AVCodec *codec;
AVCodecContext *avCtx;
AVFrame * decoded_frame = NULL;
uint8_t *outbuf = static_cast<uint8_t *>(malloc(AVCODEC_MAX_AUDIO_FRAME_SIZE));
AVPacket avPacket;

void convBuf(char * input, int numBytes, ofstream& myFile) {

    //copy bytes from buffer
    uint8_t inputBytes[numBytes + FF_INPUT_BUFFER_PADDING_SIZE];
    memset(inputBytes, 0, numBytes + FF_INPUT_BUFFER_PADDING_SIZE);
    memcpy(inputBytes, input, numBytes);
    printf("AVPacket initialisedn");

    avPacket.size = numBytes; //input buffer size
    avPacket.data = inputBytes; // the input buffer
    int len;

    while (avPacket.size > 0) {

    int got_frame = 0;
    if (!decoded_frame) {

        if (!(decoded_frame = avcodec_alloc_frame())) {
            printf("out of memory");
            return;
        }
    } else {
        avcodec_get_frame_defaults(decoded_frame);
    }

    //-------------------->> returns always -22
    len = avcodec_decode_audio4(avCtx, decoded_frame, &got_frame, &avPacket);

    if (len < 0) {
        printf("Error while decoding:%d",len);
        return;
    }

        if (got_frame) {
            //do something with the decoded frame
    }
        avPacket.size -= len;
        avPacket.data += len;
    }

    return;
}



main(){
    av_register_all();

    codec = avcodec_find_decoder(CODEC_ID_AAC);

    if (codec == NULL) {
        printf("Cant find AAC codecn");
        return 0;
    }
    printf("AAC codec foundn");

    //set parameters
    avCtx = avcodec_alloc_context3(codec);
    avCtx->channels = 1;
    avCtx->sample_rate = 44100;
    avCtx->bit_rate=16;

    avCtx->sample_fmt = AV_SAMPLE_FMT_S16;

    if (avCtx == NULL) {
        printf("Could not allocate codec contextn");
        return 0;
    }
    printf("codec context allocatedn");

    if (avcodec_open2(avCtx, codec, NULL) < 0) {
        printf("Could not open codecn");
        return 0;
    }
    printf("AAC codec opened");
    av_init_packet(&avPacket);
    ifstream file("audio_adts.m4a", ios :: binary);

    //Main reader loop
    while(1) {
        memset(buf ,0 , 4096);
        file.read(buf,framesize);
        convBuf(buf,framesize,myFile);
    }
    myFile.close();

    printf("Freeing memoryn");
    av_free_packet(&avPacket);
    avcodec_close(avCtx);
    return 0;
}