text: /*
   * VQF demuxer
   * Copyright (c) 2009 Vitor Sessak
   *
   * 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 "avformat.h"
  #include "internal.h"
  #include "libavutil/intreadwrite.h"
  #include "libavutil/dict.h"
  #include "libavutil/mathematics.h"
  #include "riff.h"
  
  typedef struct VqfContext {
      int frame_bit_len;
      uint8_t last_frame_bits;
      int remaining_bits;
  } VqfContext;
  
  static int vqf_probe(const AVProbeData *probe_packet)
  {
      if (AV_RL32(probe_packet->buf) != MKTAG('T','W','I','N'))
          return 0;
  
      if (!memcmp(probe_packet->buf + 4, "97012000", 8))
          return AVPROBE_SCORE_MAX;
  
      if (!memcmp(probe_packet->buf + 4, "00052200", 8))
          return AVPROBE_SCORE_MAX;
  
      if (AV_RL32(probe_packet->buf + 12) > (1<<27))
          return AVPROBE_SCORE_EXTENSION/2;
  
      return AVPROBE_SCORE_EXTENSION;
  }
  
  static void add_metadata(AVFormatContext *s, uint32_t tag,
                           unsigned int tag_len, unsigned int remaining)
  {
      int len = FFMIN(tag_len, remaining);
      char *buf, key[5] = {0};
  
      if (len == UINT_MAX)
          return;
  
      buf = av_malloc(len+1);
      if (!buf)
          return;
      avio_read(s->pb, buf, len);
      buf[len] = 0;
      AV_WL32(key, tag);
      av_dict_set(&s->metadata, key, buf, AV_DICT_DONT_STRDUP_VAL);
  }
  
  static const AVMetadataConv vqf_metadata_conv[] = {
      { "(c) ", "copyright" },
      { "ARNG", "arranger"  },
      { "AUTH", "author"    },
      { "BAND", "band"      },
      { "CDCT", "conductor" },
      { "COMT", "comment"   },
      { "FILE", "filename"  },
      { "GENR", "genre"     },
      { "LABL", "publisher" },
      { "MUSC", "composer"  },
      { "NAME", "title"     },
      { "NOTE", "note"      },
      { "PROD", "producer"  },
      { "PRSN", "personnel" },
      { "REMX", "remixer"   },
      { "SING", "singer"    },
      { "TRCK", "track"     },
      { "WORD", "words"     },
      { 0 },
  };
  
  static int vqf_read_header(AVFormatContext *s)
  {
      VqfContext *c = s->priv_data;
      AVStream *st  = avformat_new_stream(s, NULL);
      int chunk_tag;
      int rate_flag = -1;
      int header_size;
      int read_bitrate = 0;
      int size, ret;
      uint8_t comm_chunk[12];
  
      if (!st)
          return AVERROR(ENOMEM);
  
      avio_skip(s->pb, 12);
  
      header_size = avio_rb32(s->pb);
  
      if (header_size < 0)
          return AVERROR_INVALIDDATA;
  
      st->codecpar->codec_type = AVMEDIA_TYPE_AUDIO;
      st->codecpar->codec_id   = AV_CODEC_ID_TWINVQ;
      st->start_time = 0;
  
      do {
          int len;
          chunk_tag = avio_rl32(s->pb);
  
          if (chunk_tag == MKTAG('D','A','T','A'))
              break;
  
          len = avio_rb32(s->pb);
  
          if ((unsigned) len > INT_MAX/2 || header_size < 8) {
              av_log(s, AV_LOG_ERROR, "Malformed header\n");
              return -1;
          }
  
          header_size -= 8;
  
          switch(chunk_tag){
          case MKTAG('C','O','M','M'):
              if (len < 12)
                  return AVERROR_INVALIDDATA;
  
              avio_read(s->pb, comm_chunk, 12);
              st->codecpar->channels = AV_RB32(comm_chunk    ) + 1;
              read_bitrate        = AV_RB32(comm_chunk + 4);
              rate_flag           = AV_RB32(comm_chunk + 8);
              avio_skip(s->pb, len-12);
  
              if (st->codecpar->channels <= 0) {
                  av_log(s, AV_LOG_ERROR, "Invalid number of channels\n");
                  return AVERROR_INVALIDDATA;
              }
  
              st->codecpar->bit_rate = (int64_t)read_bitrate * 1000;
              break;
          case MKTAG('D','S','I','Z'): // size of compressed data
          {
              av_dict_set_int(&s->metadata, "size", avio_rb32(s->pb), 0);
          }
              break;
          case MKTAG('Y','E','A','R'): // recording date
          case MKTAG('E','N','C','D'): // compression date
          case MKTAG('E','X','T','R'): // reserved
          case MKTAG('_','Y','M','H'): // reserved
          case MKTAG('_','N','T','T'): // reserved
          case MKTAG('_','I','D','3'): // reserved for ID3 tags
              avio_skip(s->pb, FFMIN(len, header_size));
              break;
          default:
              add_metadata(s, chunk_tag, len, header_size);
              break;
          }
  
          header_size -= len;
  
      } while (header_size >= 0 && !avio_feof(s->pb));
  
      switch (rate_flag) {
      case -1:
          av_log(s, AV_LOG_ERROR, "COMM tag not found!\n");
          return -1;
      case 44:
          st->codecpar->sample_rate = 44100;
          break;
      case 22:
          st->codecpar->sample_rate = 22050;
          break;
      case 11:
          st->codecpar->sample_rate = 11025;
          break;
      default:
          if (rate_flag < 8 || rate_flag > 44) {
              av_log(s, AV_LOG_ERROR, "Invalid rate flag %d\n", rate_flag);
              return AVERROR_INVALIDDATA;
          }
          st->codecpar->sample_rate = rate_flag*1000;
          break;
      }
  
      if (read_bitrate / st->codecpar->channels <  8 ||
          read_bitrate / st->codecpar->channels > 48) {
          av_log(s, AV_LOG_ERROR, "Invalid bitrate per channel %d\n",
                 read_bitrate / st->codecpar->channels);
          return AVERROR_INVALIDDATA;
      }
  
      switch (((st->codecpar->sample_rate/1000) << 8) +
              read_bitrate/st->codecpar->channels) {
      case (11<<8) + 8 :
      case (8 <<8) + 8 :
      case (11<<8) + 10:
      case (22<<8) + 32:
          size = 512;
          break;
      case (16<<8) + 16:
      case (22<<8) + 20:
      case (22<<8) + 24:
          size = 1024;
          break;
      case (44<<8) + 40:
      case (44<<8) + 48:
          size = 2048;
          break;
      default:
          av_log(s, AV_LOG_ERROR, "Mode not supported: %d Hz, %"PRId64" kb/s.\n",
                 st->codecpar->sample_rate, st->codecpar->bit_rate);
          return -1;
      }
      c->frame_bit_len = st->codecpar->bit_rate*size/st->codecpar->sample_rate;
      avpriv_set_pts_info(st, 64, size, st->codecpar->sample_rate);
  
      /* put first 12 bytes of COMM chunk in extradata */
      if ((ret = ff_alloc_extradata(st->codecpar, 12)) < 0)
          return ret;
      memcpy(st->codecpar->extradata, comm_chunk, 12);
  
      ff_metadata_conv_ctx(s, NULL, vqf_metadata_conv);
  
      return 0;
  }
  
  static int vqf_read_packet(AVFormatContext *s, AVPacket *pkt)
  {
      VqfContext *c = s->priv_data;
      int ret;
      int size = (c->frame_bit_len - c->remaining_bits + 7)>>3;
  
      if ((ret = av_new_packet(pkt, size + 2)) < 0)
          return ret;
  
      pkt->pos          = avio_tell(s->pb);
      pkt->stream_index = 0;
      pkt->duration     = 1;
  
      pkt->data[0] = 8 - c->remaining_bits; // Number of bits to skip
      pkt->data[1] = c->last_frame_bits;
      ret = avio_read(s->pb, pkt->data+2, size);
  
      if (ret != size) {
          return AVERROR(EIO);
      }
  
      c->last_frame_bits = pkt->data[size+1];
      c->remaining_bits  = (size << 3) - c->frame_bit_len + c->remaining_bits;
  
      return size+2;
  }
  
  static int vqf_read_seek(AVFormatContext *s,
                           int stream_index, int64_t timestamp, int flags)
  {
      VqfContext *c = s->priv_data;
      AVStream *st;
      int64_t ret;
      int64_t pos;
  
      st = s->streams[stream_index];
      pos = av_rescale_rnd(timestamp * st->codecpar->bit_rate,
                           st->time_base.num,
                           st->time_base.den * (int64_t)c->frame_bit_len,
                           (flags & AVSEEK_FLAG_BACKWARD) ?
                                                     AV_ROUND_DOWN : AV_ROUND_UP);
      pos *= c->frame_bit_len;
  
      st->cur_dts = av_rescale(pos, st->time_base.den,
                               st->codecpar->bit_rate * (int64_t)st->time_base.num);
  
      if ((ret = avio_seek(s->pb, ((pos-7) >> 3) + s->internal->data_offset, SEEK_SET)) < 0)
          return ret;
  
      c->remaining_bits = -7 - ((pos-7)&7);
      return 0;
  }
  
  AVInputFormat ff_vqf_demuxer = {
      .name           = "vqf",
      .long_name      = NULL_IF_CONFIG_SMALL("Nippon Telegraph and Telephone Corporation (NTT) TwinVQ"),
      .priv_data_size = sizeof(VqfContext),
      .read_probe     = vqf_probe,
      .read_header    = vqf_read_header,
      .read_packet    = vqf_read_packet,
      .read_seek      = vqf_read_seek,
      .extensions     = "vqf,vql,vqe",
  };
  