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libavformat/segafilm.c

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00001 /*
00002  * Sega FILM Format (CPK) Demuxer
00003  * Copyright (c) 2003 The ffmpeg Project
00004  *
00005  * This file is part of FFmpeg.
00006  *
00007  * FFmpeg is free software; you can redistribute it and/or
00008  * modify it under the terms of the GNU Lesser General Public
00009  * License as published by the Free Software Foundation; either
00010  * version 2.1 of the License, or (at your option) any later version.
00011  *
00012  * FFmpeg is distributed in the hope that it will be useful,
00013  * but WITHOUT ANY WARRANTY; without even the implied warranty of
00014  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
00015  * Lesser General Public License for more details.
00016  *
00017  * You should have received a copy of the GNU Lesser General Public
00018  * License along with FFmpeg; if not, write to the Free Software
00019  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
00020  */
00021 
00030 #include "libavutil/intreadwrite.h"
00031 #include "avformat.h"
00032 
00033 #define FILM_TAG MKBETAG('F', 'I', 'L', 'M')
00034 #define FDSC_TAG MKBETAG('F', 'D', 'S', 'C')
00035 #define STAB_TAG MKBETAG('S', 'T', 'A', 'B')
00036 #define CVID_TAG MKBETAG('c', 'v', 'i', 'd')
00037 
00038 typedef struct {
00039   int stream;
00040   int64_t sample_offset;
00041   unsigned int sample_size;
00042   int64_t pts;
00043   int keyframe;
00044 } film_sample;
00045 
00046 typedef struct FilmDemuxContext {
00047     int video_stream_index;
00048     int audio_stream_index;
00049 
00050     enum CodecID audio_type;
00051     unsigned int audio_samplerate;
00052     unsigned int audio_bits;
00053     unsigned int audio_channels;
00054 
00055     enum CodecID video_type;
00056     unsigned int sample_count;
00057     film_sample *sample_table;
00058     unsigned int current_sample;
00059 
00060     unsigned int base_clock;
00061     unsigned int version;
00062 
00063     /* buffer used for interleaving stereo PCM data */
00064     unsigned char *stereo_buffer;
00065     int stereo_buffer_size;
00066 } FilmDemuxContext;
00067 
00068 static int film_probe(AVProbeData *p)
00069 {
00070     if (AV_RB32(&p->buf[0]) != FILM_TAG)
00071         return 0;
00072 
00073     return AVPROBE_SCORE_MAX;
00074 }
00075 
00076 static int film_read_header(AVFormatContext *s,
00077                             AVFormatParameters *ap)
00078 {
00079     FilmDemuxContext *film = s->priv_data;
00080     AVIOContext *pb = s->pb;
00081     AVStream *st;
00082     unsigned char scratch[256];
00083     int i;
00084     unsigned int data_offset;
00085     unsigned int audio_frame_counter;
00086 
00087     film->sample_table = NULL;
00088     film->stereo_buffer = NULL;
00089     film->stereo_buffer_size = 0;
00090 
00091     /* load the main FILM header */
00092     if (avio_read(pb, scratch, 16) != 16)
00093         return AVERROR(EIO);
00094     data_offset = AV_RB32(&scratch[4]);
00095     film->version = AV_RB32(&scratch[8]);
00096 
00097     /* load the FDSC chunk */
00098     if (film->version == 0) {
00099         /* special case for Lemmings .film files; 20-byte header */
00100         if (avio_read(pb, scratch, 20) != 20)
00101             return AVERROR(EIO);
00102         /* make some assumptions about the audio parameters */
00103         film->audio_type = CODEC_ID_PCM_S8;
00104         film->audio_samplerate = 22050;
00105         film->audio_channels = 1;
00106         film->audio_bits = 8;
00107     } else {
00108         /* normal Saturn .cpk files; 32-byte header */
00109         if (avio_read(pb, scratch, 32) != 32)
00110             return AVERROR(EIO);
00111         film->audio_samplerate = AV_RB16(&scratch[24]);
00112         film->audio_channels = scratch[21];
00113         film->audio_bits = scratch[22];
00114         if (scratch[23] == 2)
00115             film->audio_type = CODEC_ID_ADPCM_ADX;
00116         else if (film->audio_channels > 0) {
00117             if (film->audio_bits == 8)
00118                 film->audio_type = CODEC_ID_PCM_S8;
00119             else if (film->audio_bits == 16)
00120                 film->audio_type = CODEC_ID_PCM_S16BE;
00121             else
00122                 film->audio_type = CODEC_ID_NONE;
00123         } else
00124             film->audio_type = CODEC_ID_NONE;
00125     }
00126 
00127     if (AV_RB32(&scratch[0]) != FDSC_TAG)
00128         return AVERROR_INVALIDDATA;
00129 
00130     if (AV_RB32(&scratch[8]) == CVID_TAG) {
00131         film->video_type = CODEC_ID_CINEPAK;
00132     } else
00133         film->video_type = CODEC_ID_NONE;
00134 
00135     /* initialize the decoder streams */
00136     if (film->video_type) {
00137         st = av_new_stream(s, 0);
00138         if (!st)
00139             return AVERROR(ENOMEM);
00140         film->video_stream_index = st->index;
00141         st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
00142         st->codec->codec_id = film->video_type;
00143         st->codec->codec_tag = 0;  /* no fourcc */
00144         st->codec->width = AV_RB32(&scratch[16]);
00145         st->codec->height = AV_RB32(&scratch[12]);
00146     }
00147 
00148     if (film->audio_type) {
00149         st = av_new_stream(s, 0);
00150         if (!st)
00151             return AVERROR(ENOMEM);
00152         film->audio_stream_index = st->index;
00153         st->codec->codec_type = AVMEDIA_TYPE_AUDIO;
00154         st->codec->codec_id = film->audio_type;
00155         st->codec->codec_tag = 1;
00156         st->codec->channels = film->audio_channels;
00157         st->codec->bits_per_coded_sample = film->audio_bits;
00158         st->codec->sample_rate = film->audio_samplerate;
00159         st->codec->bit_rate = st->codec->channels * st->codec->sample_rate *
00160             st->codec->bits_per_coded_sample;
00161         st->codec->block_align = st->codec->channels *
00162             st->codec->bits_per_coded_sample / 8;
00163     }
00164 
00165     /* load the sample table */
00166     if (avio_read(pb, scratch, 16) != 16)
00167         return AVERROR(EIO);
00168     if (AV_RB32(&scratch[0]) != STAB_TAG)
00169         return AVERROR_INVALIDDATA;
00170     film->base_clock = AV_RB32(&scratch[8]);
00171     film->sample_count = AV_RB32(&scratch[12]);
00172     if(film->sample_count >= UINT_MAX / sizeof(film_sample))
00173         return -1;
00174     film->sample_table = av_malloc(film->sample_count * sizeof(film_sample));
00175     if (!film->sample_table)
00176         return AVERROR(ENOMEM);
00177 
00178     for(i=0; i<s->nb_streams; i++)
00179         av_set_pts_info(s->streams[i], 33, 1, film->base_clock);
00180 
00181     audio_frame_counter = 0;
00182     for (i = 0; i < film->sample_count; i++) {
00183         /* load the next sample record and transfer it to an internal struct */
00184         if (avio_read(pb, scratch, 16) != 16) {
00185             av_free(film->sample_table);
00186             return AVERROR(EIO);
00187         }
00188         film->sample_table[i].sample_offset =
00189             data_offset + AV_RB32(&scratch[0]);
00190         film->sample_table[i].sample_size = AV_RB32(&scratch[4]);
00191         if (AV_RB32(&scratch[8]) == 0xFFFFFFFF) {
00192             film->sample_table[i].stream = film->audio_stream_index;
00193             film->sample_table[i].pts = audio_frame_counter;
00194             film->sample_table[i].pts *= film->base_clock;
00195             film->sample_table[i].pts /= film->audio_samplerate;
00196 
00197             if (film->audio_type == CODEC_ID_ADPCM_ADX)
00198                 audio_frame_counter += (film->sample_table[i].sample_size * 32 /
00199                     (18 * film->audio_channels));
00200             else if (film->audio_type != CODEC_ID_NONE)
00201                 audio_frame_counter += (film->sample_table[i].sample_size /
00202                     (film->audio_channels * film->audio_bits / 8));
00203         } else {
00204             film->sample_table[i].stream = film->video_stream_index;
00205             film->sample_table[i].pts = AV_RB32(&scratch[8]) & 0x7FFFFFFF;
00206             film->sample_table[i].keyframe = (scratch[8] & 0x80) ? 0 : 1;
00207         }
00208     }
00209 
00210     film->current_sample = 0;
00211 
00212     return 0;
00213 }
00214 
00215 static int film_read_packet(AVFormatContext *s,
00216                             AVPacket *pkt)
00217 {
00218     FilmDemuxContext *film = s->priv_data;
00219     AVIOContext *pb = s->pb;
00220     film_sample *sample;
00221     int ret = 0;
00222     int i;
00223     int left, right;
00224 
00225     if (film->current_sample >= film->sample_count)
00226         return AVERROR(EIO);
00227 
00228     sample = &film->sample_table[film->current_sample];
00229 
00230     /* position the stream (will probably be there anyway) */
00231     avio_seek(pb, sample->sample_offset, SEEK_SET);
00232 
00233     /* do a special song and dance when loading FILM Cinepak chunks */
00234     if ((sample->stream == film->video_stream_index) &&
00235         (film->video_type == CODEC_ID_CINEPAK)) {
00236         pkt->pos= avio_tell(pb);
00237         if (av_new_packet(pkt, sample->sample_size))
00238             return AVERROR(ENOMEM);
00239         avio_read(pb, pkt->data, sample->sample_size);
00240     } else if ((sample->stream == film->audio_stream_index) &&
00241         (film->audio_channels == 2)) {
00242         /* stereo PCM needs to be interleaved */
00243 
00244         if (av_new_packet(pkt, sample->sample_size))
00245             return AVERROR(ENOMEM);
00246 
00247         /* make sure the interleave buffer is large enough */
00248         if (sample->sample_size > film->stereo_buffer_size) {
00249             av_free(film->stereo_buffer);
00250             film->stereo_buffer_size = sample->sample_size;
00251             film->stereo_buffer = av_malloc(film->stereo_buffer_size);
00252             if (!film->stereo_buffer) {
00253                 film->stereo_buffer_size = 0;
00254                 return AVERROR(ENOMEM);
00255             }
00256         }
00257 
00258         pkt->pos= avio_tell(pb);
00259         ret = avio_read(pb, film->stereo_buffer, sample->sample_size);
00260         if (ret != sample->sample_size)
00261             ret = AVERROR(EIO);
00262 
00263         left = 0;
00264         right = sample->sample_size / 2;
00265         for (i = 0; i < sample->sample_size; ) {
00266             if (film->audio_bits == 8) {
00267                 pkt->data[i++] = film->stereo_buffer[left++];
00268                 pkt->data[i++] = film->stereo_buffer[right++];
00269             } else {
00270                 pkt->data[i++] = film->stereo_buffer[left++];
00271                 pkt->data[i++] = film->stereo_buffer[left++];
00272                 pkt->data[i++] = film->stereo_buffer[right++];
00273                 pkt->data[i++] = film->stereo_buffer[right++];
00274             }
00275         }
00276     } else {
00277         ret= av_get_packet(pb, pkt, sample->sample_size);
00278         if (ret != sample->sample_size)
00279             ret = AVERROR(EIO);
00280     }
00281 
00282     pkt->stream_index = sample->stream;
00283     pkt->pts = sample->pts;
00284 
00285     film->current_sample++;
00286 
00287     return ret;
00288 }
00289 
00290 static int film_read_close(AVFormatContext *s)
00291 {
00292     FilmDemuxContext *film = s->priv_data;
00293 
00294     av_free(film->sample_table);
00295     av_free(film->stereo_buffer);
00296 
00297     return 0;
00298 }
00299 
00300 AVInputFormat ff_segafilm_demuxer = {
00301     "film_cpk",
00302     NULL_IF_CONFIG_SMALL("Sega FILM/CPK format"),
00303     sizeof(FilmDemuxContext),
00304     film_probe,
00305     film_read_header,
00306     film_read_packet,
00307     film_read_close,
00308 };

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