                }

                return new Blob([data], { type: 'audio/mp3' });
            }
        };

        //開始錄音
        this.start = function () {
            audioInput.connect(recorder);
            recorder.connect(context.destination);
        }

        //停止
        this.stop = function () {

            recorder.disconnect();
        }

        //獲取音頻文件
        this.getBlob = function () {
            this.stop();
            return audioData.encodeWAV();
        }

        //回放
        this.play = function (audio) {
            var downRec = document.getElementById("downloadRec");
            downRec.href = window.URL.createObjectURL(this.getBlob());
            downRec.download = new Date().toLocaleString()+".mp3";
            audio.src = window.URL.createObjectURL(this.getBlob());
        }

        //上傳
        this.upload = function (url, callback) {
            var fd = new FormData();
            fd.append("audioData", this.getBlob());
            var xhr = new XMLHttpRequest();
            if (callback) {
                xhr.upload.addEventListener("progress", function (e) {
                    callback('uploading', e);
                }, false);
                xhr.addEventListener("load", function (e) {
                    callback('ok', e);
                }, false);
                xhr.addEventListener("error", function (e) {
                    callback('error', e);
                }, false);
                xhr.addEventListener("abort", function (e) {
                    callback('cancel', e);
                }, false);
            }
            xhr.open("POST", url);
            xhr.send(fd);
        }

        //音頻採集
        recorder.onaudioprocess = function (e) {
            audioData.input(e.inputBuffer.getChannelData(0));
            //record(e.inputBuffer.getChannelData(0));
        }

    };
    //拋出異常
    HZRecorder.throwError = function (message) {
        alert(message);
        throw new function () { this.toString = function () { return message; } }
    }
    //是否支持錄音
    HZRecorder.canRecording = (navigator.getUserMedia != null);
    //獲取錄音機
    HZRecorder.get = function (callback, config) {
        if (callback) {
            if (navigator.getUserMedia) {
                navigator.getUserMedia(
                    { audio: true } //只啓用音頻
                    , function (stream) {
                        var rec = new HZRecorder(stream, config);
                        callback(rec);
                    }
                    , function (error) {
                        switch (error.code || error.name) {
                            case 'PERMISSION_DENIED':
                            case 'PermissionDeniedError':
                                HZRecorder.throwError('用戶拒絕提供信息。');
                                break;
                            case 'NOT_SUPPORTED_ERROR':
                            case 'NotSupportedError':
                                HZRecorder.throwError('瀏覽器不支持硬件設備。');
                                break;
                            case 'MANDATORY_UNSATISFIED_ERROR':
                            case 'MandatoryUnsatisfiedError':
                                HZRecorder.throwError('無法發現指定的硬件設備。');
                                break;
                            default:
                                HZRecorder.throwError('無法打開麥克風。異常信息:' + (error.code || error.name));
                                break;
                        }
                    });
            } else {
                HZRecorder.throwErr('當前瀏覽器不支持錄音功能。'); return;
            }
        }
    }

    window.HZRecorder = HZRecorder;

})(window);

 中間有我自己調試的代碼，原來的使用的wav格式的音頻，如果使用wav只需把MP3換成wav就可以使用了。

html頁面

<!DOCTYPE html>
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
    <meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
    <title></title>
</head>
<body>
    <div>
        <audio controls autoplay></audio>
        <input onclick="startRecording()" type="button" value="錄音" />
        <input onclick="stopRecording()"  type="button" value="停止" />
        <input onclick="playRecording()" type="button" value="播放" />
        <a href="" click="" download="">下載</a>
    </div>

    <script type="text/javascript" src="HZRecorder.js"></script>


    <script>

        var recorder;

        var audio = document.querySelector('audio');

        function startRecording() {
            HZRecorder.get(function (rec) {
                recorder = rec;
                recorder.start();
            });
        }

        function stopRecording() {
            recorder.stop();
        }

        function playRecording() {
            recorder.play(audio);
        }

  
    </script>

</body>
</html>

在電腦使用瀏覽器就可以直接錄音了

效果如上，我的瀏覽器錄音的時候會出現一個紅點。

當部署到android的時候應該是需要添加一個權限在AndroidManifest.xml中

<!-- 使用麥克風的權限 -->
<uses-permission android:name="android.permission.RECORD_AUDIO"/>

大概就是這樣子的。