Android中怎么录制mp3格式文件，相信很多没有经验的人对此束手无策，为此本文总结了问题出现的原因和解决方法，通过这篇文章希望你能解决这个问题。
工具
MP3格式是用一个开源项目转的，MP3lame，由于该项目用到了jni，所以需要大家配置好ndk环境，环境配置在此就不多说了，大家可以自行百度，最新的应该很好配置。
创建jni
拷贝文件
下载好后（我下载的是3.98.4版本）打开，找到libmp3lame文件，将里面的.h和.c拷贝下来，在自己的工程里创建jni文件夹，在jni文件夹下新建一个文件夹（我的命名为lame-3.98.4_libmp3lame，后面会用到），将刚才拷贝的文件复制进去，然后再把include文件夹里的lame.h也拷贝进去。
创建Android.mk
在jni中创建文件，Android.mk
LOCAL_PATH := $(call my-dir)include $(CLEAR_VARS)LAME_LIBMP3_DIR := lame-3.98.4_libmp3lameLOCAL_MODULE := mp3lameLOCAL_SRC_FILES := $(LAME_LIBMP3_DIR)/bitstream.c $(LAME_LIBMP3_DIR)/fft.c $(LAME_LIBMP3_DIR)/id3tag.c $(LAME_LIBMP3_DIR)/mpglib_interface.c $(LAME_LIBMP3_DIR)/presets.c $(LAME_LIBMP3_DIR)/quantize.c $(LAME_LIBMP3_DIR)/reservoir.c $(LAME_LIBMP3_DIR)/tables.c $(LAME_LIBMP3_DIR)/util.c $(LAME_LIBMP3_DIR)/VbrTag.c $(LAME_LIBMP3_DIR)/encoder.c $(LAME_LIBMP3_DIR)/gain_analysis.c $(LAME_LIBMP3_DIR)/lame.c $(LAME_LIBMP3_DIR)/newmdct.c $(LAME_LIBMP3_DIR)/psymodel.c $(LAME_LIBMP3_DIR)/quantize_pvt.c $(LAME_LIBMP3_DIR)/set_get.c $(LAME_LIBMP3_DIR)/takehiro.c $(LAME_LIBMP3_DIR)/vbrquantize.c $(LAME_LIBMP3_DIR)/version.c com_maxi_mp3record_MP3Recorder.cinclude $(BUILD_SHARED_LIBRARY)**注意:**LAME_LIBMP3_DIR := lame-3.98.4_libmp3lame 需要将其改为你的项目中的文件名，即上面说的jni下新建的文件夹。
大家应该看到了最后一句的com_maxi_mp3record_MP3Recorder.c
很明显这是我自己创建的.c文件。用来调用mp3lame中的接口的，对应着我java中的com.maxi.mp3record.MP3Recorder.java。咱们先创建java文件。
创建MP3Recorder.java
对应你的包名建一个MP3Recorder.java文件，该文件是java文件对应你的包名建立即可。
package cn.ctvonline.android.modules.project.widget;import java.io.File;import java.io.FileNotFoundException;import java.io.FileOutputStream;import java.io.IOException;import android.media.AudioFormat;import android.media.AudioRecord;import android.media.MediaRecorder;import android.os.Handler;public class MP3Recorder { private String filePath; private int sampleRate; private boolean isRecording = false; private boolean isPause = false; private Handler handler; public static final int MSG_REC_STARTED = 1; public static final int MSG_REC_STOPPED = 2; public static final int MSG_REC_PAUSE = 3; public static final int MSG_REC_RESTORE = 4; public static final int MSG_ERROR_GET_MIN_BUFFERSIZE = -1; public static final int MSG_ERROR_CREATE_FILE = -2; public static final int MSG_ERROR_REC_START = -3; public static final int MSG_ERROR_AUDIO_RECORD = -4; public static final int MSG_ERROR_AUDIO_ENCODE = -5; public static final int MSG_ERROR_WRITE_FILE = -6; public static final int MSG_ERROR_CLOSE_FILE = -7; public MP3Recorder(int sampleRate) { this.sampleRate = sampleRate; } public void setFilePath(String filePath) { this.filePath = filePath; } public void start() { if (isRecording) { return; } new Thread() { @Override public void run() { android.os.Process .setThreadPriority(android.os.Process.THREAD_PRIORITY_URGENT_AUDIO); // 根据定义好的几个配置，来获取合适的缓冲大小 final int minBufferSize = AudioRecord.getMinBufferSize( sampleRate, AudioFormat.CHANNEL_IN_MONO, AudioFormat.ENCODING_PCM_16BIT); if (minBufferSize < 0) { if (handler != null) { handler.sendEmptyMessage(MSG_ERROR_GET_MIN_BUFFERSIZE); } return; } AudioRecord audioRecord = new AudioRecord( MediaRecorder.AudioSource.MIC, sampleRate, AudioFormat.CHANNEL_IN_MONO, AudioFormat.ENCODING_PCM_16BIT, minBufferSize * 2); // 5秒的缓冲 short[] buffer = new short[sampleRate * (16 / 8) * 1 * 5]; byte[] mp3buffer = new byte[(int) (7200 + buffer.length * 2 * 1.25)]; FileOutputStream output = null; try { File file = createSDFile(filePath); output = new FileOutputStream(file); } catch (FileNotFoundException e) { if (handler != null) { handler.sendEmptyMessage(MSG_ERROR_CREATE_FILE); } return; } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); } MP3Recorder.init(sampleRate, 1, sampleRate, 32); isRecording = true; // 录音状态 isPause = false; // 录音状态 try { try { audioRecord.startRecording(); // 开启录音获取音频数据 if (mListener != null) { mListener.wellPrepared(); } } catch (IllegalStateException e) { // 不给录音... if (handler != null) { handler.sendEmptyMessage(MSG_ERROR_REC_START); } return; } try { // 开始录音 if (handler != null) { handler.sendEmptyMessage(MSG_REC_STARTED); } int readSize = 0; boolean pause = false; while (isRecording) { if (isPause) { if (!pause) { handler.sendEmptyMessage(MSG_REC_PAUSE); pause = true; } continue; } if (pause) { handler.sendEmptyMessage(MSG_REC_RESTORE); pause = false; } readSize = audioRecord.read(buffer, 0, minBufferSize); voiceLevel = getVoiceSize(readSize, buffer); if (readSize < 0) { if (handler != null) { handler.sendEmptyMessage(MSG_ERROR_AUDIO_RECORD); } break; } else if (readSize == 0) { ; } else { int encResult = MP3Recorder.encode(buffer, buffer, readSize, mp3buffer); if (encResult < 0) { if (handler != null) { handler.sendEmptyMessage(MSG_ERROR_AUDIO_ENCODE); } break; } if (encResult != 0) { try { output.write(mp3buffer, 0, encResult); } catch (IOException e) { if (handler != null) { handler.sendEmptyMessage(MSG_ERROR_WRITE_FILE); } break; } } } } int flushResult = MP3Recorder.flush(mp3buffer); if (flushResult < 0) { if (handler != null) { handler.sendEmptyMessage(MSG_ERROR_AUDIO_ENCODE); } } if (flushResult != 0) { try { output.write(mp3buffer, 0, flushResult); } catch (IOException e) { if (handler != null) { handler.sendEmptyMessage(MSG_ERROR_WRITE_FILE); } } } try { output.close(); } catch (IOException e) { if (handler != null) { handler.sendEmptyMessage(MSG_ERROR_CLOSE_FILE); } } } finally { audioRecord.stop(); audioRecord.release(); } } finally { MP3Recorder.close(); isRecording = false; } if (handler != null) { handler.sendEmptyMessage(MSG_REC_STOPPED); } } }.start(); } public void stop() { isRecording = false; } public void pause() { isPause = true; } public void restore() { isPause = false; } public boolean isRecording() { return isRecording; } public boolean isPaus() { if (!isRecording) { return false; } return isPause; } // 获得声音的level public int getVoiceSize(int r, short[] buffer) { if (isRecording) { try { long v = 0; // 将 buffer 内容取出，进行平方和运算 for (int i = 0; i < buffer.length; i++) { v += buffer[i] * buffer[i]; } // 平方和除以数据总长度，得到音量大小。 double mean = v / (double) r; double volume = 10 * Math.log10(mean); return (((int) volume / 10) - 1); } catch (Exception e) { // TODO Auto-generated catch block } } return 1; } public static File createSDFile(String fileName) throws IOException { File file = new File(fileName); if (!isFileExists(file)) if (file.isDirectory()) { file.mkdirs(); } else { file.createNewFile(); } return file; } private int voiceLevel; public int getVoiceLevel() { return voiceLevel; } public interface AudioStageListener { void wellPrepared(); } public AudioStageListener mListener; public void setOnAudioStageListener(AudioStageListener listener) { mListener = listener; } public void setHandle(Handler handler) { this.handler = handler; } static { System.loadLibrary("mp3lame"); } public static void init(int inSamplerate, int outChannel, int outSamplerate, int outBitrate) { init(inSamplerate, outChannel, outSamplerate, outBitrate, 7); } public native static void init(int inSamplerate, int outChannel, int outSamplerate, int outBitrate, int quality); public native static int encode(short[] buffer_l, short[] buffer_r, int samples, byte[] mp3buf); public native static int flush(byte[] mp3buf); public native static void close();}创建c文件
在创建c文件，创建在jni下，命名就按你的java文件所在的包名命名”.”替换为“_”。例如：com_maxi_mp3record_MP3Recorder.c。当然还得有头文件：com_maxi_mp3record_MP3Recorder.h。
com_maxi_mp3record_MP3Recorder.c
#include "lame-3.98.4_libmp3lame/lame.h"#include "com_maxi_mp3record_MP3Recorder.h"static lame_global_flags *glf = NULL;JNIEXPORT void JNICALL Java_com_maxi_mp3record_MP3Recorder_init( JNIEnv *env, jclass cls, jint inSamplerate, jint outChannel, jint outSamplerate, jint outBitrate, jint quality) { if (glf != NULL) { lame_close(glf); glf = NULL; } glf = lame_init(); lame_set_in_samplerate(glf, inSamplerate); lame_set_num_channels(glf, outChannel); lame_set_out_samplerate(glf, outSamplerate); lame_set_brate(glf, outBitrate); lame_set_quality(glf, quality); lame_init_params(glf);}JNIEXPORT jint JNICALL Java_com_maxi_mp3record_MP3Recorder_encode( JNIEnv *env, jclass cls, jshortArray buffer_l, jshortArray buffer_r, jint samples, jbyteArray mp3buf) { jshort* j_buffer_l = (*env)->GetShortArrayElements(env, buffer_l, NULL); jshort* j_buffer_r = (*env)->GetShortArrayElements(env, buffer_r, NULL); const jsize mp3buf_size = (*env)->GetArrayLength(env, mp3buf); jbyte* j_mp3buf = (*env)->GetByteArrayElements(env, mp3buf, NULL); int result = lame_encode_buffer(glf, j_buffer_l, j_buffer_r, samples, j_mp3buf, mp3buf_size); (*env)->ReleaseShortArrayElements(env, buffer_l, j_buffer_l, 0); (*env)->ReleaseShortArrayElements(env, buffer_r, j_buffer_r, 0); (*env)->ReleaseByteArrayElements(env, mp3buf, j_mp3buf, 0); return result;}JNIEXPORT jint JNICALL Java_com_maxi_mp3record_MP3Recorder_flush( JNIEnv *env, jclass cls, jbyteArray mp3buf) { const jsize mp3buf_size = (*env)->GetArrayLength(env, mp3buf); jbyte* j_mp3buf = (*env)->GetByteArrayElements(env, mp3buf, NULL); int result = lame_encode_flush(glf, j_mp3buf, mp3buf_size); (*env)->ReleaseByteArrayElements(env, mp3buf, j_mp3buf, 0); return result;}JNIEXPORT void JNICALL Java_com_maxi_mp3record_MP3Recorder_close( JNIEnv *env, jclass cls) { lame_close(glf); glf = NULL;}com_maxi_mp3record_MP3Recorder.h
#include <jni.h>#ifndef _Included_com_maxi_mp3record_MP3Recorder#define _Included_com_maxi_mp3record_MP3Recorder#ifdef __cplusplusextern "C" {#endifJNIEXPORT void JNICALL Java_com_maxi_mp3record_MP3Recorder_init (JNIEnv *, jclass, jint, jint, jint, jint, jint);JNIEXPORT jint JNICALL Java_com_maxi_mp3record_MP3Recorder_encode (JNIEnv *, jclass, jshortArray, jshortArray, jint, jbyteArray);JNIEXPORT jint JNICALL Java_com_maxi_mp3record_MP3Recorder_flush (JNIEnv *, jclass, jbyteArray);JNIEXPORT void JNICALL Java_com_maxi_mp3record_MP3Recorder_close (JNIEnv *, jclass);#ifdef __cplusplus}#endif#endif这俩文件别只复制不看内容啊，里面可都是连接java和c的接口，所以不能有差错。举个例子吧，#ifndef _Included_com_maxi_mp3record_MP3Recorder，这个就得替换成你对应的包名，里面所有都得替换成你自己的程序对应的包名。
编译ndk
创建Application.mk在你的项目文件的jni下，在里面写入:
APP_ABI := all
如果不加，NDK只会编译“armeabi”,然而安卓有很多不同类型的处理器，所以我们不止需要arm。相信你们搞到现在了肯定ndk都配置好了，然后打开终端，进入到你的项目（找到你的ndk目录下的ndk-bulid,最好把它添加到环境变量里，对于以后编译比较方便，在此默认你没添加环境变量），执行ndk-bulid。稍等片刻你会发现你的项目里多了一个obj文件夹，obj文件夹下会生成”arm64-v8a”、”armeabi”、”armeabi-v7a”、”mips”、”mips64”、”x86”、”x86_64”。打开它，各个文件夹下会有一个libmp3lame.so。ok，没错那就是你要的“滑板鞋”。将它放入你的libs文件下，没有自行创建，各个平台便都可以加载了。
使用方法
MP3Recorder recorder = new MP3Recorder(8000);recorder.setFilePath(voicePath);//录音保存目录recorder.start();//开始录音recorder.stop();//录音结束recorder.getVoiceLevel()//这是我封装的获取音频振幅接口，大家可以用来录音的时候显示声音大小，数据自行调节。看完上述内容，你们掌握Android中怎么录制mp3格式文件的方法了吗？如果还想学到更多技能或想了解更多相关内容，欢迎关注编程网行业资讯频道，感谢各位的阅读！
