static int h264_decode_frame(AVCodecContext *avctx, void *data,
                             int *got_frame, AVPacket *avpkt)
{
    const uint8_t *buf = avpkt->data;
    int buf_size       = avpkt->size;
    H264Context *h     = avctx->priv_data;
    AVFrame *pict      = data;
    int buf_index      = 0;
    H264Picture *out;
    int i, out_idx;
    int ret;
    h->flags = avctx->flags;
    ff_h264_unref_picture(h, &h->last_pic_for_ec);
    /* end of stream, output what is still in the buffers */
    if (buf_size == 0) {
 out:
        h->cur_pic_ptr = NULL;
        h->first_field = 0;
        // FIXME factorize this with the output code below
        out     = h->delayed_pic[0];
        out_idx = 0;
        for (i = 1;
             h->delayed_pic[i] &&
             !h->delayed_pic[i]->f->key_frame &&
             !h->delayed_pic[i]->mmco_reset;
             i++)
            if (h->delayed_pic[i]->poc < out->poc) {
                out     = h->delayed_pic[i];
                out_idx = i;
        for (i = out_idx; h->delayed_pic[i]; i++)
            h->delayed_pic[i] = h->delayed_pic[i + 1];
        if (out) {
            out->reference &= ~DELAYED_PIC_REF;
            ret = output_frame(h, pict, out);
            if (ret < 0)
                return ret;
            *got_frame = 1;
        return buf_index;
    if (h->is_avc && av_packet_get_side_data(avpkt, AV_PKT_DATA_NEW_EXTRADATA, NULL)) {
        int side_size;
        uint8_t *side = av_packet_get_side_data(avpkt, AV_PKT_DATA_NEW_EXTRADATA, &side_size);
        if (is_extra(side, side_size))
            ff_h264_decode_extradata(h, side, side_size);
    if(h->is_avc && buf_size >= 9 && buf[0]==1 && buf[2]==0 && (buf[4]&0xFC)==0xFC && (buf[5]&0x1F) && buf[8]==0x67){
        if (is_extra(buf, buf_size))
            return ff_h264_decode_extradata(h, buf, buf_size);
    buf_index = decode_nal_units(h, buf, buf_size, 0);
    if (buf_index < 0)
        return AVERROR_INVALIDDATA;
    if (!h->cur_pic_ptr && h->nal_unit_type == NAL_END_SEQUENCE) {
        av_assert0(buf_index <= buf_size);
        goto out;
    if (!(avctx->flags2 & CODEC_FLAG2_CHUNKS) && !h->cur_pic_ptr) {
        if (avctx->skip_frame >= AVDISCARD_NONREF ||
            buf_size >= 4 && !memcmp("Q264", buf, 4))
            return buf_size;
        av_log(avctx, AV_LOG_ERROR, "no frame!\n");
        return AVERROR_INVALIDDATA;
    if (!(avctx->flags2 & CODEC_FLAG2_CHUNKS) ||
        (h->mb_y >= h->mb_height && h->mb_height)) {
        if (avctx->flags2 & CODEC_FLAG2_CHUNKS)
            decode_postinit(h, 1);
        ff_h264_field_end(h, &h->slice_ctx[0], 0);
        /* Wait for second field. */
        *got_frame = 0;
        if (h->next_output_pic && (
                                   h->next_output_pic->recovered)) {
            if (!h->next_output_pic->recovered)
                h->next_output_pic->f->flags |= AV_FRAME_FLAG_CORRUPT;
            if (!h->avctx->hwaccel &&
                 (h->next_output_pic->field_poc[0] == INT_MAX ||
                  h->next_output_pic->field_poc[1] == INT_MAX)
            ) {
                int p;
                AVFrame *f = h->next_output_pic->f;
                int field = h->next_output_pic->field_poc[0] == INT_MAX;
                uint8_t *dst_data[4];
                int linesizes[4];
                const uint8_t *src_data[4];
                av_log(h->avctx, AV_LOG_DEBUG, "Duplicating field %d to fill missing\n", field);
                for (p = 0; p<4; p++) {
                    dst_data[p] = f->data[p] + (field^1)*f->linesize[p];
                    src_data[p] = f->data[p] +  field   *f->linesize[p];
                    linesizes[p] = 2*f->linesize[p];
                av_image_copy(dst_data, linesizes, src_data, linesizes,
                              f->format, f->width, f->height>>1);
            ret = output_frame(h, pict, h->next_output_pic);
            if (ret < 0)
                return ret;
            *got_frame = 1;
            if (CONFIG_MPEGVIDEO) {
                ff_print_debug_info2(h->avctx, pict, NULL,
                                    h->next_output_pic->mb_type,
                                    h->next_output_pic->qscale_table,
                                    h->next_output_pic->motion_val,
                                    &h->low_delay,
                                    h->mb_width, h->mb_height, h->mb_stride, 1);
    av_assert0(pict->buf[0] || !*got_frame);
    ff_h264_unref_picture(h, &h->last_pic_for_ec);
    return get_consumed_bytes(buf_index, buf_size);