fdk-aac将aac格式转为pcm数据

            int sampleRate = 44100; // 采样率int sampleSizeInBits = 16; // 采样位数，通常是16int channels = 2; // 通道数，单声道为1，立体声为2

FILE *m_fd = NULL;FILE *m_fd2 = NULL;HANDLE_AACDECODER decoder = aacDecoder_Open(TT_MP4_ADTS, 1);if (!decoder) {printf("Failed to open AAC decoder");return -1;}m_fd = fopen(s_acc.c_str(), "rb");m_fd2 = fopen(s_pcm.c_str(), "wb");decoder = aacDecoder_Open(TT_MP4_ADTS, 1);if (!decoder) {printf("Failed to open AAC decoder");return -1;}m_fd = fopen(s_acc.c_str(), "rb");m_fd2 = fopen(s_pcm.c_str(), "wb");unsigned int size = 1024;unsigned int valid;unsigned char *data = (unsigned char *) malloc(size);unsigned int decsize = 8 * 2048 * sizeof(INT_PCM);unsigned char *decdata = (unsigned char *) malloc(decsize);int frameCnt = 0;do {int len = fread(data, 1, size, m_fd);if (len <= 0) {break;}valid = len;AAC_DECODER_ERROR err = aacDecoder_Fill(decoder, &data, &size, &valid);//往aac内部缓存中填数据if (err != AAC_DEC_OK) {printf("Failed to fill AAC decoder: %d\n", err);break;}while (1) { //一定要加循环，一次有可能解码不完导致数据丢失err = aacDecoder_DecodeFrame(decoder, (INT_PCM *) decdata, decsize / sizeof(INT_PCM),0);if (err != AAC_DEC_OK) {printf("Failed to DecodeFrame: %d\n", err);break;}//获取解码后码流的信息CStreamInfo *info = aacDecoder_GetStreamInfo(decoder);printf("--------------------frameSize:%d ", info->frameSize);//输出解码数据大小printf("-------------------- sampleRate:%d ", info->sampleRate);//输出解码后采样率printf("-------------------- numChannels:%d ", info->numChannels);//通道数printf("-------------------- aacSampleRate:%d ", info->aacSampleRate);//输入aac数据采样率//int flen = convert_16khz_to_8khz(tmp,decdata,info->frameSize*2); 重采样需要可以到其他链接中获取fwrite(decdata, 1,info->frameSize * 4,  m_fd2);frameCnt++;}} while (1);aacDecoder_Close(decoder);if (data)free(data);if (decdata)free(decdata);if (m_fd)fclose(m_fd);if (m_fd2)fclose(m_fd2);