ios - objective-c 中的音频文件格式问题

Question

我使用 AVAudioRecorder 编写了一个音频 WAV(录制了我的声音)文件。最终的文件格式是 WAV 文件。文件已成功保存，我可以听到自己的声音。我想将此文件发送到后端服务器(网络服务)。但是我的服务器只接受 WAV 格式的数据和 FMT 信息。它不接受我的 wav 文件，因为我的 wav 文件信息包含 FLLR、数据、FMT。我已经在 Riffpad 工具中检查了我的 WAV 文件信息。它显示 FLLR、数据、FMT。但我只想要数据和 fmt。因为我的服务器端只接受数据和 FMT。那么请建议如何以编程方式删除我的 wav 文件中的 FLLR？

我的记录源代码:

  NSError *error;

    // Recording settings
    NSMutableDictionary *settings = [NSMutableDictionary dictionary];
    [settings setValue: [NSNumber numberWithInt:kAudioFormatLinearPCM] forKey:AVFormatIDKey];
    [settings setValue: [NSNumber numberWithFloat:22050] forKey:AVSampleRateKey];
    [settings setValue: [NSNumber numberWithInt: 1] forKey:AVNumberOfChannelsKey]; // mono
    [settings setValue: [NSNumber numberWithInt:16] forKey:AVLinearPCMBitDepthKey];
    [settings setValue: [NSNumber numberWithBool:NO] forKey:AVLinearPCMIsBigEndianKey];
    //[settings setValue: [NSNumber numberWithInt:16] forKey:AudioSampleType];




    // File URL
    NSURL *url = [NSURL fileURLWithPath:FILEPATH];

    //NSLog(@"Url file path ::: %@",url);

    // Create recorder
    recorder = [[AVAudioRecorder alloc] initWithURL:url settings:settings error:&error];
    if (!recorder)
    {
//        NSLog(@"Error establishing recorder: %@", error.localizedFailureReason);
        return;
    }

Answer 1

感谢上帝和您的支持 friend 。是的，我终于解决了我的问题。不知道方法对不对。但是我的问题已经解决了。我使用上面的代码录制了语音并保存了我的音频。然后我将再次使用以下代码导出音频。我从 https://developer.ibm.com/answers/questions/180732/seems-watson-text-to-speech-service-returns-a-wav.html 得到这段代码

-(NSData*) stripAndAddWavHeader:(NSData*) wav {
    unsigned long wavDataSize = [wav length] - 44;

    NSData *WaveFile= [NSMutableData dataWithData:[wav subdataWithRange:NSMakeRange(44, wavDataSize)]];

    NSMutableData *newWavData;
    newWavData = [self addWavHeader:WaveFile];

    return newWavData;
   }


 - (NSMutableData *)addWavHeader:(NSData *)wavNoheader {

       int headerSize = 44;
       long totalAudioLen = [wavNoheader length];
       long totalDataLen = [wavNoheader length] + headerSize-8;
       long longSampleRate = 22050.0;
       int channels = 1;
       long byteRate = 8 * 44100.0 * channels/8;



     Byte *header = (Byte*)malloc(44);
     header[0] = 'R';  // RIFF/WAVE header
     header[1] = 'I';
     header[2] = 'F';
     header[3] = 'F';
     header[4] = (Byte) (totalDataLen & 0xff);
     header[5] = (Byte) ((totalDataLen >> 8) & 0xff);
     header[6] = (Byte) ((totalDataLen >> 16) & 0xff);
     header[7] = (Byte) ((totalDataLen >> 24) & 0xff);
     header[8] = 'W';
     header[9] = 'A';
     header[10] = 'V';
     header[11] = 'E';
     header[12] = 'f';  // 'fmt ' chunk
     header[13] = 'm';
     header[14] = 't';
     header[15] = ' ';
     header[16] = 16;  // 4 bytes: size of 'fmt ' chunk
     header[17] = 0;
     header[18] = 0;
     header[19] = 0;
     header[20] = 1;  // format = 1
     header[21] = 0;
     header[22] = (Byte) channels;
     header[23] = 0;
     header[24] = (Byte) (longSampleRate & 0xff);
     header[25] = (Byte) ((longSampleRate >> 8) & 0xff);
     header[26] = (Byte) ((longSampleRate >> 16) & 0xff);
     header[27] = (Byte) ((longSampleRate >> 24) & 0xff);
     header[28] = (Byte) (byteRate & 0xff);
     header[29] = (Byte) ((byteRate >> 8) & 0xff);
     header[30] = (Byte) ((byteRate >> 16) & 0xff);
     header[31] = (Byte) ((byteRate >> 24) & 0xff);
     header[32] = (Byte) (2 * 8 / 8);  // block align
     header[33] = 0;
     header[34] = 16;  // bits per sample
     header[35] = 0;
     header[36] = 'd';
     header[37] = 'a';
     header[38] = 't';
     header[39] = 'a';
     header[40] = (Byte) (totalAudioLen & 0xff);
     header[41] = (Byte) ((totalAudioLen >> 8) & 0xff);
     header[42] = (Byte) ((totalAudioLen >> 16) & 0xff);
     header[43] = (Byte) ((totalAudioLen >> 24) & 0xff);

     NSMutableData *newWavData = [NSMutableData dataWithBytes:header length:44];
     [newWavData appendBytes:[wavNoheader bytes] length:[wavNoheader length]];
     return newWavData;
 }