static int aac_decode_frame_int(AVCodecContext *avctx, void *data,
                                int *got_frame_ptr, GetBitContext *gb, AVPacket *avpkt)
{
    AACContext *ac = avctx->priv_data;
    ChannelElement *che = NULL, *che_prev = NULL;
    enum RawDataBlockType elem_type, elem_type_prev = TYPE_END;
    int err, elem_id;
    int samples = 0, multiplier, audio_found = 0, pce_found = 0;
    int is_dmono, sce_count = 0;

    ac->frame = data;

    if (show_bits(gb, 12) == 0xfff) {
        if ((err = parse_adts_frame_header(ac, gb)) < 0) {
            av_log(avctx, AV_LOG_ERROR, "Error decoding AAC frame header.\n");
            goto fail;
        }
        if (ac->oc[1].m4ac.sampling_index > 12) {
            av_log(ac->avctx, AV_LOG_ERROR, "invalid sampling rate index %d\n", ac->oc[1].m4ac.sampling_index);
            err = AVERROR_INVALIDDATA;
            goto fail;
        }
    }

    if ((err = frame_configure_elements(avctx)) < 0)
        goto fail;

    // The FF_PROFILE_AAC_* defines are all object_type - 1
    // This may lead to an undefined profile being signaled
    ac->avctx->profile = ac->oc[1].m4ac.object_type - 1;

    ac->tags_mapped = 0;
    // parse
    while ((elem_type = get_bits(gb, 3)) != TYPE_END) {
        elem_id = get_bits(gb, 4);

        if (elem_type < TYPE_DSE) {
            if (!(che=get_che(ac, elem_type, elem_id))) {
                av_log(ac->avctx, AV_LOG_ERROR, "channel element %d.%d is not allocated\n",
                       elem_type, elem_id);
                err = AVERROR_INVALIDDATA;
                goto fail;
            }
            samples = 1024;
        }

        switch (elem_type) {

        case TYPE_SCE:
            err = decode_ics(ac, &che->ch[0], gb, 0, 0);
            audio_found = 1;
            sce_count++;
            break;

        case TYPE_CPE:
            err = decode_cpe(ac, gb, che);
            audio_found = 1;
            break;

        case TYPE_CCE:
            err = decode_cce(ac, gb, che);
            break;

        case TYPE_LFE:
            err = decode_ics(ac, &che->ch[0], gb, 0, 0);
            audio_found = 1;
            break;

        case TYPE_DSE:
            err = skip_data_stream_element(ac, gb);
            break;

        case TYPE_PCE: {
            uint8_t layout_map[MAX_ELEM_ID*4][3];
            int tags;
            push_output_configuration(ac);
            tags = decode_pce(avctx, &ac->oc[1].m4ac, layout_map, gb);
            if (tags < 0) {
                err = tags;
                break;
            }
            if (pce_found) {
                av_log(avctx, AV_LOG_ERROR,
                       "Not evaluating a further program_config_element as this construct is dubious at best.\n");
            } else {
                err = output_configure(ac, layout_map, tags, OC_TRIAL_PCE, 1);
                if (!err)
                    ac->oc[1].m4ac.chan_config = 0;
                pce_found = 1;
            }
            break;
        }

        case TYPE_FIL:
            if (elem_id == 15)
                elem_id += get_bits(gb, 8) - 1;
            if (get_bits_left(gb) < 8 * elem_id) {
                    av_log(avctx, AV_LOG_ERROR, "TYPE_FIL: "overread_err);
                    err = AVERROR_INVALIDDATA;
                    goto fail;
            }
            while (elem_id > 0)
                elem_id -= decode_extension_payload(ac, gb, elem_id, che_prev, elem_type_prev);
            err = 0; /* FIXME */
            break;

        default:
            err = AVERROR_BUG; /* should not happen, but keeps compiler happy */
            break;
        }

        che_prev       = che;
        elem_type_prev = elem_type;

        if (err)
            goto fail;

        if (get_bits_left(gb) < 3) {
            av_log(avctx, AV_LOG_ERROR, overread_err);
            err = AVERROR_INVALIDDATA;
            goto fail;
        }
    }

    spectral_to_sample(ac);

    multiplier = (ac->oc[1].m4ac.sbr == 1) ? ac->oc[1].m4ac.ext_sample_rate > ac->oc[1].m4ac.sample_rate : 0;
    samples <<= multiplier;
    /* for dual-mono audio (SCE + SCE) */
    is_dmono = ac->dmono_mode && sce_count == 2 &&
               ac->oc[1].channel_layout == (AV_CH_FRONT_LEFT | AV_CH_FRONT_RIGHT);

    if (samples)
        ac->frame->nb_samples = samples;
    else
        av_frame_unref(ac->frame);
    *got_frame_ptr = !!samples;

    if (is_dmono) {
        if (ac->dmono_mode == 1)
            ((AVFrame *)data)->data[1] =((AVFrame *)data)->data[0];
        else if (ac->dmono_mode == 2)
            ((AVFrame *)data)->data[0] =((AVFrame *)data)->data[1];
    }

    if (ac->oc[1].status && audio_found) {
        avctx->sample_rate = ac->oc[1].m4ac.sample_rate << multiplier;
        avctx->frame_size = samples;
        ac->oc[1].status = OC_LOCKED;
    }

    if (multiplier) {
        int side_size;
        const uint8_t *side = av_packet_get_side_data(avpkt, AV_PKT_DATA_SKIP_SAMPLES, &side_size);
        if (side && side_size>=4)
            AV_WL32(side, 2*AV_RL32(side));
    }
    return 0;
fail:
    pop_output_configuration(ac);
    return err;
}
Unknown