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  snd__TAG MKTAG('s', 'n', 'd', '_')
  48
  49 #define vtrk_SIZE 0x44
  50 #define strk_SIZE 0x28
  51
  52 #define GET_LIST_HEADER() \
  53     fourcc_tag = get_le32(pb); \
  54     size = get_le32(pb); \
  55     if (fourcc_tag != LIST_TAG) \
  56         return AVERROR_INVALIDDATA; \
  57     fourcc_tag = get_le32(pb);
  58
  59 typedef struct AudioTrack {
  60     int sample_rate;
  61     int bits;
  62     int channels;
  63     int stream_index;
  64     int adpcm;
  65 } AudioTrack;
  66
  67 typedef struct FourxmDemuxContext {
  68     int width;
  69     int height;
  70     int video_stream_index;
  71     int track_count;
  72     AudioTrack *tracks;
  73     int selected_track;
  74
  75     int64_t audio_pts;
  76     int64_t video_pts;
  77     float fps;
  78 } FourxmDemuxContext;
  79
  80 static int fourxm_probe(AVProbeData *p)
  81 {
  82     if (p->buf_size < 12)
  83         return 0;
  84
  85     if ((LE_32(&p->buf[0]) != RIFF_TAG) ||
  86         (LE_32(&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 = (FourxmDemuxContext *)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_NOMEM;
 123     if (get_buffer(pb, header, header_size) != header_size)
 124         return AVERROR_IO;
 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 = LE_32(&header[i]);
 129         size = LE_32(&header[i + 4]);
 130
 131         if (fourcc_tag == std__TAG) {
 132             fourxm->fps = av_int2flt(LE_32(&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 = LE_32(&header[i + 36]);
 140             fourxm->height = LE_32(&header[i + 40]);
 141             i += 8 + size;
 142
 143             /* allocate a new AVStream */
 144             st = av_new_stream(s, 0);
 145             if (!st)
 146                 return AVERROR_NOMEM;
 147             av_set_pts_info(st, 60, 1, fourxm->fps);
 148
 149             fourxm->video_stream_index = st->index;
 150
 151             st->codec->codec_type = CODEC_TYPE_VIDEO;
 152             st->codec->codec_id = CODEC_ID_4XM;
 153             st->codec->codec_tag = 0;  /* no fourcc */
 154             st->codec->width = fourxm->width;
 155             st->codec->height = fourxm->height;
 156
 157         } else if (fourcc_tag == strk_TAG) {
 158             /* check that there is enough data */
 159             if (size != strk_SIZE) {
 160                 av_free(header);
 161                 return AVERROR_INVALIDDATA;
 162             }
 163             current_track = LE_32(&header[i + 8]);
 164             if (current_track + 1 > fourxm->track_count) {
 165                 fourxm->track_count = current_track + 1;
 166                 if((unsigned)fourxm->track_count >= UINT_MAX / sizeof(AudioTrack))
 167                     return -1;
 168                 fourxm->tracks = av_realloc(fourxm->tracks,
 169                     fourxm->track_count * sizeof(AudioTrack));
 170                 if (!fourxm->tracks) {
 171                     av_free(header);
 172                     return AVERROR_NOMEM;
 173                 }
 174             }
 175             fourxm->tracks[current_track].adpcm = LE_32(&header[i + 12]);
 176             fourxm->tracks[current_track].channels = LE_32(&header[i + 36]);
 177             fourxm->tracks[current_track].sample_rate = LE_32(&header[i + 40]);
 178             fourxm->tracks[current_track].bits = LE_32(&header[i + 44]);
 179             i += 8 + size;
 180
 181             /* allocate a new AVStream */
 182             st = av_new_stream(s, current_track);
 183             if (!st)
 184                 return AVERROR_NOMEM;
 185
 186             av_set_pts_info(st, 60, 1, fourxm->tracks[current_track].sample_rate);
 187
 188             fourxm->tracks[current_track].stream_index = st->index;
 189
 190             st->codec->codec_type = CODEC_TYPE_AUDIO;
 191             st->codec->codec_tag = 0;
 192             st->codec->channels = fourxm->tracks[current_track].channels;
 193             st->codec->sample_rate = fourxm->tracks[current_track].sample_rate;
 194             st->codec->bits_per_sample = fourxm->tracks[current_track].bits;
 195             st->codec->bit_rate = st->codec->channels * st->codec->sample_rate *
 196                 st->codec->bits_per_sample;
 197             st->codec->block_align = st->codec->channels * st->codec->bits_per_sample;
 198             if (fourxm->tracks[current_track].adpcm)
 199                 st->codec->codec_id = CODEC_ID_ADPCM_4XM;
 200             else if (st->codec->bits_per_sample == 8)
 201                 st->codec->codec_id = CODEC_ID_PCM_U8;
 202             else
 203                 st->codec->codec_id = CODEC_ID_PCM_S16LE;
 204         }
 205     }
 206
 207     av_free(header);
 208
 209     /* skip over the LIST-MOVI chunk (which is where the stream should be */
 210     GET_LIST_HEADER();
 211     if (fourcc_tag != MOVI_TAG)
 212         return AVERROR_INVALIDDATA;
 213
 214     /* initialize context members */
 215     fourxm->video_pts = -1;  /* first frame will push to 0 */
 216     fourxm->audio_pts = 0;
 217
 218     return 0;
 219 }
 220
 221 static int fourxm_read_packet(AVFormatContext *s,
 222                               AVPacket *pkt)
 223 {
 224     FourxmDemuxContext *fourxm = s->priv_data;
 225     ByteIOContext *pb = &s->pb;
 226     unsigned int fourcc_tag;
 227     unsigned int size, out_size;
 228     int ret = 0;
 229     int track_number;
 230     int packet_read = 0;
 231     unsigned char header[8];
 232     int audio_frame_count;
 233
 234     while (!packet_read) {
 235
 236         if ((ret = get_buffer(&s->pb, header, 8)) < 0)
 237             return ret;
 238         fourcc_tag = LE_32(&header[0]);
 239         size = LE_32(&header[4]);
 240         if (url_feof(pb))
 241             return AVERROR_IO;
 242         switch (fourcc_tag) {
 243
 244         case LIST_TAG:
 245             /* this is a good time to bump the video pts */
 246             fourxm->video_pts ++;
 247
 248             /* skip the LIST-* tag and move on to the next fourcc */
 249             get_le32(pb);
 250             break;
 251
 252         case ifrm_TAG:
 253         case pfrm_TAG:
 254         case cfrm_TAG:{
 255
 256             /* allocate 8 more bytes than 'size' to account for fourcc
 257              * and size */
 258             if (size + 8 < size || av_new_packet(pkt, size + 8))
 259                 return AVERROR_IO;
 260             pkt->stream_index = fourxm->video_stream_index;
 261             pkt->pts = fourxm->video_pts;
 262             pkt->pos = url_ftell(&s->pb);
 263             memcpy(pkt->data, header, 8);
 264             ret = get_buffer(&s->pb, &pkt->data[8], size);
 265
 266             if (ret < 0)
 267                 av_free_packet(pkt);
 268             else
 269                 packet_read = 1;
 270             break;
 271         }
 272
 273         case snd__TAG:
 274             track_number = get_le32(pb);
 275             out_size= get_le32(pb);
 276             size-=8;
 277
 278             if (track_number == fourxm->selected_track) {
 279                 ret= av_get_packet(&s->pb, pkt, size);
 280                 if(ret<0)
 281                     return AVERROR_IO;
 282                 pkt->stream_index =
 283                     fourxm->tracks[fourxm->selected_track].stream_index;
 284                 pkt->pts = fourxm->audio_pts;
 285                 packet_read = 1;
 286
 287                 /* pts accounting */
 288                 audio_frame_count = size;
 289                 if (fourxm->tracks[fourxm->selected_track].adpcm)
 290                     audio_frame_count -=
 291                         2 * (fourxm->tracks[fourxm->selected_track].channels);
 292                 audio_frame_count /=
 293                       fourxm->tracks[fourxm->selected_track].channels;
 294                 if (fourxm->tracks[fourxm->selected_track].adpcm)
 295                     audio_frame_count *= 2;
 296                 else
 297                     audio_frame_count /=
 298                     (fourxm->tracks[fourxm->selected_track].bits / 8);
 299                 fourxm->audio_pts += audio_frame_count;
 300
 301             } else {
 302                 url_fseek(pb, size, SEEK_CUR);
 303             }
 304             break;
 305
 306         default:
 307             url_fseek(pb, size, SEEK_CUR);
 308             break;
 309         }
 310     }
 311     return ret;
 312 }
 313
 314 static int fourxm_read_close(AVFormatContext *s)
 315 {
 316     FourxmDemuxContext *fourxm = (FourxmDemuxContext *)s->priv_data;
 317
 318     av_free(fourxm->tracks);
 319
 320     return 0;
 321 }
 322
 323 AVInputFormat fourxm_demuxer = {
 324     "4xm",
 325     "4X Technologies format",
 326     sizeof(FourxmDemuxContext),
 327     fourxm_probe,
 328     fourxm_read_header,
 329     fourxm_read_packet,
 330     fourxm_read_close,
 331 };