libavformat/4xm.c

   1 /*
   2  * 4X Technologies .4xm File Demuxer (no muxer)
   3  * Copyright (c) 2003  The ffmpeg Project
   4  *
   5  * This library is free software; you can redistribute it and/or
   6  * modify it under the terms of the GNU Lesser General Public
   7  * License as published by the Free Software Foundation; either
   8  * version 2 of the License, or (at your option) any later version.
   9  *
  10  * This library is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13  * Lesser General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU Lesser General Public
  16  * License along with this library; if not, write to the Free Software
  17  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  18  */
  19
  20 /**
  21  * @file 4xm.c
  22  * 4X Technologies file demuxer
  23  * by Mike Melanson (melanson@pcisys.net)
  24  * for more information on the .4xm file format, visit:
  25  *   http://www.pcisys.net/~melanson/codecs/
  26  */
  27
  28 #include "avformat.h"
  29
  30 #define LE_16(x)  ((((uint8_t*)(x))[1] << 8) | ((uint8_t*)(x))[0])
  31 #define LE_32(x)  ((((uint8_t*)(x))[3] << 24) | \
  32                    (((uint8_t*)(x))[2] << 16) | \
  33                    (((uint8_t*)(x))[1] << 8) | \
  34                     ((uint8_t*)(x))[0])
  35
  36 #define FOURCC_TAG( ch0, ch1, ch2, ch3 ) \
  37         ( (long)(unsigned char)(ch0) | \
  38         ( (long)(unsigned char)(ch1) << 8 ) | \
  39         ( (long)(unsigned char)(ch2) << 16 ) | \
  40         ( (long)(unsigned char)(ch3) << 24 ) )
  41
  42 #define  RIFF_TAG FOURCC_TAG('R', 'I', 'F', 'F')
  43 #define _4XMV_TAG FOURCC_TAG('4', 'X', 'M', 'V')
  44 #define  LIST_TAG FOURCC_TAG('L', 'I', 'S', 'T')
  45 #define  HEAD_TAG FOURCC_TAG('H', 'E', 'A', 'D')
  46 #define  TRK__TAG FOURCC_TAG('T', 'R', 'K', '_')
  47 #define  MOVI_TAG FOURCC_TAG('M', 'O', 'V', 'I')
  48 #define  VTRK_TAG FOURCC_TAG('V', 'T', 'R', 'K')
  49 #define  STRK_TAG FOURCC_TAG('S', 'T', 'R', 'K')
  50 #define  std__TAG FOURCC_TAG('s', 't', 'd', '_')
  51 #define  name_TAG FOURCC_TAG('n', 'a', 'm', 'e')
  52 #define  vtrk_TAG FOURCC_TAG('v', 't', 'r', 'k')
  53 #define  strk_TAG FOURCC_TAG('s', 't', 'r', 'k')
  54 #define  ifrm_TAG FOURCC_TAG('i', 'f', 'r', 'm')
  55 #define  pfrm_TAG FOURCC_TAG('p', 'f', 'r', 'm')
  56 #define  cfrm_TAG FOURCC_TAG('c', 'f', 'r', 'm')
  57 #define  snd__TAG FOURCC_TAG('s', 'n', 'd', '_')
  58 #define  _TAG FOURCC_TAG('', '', '', '')
  59
  60 #define vtrk_SIZE 0x44
  61 #define strk_SIZE 0x28
  62
  63 #define GET_LIST_HEADER() \
  64     fourcc_tag = get_le32(pb); \
  65     size = get_le32(pb); \
  66     if (fourcc_tag != LIST_TAG) \
  67         return AVERROR_INVALIDDATA; \
  68     fourcc_tag = get_le32(pb);
  69
  70 typedef struct AudioTrack {
  71     int sample_rate;
  72     int bits;
  73     int channels;
  74     int stream_index;
  75     int adpcm;
  76 } AudioTrack;
  77
  78 typedef struct FourxmDemuxContext {
  79     int width;
  80     int height;
  81     int video_stream_index;
  82     int track_count;
  83     AudioTrack *tracks;
  84     int selected_track;
  85
  86     int64_t audio_pts;
  87     int64_t video_pts;
  88     int video_pts_inc;
  89 } FourxmDemuxContext;
  90
  91 static float get_le_float(unsigned char *buffer)
  92 {
  93     float f;
  94     unsigned char *float_buffer = (unsigned char *)&f;
  95
  96 #ifdef WORDS_BIGENDIAN
  97     float_buffer[0] = buffer[3];
  98     float_buffer[1] = buffer[2];
  99     float_buffer[2] = buffer[1];
 100     float_buffer[3] = buffer[0];
 101 #else
 102     float_buffer[0] = buffer[0];
 103     float_buffer[1] = buffer[1];
 104     float_buffer[2] = buffer[2];
 105     float_buffer[3] = buffer[3];
 106 #endif
 107
 108     return f;
 109 }
 110
 111 static int fourxm_probe(AVProbeData *p)
 112 {
 113     if (p->buf_size < 12)
 114         return 0;
 115
 116     if ((LE_32(&p->buf[0]) != RIFF_TAG) ||
 117         (LE_32(&p->buf[8]) != _4XMV_TAG))
 118         return 0;
 119
 120     return AVPROBE_SCORE_MAX;
 121 }
 122
 123 static int fourxm_read_header(AVFormatContext *s,
 124                               AVFormatParameters *ap)
 125 {
 126     ByteIOContext *pb = &s->pb;
 127     unsigned int fourcc_tag;
 128     unsigned int size;
 129     int header_size;
 130     FourxmDemuxContext *fourxm = (FourxmDemuxContext *)s->priv_data;
 131     unsigned char *header;
 132     int i;
 133     int current_track = -1;
 134     AVStream *st;
 135     float fps;
 136
 137     fourxm->track_count = 0;
 138     fourxm->tracks = NULL;
 139     fourxm->selected_track = 0;
 140
 141     /* skip the first 3 32-bit numbers */
 142     url_fseek(pb, 12, SEEK_CUR);
 143
 144     /* check for LIST-HEAD */
 145     GET_LIST_HEADER();
 146     header_size = size - 4;
 147     if (fourcc_tag != HEAD_TAG)
 148         return AVERROR_INVALIDDATA;
 149
 150     /* allocate space for the header and load the whole thing */
 151     header = av_malloc(header_size);
 152     if (!header)
 153         return AVERROR_NOMEM;
 154     if (get_buffer(pb, header, header_size) != header_size)
 155         return AVERROR_IO;
 156
 157     /* take the lazy approach and search for any and all vtrk and strk chunks */
 158     for (i = 0; i < header_size - 8; i++) {
 159         fourcc_tag = LE_32(&header[i]);
 160         size = LE_32(&header[i + 4]);
 161
 162         if (fourcc_tag == std__TAG) {
 163             fps = get_le_float(&header[i + 12]);
 164             fourxm->video_pts_inc = (int)(90000.0 / fps);
 165         } else if (fourcc_tag == vtrk_TAG) {
 166             /* check that there is enough data */
 167             if (size != vtrk_SIZE) {
 168                 av_free(header);
 169                 return AVERROR_INVALIDDATA;
 170             }
 171             fourxm->width = LE_32(&header[i + 36]);
 172             fourxm->height = LE_32(&header[i + 40]);
 173             i += 8 + size;
 174
 175             /* allocate a new AVStream */
 176             st = av_new_stream(s, 0);
 177             if (!st)
 178                 return AVERROR_NOMEM;
 179
 180             fourxm->video_stream_index = st->index;
 181
 182             st->codec.codec_type = CODEC_TYPE_VIDEO;
 183             st->codec.codec_id = CODEC_ID_4XM;
 184             st->codec.codec_tag = 0;  /* no fourcc */
 185             st->codec.width = fourxm->width;
 186             st->codec.height = fourxm->height;
 187
 188         } else if (fourcc_tag == strk_TAG) {
 189             /* check that there is enough data */
 190             if (size != strk_SIZE) {
 191                 av_free(header);
 192                 return AVERROR_INVALIDDATA;
 193             }
 194             current_track = LE_32(&header[i + 8]);
 195             if (current_track + 1 > fourxm->track_count) {
 196                 fourxm->track_count = current_track + 1;
 197                 fourxm->tracks = av_realloc(fourxm->tracks,
 198                     fourxm->track_count * sizeof(AudioTrack));
 199                 if (!fourxm->tracks) {
 200                     av_free(header);
 201                     return AVERROR_NOMEM;
 202                 }
 203             }
 204             fourxm->tracks[current_track].adpcm = LE_32(&header[i + 12]);
 205             fourxm->tracks[current_track].channels = LE_32(&header[i + 36]);
 206             fourxm->tracks[current_track].sample_rate = LE_32(&header[i + 40]);
 207             fourxm->tracks[current_track].bits = LE_32(&header[i + 44]);
 208             i += 8 + size;
 209
 210             /* allocate a new AVStream */
 211             st = av_new_stream(s, current_track);
 212             if (!st)
 213                 return AVERROR_NOMEM;
 214
 215             fourxm->tracks[current_track].stream_index = st->index;
 216
 217             st->codec.codec_type = CODEC_TYPE_AUDIO;
 218             st->codec.codec_tag = 1;
 219             st->codec.channels = fourxm->tracks[current_track].channels;
 220             st->codec.sample_rate = fourxm->tracks[current_track].sample_rate;
 221             st->codec.bits_per_sample = fourxm->tracks[current_track].bits;
 222             st->codec.bit_rate = st->codec.channels * st->codec.sample_rate *
 223                 st->codec.bits_per_sample;
 224             st->codec.block_align = st->codec.channels * st->codec.bits_per_sample;
 225             if (fourxm->tracks[current_track].adpcm)
 226                 st->codec.codec_id = CODEC_ID_ADPCM_4XM;
 227             else if (st->codec.bits_per_sample == 8)
 228                 st->codec.codec_id = CODEC_ID_PCM_U8;
 229             else
 230                 st->codec.codec_id = CODEC_ID_PCM_S16LE;
 231         }
 232     }
 233
 234     av_free(header);
 235
 236     /* skip over the LIST-MOVI chunk (which is where the stream should be */
 237     GET_LIST_HEADER();
 238     if (fourcc_tag != MOVI_TAG)
 239         return AVERROR_INVALIDDATA;
 240
 241     /* initialize context members */
 242     fourxm->video_pts = -fourxm->video_pts_inc;  /* first frame will push to 0 */
 243     fourxm->audio_pts = 0;
 244
 245     /* set the pts reference (1 pts = 1/90000) */
 246     s->pts_num = 1;
 247     s->pts_den = 90000;
 248
 249     return 0;
 250 }
 251
 252 static int fourxm_read_packet(AVFormatContext *s,
 253                               AVPacket *pkt)
 254 {
 255     FourxmDemuxContext *fourxm = s->priv_data;
 256     ByteIOContext *pb = &s->pb;
 257     unsigned int fourcc_tag;
 258     unsigned int size, out_size;
 259     int ret = 0;
 260     int track_number;
 261     int packet_read = 0;
 262     unsigned char header[8];
 263     int64_t pts_inc;
 264     int audio_frame_count;
 265
 266     while (!packet_read) {
 267
 268         if ((ret = get_buffer(&s->pb, header, 8)) < 0)
 269             return ret;
 270         fourcc_tag = LE_32(&header[0]);
 271         size = LE_32(&header[4]);
 272         if (url_feof(pb))
 273             return -EIO;
 274         switch (fourcc_tag) {
 275
 276         case LIST_TAG:
 277             /* this is a good time to bump the video pts */
 278             fourxm->video_pts += fourxm->video_pts_inc;
 279
 280             /* skip the LIST-* tag and move on to the next fourcc */
 281             get_le32(pb);
 282             break;
 283
 284         case ifrm_TAG:
 285         case pfrm_TAG:
 286         case cfrm_TAG:{
 287
 288             /* allocate 8 more bytes than 'size' to account for fourcc
 289              * and size */
 290             if (av_new_packet(pkt, size + 8))
 291                 return -EIO;
 292             pkt->stream_index = fourxm->video_stream_index;
 293             pkt->pts = fourxm->video_pts;
 294             memcpy(pkt->data, header, 8);
 295             ret = get_buffer(&s->pb, &pkt->data[8], size);
 296
 297             if (ret < 0)
 298                 av_free_packet(pkt);
 299             else
 300                 packet_read = 1;
 301             break;
 302         }
 303
 304         case snd__TAG:
 305             track_number = get_le32(pb);
 306             out_size= get_le32(pb);
 307             size-=8;
 308
 309             if (track_number == fourxm->selected_track) {
 310                 if (av_new_packet(pkt, size))
 311                     return -EIO;
 312                 pkt->stream_index =
 313                     fourxm->tracks[fourxm->selected_track].stream_index;
 314                 pkt->pts = fourxm->audio_pts;
 315                 ret = get_buffer(&s->pb, pkt->data, size);
 316                 if (ret < 0)
 317                     av_free_packet(pkt);
 318                 else
 319                     packet_read = 1;
 320
 321                 /* pts accounting */
 322                 audio_frame_count = size;
 323                 if (fourxm->tracks[fourxm->selected_track].adpcm)
 324                     audio_frame_count -=
 325                         2 * (fourxm->tracks[fourxm->selected_track].channels);
 326                 audio_frame_count /=
 327                       fourxm->tracks[fourxm->selected_track].channels;
 328                 if (fourxm->tracks[fourxm->selected_track].adpcm)
 329                     audio_frame_count *= 2;
 330                 else
 331                     audio_frame_count /=
 332                     (fourxm->tracks[fourxm->selected_track].bits / 8);
 333                 pts_inc = audio_frame_count;
 334                 pts_inc *= 90000;
 335                 pts_inc /= fourxm->tracks[fourxm->selected_track].sample_rate;
 336                 fourxm->audio_pts += pts_inc;
 337
 338             } else {
 339                 url_fseek(pb, size, SEEK_CUR);
 340             }
 341             break;
 342
 343         default:
 344             url_fseek(pb, size, SEEK_CUR);
 345             break;
 346         }
 347     }
 348     return ret;
 349 }
 350
 351 static int fourxm_read_close(AVFormatContext *s)
 352 {
 353     FourxmDemuxContext *fourxm = (FourxmDemuxContext *)s->priv_data;
 354
 355     av_free(fourxm->tracks);
 356
 357     return 0;
 358 }
 359
 360 static AVInputFormat fourxm_iformat = {
 361     "4xm",
 362     "4X Technologies format",
 363     sizeof(FourxmDemuxContext),
 364     fourxm_probe,
 365     fourxm_read_header,
 366     fourxm_read_packet,
 367     fourxm_read_close,
 368 };
 369
 370 int fourxm_init(void)
 371 {
 372     av_register_input_format(&fourxm_iformat);
 373     return 0;
 374 }