libavformat/segafilm.c

   1 /*
   2  * Sega FILM Format (CPK) Demuxer
   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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  18  */
  19
  20 /**
  21  * @file segafilm.c
  22  * Sega FILM (.cpk) file demuxer
  23  * by Mike Melanson (melanson@pcisys.net)
  24  * For more information regarding the Sega FILM file format, visit:
  25  *   http://www.pcisys.net/~melanson/codecs/
  26  */
  27
  28 #include "avformat.h"
  29
  30 #define FILM_TAG MKBETAG('F', 'I', 'L', 'M')
  31 #define FDSC_TAG MKBETAG('F', 'D', 'S', 'C')
  32 #define STAB_TAG MKBETAG('S', 'T', 'A', 'B')
  33 #define CVID_TAG MKBETAG('c', 'v', 'i', 'd')
  34
  35 typedef struct {
  36   int stream;
  37   offset_t sample_offset;
  38   unsigned int sample_size;
  39   int64_t pts;
  40   int keyframe;
  41 } film_sample_t;
  42
  43 typedef struct FilmDemuxContext {
  44     int video_stream_index;
  45     int audio_stream_index;
  46
  47     unsigned int audio_type;
  48     unsigned int audio_samplerate;
  49     unsigned int audio_bits;
  50     unsigned int audio_channels;
  51
  52     unsigned int video_type;
  53     unsigned int sample_count;
  54     film_sample_t *sample_table;
  55     unsigned int current_sample;
  56
  57     unsigned int base_clock;
  58     unsigned int version;
  59     int cvid_extra_bytes;  /* the number of bytes thrown into the Cinepak
  60                             * chunk header to throw off decoders */
  61
  62     /* buffer used for interleaving stereo PCM data */
  63     unsigned char *stereo_buffer;
  64     int stereo_buffer_size;
  65 } FilmDemuxContext;
  66
  67 static int film_probe(AVProbeData *p)
  68 {
  69     if (p->buf_size < 4)
  70         return 0;
  71
  72     if (BE_32(&p->buf[0]) != FILM_TAG)
  73         return 0;
  74
  75     return AVPROBE_SCORE_MAX;
  76 }
  77
  78 static int film_read_header(AVFormatContext *s,
  79                             AVFormatParameters *ap)
  80 {
  81     FilmDemuxContext *film = (FilmDemuxContext *)s->priv_data;
  82     ByteIOContext *pb = &s->pb;
  83     AVStream *st;
  84     unsigned char scratch[256];
  85     int i;
  86     unsigned int data_offset;
  87     unsigned int audio_frame_counter;
  88
  89     film->sample_table = NULL;
  90     film->stereo_buffer = NULL;
  91     film->stereo_buffer_size = 0;
  92
  93     /* load the main FILM header */
  94     if (get_buffer(pb, scratch, 16) != 16)
  95         return AVERROR_IO;
  96     data_offset = BE_32(&scratch[4]);
  97     film->version = BE_32(&scratch[8]);
  98
  99     /* load the FDSC chunk */
 100     if (film->version == 0) {
 101         /* special case for Lemmings .film files; 20-byte header */
 102         if (get_buffer(pb, scratch, 20) != 20)
 103             return AVERROR_IO;
 104         /* make some assumptions about the audio parameters */
 105         film->audio_type = CODEC_ID_PCM_S8;
 106         film->audio_samplerate = 22050;
 107         film->audio_channels = 1;
 108         film->audio_bits = 8;
 109     } else {
 110         /* normal Saturn .cpk files; 32-byte header */
 111         if (get_buffer(pb, scratch, 32) != 32)
 112             return AVERROR_IO;
 113         film->audio_samplerate = BE_16(&scratch[24]);;
 114         film->audio_channels = scratch[21];
 115         film->audio_bits = scratch[22];
 116         if (film->audio_bits == 8)
 117             film->audio_type = CODEC_ID_PCM_S8;
 118         else if (film->audio_bits == 16)
 119             film->audio_type = CODEC_ID_PCM_S16BE;
 120         else
 121             film->audio_type = 0;
 122     }
 123
 124     if (BE_32(&scratch[0]) != FDSC_TAG)
 125         return AVERROR_INVALIDDATA;
 126
 127     film->cvid_extra_bytes = 0;
 128     if (BE_32(&scratch[8]) == CVID_TAG) {
 129         film->video_type = CODEC_ID_CINEPAK;
 130         if (film->version)
 131             film->cvid_extra_bytes = 2;
 132         else
 133             film->cvid_extra_bytes = 6;  /* Lemmings 3DO case */
 134     } else
 135         film->video_type = 0;
 136
 137     /* initialize the decoder streams */
 138     if (film->video_type) {
 139         st = av_new_stream(s, 0);
 140         if (!st)
 141             return AVERROR_NOMEM;
 142         film->video_stream_index = st->index;
 143         st->codec->codec_type = CODEC_TYPE_VIDEO;
 144         st->codec->codec_id = film->video_type;
 145         st->codec->codec_tag = 0;  /* no fourcc */
 146         st->codec->width = BE_32(&scratch[16]);
 147         st->codec->height = BE_32(&scratch[12]);
 148     }
 149
 150     if (film->audio_type) {
 151         st = av_new_stream(s, 0);
 152         if (!st)
 153             return AVERROR_NOMEM;
 154         film->audio_stream_index = st->index;
 155         st->codec->codec_type = CODEC_TYPE_AUDIO;
 156         st->codec->codec_id = film->audio_type;
 157         st->codec->codec_tag = 1;
 158         st->codec->channels = film->audio_channels;
 159         st->codec->bits_per_sample = film->audio_bits;
 160         st->codec->sample_rate = film->audio_samplerate;
 161         st->codec->bit_rate = st->codec->channels * st->codec->sample_rate *
 162             st->codec->bits_per_sample;
 163         st->codec->block_align = st->codec->channels *
 164             st->codec->bits_per_sample / 8;
 165     }
 166
 167     /* load the sample table */
 168     if (get_buffer(pb, scratch, 16) != 16)
 169         return AVERROR_IO;
 170     if (BE_32(&scratch[0]) != STAB_TAG)
 171         return AVERROR_INVALIDDATA;
 172     film->base_clock = BE_32(&scratch[8]);
 173     film->sample_count = BE_32(&scratch[12]);
 174     if(film->sample_count >= UINT_MAX / sizeof(film_sample_t))
 175         return -1;
 176     film->sample_table = av_malloc(film->sample_count * sizeof(film_sample_t));
 177
 178     for(i=0; i<s->nb_streams; i++)
 179         av_set_pts_info(s->streams[i], 33, 1, film->base_clock);
 180
 181     audio_frame_counter = 0;
 182     for (i = 0; i < film->sample_count; i++) {
 183         /* load the next sample record and transfer it to an internal struct */
 184         if (get_buffer(pb, scratch, 16) != 16) {
 185             av_free(film->sample_table);
 186             return AVERROR_IO;
 187         }
 188         film->sample_table[i].sample_offset =
 189             data_offset + BE_32(&scratch[0]);
 190         film->sample_table[i].sample_size = BE_32(&scratch[4]);
 191         if (BE_32(&scratch[8]) == 0xFFFFFFFF) {
 192             film->sample_table[i].stream = film->audio_stream_index;
 193             film->sample_table[i].pts = audio_frame_counter;
 194             film->sample_table[i].pts *= film->base_clock;
 195             film->sample_table[i].pts /= film->audio_samplerate;
 196
 197             audio_frame_counter += (film->sample_table[i].sample_size /
 198                 (film->audio_channels * film->audio_bits / 8));
 199         } else {
 200             film->sample_table[i].stream = film->video_stream_index;
 201             film->sample_table[i].pts = BE_32(&scratch[8]) & 0x7FFFFFFF;
 202             film->sample_table[i].keyframe = (scratch[8] & 0x80) ? 0 : 1;
 203         }
 204     }
 205
 206     film->current_sample = 0;
 207
 208     return 0;
 209 }
 210
 211 static int film_read_packet(AVFormatContext *s,
 212                             AVPacket *pkt)
 213 {
 214     FilmDemuxContext *film = (FilmDemuxContext *)s->priv_data;
 215     ByteIOContext *pb = &s->pb;
 216     film_sample_t *sample;
 217     int ret = 0;
 218     int i;
 219     int left, right;
 220
 221     if (film->current_sample >= film->sample_count)
 222         return AVERROR_IO;
 223
 224     sample = &film->sample_table[film->current_sample];
 225
 226     /* position the stream (will probably be there anyway) */
 227     url_fseek(pb, sample->sample_offset, SEEK_SET);
 228
 229     /* do a special song and dance when loading FILM Cinepak chunks */
 230     if ((sample->stream == film->video_stream_index) &&
 231         (film->video_type == CODEC_ID_CINEPAK)) {
 232         if (av_new_packet(pkt, sample->sample_size - film->cvid_extra_bytes))
 233             return AVERROR_NOMEM;
 234         if(pkt->size < 10)
 235             return -1;
 236         pkt->pos= url_ftell(pb);
 237         ret = get_buffer(pb, pkt->data, 10);
 238         /* skip the non-spec CVID bytes */
 239         url_fseek(pb, film->cvid_extra_bytes, SEEK_CUR);
 240         ret += get_buffer(pb, pkt->data + 10,
 241             sample->sample_size - 10 - film->cvid_extra_bytes);
 242         if (ret != sample->sample_size - film->cvid_extra_bytes)
 243             ret = AVERROR_IO;
 244     } else if ((sample->stream == film->audio_stream_index) &&
 245         (film->audio_channels == 2)) {
 246         /* stereo PCM needs to be interleaved */
 247
 248         if (av_new_packet(pkt, sample->sample_size))
 249             return AVERROR_NOMEM;
 250
 251         /* make sure the interleave buffer is large enough */
 252         if (sample->sample_size > film->stereo_buffer_size) {
 253             av_free(film->stereo_buffer);
 254             film->stereo_buffer_size = sample->sample_size;
 255             film->stereo_buffer = av_malloc(film->stereo_buffer_size);
 256         }
 257
 258         pkt->pos= url_ftell(pb);
 259         ret = get_buffer(pb, film->stereo_buffer, sample->sample_size);
 260         if (ret != sample->sample_size)
 261             ret = AVERROR_IO;
 262
 263         left = 0;
 264         right = sample->sample_size / 2;
 265         for (i = 0; i < sample->sample_size; ) {
 266             if (film->audio_bits == 8) {
 267                 pkt->data[i++] = film->stereo_buffer[left++];
 268                 pkt->data[i++] = film->stereo_buffer[right++];
 269             } else {
 270                 pkt->data[i++] = film->stereo_buffer[left++];
 271                 pkt->data[i++] = film->stereo_buffer[left++];
 272                 pkt->data[i++] = film->stereo_buffer[right++];
 273                 pkt->data[i++] = film->stereo_buffer[right++];
 274             }
 275         }
 276     } else {
 277         ret= av_get_packet(pb, pkt, sample->sample_size);
 278         if (ret != sample->sample_size)
 279             ret = AVERROR_IO;
 280     }
 281
 282     pkt->stream_index = sample->stream;
 283     pkt->pts = sample->pts;
 284
 285     film->current_sample++;
 286
 287     return ret;
 288 }
 289
 290 static int film_read_close(AVFormatContext *s)
 291 {
 292     FilmDemuxContext *film = (FilmDemuxContext *)s->priv_data;
 293
 294     av_free(film->sample_table);
 295     av_free(film->stereo_buffer);
 296
 297     return 0;
 298 }
 299
 300 AVInputFormat segafilm_demuxer = {
 301     "film_cpk",
 302     "Sega FILM/CPK format",
 303     sizeof(FilmDemuxContext),
 304     film_probe,
 305     film_read_header,
 306     film_read_packet,
 307     film_read_close,
 308 };