android - 如何在本机 C++ 中使用 AudioRecord 类录制音频

Question

我曾经AudioRecord录制音频，以下是我的代码：

#include<stdio.h>
#include<stdlib.h>
#include <media/AudioRecord.h>
 using namespace android;
//==============================================
//  Audio Record Defination
//==============================================
 
static pthread_t        g_AudioRecordThread;
static pthread_t *  g_AudioRecordThreadPtr = NULL;
 
volatile bool   g_bQuitAudioRecordThread = false;
volatile int    g_iInSampleTime = 0;
int     g_iNotificationPeriodInFrames = 8000/10; 
// g_iNotificationPeriodInFrames should be change when sample rate changes.
 
static void *   AudioRecordThread( void *inArg );
 
void AudioRecordCallback(int event, void* user, void *info)
{
    if(event == android::AudioRecord::EVENT_NEW_POS)
    {
        g_iInSampleTime += g_iNotificationPeriodInFrames;       
        //if(g_iInSampleTime > g_iNotificationPeriodInFrames*100) 
        //      g_bQuitAudioRecordThread = true;
    }
    else if (event == android::AudioRecord::EVENT_MORE_DATA)
    {       
        android::AudioRecord::Buffer* pBuff = (android::AudioRecord::Buffer*)info;
            pBuff->size = 0;
    }
    else if (event == android::AudioRecord::EVENT_OVERRUN)
    {
        //LOGE(" EVENT_OVERRUN \n");
        printf("[%d%s]EVENT_OVERRUN \n",__LINE__,__FUNCTION__);
    }
}
 
static void *   AudioRecordThread( void *inArg )
{
    uint64_t                        inHostTime              = 0;
    void *                              inBuffer                    = NULL; 
    audio_source_t              inputSource             = AUDIO_SOURCE_MIC;
    audio_format_t              audioFormat             = AUDIO_FORMAT_PCM_16_BIT;  
    audio_channel_mask_t    channelConfig       = AUDIO_CHANNEL_IN_MONO; //AUDIO_CHANNEL_IN_STEREO; 
    int                                     bufferSizeInBytes = 1600;
    int                                     sampleRateInHz      = 8000; 
    android::AudioRecord *  pAudioRecord        = NULL;
    FILE *                                  g_pAudioRecordFile      = NULL;
    //char                                      strAudioFile[]              = "/mnt/sdcard/external_sd/AudioRecordFile.pcm";
    char                                        strAudioFile[]              = "./AudioRecordFile.pcm";
 
    int iNbChannels         = 1;    // 1 channel for mono, 2 channel for streo
    int iBytesPerSample = 2;    // 16bits pcm, 2Bytes
    int frameSize           = 0;    // frameSize = iNbChannels * iBytesPerSample
    //int minFrameCount     = 0;    // get from AudroRecord object
    size_t minFrameCount    = 0;    // get from AudroRecord object
    int iWriteDataCount = 0;    // how many data are there write to file
    printf("[%d%s]thread enter ok!\n",__LINE__,__FUNCTION__);
 
    
    String16 pack_name("wang_test");
    
 
    printf("[%d%s]thread enter ok!\n",__LINE__,__FUNCTION__);
    
#if 1
    // log the thread id for debug info
    //LOGD("%s  Thread ID  = %d  \n", __FUNCTION__,  pthread_self());  
    printf("[%d%s]  Thread ID  = %d  \n", __LINE__,__FUNCTION__,  pthread_self());
    g_iInSampleTime = 0;
    g_pAudioRecordFile = fopen(strAudioFile, "wb+");    
    if(g_pAudioRecordFile == NULL)
    {
        printf("open file erro !\n");
    }
    
    iNbChannels = (channelConfig == AUDIO_CHANNEL_IN_STEREO) ? 2 : 1;
    frameSize   = iNbChannels * iBytesPerSample;    
 
    android::status_t   status = android::AudioRecord::getMinFrameCount(
        &minFrameCount, sampleRateInHz, audioFormat, channelConfig);    
    
    if(status != android::NO_ERROR)
    {
        //LOGE("%s  AudioRecord.getMinFrameCount fail \n", __FUNCTION__);
        printf("[%d%s]AudioRecord.getMinFrameCount fail \n",__LINE__,__FUNCTION__);
        goto exit ;
    }
    
    //LOGE("sampleRateInHz = %d minFrameCount = %d iNbChannels = %d frameSize = %d ", 
    //  sampleRateInHz, minFrameCount, iNbChannels, frameSize); 
    printf("[%d%s]sampleRateInHz = %d minFrameCount = %d iNbChannels = %d frameSize = %d \n", 
        __LINE__,__FUNCTION__,sampleRateInHz, minFrameCount, iNbChannels, frameSize);
    
    bufferSizeInBytes = minFrameCount * frameSize;
    
    inBuffer = malloc(bufferSizeInBytes); 
    if(inBuffer == NULL)
    {       
        //LOGE("%s  alloc mem failed \n", __FUNCTION__);        
        printf("[%d%s]  alloc mem failed \n",__LINE__, __FUNCTION__);
        goto exit ; 
    }
 
    g_iNotificationPeriodInFrames = sampleRateInHz/10;  
    
    
    
    pAudioRecord  = new android::AudioRecord(pack_name);
    if(NULL == pAudioRecord)
    {
        //LOGE(" create native AudioRecord failed! ");
        printf(" [%d%s] create native AudioRecord failed! \n",__LINE__,__FUNCTION__);
        goto exit;
    }
    
    pAudioRecord->set( inputSource,
                                    sampleRateInHz,
                                    audioFormat,
                                    channelConfig,
                                    0,
                                    AudioRecordCallback,
                                    NULL,
                                    0,
                                    true); 
 
    if(pAudioRecord->initCheck() != android::NO_ERROR)  
    {
        //LOGE("AudioTrack initCheck error!");
        printf("[%d%s]AudioTrack initCheck error!\n",__LINE__,__FUNCTION__);
        goto exit;
    }
 
    if(pAudioRecord->setPositionUpdatePeriod(g_iNotificationPeriodInFrames) != android::NO_ERROR)
    {
        //LOGE("AudioTrack setPositionUpdatePeriod error!");
        printf("[%d%s]AudioTrack setPositionUpdatePeriod error!\n",__LINE__,__FUNCTION__);
        goto exit;
    }
    
    if(pAudioRecord->start()!= android::NO_ERROR)
    {
        //LOGE("AudioTrack start error!");
        printf("[%d%s]AudioTrack start error!\n",__LINE__,__FUNCTION__);
        goto exit;
    }   
    
    while (!g_bQuitAudioRecordThread)
    {
        //inHostTime = UpTicks();
        int readLen = pAudioRecord->read(inBuffer, bufferSizeInBytes);      
        int writeResult = -1;
        
        if(readLen > 0) 
        {
            iWriteDataCount += readLen;
            if(NULL != g_pAudioRecordFile)
            {
                writeResult = fwrite(inBuffer, 1, readLen, g_pAudioRecordFile);             
                if(writeResult < readLen)
                {
                    //LOGE("Write Audio Record Stream error");
                    printf("[%d%s]Write Audio Record Stream error\n",__LINE__,__FUNCTION__);
                }
            }           
 
            // write PCM data to file or other stream,implement it yourself
            //writeResult = WriteAudioData(                 
            //      g_iInSampleTime, 
            //      inHostTime, 
            //      inBuffer, 
            //      readLen);
            //LOGD("readLen = %d  writeResult = %d  iWriteDataCount = %d", readLen, writeResult, iWriteDataCount);          
        }
        else 
        {
            //LOGE("pAudioRecord->read  readLen = 0");
            printf("[%d%s]pAudioRecord->read  readLen = 0\n",__LINE__,__FUNCTION__);
        }
    }
 
        
    exit:
 
    if(NULL != g_pAudioRecordFile)
    {
        fflush(g_pAudioRecordFile);
        fclose(g_pAudioRecordFile);
        g_pAudioRecordFile = NULL;
    }
 
    if(pAudioRecord)
    {
        pAudioRecord->stop();
        //delete pAudioRecord;
        pAudioRecord == NULL;
    }
 
    if(inBuffer)
    {
        free(inBuffer);
        inBuffer = NULL;
    }
#endif
    //LOGD("%s  Thread ID  = %d  quit\n", __FUNCTION__,  pthread_self());
    printf("[%d%s] Thread ID  = %d  quit\n", __LINE__,__FUNCTION__,  pthread_self());
    return NULL;
    
}
 
int main()
{
    printf("hello world! \n");  
    pthread_t record_pid ;
    if(pthread_create(&record_pid,NULL,AudioRecordThread,NULL)<0)
    {
        printf("%d%s pthread create erro !\n",__LINE__,__FUNCTION__);
    }
    
    while(1)
    {
        
    }
    return 0;
}

我将可执行文件推送到/data目录下。运行后，我得到 pcm 文件。我用Cool Pro Edit软件播放，但我什么也听不见。

标签： androidc++android-ndk