/*
  * RAW dvbsub demuxer
  * Copyright (c) 2015 Michael Niedermayer <michaelni@gmx.at>
  *
  * This file is part of FFmpeg.
  *
  * FFmpeg is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
  * License as published by the Free Software Foundation; either
  * version 2.1 of the License, or (at your option) any later version.
  *
  * FFmpeg is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
  * License along with FFmpeg; if not, write to the Free Software
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  */
 
 #include "libavutil/intreadwrite.h"
 
 #include "avformat.h"
 #include "rawdec.h"
 
 
 static int dvbsub_probe(AVProbeData *p)
 {
     int i, j, k;
     const uint8_t *end = p->buf + p->buf_size;

     int type, len;

     int max_score = 0;
 
     for(i=0; i<p->buf_size; i++){

         if (p->buf[i] == 0x0f) {

             const uint8_t *ptr = p->buf + i;
             uint8_t histogram[6] = {0};
             int min = 255;

             for(j=0; 6 < end - ptr; j++) {

                 if (*ptr != 0x0f)
                     break;
                 type    = ptr[1];

                 //page_id = AV_RB16(ptr + 2);

                 len     = AV_RB16(ptr + 4);
                 if (type == 0x80) {
                     ;
                 } else if (type >= 0x10 && type <= 0x14) {
                     histogram[type - 0x10] ++;
                 } else
                     break;

                 if (6 + len > end - ptr)
                     break;

                 ptr += 6 + len;
             }
             for (k=0; k < 4; k++) {
                 min = FFMIN(min, histogram[k]);
             }
             if (min && j > max_score)
                 max_score = j;

         }

     }
 
     if (max_score > 5)

         return AVPROBE_SCORE_EXTENSION;

 
     return 0;
 }
 
 FF_DEF_RAWSUB_DEMUXER(dvbsub, "raw dvbsub", dvbsub_probe, NULL, AV_CODEC_ID_DVB_SUBTITLE, AVFMT_GENERIC_INDEX)