libavformat/segafilm.c

   1 /*
   2  * Sega FILM Format (CPK) Demuxer
   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 segafilm.c
  24  * Sega FILM (.cpk) file demuxer
  25  * by Mike Melanson (melanson@pcisys.net)
  26  * For more information regarding the Sega FILM file format, visit:
  27  *   http://www.pcisys.net/~melanson/codecs/
  28  */
  29
  30 #include "avformat.h"
  31
  32 #define FILM_TAG MKBETAG('F', 'I', 'L', 'M')
  33 #define FDSC_TAG MKBETAG('F', 'D', 'S', 'C')
  34 #define STAB_TAG MKBETAG('S', 'T', 'A', 'B')
  35 #define CVID_TAG MKBETAG('c', 'v', 'i', 'd')
  36
  37 typedef struct {
  38   int stream;
  39   offset_t sample_offset;
  40   unsigned int sample_size;
  41   int64_t pts;
  42   int keyframe;
  43 } film_sample_t;
  44
  45 typedef struct FilmDemuxContext {
  46     int video_stream_index;
  47     int audio_stream_index;
  48
  49     unsigned int audio_type;
  50     unsigned int audio_samplerate;
  51     unsigned int audio_bits;
  52     unsigned int audio_channels;
  53
  54     unsigned int video_type;
  55     unsigned int sample_count;
  56     film_sample_t *sample_table;
  57     unsigned int current_sample;
  58
  59     unsigned int base_clock;
  60     unsigned int version;
  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 (AV_RB32(&p->buf[0]) != FILM_TAG)
  70         return 0;
  71
  72     return AVPROBE_SCORE_MAX;
  73 }
  74
  75 static int film_read_header(AVFormatContext *s,
  76                             AVFormatParameters *ap)
  77 {
  78     FilmDemuxContext *film = s->priv_data;
  79     ByteIOContext *pb = s->pb;
  80     AVStream *st;
  81     unsigned char scratch[256];
  82     int i;
  83     unsigned int data_offset;
  84     unsigned int audio_frame_counter;
  85
  86     film->sample_table = NULL;
  87     film->stereo_buffer = NULL;
  88     film->stereo_buffer_size = 0;
  89
  90     /* load the main FILM header */
  91     if (get_buffer(pb, scratch, 16) != 16)
  92         return AVERROR(EIO);
  93     data_offset = AV_RB32(&scratch[4]);
  94     film->version = AV_RB32(&scratch[8]);
  95
  96     /* load the FDSC chunk */
  97     if (film->version == 0) {
  98         /* special case for Lemmings .film files; 20-byte header */
  99         if (get_buffer(pb, scratch, 20) != 20)
 100             return AVERROR(EIO);
 101         /* make some assumptions about the audio parameters */
 102         film->audio_type = CODEC_ID_PCM_S8;
 103         film->audio_samplerate = 22050;
 104         film->audio_channels = 1;
 105         film->audio_bits = 8;
 106     } else {
 107         /* normal Saturn .cpk files; 32-byte header */
 108         if (get_buffer(pb, scratch, 32) != 32)
 109             return AVERROR(EIO);
 110         film->audio_samplerate = AV_RB16(&scratch[24]);
 111         film->audio_channels = scratch[21];
 112         film->audio_bits = scratch[22];
 113         if (film->audio_bits == 8)
 114             film->audio_type = CODEC_ID_PCM_S8;
 115         else if (film->audio_bits == 16)
 116             film->audio_type = CODEC_ID_PCM_S16BE;
 117         else
 118             film->audio_type = 0;
 119     }
 120
 121     if (AV_RB32(&scratch[0]) != FDSC_TAG)
 122         return AVERROR_INVALIDDATA;
 123
 124     if (AV_RB32(&scratch[8]) == CVID_TAG) {
 125         film->video_type = CODEC_ID_CINEPAK;
 126     } else
 127         film->video_type = 0;
 128
 129     /* initialize the decoder streams */
 130     if (film->video_type) {
 131         st = av_new_stream(s, 0);
 132         if (!st)
 133             return AVERROR(ENOMEM);
 134         film->video_stream_index = st->index;
 135         st->codec->codec_type = CODEC_TYPE_VIDEO;
 136         st->codec->codec_id = film->video_type;
 137         st->codec->codec_tag = 0;  /* no fourcc */
 138         st->codec->width = AV_RB32(&scratch[16]);
 139         st->codec->height = AV_RB32(&scratch[12]);
 140     }
 141
 142     if (film->audio_type) {
 143         st = av_new_stream(s, 0);
 144         if (!st)
 145             return AVERROR(ENOMEM);
 146         film->audio_stream_index = st->index;
 147         st->codec->codec_type = CODEC_TYPE_AUDIO;
 148         st->codec->codec_id = film->audio_type;
 149         st->codec->codec_tag = 1;
 150         st->codec->channels = film->audio_channels;
 151         st->codec->bits_per_sample = film->audio_bits;
 152         st->codec->sample_rate = film->audio_samplerate;
 153         st->codec->bit_rate = st->codec->channels * st->codec->sample_rate *
 154             st->codec->bits_per_sample;
 155         st->codec->block_align = st->codec->channels *
 156             st->codec->bits_per_sample / 8;
 157     }
 158
 159     /* load the sample table */
 160     if (get_buffer(pb, scratch, 16) != 16)
 161         return AVERROR(EIO);
 162     if (AV_RB32(&scratch[0]) != STAB_TAG)
 163         return AVERROR_INVALIDDATA;
 164     film->base_clock = AV_RB32(&scratch[8]);
 165     film->sample_count = AV_RB32(&scratch[12]);
 166     if(film->sample_count >= UINT_MAX / sizeof(film_sample_t))
 167         return -1;
 168     film->sample_table = av_malloc(film->sample_count * sizeof(film_sample_t));
 169
 170     for(i=0; i<s->nb_streams; i++)
 171         av_set_pts_info(s->streams[i], 33, 1, film->base_clock);
 172
 173     audio_frame_counter = 0;
 174     for (i = 0; i < film->sample_count; i++) {
 175         /* load the next sample record and transfer it to an internal struct */
 176         if (get_buffer(pb, scratch, 16) != 16) {
 177             av_free(film->sample_table);
 178             return AVERROR(EIO);
 179         }
 180         film->sample_table[i].sample_offset =
 181             data_offset + AV_RB32(&scratch[0]);
 182         film->sample_table[i].sample_size = AV_RB32(&scratch[4]);
 183         if (AV_RB32(&scratch[8]) == 0xFFFFFFFF) {
 184             film->sample_table[i].stream = film->audio_stream_index;
 185             film->sample_table[i].pts = audio_frame_counter;
 186             film->sample_table[i].pts *= film->base_clock;
 187             film->sample_table[i].pts /= film->audio_samplerate;
 188
 189             audio_frame_counter += (film->sample_table[i].sample_size /
 190                 (film->audio_channels * film->audio_bits / 8));
 191         } else {
 192             film->sample_table[i].stream = film->video_stream_index;
 193             film->sample_table[i].pts = AV_RB32(&scratch[8]) & 0x7FFFFFFF;
 194             film->sample_table[i].keyframe = (scratch[8] & 0x80) ? 0 : 1;
 195         }
 196     }
 197
 198     film->current_sample = 0;
 199
 200     return 0;
 201 }
 202
 203 static int film_read_packet(AVFormatContext *s,
 204                             AVPacket *pkt)
 205 {
 206     FilmDemuxContext *film = s->priv_data;
 207     ByteIOContext *pb = s->pb;
 208     film_sample_t *sample;
 209     int ret = 0;
 210     int i;
 211     int left, right;
 212
 213     if (film->current_sample >= film->sample_count)
 214         return AVERROR(EIO);
 215
 216     sample = &film->sample_table[film->current_sample];
 217
 218     /* position the stream (will probably be there anyway) */
 219     url_fseek(pb, sample->sample_offset, SEEK_SET);
 220
 221     /* do a special song and dance when loading FILM Cinepak chunks */
 222     if ((sample->stream == film->video_stream_index) &&
 223         (film->video_type == CODEC_ID_CINEPAK)) {
 224         pkt->pos= url_ftell(pb);
 225         if (av_new_packet(pkt, sample->sample_size))
 226             return AVERROR(ENOMEM);
 227         get_buffer(pb, pkt->data, sample->sample_size);
 228     } else if ((sample->stream == film->audio_stream_index) &&
 229         (film->audio_channels == 2)) {
 230         /* stereo PCM needs to be interleaved */
 231
 232         if (av_new_packet(pkt, sample->sample_size))
 233             return AVERROR(ENOMEM);
 234
 235         /* make sure the interleave buffer is large enough */
 236         if (sample->sample_size > film->stereo_buffer_size) {
 237             av_free(film->stereo_buffer);
 238             film->stereo_buffer_size = sample->sample_size;
 239             film->stereo_buffer = av_malloc(film->stereo_buffer_size);
 240         }
 241
 242         pkt->pos= url_ftell(pb);
 243         ret = get_buffer(pb, film->stereo_buffer, sample->sample_size);
 244         if (ret != sample->sample_size)
 245             ret = AVERROR(EIO);
 246
 247         left = 0;
 248         right = sample->sample_size / 2;
 249         for (i = 0; i < sample->sample_size; ) {
 250             if (film->audio_bits == 8) {
 251                 pkt->data[i++] = film->stereo_buffer[left++];
 252                 pkt->data[i++] = film->stereo_buffer[right++];
 253             } else {
 254                 pkt->data[i++] = film->stereo_buffer[left++];
 255                 pkt->data[i++] = film->stereo_buffer[left++];
 256                 pkt->data[i++] = film->stereo_buffer[right++];
 257                 pkt->data[i++] = film->stereo_buffer[right++];
 258             }
 259         }
 260     } else {
 261         ret= av_get_packet(pb, pkt, sample->sample_size);
 262         if (ret != sample->sample_size)
 263             ret = AVERROR(EIO);
 264     }
 265
 266     pkt->stream_index = sample->stream;
 267     pkt->pts = sample->pts;
 268
 269     film->current_sample++;
 270
 271     return ret;
 272 }
 273
 274 static int film_read_close(AVFormatContext *s)
 275 {
 276     FilmDemuxContext *film = s->priv_data;
 277
 278     av_free(film->sample_table);
 279     av_free(film->stereo_buffer);
 280
 281     return 0;
 282 }
 283
 284 AVInputFormat segafilm_demuxer = {
 285     "film_cpk",
 286     NULL_IF_CONFIG_SMALL("Sega FILM/CPK format"),
 287     sizeof(FilmDemuxContext),
 288     film_probe,
 289     film_read_header,
 290     film_read_packet,
 291     film_read_close,
 292 };