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  name_TAG FOURCC_TAG('n', 'a', 'm', 'e')
  51 #define  vtrk_TAG FOURCC_TAG('v', 't', 'r', 'k')
  52 #define  strk_TAG FOURCC_TAG('s', 't', 'r', 'k')
  53 #define  ifrm_TAG FOURCC_TAG('i', 'f', 'r', 'm')
  54 #define  pfrm_TAG FOURCC_TAG('p', 'f', 'r', 'm')
  55 #define  cfrm_TAG FOURCC_TAG('c', 'f', 'r', 'm')
  56 #define  snd__TAG FOURCC_TAG('s', 'n', 'd', '_')
  57 #define  _TAG FOURCC_TAG('', '', '', '')
  58
  59 #define vtrk_SIZE 0x44
  60 #define strk_SIZE 0x28
  61
  62 #define GET_LIST_HEADER() \
  63     fourcc_tag = get_le32(pb); \
  64     size = get_le32(pb); \
  65     if (fourcc_tag != LIST_TAG) \
  66         return AVERROR_INVALIDDATA; \
  67     fourcc_tag = get_le32(pb);
  68
  69 typedef struct AudioTrack {
  70     int sample_rate;
  71     int bits;
  72     int channels;
  73     int stream_index;
  74     int adpcm;
  75 } AudioTrack;
  76
  77 typedef struct FourxmDemuxContext {
  78     int width;
  79     int height;
  80     int video_stream_index;
  81     int track_count;
  82     AudioTrack *tracks;
  83     int selected_track;
  84
  85     int64_t pts;
  86     int last_chunk_was_audio;
  87     int last_audio_frame_count;
  88 } FourxmDemuxContext;
  89
  90 static int fourxm_probe(AVProbeData *p)
  91 {
  92     if (p->buf_size < 12)
  93         return 0;
  94
  95     if ((LE_32(&p->buf[0]) != RIFF_TAG) ||
  96         (LE_32(&p->buf[8]) != _4XMV_TAG))
  97         return 0;
  98
  99     return AVPROBE_SCORE_MAX;
 100 }
 101
 102 static int fourxm_read_header(AVFormatContext *s,
 103                               AVFormatParameters *ap)
 104 {
 105     ByteIOContext *pb = &s->pb;
 106     unsigned int fourcc_tag;
 107     unsigned int size;
 108     int header_size;
 109     FourxmDemuxContext *fourxm = (FourxmDemuxContext *)s->priv_data;
 110     unsigned char *header;
 111     int i;
 112     int current_track = -1;
 113     AVStream *st;
 114
 115     fourxm->track_count = 0;
 116     fourxm->tracks = NULL;
 117     fourxm->selected_track = 0;
 118
 119     /* skip the first 3 32-bit numbers */
 120     url_fseek(pb, 12, SEEK_CUR);
 121
 122     /* check for LIST-HEAD */
 123     GET_LIST_HEADER();
 124     header_size = size - 4;
 125     if (fourcc_tag != HEAD_TAG)
 126         return AVERROR_INVALIDDATA;
 127
 128     /* allocate space for the header and load the whole thing */
 129     header = av_malloc(header_size);
 130     if (!header)
 131         return AVERROR_NOMEM;
 132     if (get_buffer(pb, header, header_size) != header_size)
 133         return AVERROR_IO;
 134
 135     /* take the lazy approach and search for any and all vtrk and strk chunks */
 136     for (i = 0; i < header_size - 8; i++) {
 137         fourcc_tag = LE_32(&header[i]);
 138         size = LE_32(&header[i + 4]);
 139
 140         if (fourcc_tag == vtrk_TAG) {
 141             /* check that there is enough data */
 142             if (size != vtrk_SIZE) {
 143                 av_free(header);
 144                 return AVERROR_INVALIDDATA;
 145             }
 146             fourxm->width = LE_32(&header[i + 36]);
 147             fourxm->height = LE_32(&header[i + 40]);
 148             i += 8 + size;
 149
 150             /* allocate a new AVStream */
 151             st = av_new_stream(s, 0);
 152             if (!st)
 153                 return AVERROR_NOMEM;
 154
 155             fourxm->video_stream_index = st->index;
 156
 157             st->codec.codec_type = CODEC_TYPE_VIDEO;
 158             st->codec.codec_id = CODEC_ID_4XM;
 159             st->codec.codec_tag = 0;  /* no fourcc */
 160             st->codec.width = fourxm->width;
 161             st->codec.height = fourxm->height;
 162
 163         } else if (fourcc_tag == strk_TAG) {
 164             /* check that there is enough data */
 165             if (size != strk_SIZE) {
 166                 av_free(header);
 167                 return AVERROR_INVALIDDATA;
 168             }
 169             current_track = LE_32(&header[i + 8]);
 170             if (current_track + 1 > fourxm->track_count) {
 171                 fourxm->track_count = current_track + 1;
 172                 fourxm->tracks = av_realloc(fourxm->tracks,
 173                     fourxm->track_count * sizeof(AudioTrack));
 174                 if (!fourxm->tracks) {
 175                     av_free(header);
 176                     return AVERROR_NOMEM;
 177                 }
 178             }
 179             fourxm->tracks[current_track].adpcm = LE_32(&header[i + 12]);
 180             fourxm->tracks[current_track].channels = LE_32(&header[i + 36]);
 181             fourxm->tracks[current_track].sample_rate = LE_32(&header[i + 40]);
 182             fourxm->tracks[current_track].bits = LE_32(&header[i + 44]);
 183             printf("bps:%d\n", fourxm->tracks[current_track].bits);
 184             i += 8 + size;
 185
 186             /* allocate a new AVStream */
 187             st = av_new_stream(s, current_track);
 188             if (!st)
 189                 return AVERROR_NOMEM;
 190
 191             fourxm->tracks[current_track].stream_index = st->index;
 192
 193             st->codec.codec_type = CODEC_TYPE_AUDIO;
 194             st->codec.codec_tag = 1;
 195             st->codec.channels = fourxm->tracks[current_track].channels;
 196             st->codec.sample_rate = fourxm->tracks[current_track].sample_rate;
 197             st->codec.bits_per_sample = fourxm->tracks[current_track].bits;
 198             st->codec.bit_rate = st->codec.channels * st->codec.sample_rate *
 199                 st->codec.bits_per_sample;
 200             st->codec.block_align = st->codec.channels * st->codec.bits_per_sample;
 201             if (fourxm->tracks[current_track].adpcm)
 202                 st->codec.codec_id = CODEC_ID_ADPCM_4XM;
 203             else if (st->codec.bits_per_sample == 8)
 204                 st->codec.codec_id = CODEC_ID_PCM_U8;
 205             else
 206                 st->codec.codec_id = CODEC_ID_PCM_S16LE;
 207         }
 208     }
 209
 210     av_free(header);
 211
 212     /* skip over the LIST-MOVI chunk (which is where the stream should be */
 213     GET_LIST_HEADER();
 214     if (fourcc_tag != MOVI_TAG)
 215         return AVERROR_INVALIDDATA;
 216
 217     /* initialize context members */
 218     fourxm->pts = 0;
 219     fourxm->last_chunk_was_audio = 0;
 220     fourxm->last_audio_frame_count = 0;
 221
 222     /* set the pts reference (1 pts = 1/90000) */
 223     s->pts_num = 1;
 224     s->pts_den = 90000;
 225
 226     return 0;
 227 }
 228
 229 static int fourxm_read_packet(AVFormatContext *s,
 230                               AVPacket *pkt)
 231 {
 232     FourxmDemuxContext *fourxm = s->priv_data;
 233     ByteIOContext *pb = &s->pb;
 234     unsigned int fourcc_tag;
 235     unsigned int size, out_size;
 236     int ret = 0;
 237     int track_number;
 238     int packet_read = 0;
 239     unsigned char header[8];
 240     int64_t pts_inc;
 241
 242     while (!packet_read) {
 243
 244         if ((ret = get_buffer(&s->pb, header, 8)) < 0)
 245             return ret;
 246         fourcc_tag = LE_32(&header[0]);
 247         size = LE_32(&header[4]);
 248         if (url_feof(pb))
 249             return -EIO;
 250         switch (fourcc_tag) {
 251
 252         case LIST_TAG:
 253             /* skip the LIST-* tag and move on to the next fourcc */
 254             get_le32(pb);
 255             break;
 256
 257         case ifrm_TAG:
 258         case pfrm_TAG:
 259         case cfrm_TAG:{
 260
 261             /* bump the pts if the last data sent out was audio */
 262             if (fourxm->last_chunk_was_audio) {
 263                 fourxm->last_chunk_was_audio = 0;
 264                 pts_inc = fourxm->last_audio_frame_count;
 265                 pts_inc *= 90000;
 266                 pts_inc /= fourxm->tracks[fourxm->selected_track].sample_rate;
 267                 fourxm->pts += pts_inc;
 268             }
 269
 270             /* allocate 8 more bytes than 'size' to account for fourcc
 271              * and size */
 272             if (av_new_packet(pkt, size + 8))
 273                 return -EIO;
 274             pkt->stream_index = fourxm->video_stream_index;
 275             pkt->pts = fourxm->pts;
 276             memcpy(pkt->data, header, 8);
 277             ret = get_buffer(&s->pb, &pkt->data[8], size);
 278
 279             if (ret < 0)
 280                 av_free_packet(pkt);
 281             else
 282                 packet_read = 1;
 283             break;
 284         }
 285
 286         case snd__TAG:
 287             track_number = get_le32(pb);
 288             out_size= get_le32(pb);
 289             size-=8;
 290
 291             if (track_number == fourxm->selected_track) {
 292                 if (av_new_packet(pkt, size))
 293                     return -EIO;
 294                 pkt->stream_index =
 295                     fourxm->tracks[fourxm->selected_track].stream_index;
 296                 pkt->pts = fourxm->pts;
 297                 ret = get_buffer(&s->pb, pkt->data, size);
 298                 if (ret < 0)
 299                     av_free_packet(pkt);
 300                 else
 301                     packet_read = 1;
 302
 303                 /* maintain pts info for the benefit of the video track */
 304                 fourxm->last_chunk_was_audio = 1;
 305                 fourxm->last_audio_frame_count = size /
 306                     ((fourxm->tracks[fourxm->selected_track].bits / 8) *
 307                       fourxm->tracks[fourxm->selected_track].channels);
 308
 309             } else {
 310                 url_fseek(pb, size, SEEK_CUR);
 311             }
 312             break;
 313
 314         default:
 315             url_fseek(pb, size, SEEK_CUR);
 316             break;
 317         }
 318     }
 319     return ret;
 320 }
 321
 322 static int fourxm_read_close(AVFormatContext *s)
 323 {
 324     FourxmDemuxContext *fourxm = (FourxmDemuxContext *)s->priv_data;
 325
 326     av_free(fourxm->tracks);
 327
 328     return 0;
 329 }
 330
 331 static AVInputFormat fourxm_iformat = {
 332     "4xm",
 333     "4X Technologies format",
 334     sizeof(FourxmDemuxContext),
 335     fourxm_probe,
 336     fourxm_read_header,
 337     fourxm_read_packet,
 338     fourxm_read_close,
 339 };
 340
 341 int fourxm_init(void)
 342 {
 343     av_register_input_format(&fourxm_iformat);
 344     return 0;
 345 }