Function decode_frame

libavcodec/dstdec.c:242–384

}

static int decode_frame(AVCodecContext *avctx, AVFrame *frame,
                        int *got_frame_ptr, AVPacket *avpkt)
{
    unsigned samples_per_frame = DST_SAMPLES_PER_FRAME(avctx->sample_rate);
    unsigned map_ch_to_felem[DST_MAX_CHANNELS];
    unsigned map_ch_to_pelem[DST_MAX_CHANNELS];
    unsigned i, ch, same_map, dst_x_bit;
    unsigned half_prob[DST_MAX_CHANNELS];
    const int channels = avctx->ch_layout.nb_channels;
    DSTContext *s = avctx->priv_data;
    GetBitContext *gb = &s->gb;
    ArithCoder *ac = &s->ac;
    uint8_t *dsd;
    float *pcm;
    int ret;

    if (avpkt->size <= 1)
        return AVERROR_INVALIDDATA;

    frame->nb_samples = samples_per_frame / 8;
    if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
        return ret;
    dsd = frame->data[0];
    pcm = (float *)frame->data[0];

    if ((ret = init_get_bits8(gb, avpkt->data, avpkt->size)) < 0)
        return ret;

    if (!get_bits1(gb)) {
        skip_bits1(gb);
        if (get_bits(gb, 6))
            return AVERROR_INVALIDDATA;
        memcpy(frame->data[0], avpkt->data + 1, FFMIN(avpkt->size - 1, frame->nb_samples * channels));
        goto dsd;
    }

    /* Segmentation (10.4, 10.5, 10.6) */

    if (!get_bits1(gb)) {
        avpriv_request_sample(avctx, "Not Same Segmentation");
        return AVERROR_PATCHWELCOME;
    }

    if (!get_bits1(gb)) {
        avpriv_request_sample(avctx, "Not Same Segmentation For All Channels");
        return AVERROR_PATCHWELCOME;
    }

    if (!get_bits1(gb)) {
        avpriv_request_sample(avctx, "Not End Of Channel Segmentation");
        return AVERROR_PATCHWELCOME;
    }

    /* Mapping (10.7, 10.8, 10.9) */

    same_map = get_bits1(gb);

    if ((ret = read_map(gb, &s->fsets, map_ch_to_felem, channels)) < 0)