O将音频文件转换为字节数组iPhone时出现错误-40

Question

我在iOS中使用以下代码将mp3文件转换为字节数组。但是，在进入while循环时，它会给出err=-40（OSError=-40）。有人能帮忙吗。或者请告诉我如何将mp3/wav文件转换为字节数组。参考-如何转换WAV/CAF文件'；将样本数据转换为字节数组？

 NSString *urlHere = [[NSBundle mainBundle] pathForResource:@"r2d2" ofType:@"mp3"];
 CFURLRef url = (CFURLRef)[NSURL fileURLWithPath:urlHere];

AudioFileID audioFile;
OSStatus err = AudioFileOpenURL(url, kAudioFileReadPermission, 0, &audioFile);
// get the number of audio data bytes
UInt64 numBytes = 0;
UInt32 dataSize = sizeof(numBytes);
err = AudioFileGetProperty(audioFile, kAudioFilePropertyAudioDataByteCount, &dataSize, &numBytes);
unsigned char *audioBuffer = (unsigned char *)malloc(numBytes);
UInt32 toRead = numBytes;
UInt64 offset = 0;
unsigned char *pBuffer = audioBuffer;
while(true) {
    err = AudioFileReadBytes(audioFile, true, offset, &toRead, &pBuffer);
    if (kAudioFileEndOfFileError == err) {
        // cool, we're at the end of the file
        break;
    } else if (noErr != err) {
        // uh-oh, some error other than eof
        break;
    }
    // advance the next read offset
    offset += toRead;
    // advance the read buffer's pointer
    pBuffer += toRead;
    toRead = numBytes - offset;
    if (0 == toRead) {
        // got to the end of file but no eof err
        break;
    }
}

Answer 1

我遇到了完全相同的问题。您所需要做的就是删除pBuffer变量旁边的&符号，因为它已经是一个指针：

err = AudioFileReadBytes(audioFile, true, offset, &toRead, pBuffer);