int ff_h264_decode_seq_parameter_set(H264Context *h){

    MpegEncContext * const s = &h->s;

    int profile_idc, level_idc, constraint_set_flags = 0;

    unsigned int sps_id;

    int i, log2_max_frame_num_minus4;

    SPS *sps;



    profile_idc= get_bits(&s->gb, 8);

    constraint_set_flags |= get_bits1(&s->gb) << 0;   

    constraint_set_flags |= get_bits1(&s->gb) << 1;   

    constraint_set_flags |= get_bits1(&s->gb) << 2;   

    constraint_set_flags |= get_bits1(&s->gb) << 3;   

    get_bits(&s->gb, 4); 

    level_idc= get_bits(&s->gb, 8);

    sps_id= get_ue_golomb_31(&s->gb);



    if(sps_id >= MAX_SPS_COUNT) {

        av_log(h->s.avctx, AV_LOG_ERROR, "sps_id (%d) out of range\n", sps_id);

        return -1;

    }

    sps= av_mallocz(sizeof(SPS));

    if(sps == NULL)

        return -1;



    sps->time_offset_length = 24;

    sps->profile_idc= profile_idc;

    sps->constraint_set_flags = constraint_set_flags;

    sps->level_idc= level_idc;



    memset(sps->scaling_matrix4, 16, sizeof(sps->scaling_matrix4));

    memset(sps->scaling_matrix8, 16, sizeof(sps->scaling_matrix8));

    sps->scaling_matrix_present = 0;



    if(sps->profile_idc >= 100){ 

        sps->chroma_format_idc= get_ue_golomb_31(&s->gb);

        if(sps->chroma_format_idc > 3) {

            av_log(h->s.avctx, AV_LOG_ERROR, "chroma_format_idc (%u) out of range\n", sps->chroma_format_idc);

            goto fail;

        } else if(sps->chroma_format_idc == 3) {

            sps->residual_color_transform_flag = get_bits1(&s->gb);

        }

        sps->bit_depth_luma   = get_ue_golomb(&s->gb) + 8;

        sps->bit_depth_chroma = get_ue_golomb(&s->gb) + 8;

        sps->transform_bypass = get_bits1(&s->gb);

        decode_scaling_matrices(h, sps, NULL, 1, sps->scaling_matrix4, sps->scaling_matrix8);

    }else{

        sps->chroma_format_idc= 1;

        sps->bit_depth_luma   = 8;

        sps->bit_depth_chroma = 8;

    }



    log2_max_frame_num_minus4 = get_ue_golomb(&s->gb);

    if (log2_max_frame_num_minus4 < MIN_LOG2_MAX_FRAME_NUM - 4 ||

        log2_max_frame_num_minus4 > MAX_LOG2_MAX_FRAME_NUM - 4) {

        av_log(h->s.avctx, AV_LOG_ERROR,

               "log2_max_frame_num_minus4 out of range (0-12): %d\n",

               log2_max_frame_num_minus4);

        return AVERROR_INVALIDDATA;

    }

    sps->log2_max_frame_num = log2_max_frame_num_minus4 + 4;



    sps->poc_type= get_ue_golomb_31(&s->gb);



    if(sps->poc_type == 0){ 

        sps->log2_max_poc_lsb= get_ue_golomb(&s->gb) + 4;

    } else if(sps->poc_type == 1){

        sps->delta_pic_order_always_zero_flag= get_bits1(&s->gb);

        sps->offset_for_non_ref_pic= get_se_golomb(&s->gb);

        sps->offset_for_top_to_bottom_field= get_se_golomb(&s->gb);

        sps->poc_cycle_length                = get_ue_golomb(&s->gb);



        if((unsigned)sps->poc_cycle_length >= FF_ARRAY_ELEMS(sps->offset_for_ref_frame)){

            av_log(h->s.avctx, AV_LOG_ERROR, "poc_cycle_length overflow %u\n", sps->poc_cycle_length);

            goto fail;

        }



        for(i=0; i<sps->poc_cycle_length; i++)

            sps->offset_for_ref_frame[i]= get_se_golomb(&s->gb);

    }else if(sps->poc_type != 2){

        av_log(h->s.avctx, AV_LOG_ERROR, "illegal POC type %d\n", sps->poc_type);

        goto fail;

    }



    sps->ref_frame_count= get_ue_golomb_31(&s->gb);

    if(sps->ref_frame_count > MAX_PICTURE_COUNT-2 || sps->ref_frame_count >= 32U){

        av_log(h->s.avctx, AV_LOG_ERROR, "too many reference frames\n");

        goto fail;

    }

    sps->gaps_in_frame_num_allowed_flag= get_bits1(&s->gb);

    sps->mb_width = get_ue_golomb(&s->gb) + 1;

    sps->mb_height= get_ue_golomb(&s->gb) + 1;

    if((unsigned)sps->mb_width >= INT_MAX/16 || (unsigned)sps->mb_height >= INT_MAX/16 ||

       av_image_check_size(16*sps->mb_width, 16*sps->mb_height, 0, h->s.avctx)){

        av_log(h->s.avctx, AV_LOG_ERROR, "mb_width/height overflow\n");

        goto fail;

    }



    sps->frame_mbs_only_flag= get_bits1(&s->gb);

    if(!sps->frame_mbs_only_flag)

        sps->mb_aff= get_bits1(&s->gb);

    else

        sps->mb_aff= 0;



    sps->direct_8x8_inference_flag= get_bits1(&s->gb);

    if(!sps->frame_mbs_only_flag && !sps->direct_8x8_inference_flag){

        av_log(h->s.avctx, AV_LOG_ERROR, "This stream was generated by a broken encoder, invalid 8x8 inference\n");

        goto fail;

    }



#ifndef ALLOW_INTERLACE

    if(sps->mb_aff)

        av_log(h->s.avctx, AV_LOG_ERROR, "MBAFF support not included; enable it at compile-time.\n");

#endif

    sps->crop= get_bits1(&s->gb);

    if(sps->crop){

        int crop_vertical_limit   = sps->chroma_format_idc  & 2 ? 16 : 8;

        int crop_horizontal_limit = sps->chroma_format_idc == 3 ? 16 : 8;

        sps->crop_left  = get_ue_golomb(&s->gb);

        sps->crop_right = get_ue_golomb(&s->gb);

        sps->crop_top   = get_ue_golomb(&s->gb);

        sps->crop_bottom= get_ue_golomb(&s->gb);

        if(sps->crop_left || sps->crop_top){

            av_log(h->s.avctx, AV_LOG_ERROR, "insane cropping not completely supported, this could look slightly wrong ...\n");

        }

        if(sps->crop_right >= crop_horizontal_limit || sps->crop_bottom >= crop_vertical_limit){

            av_log(h->s.avctx, AV_LOG_ERROR, "brainfart cropping not supported, this could look slightly wrong ...\n");

        }

    }else{

        sps->crop_left  =

        sps->crop_right =

        sps->crop_top   =

        sps->crop_bottom= 0;

    }



    sps->vui_parameters_present_flag= get_bits1(&s->gb);

    if( sps->vui_parameters_present_flag )

        if (decode_vui_parameters(h, sps) < 0)

            goto fail;



    if(!sps->sar.den)

        sps->sar.den= 1;



    if(s->avctx->debug&FF_DEBUG_PICT_INFO){

        static const char csp[4][5] = { "Gray", "420", "422", "444" };

        av_log(h->s.avctx, AV_LOG_DEBUG, "sps:%u profile:%d/%d poc:%d ref:%d %dx%d %s %s crop:%d/%d/%d/%d %s %s %d/%d\n",

               sps_id, sps->profile_idc, sps->level_idc,

               sps->poc_type,

               sps->ref_frame_count,

               sps->mb_width, sps->mb_height,

               sps->frame_mbs_only_flag ? "FRM" : (sps->mb_aff ? "MB-AFF" : "PIC-AFF"),

               sps->direct_8x8_inference_flag ? "8B8" : "",

               sps->crop_left, sps->crop_right,

               sps->crop_top, sps->crop_bottom,

               sps->vui_parameters_present_flag ? "VUI" : "",

               csp[sps->chroma_format_idc],

               sps->timing_info_present_flag ? sps->num_units_in_tick : 0,

               sps->timing_info_present_flag ? sps->time_scale : 0

               );

    }



    av_free(h->sps_buffers[sps_id]);

    h->sps_buffers[sps_id]= sps;

    h->sps = *sps;

    return 0;

fail:

    av_free(sps);

    return -1;

}
