text: /*
   * AIFF/AIFF-C demuxer
   * Copyright (c) 2006  Patrick Guimond
   *
   * 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 "libavutil/mathematics.h"
  #include "libavutil/dict.h"
  #include "avformat.h"
  #include "internal.h"
  #include "pcm.h"
  #include "aiff.h"
  #include "isom.h"
  #include "id3v2.h"
  #include "mov_chan.h"
  
  #define AIFF                    0
  #define AIFF_C_VERSION1         0xA2805140
  
  typedef struct AIFFInputContext {
      int64_t data_end;
      int block_duration;
  } AIFFInputContext;
  
  static enum AVCodecID aiff_codec_get_id(int bps)
  {
      if (bps <= 8)
          return AV_CODEC_ID_PCM_S8;
      if (bps <= 16)
          return AV_CODEC_ID_PCM_S16BE;
      if (bps <= 24)
          return AV_CODEC_ID_PCM_S24BE;
      if (bps <= 32)
          return AV_CODEC_ID_PCM_S32BE;
  
      /* bigger than 32 isn't allowed  */
      return AV_CODEC_ID_NONE;
  }
  
  /* returns the size of the found tag */
  static int get_tag(AVIOContext *pb, uint32_t * tag)
  {
      int size;
  
      if (avio_feof(pb))
          return AVERROR(EIO);
  
      *tag = avio_rl32(pb);
      size = avio_rb32(pb);
  
      if (size < 0)
          size = 0x7fffffff;
  
      return size;
  }
  
  /* Metadata string read */
  static void get_meta(AVFormatContext *s, const char *key, int size)
  {
      uint8_t *str = av_malloc(size+1);
  
      if (str) {
          int res = avio_read(s->pb, str, size);
          if (res < 0){
              av_free(str);
              return;
          }
          size += (size&1)-res;
          str[res] = 0;
          av_dict_set(&s->metadata, key, str, AV_DICT_DONT_STRDUP_VAL);
      }else
          size+= size&1;
  
      avio_skip(s->pb, size);
  }
  
  /* Returns the number of sound data frames or negative on error */
  static int get_aiff_header(AVFormatContext *s, int size,
                                      unsigned version)
  {
      AVIOContext *pb        = s->pb;
      AVCodecParameters *par = s->streams[0]->codecpar;
      AIFFInputContext *aiff = s->priv_data;
      int exp;
      uint64_t val;
      int sample_rate;
      unsigned int num_frames;
  
      if (size & 1)
          size++;
      par->codec_type = AVMEDIA_TYPE_AUDIO;
      par->channels = avio_rb16(pb);
      num_frames = avio_rb32(pb);
      par->bits_per_coded_sample = avio_rb16(pb);
  
      exp = avio_rb16(pb) - 16383 - 63;
      val = avio_rb64(pb);
      if (exp <-63 || exp >63) {
          av_log(s, AV_LOG_ERROR, "exp %d is out of range\n", exp);
          return AVERROR_INVALIDDATA;
      }
      if (exp >= 0)
          sample_rate = val << exp;
      else
          sample_rate = (val + (1ULL<<(-exp-1))) >> -exp;
      par->sample_rate = sample_rate;
      size -= 18;
  
      /* get codec id for AIFF-C */
      if (size < 4) {
          version = AIFF;
      } else if (version == AIFF_C_VERSION1) {
          par->codec_tag = avio_rl32(pb);
          par->codec_id  = ff_codec_get_id(ff_codec_aiff_tags, par->codec_tag);
          if (par->codec_id == AV_CODEC_ID_NONE) {
              char tag[32];
              av_get_codec_tag_string(tag, sizeof(tag), par->codec_tag);
              avpriv_request_sample(s, "unknown or unsupported codec tag: %s", tag);
          }
          size -= 4;
      }
  
      if (version != AIFF_C_VERSION1 || par->codec_id == AV_CODEC_ID_PCM_S16BE) {
          par->codec_id = aiff_codec_get_id(par->bits_per_coded_sample);
          par->bits_per_coded_sample = av_get_bits_per_sample(par->codec_id);
          aiff->block_duration = 1;
      } else {
          switch (par->codec_id) {
          case AV_CODEC_ID_PCM_F32BE:
          case AV_CODEC_ID_PCM_F64BE:
          case AV_CODEC_ID_PCM_S16LE:
          case AV_CODEC_ID_PCM_ALAW:
          case AV_CODEC_ID_PCM_MULAW:
              aiff->block_duration = 1;
              break;
          case AV_CODEC_ID_ADPCM_IMA_QT:
              par->block_align = 34 * par->channels;
              break;
          case AV_CODEC_ID_MACE3:
              par->block_align = 2 * par->channels;
              break;
          case AV_CODEC_ID_ADPCM_G726LE:
              par->bits_per_coded_sample = 5;
          case AV_CODEC_ID_ADPCM_IMA_WS:
          case AV_CODEC_ID_ADPCM_G722:
          case AV_CODEC_ID_MACE6:
          case AV_CODEC_ID_SDX2_DPCM:
              par->block_align = 1 * par->channels;
              break;
          case AV_CODEC_ID_GSM:
              par->block_align = 33;
              break;
          default:
              aiff->block_duration = 1;
              break;
          }
          if (par->block_align > 0)
              aiff->block_duration = av_get_audio_frame_duration2(par,
                                                                  par->block_align);
      }
  
      /* Block align needs to be computed in all cases, as the definition
       * is specific to applications -> here we use the WAVE format definition */
      if (!par->block_align)
          par->block_align = (av_get_bits_per_sample(par->codec_id) * par->channels) >> 3;
  
      if (aiff->block_duration) {
          par->bit_rate = par->sample_rate * (par->block_align << 3) /
                          aiff->block_duration;
      }
  
      /* Chunk is over */
      if (size)
          avio_skip(pb, size);
  
      return num_frames;
  }
  
  static int aiff_probe(AVProbeData *p)
  {
      /* check file header */
      if (p->buf[0] == 'F' && p->buf[1] == 'O' &&
          p->buf[2] == 'R' && p->buf[3] == 'M' &&
          p->buf[8] == 'A' && p->buf[9] == 'I' &&
          p->buf[10] == 'F' && (p->buf[11] == 'F' || p->buf[11] == 'C'))
          return AVPROBE_SCORE_MAX;
      else
          return 0;
  }
  
  /* aiff input */
  static int aiff_read_header(AVFormatContext *s)
  {
      int ret, size, filesize;
      int64_t offset = 0, position;
      uint32_t tag;
      unsigned version = AIFF_C_VERSION1;
      AVIOContext *pb = s->pb;
      AVStream * st;
      AIFFInputContext *aiff = s->priv_data;
      ID3v2ExtraMeta *id3v2_extra_meta = NULL;
  
      /* check FORM header */
      filesize = get_tag(pb, &tag);
      if (filesize < 0 || tag != MKTAG('F', 'O', 'R', 'M'))
          return AVERROR_INVALIDDATA;
  
      /* AIFF data type */
      tag = avio_rl32(pb);
      if (tag == MKTAG('A', 'I', 'F', 'F'))       /* Got an AIFF file */
          version = AIFF;
      else if (tag != MKTAG('A', 'I', 'F', 'C'))  /* An AIFF-C file then */
          return AVERROR_INVALIDDATA;
  
      filesize -= 4;
  
      st = avformat_new_stream(s, NULL);
      if (!st)
          return AVERROR(ENOMEM);
  
      while (filesize > 0) {
          /* parse different chunks */
          size = get_tag(pb, &tag);
  
          if (size == AVERROR_EOF && offset > 0 && st->codecpar->block_align) {
              av_log(s, AV_LOG_WARNING, "header parser hit EOF\n");
              goto got_sound;
          }
          if (size < 0)
              return size;
  
          filesize -= size + 8;
  
          switch (tag) {
          case MKTAG('C', 'O', 'M', 'M'):     /* Common chunk */
              /* Then for the complete header info */
              st->nb_frames = get_aiff_header(s, size, version);
              if (st->nb_frames < 0)
                  return st->nb_frames;
              if (offset > 0) // COMM is after SSND
                  goto got_sound;
              break;
          case MKTAG('I', 'D', '3', ' '):
              position = avio_tell(pb);
              ff_id3v2_read(s, ID3v2_DEFAULT_MAGIC, &id3v2_extra_meta, size);
              if (id3v2_extra_meta)
                  if ((ret = ff_id3v2_parse_apic(s, &id3v2_extra_meta)) < 0) {
                      ff_id3v2_free_extra_meta(&id3v2_extra_meta);
                      return ret;
                  }
              ff_id3v2_free_extra_meta(&id3v2_extra_meta);
              if (position + size > avio_tell(pb))
                  avio_skip(pb, position + size - avio_tell(pb));
              break;
          case MKTAG('F', 'V', 'E', 'R'):     /* Version chunk */
              version = avio_rb32(pb);
              break;
          case MKTAG('N', 'A', 'M', 'E'):     /* Sample name chunk */
              get_meta(s, "title"    , size);
              break;
          case MKTAG('A', 'U', 'T', 'H'):     /* Author chunk */
              get_meta(s, "author"   , size);
              break;
          case MKTAG('(', 'c', ')', ' '):     /* Copyright chunk */
              get_meta(s, "copyright", size);
              break;
          case MKTAG('A', 'N', 'N', 'O'):     /* Annotation chunk */
              get_meta(s, "comment"  , size);
              break;
          case MKTAG('S', 'S', 'N', 'D'):     /* Sampled sound chunk */
              aiff->data_end = avio_tell(pb) + size;
              offset = avio_rb32(pb);      /* Offset of sound data */
              avio_rb32(pb);               /* BlockSize... don't care */
              offset += avio_tell(pb);    /* Compute absolute data offset */
              if (st->codecpar->block_align && !pb->seekable)    /* Assume COMM already parsed */
                  goto got_sound;
              if (!pb->seekable) {
                  av_log(s, AV_LOG_ERROR, "file is not seekable\n");
                  return -1;
              }
              avio_skip(pb, size - 8);
              break;
          case MKTAG('w', 'a', 'v', 'e'):
              if ((uint64_t)size > (1<<30))
                  return -1;
              if (ff_get_extradata(s, st->codecpar, pb, size) < 0)
                  return AVERROR(ENOMEM);
              if (st->codecpar->codec_id == AV_CODEC_ID_QDM2 && size>=12*4 && !st->codecpar->block_align) {
                  st->codecpar->block_align = AV_RB32(st->codecpar->extradata+11*4);
                  aiff->block_duration = AV_RB32(st->codecpar->extradata+9*4);
              } else if (st->codecpar->codec_id == AV_CODEC_ID_QCELP) {
                  char rate = 0;
                  if (size >= 25)
                      rate = st->codecpar->extradata[24];
                  switch (rate) {
                  case 'H': // RATE_HALF
                      st->codecpar->block_align = 17;
                      break;
                  case 'F': // RATE_FULL
                  default:
                      st->codecpar->block_align = 35;
                  }
                  aiff->block_duration = 160;
                  st->codecpar->bit_rate = st->codecpar->sample_rate * (st->codecpar->block_align << 3) /
                                           aiff->block_duration;
              }
              break;
          case MKTAG('C','H','A','N'):
              if(ff_mov_read_chan(s, pb, st, size) < 0)
                  return AVERROR_INVALIDDATA;
              break;
          case 0:
              if (offset > 0 && st->codecpar->block_align) // COMM && SSND
                  goto got_sound;
          default: /* Jump */
              if (size & 1)   /* Always even aligned */
                  size++;
              avio_skip(pb, size);
          }
      }
  
  got_sound:
      if (!st->codecpar->block_align) {
          av_log(s, AV_LOG_ERROR, "could not find COMM tag or invalid block_align value\n");
          return -1;
      }
  
      /* Now positioned, get the sound data start and end */
      avpriv_set_pts_info(st, 64, 1, st->codecpar->sample_rate);
      st->start_time = 0;
      st->duration = st->nb_frames * aiff->block_duration;
  
      /* Position the stream at the first block */
      avio_seek(pb, offset, SEEK_SET);
  
      return 0;
  }
  
  #define MAX_SIZE 4096
  
  static int aiff_read_packet(AVFormatContext *s,
                              AVPacket *pkt)
  {
      AVStream *st = s->streams[0];
      AIFFInputContext *aiff = s->priv_data;
      int64_t max_size;
      int res, size;
  
      /* calculate size of remaining data */
      max_size = aiff->data_end - avio_tell(s->pb);
      if (max_size <= 0)
          return AVERROR_EOF;
  
      /* Now for that packet */
      switch (st->codecpar->codec_id) {
      case AV_CODEC_ID_ADPCM_IMA_QT:
      case AV_CODEC_ID_GSM:
      case AV_CODEC_ID_QDM2:
      case AV_CODEC_ID_QCELP:
          size = st->codecpar->block_align;
          break;
      default:
          size = (MAX_SIZE / st->codecpar->block_align) * st->codecpar->block_align;
      }
      size = FFMIN(max_size, size);
      res = av_get_packet(s->pb, pkt, size);
      if (res < 0)
          return res;
  
      if (size >= st->codecpar->block_align)
          pkt->flags &= ~AV_PKT_FLAG_CORRUPT;
      /* Only one stream in an AIFF file */
      pkt->stream_index = 0;
      pkt->duration     = (res / st->codecpar->block_align) * aiff->block_duration;
      return 0;
  }
  
  AVInputFormat ff_aiff_demuxer = {
      .name           = "aiff",
      .long_name      = NULL_IF_CONFIG_SMALL("Audio IFF"),
      .priv_data_size = sizeof(AIFFInputContext),
      .read_probe     = aiff_probe,
      .read_header    = aiff_read_header,
      .read_packet    = aiff_read_packet,
      .read_seek      = ff_pcm_read_seek,
      .codec_tag      = (const AVCodecTag* const []){ ff_codec_aiff_tags, 0 },
  };
  