libavformat/4xm.c

   1 /*
   2  * 4X Technologies .4xm File Demuxer (no muxer)
   3  * Copyright (c) 2003  The ffmpeg Project
   4  *
   5  * This file is part of FFmpeg.
   6  *
   7  * FFmpeg is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU Lesser General Public
   9  * License as published by the Free Software Foundation; either
  10  * version 2.1 of the License, or (at your option) any later version.
  11  *
  12  * FFmpeg is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * Lesser General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU Lesser General Public
  18  * License along with FFmpeg; if not, write to the Free Software
  19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  20  */
  21
  22 /**
  23  * @file 4xm.c
  24  * 4X Technologies file demuxer
  25  * by Mike Melanson (melanson@pcisys.net)
  26  * for more information on the .4xm file format, visit:
  27  *   http://www.pcisys.net/~melanson/codecs/
  28  */
  29
  30 #include "avformat.h"
  31
  32 #define  RIFF_TAG MKTAG('R', 'I', 'F', 'F')
  33 #define _4XMV_TAG MKTAG('4', 'X', 'M', 'V')
  34 #define  LIST_TAG MKTAG('L', 'I', 'S', 'T')
  35 #define  HEAD_TAG MKTAG('H', 'E', 'A', 'D')
  36 #define  TRK__TAG MKTAG('T', 'R', 'K', '_')
  37 #define  MOVI_TAG MKTAG('M', 'O', 'V', 'I')
  38 #define  VTRK_TAG MKTAG('V', 'T', 'R', 'K')
  39 #define  STRK_TAG MKTAG('S', 'T', 'R', 'K')
  40 #define  std__TAG MKTAG('s', 't', 'd', '_')
  41 #define  name_TAG MKTAG('n', 'a', 'm', 'e')
  42 #define  vtrk_TAG MKTAG('v', 't', 'r', 'k')
  43 #define  strk_TAG MKTAG('s', 't', 'r', 'k')
  44 #define  ifrm_TAG MKTAG('i', 'f', 'r', 'm')
  45 #define  pfrm_TAG MKTAG('p', 'f', 'r', 'm')
  46 #define  cfrm_TAG MKTAG('c', 'f', 'r', 'm')
  47 #define  ifr2_TAG MKTAG('i', 'f', 'r', '2')
  48 #define  pfr2_TAG MKTAG('p', 'f', 'r', '2')
  49 #define  cfr2_TAG MKTAG('c', 'f', 'r', '2')
  50 #define  snd__TAG MKTAG('s', 'n', 'd', '_')
  51
  52 #define vtrk_SIZE 0x44
  53 #define strk_SIZE 0x28
  54
  55 #define GET_LIST_HEADER() \
  56     fourcc_tag = get_le32(pb); \
  57     size = get_le32(pb); \
  58     if (fourcc_tag != LIST_TAG) \
  59         return AVERROR_INVALIDDATA; \
  60     fourcc_tag = get_le32(pb);
  61
  62 typedef struct AudioTrack {
  63     int sample_rate;
  64     int bits;
  65     int channels;
  66     int stream_index;
  67     int adpcm;
  68 } AudioTrack;
  69
  70 typedef struct FourxmDemuxContext {
  71     int width;
  72     int height;
  73     int video_stream_index;
  74     int track_count;
  75     AudioTrack *tracks;
  76     int selected_track;
  77
  78     int64_t audio_pts;
  79     int64_t video_pts;
  80     float fps;
  81 } FourxmDemuxContext;
  82
  83 static int fourxm_probe(AVProbeData *p)
  84 {
  85     if ((AV_RL32(&p->buf[0]) != RIFF_TAG) ||
  86         (AV_RL32(&p->buf[8]) != _4XMV_TAG))
  87         return 0;
  88
  89     return AVPROBE_SCORE_MAX;
  90 }
  91
  92 static int fourxm_read_header(AVFormatContext *s,
  93                               AVFormatParameters *ap)
  94 {
  95     ByteIOContext *pb = s->pb;
  96     unsigned int fourcc_tag;
  97     unsigned int size;
  98     int header_size;
  99     FourxmDemuxContext *fourxm = s->priv_data;
 100     unsigned char *header;
 101     int i;
 102     int current_track = -1;
 103     AVStream *st;
 104
 105     fourxm->track_count = 0;
 106     fourxm->tracks = NULL;
 107     fourxm->selected_track = 0;
 108     fourxm->fps = 1.0;
 109
 110     /* skip the first 3 32-bit numbers */
 111     url_fseek(pb, 12, SEEK_CUR);
 112
 113     /* check for LIST-HEAD */
 114     GET_LIST_HEADER();
 115     header_size = size - 4;
 116     if (fourcc_tag != HEAD_TAG)
 117         return AVERROR_INVALIDDATA;
 118
 119     /* allocate space for the header and load the whole thing */
 120     header = av_malloc(header_size);
 121     if (!header)
 122         return AVERROR(ENOMEM);
 123     if (get_buffer(pb, header, header_size) != header_size)
 124         return AVERROR(EIO);
 125
 126     /* take the lazy approach and search for any and all vtrk and strk chunks */
 127     for (i = 0; i < header_size - 8; i++) {
 128         fourcc_tag = AV_RL32(&header[i]);
 129         size = AV_RL32(&header[i + 4]);
 130
 131         if (fourcc_tag == std__TAG) {
 132             fourxm->fps = av_int2flt(AV_RL32(&header[i + 12]));
 133         } else if (fourcc_tag == vtrk_TAG) {
 134             /* check that there is enough data */
 135             if (size != vtrk_SIZE) {
 136                 av_free(header);
 137                 return AVERROR_INVALIDDATA;
 138             }
 139             fourxm->width = AV_RL32(&header[i + 36]);
 140             fourxm->height = AV_RL32(&header[i + 40]);
 141
 142             /* allocate a new AVStream */
 143             st = av_new_stream(s, 0);
 144             if (!st)
 145                 return AVERROR(ENOMEM);
 146             av_set_pts_info(st, 60, 1, fourxm->fps);
 147
 148             fourxm->video_stream_index = st->index;
 149
 150             st->codec->codec_type = CODEC_TYPE_VIDEO;
 151             st->codec->codec_id = CODEC_ID_4XM;
 152             st->codec->extradata_size = 4;
 153             st->codec->extradata = av_malloc(4);
 154             AV_WL32(st->codec->extradata, AV_RL32(&header[i + 16]));
 155             st->codec->width = fourxm->width;
 156             st->codec->height = fourxm->height;
 157
 158             i += 8 + size;
 159         } else if (fourcc_tag == strk_TAG) {
 160             /* check that there is enough data */
 161             if (size != strk_SIZE) {
 162                 av_free(header);
 163                 return AVERROR_INVALIDDATA;
 164             }
 165             current_track = AV_RL32(&header[i + 8]);
 166             if (current_track + 1 > fourxm->track_count) {
 167                 fourxm->track_count = current_track + 1;
 168                 if((unsigned)fourxm->track_count >= UINT_MAX / sizeof(AudioTrack))
 169                     return -1;
 170                 fourxm->tracks = av_realloc(fourxm->tracks,
 171                     fourxm->track_count * sizeof(AudioTrack));
 172                 if (!fourxm->tracks) {
 173                     av_free(header);
 174                     return AVERROR(ENOMEM);
 175                 }
 176             }
 177             fourxm->tracks[current_track].adpcm = AV_RL32(&header[i + 12]);
 178             fourxm->tracks[current_track].channels = AV_RL32(&header[i + 36]);
 179             fourxm->tracks[current_track].sample_rate = AV_RL32(&header[i + 40]);
 180             fourxm->tracks[current_track].bits = AV_RL32(&header[i + 44]);
 181             i += 8 + size;
 182
 183             /* allocate a new AVStream */
 184             st = av_new_stream(s, current_track);
 185             if (!st)
 186                 return AVERROR(ENOMEM);
 187
 188             av_set_pts_info(st, 60, 1, fourxm->tracks[current_track].sample_rate);
 189
 190             fourxm->tracks[current_track].stream_index = st->index;
 191
 192             st->codec->codec_type = CODEC_TYPE_AUDIO;
 193             st->codec->codec_tag = 0;
 194             st->codec->channels = fourxm->tracks[current_track].channels;
 195             st->codec->sample_rate = fourxm->tracks[current_track].sample_rate;
 196             st->codec->bits_per_coded_sample = fourxm->tracks[current_track].bits;
 197             st->codec->bit_rate = st->codec->channels * st->codec->sample_rate *
 198                 st->codec->bits_per_coded_sample;
 199             st->codec->block_align = st->codec->channels * st->codec->bits_per_coded_sample;
 200             if (fourxm->tracks[current_track].adpcm)
 201                 st->codec->codec_id = CODEC_ID_ADPCM_4XM;
 202             else if (st->codec->bits_per_coded_sample == 8)
 203                 st->codec->codec_id = CODEC_ID_PCM_U8;
 204             else
 205                 st->codec->codec_id = CODEC_ID_PCM_S16LE;
 206         }
 207     }
 208
 209     av_free(header);
 210
 211     /* skip over the LIST-MOVI chunk (which is where the stream should be */
 212     GET_LIST_HEADER();
 213     if (fourcc_tag != MOVI_TAG)
 214         return AVERROR_INVALIDDATA;
 215
 216     /* initialize context members */
 217     fourxm->video_pts = -1;  /* first frame will push to 0 */
 218     fourxm->audio_pts = 0;
 219
 220     return 0;
 221 }
 222
 223 static int fourxm_read_packet(AVFormatContext *s,
 224                               AVPacket *pkt)
 225 {
 226     FourxmDemuxContext *fourxm = s->priv_data;
 227     ByteIOContext *pb = s->pb;
 228     unsigned int fourcc_tag;
 229     unsigned int size, out_size;
 230     int ret = 0;
 231     int track_number;
 232     int packet_read = 0;
 233     unsigned char header[8];
 234     int audio_frame_count;
 235
 236     while (!packet_read) {
 237
 238         if ((ret = get_buffer(s->pb, header, 8)) < 0)
 239             return ret;
 240         fourcc_tag = AV_RL32(&header[0]);
 241         size = AV_RL32(&header[4]);
 242         if (url_feof(pb))
 243             return AVERROR(EIO);
 244         switch (fourcc_tag) {
 245
 246         case LIST_TAG:
 247             /* this is a good time to bump the video pts */
 248             fourxm->video_pts ++;
 249
 250             /* skip the LIST-* tag and move on to the next fourcc */
 251             get_le32(pb);
 252             break;
 253
 254         case ifrm_TAG:
 255         case pfrm_TAG:
 256         case cfrm_TAG:
 257         case ifr2_TAG:
 258         case pfr2_TAG:
 259         case cfr2_TAG:
 260         {
 261
 262             /* allocate 8 more bytes than 'size' to account for fourcc
 263              * and size */
 264             if (size + 8 < size || av_new_packet(pkt, size + 8))
 265                 return AVERROR(EIO);
 266             pkt->stream_index = fourxm->video_stream_index;
 267             pkt->pts = fourxm->video_pts;
 268             pkt->pos = url_ftell(s->pb);
 269             memcpy(pkt->data, header, 8);
 270             ret = get_buffer(s->pb, &pkt->data[8], size);
 271
 272             if (ret < 0)
 273                 av_free_packet(pkt);
 274             else
 275                 packet_read = 1;
 276             break;
 277         }
 278
 279         case snd__TAG:
 280             track_number = get_le32(pb);
 281             out_size= get_le32(pb);
 282             size-=8;
 283
 284             if (track_number == fourxm->selected_track) {
 285                 ret= av_get_packet(s->pb, pkt, size);
 286                 if(ret<0)
 287                     return AVERROR(EIO);
 288                 pkt->stream_index =
 289                     fourxm->tracks[fourxm->selected_track].stream_index;
 290                 pkt->pts = fourxm->audio_pts;
 291                 packet_read = 1;
 292
 293                 /* pts accounting */
 294                 audio_frame_count = size;
 295                 if (fourxm->tracks[fourxm->selected_track].adpcm)
 296                     audio_frame_count -=
 297                         2 * (fourxm->tracks[fourxm->selected_track].channels);
 298                 audio_frame_count /=
 299                       fourxm->tracks[fourxm->selected_track].channels;
 300                 if (fourxm->tracks[fourxm->selected_track].adpcm)
 301                     audio_frame_count *= 2;
 302                 else
 303                     audio_frame_count /=
 304                     (fourxm->tracks[fourxm->selected_track].bits / 8);
 305                 fourxm->audio_pts += audio_frame_count;
 306
 307             } else {
 308                 url_fseek(pb, size, SEEK_CUR);
 309             }
 310             break;
 311
 312         default:
 313             url_fseek(pb, size, SEEK_CUR);
 314             break;
 315         }
 316     }
 317     return ret;
 318 }
 319
 320 static int fourxm_read_close(AVFormatContext *s)
 321 {
 322     FourxmDemuxContext *fourxm = s->priv_data;
 323
 324     av_free(fourxm->tracks);
 325
 326     return 0;
 327 }
 328
 329 AVInputFormat fourxm_demuxer = {
 330     "4xm",
 331     NULL_IF_CONFIG_SMALL("4X Technologies format"),
 332     sizeof(FourxmDemuxContext),
 333     fourxm_probe,
 334     fourxm_read_header,
 335     fourxm_read_packet,
 336     fourxm_read_close,
 337 };