/*
  * VC1 Test Bitstreams Format Demuxer
  * Copyright (c) 2006, 2008 Konstantin Shishkov
  *
  * 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
  */
 
 /**

  * @file

  * VC1 test bitstream file demuxer
  * by Konstantin Shishkov
  * Format specified in SMPTE standard 421 Annex L
  */
 

 #include "libavutil/intreadwrite.h"

 #include "avformat.h"

 #include "internal.h"

 
 #define VC1_EXTRADATA_SIZE 4
 
 static int vc1t_probe(AVProbeData *p)
 {

     if (p->buf_size < 24)
         return 0;
     if (p->buf[3] != 0xC5 || AV_RL32(&p->buf[4]) != 4 || AV_RL32(&p->buf[20]) != 0xC)

         return 0;
 

     return AVPROBE_SCORE_EXTENSION;

 }
 

 static int vc1t_read_header(AVFormatContext *s)

 {

     AVIOContext *pb = s->pb;

     AVStream *st;

     int frames;
     uint32_t fps;

     frames = avio_rl24(pb);
     if(avio_r8(pb) != 0xC5 || avio_rl32(pb) != 4)

         return AVERROR_INVALIDDATA;

 
     /* init video codec */

     st = avformat_new_stream(s, NULL);

     if (!st)

         return AVERROR(ENOMEM);

     st->codecpar->codec_type = AVMEDIA_TYPE_VIDEO;
     st->codecpar->codec_id = AV_CODEC_ID_WMV3;

     if (ff_get_extradata(s, st->codecpar, pb, VC1_EXTRADATA_SIZE) < 0)

         return AVERROR(ENOMEM);

     st->codecpar->height = avio_rl32(pb);
     st->codecpar->width = avio_rl32(pb);

     if(avio_rl32(pb) != 0xC)

         return AVERROR_INVALIDDATA;

     avio_skip(pb, 8);

     fps = avio_rl32(pb);

     if(fps == 0xFFFFFFFF)

         avpriv_set_pts_info(st, 32, 1, 1000);

     else{

         if (!fps) {
             av_log(s, AV_LOG_ERROR, "Zero FPS specified, defaulting to 1 FPS\n");
             fps = 1;
         }

         avpriv_set_pts_info(st, 24, 1, fps);

         st->duration = frames;
     }
 
     return 0;
 }
 
 static int vc1t_read_packet(AVFormatContext *s,
                            AVPacket *pkt)
 {

     AVIOContext *pb = s->pb;

     int frame_size;
     int keyframe = 0;
     uint32_t pts;
 

     if(avio_feof(pb))

         return AVERROR(EIO);
 

     frame_size = avio_rl24(pb);
     if(avio_r8(pb) & 0x80)

         keyframe = 1;

     pts = avio_rl32(pb);

     if(av_get_packet(pb, pkt, frame_size) < 0)
         return AVERROR(EIO);
     if(s->streams[0]->time_base.den == 1000)
         pkt->pts = pts;

     pkt->flags |= keyframe ? AV_PKT_FLAG_KEY : 0;

     pkt->pos -= 8;
 
     return pkt->size;
 }
 

 AVInputFormat ff_vc1t_demuxer = {

     .name           = "vc1test",

     .long_name      = NULL_IF_CONFIG_SMALL("VC-1 test bitstream"),

     .read_probe     = vc1t_probe,
     .read_header    = vc1t_read_header,
     .read_packet    = vc1t_read_packet,

     .flags          = AVFMT_GENERIC_INDEX,

 };