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FFmpeg/libavformat/segafilm.c

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/*
* Sega FILM Format (CPK) Demuxer
* Copyright (c) 2003 The ffmpeg Project
*
* This file is part of FFmpeg.
*
* FFmpeg is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* FFmpeg is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
/**
* @file segafilm.c
* Sega FILM (.cpk) file demuxer
* by Mike Melanson (melanson@pcisys.net)
* For more information regarding the Sega FILM file format, visit:
* http://www.pcisys.net/~melanson/codecs/
*/
#include "avformat.h"
#define FILM_TAG MKBETAG('F', 'I', 'L', 'M')
#define FDSC_TAG MKBETAG('F', 'D', 'S', 'C')
#define STAB_TAG MKBETAG('S', 'T', 'A', 'B')
#define CVID_TAG MKBETAG('c', 'v', 'i', 'd')
typedef struct {
int stream;
offset_t sample_offset;
unsigned int sample_size;
int64_t pts;
int keyframe;
} film_sample_t;
typedef struct FilmDemuxContext {
int video_stream_index;
int audio_stream_index;
unsigned int audio_type;
unsigned int audio_samplerate;
unsigned int audio_bits;
unsigned int audio_channels;
unsigned int video_type;
unsigned int sample_count;
film_sample_t *sample_table;
unsigned int current_sample;
unsigned int base_clock;
unsigned int version;
/* buffer used for interleaving stereo PCM data */
unsigned char *stereo_buffer;
int stereo_buffer_size;
} FilmDemuxContext;
static int film_probe(AVProbeData *p)
{
if (AV_RB32(&p->buf[0]) != FILM_TAG)
return 0;
return AVPROBE_SCORE_MAX;
}
static int film_read_header(AVFormatContext *s,
AVFormatParameters *ap)
{
FilmDemuxContext *film = s->priv_data;
ByteIOContext *pb = s->pb;
AVStream *st;
unsigned char scratch[256];
int i;
unsigned int data_offset;
unsigned int audio_frame_counter;
film->sample_table = NULL;
film->stereo_buffer = NULL;
film->stereo_buffer_size = 0;
/* load the main FILM header */
if (get_buffer(pb, scratch, 16) != 16)
return AVERROR(EIO);
data_offset = AV_RB32(&scratch[4]);
film->version = AV_RB32(&scratch[8]);
/* load the FDSC chunk */
if (film->version == 0) {
/* special case for Lemmings .film files; 20-byte header */
if (get_buffer(pb, scratch, 20) != 20)
return AVERROR(EIO);
/* make some assumptions about the audio parameters */
film->audio_type = CODEC_ID_PCM_S8;
film->audio_samplerate = 22050;
film->audio_channels = 1;
film->audio_bits = 8;
} else {
/* normal Saturn .cpk files; 32-byte header */
if (get_buffer(pb, scratch, 32) != 32)
return AVERROR(EIO);
film->audio_samplerate = AV_RB16(&scratch[24]);
film->audio_channels = scratch[21];
film->audio_bits = scratch[22];
if (film->audio_bits == 8)
film->audio_type = CODEC_ID_PCM_S8;
else if (film->audio_bits == 16)
film->audio_type = CODEC_ID_PCM_S16BE;
else
film->audio_type = 0;
}
if (AV_RB32(&scratch[0]) != FDSC_TAG)
return AVERROR_INVALIDDATA;
if (AV_RB32(&scratch[8]) == CVID_TAG) {
film->video_type = CODEC_ID_CINEPAK;
} else
film->video_type = 0;
/* initialize the decoder streams */
if (film->video_type) {
st = av_new_stream(s, 0);
if (!st)
return AVERROR(ENOMEM);
film->video_stream_index = st->index;
st->codec->codec_type = CODEC_TYPE_VIDEO;
st->codec->codec_id = film->video_type;
st->codec->codec_tag = 0; /* no fourcc */
st->codec->width = AV_RB32(&scratch[16]);
st->codec->height = AV_RB32(&scratch[12]);
}
if (film->audio_type) {
st = av_new_stream(s, 0);
if (!st)
return AVERROR(ENOMEM);
film->audio_stream_index = st->index;
st->codec->codec_type = CODEC_TYPE_AUDIO;
st->codec->codec_id = film->audio_type;
st->codec->codec_tag = 1;
st->codec->channels = film->audio_channels;
st->codec->bits_per_sample = film->audio_bits;
st->codec->sample_rate = film->audio_samplerate;
st->codec->bit_rate = st->codec->channels * st->codec->sample_rate *
st->codec->bits_per_sample;
st->codec->block_align = st->codec->channels *
st->codec->bits_per_sample / 8;
}
/* load the sample table */
if (get_buffer(pb, scratch, 16) != 16)
return AVERROR(EIO);
if (AV_RB32(&scratch[0]) != STAB_TAG)
return AVERROR_INVALIDDATA;
film->base_clock = AV_RB32(&scratch[8]);
film->sample_count = AV_RB32(&scratch[12]);
if(film->sample_count >= UINT_MAX / sizeof(film_sample_t))
return -1;
film->sample_table = av_malloc(film->sample_count * sizeof(film_sample_t));
for(i=0; i<s->nb_streams; i++)
av_set_pts_info(s->streams[i], 33, 1, film->base_clock);
audio_frame_counter = 0;
for (i = 0; i < film->sample_count; i++) {
/* load the next sample record and transfer it to an internal struct */
if (get_buffer(pb, scratch, 16) != 16) {
av_free(film->sample_table);
return AVERROR(EIO);
}
film->sample_table[i].sample_offset =
data_offset + AV_RB32(&scratch[0]);
film->sample_table[i].sample_size = AV_RB32(&scratch[4]);
if (AV_RB32(&scratch[8]) == 0xFFFFFFFF) {
film->sample_table[i].stream = film->audio_stream_index;
film->sample_table[i].pts = audio_frame_counter;
film->sample_table[i].pts *= film->base_clock;
film->sample_table[i].pts /= film->audio_samplerate;
audio_frame_counter += (film->sample_table[i].sample_size /
(film->audio_channels * film->audio_bits / 8));
} else {
film->sample_table[i].stream = film->video_stream_index;
film->sample_table[i].pts = AV_RB32(&scratch[8]) & 0x7FFFFFFF;
film->sample_table[i].keyframe = (scratch[8] & 0x80) ? 0 : 1;
}
}
film->current_sample = 0;
return 0;
}
static int film_read_packet(AVFormatContext *s,
AVPacket *pkt)
{
FilmDemuxContext *film = s->priv_data;
ByteIOContext *pb = s->pb;
film_sample_t *sample;
int ret = 0;
int i;
int left, right;
if (film->current_sample >= film->sample_count)
return AVERROR(EIO);
sample = &film->sample_table[film->current_sample];
/* position the stream (will probably be there anyway) */
url_fseek(pb, sample->sample_offset, SEEK_SET);
/* do a special song and dance when loading FILM Cinepak chunks */
if ((sample->stream == film->video_stream_index) &&
(film->video_type == CODEC_ID_CINEPAK)) {
pkt->pos= url_ftell(pb);
if (av_new_packet(pkt, sample->sample_size))
return AVERROR(ENOMEM);
get_buffer(pb, pkt->data, sample->sample_size);
} else if ((sample->stream == film->audio_stream_index) &&
(film->audio_channels == 2)) {
/* stereo PCM needs to be interleaved */
if (av_new_packet(pkt, sample->sample_size))
return AVERROR(ENOMEM);
/* make sure the interleave buffer is large enough */
if (sample->sample_size > film->stereo_buffer_size) {
av_free(film->stereo_buffer);
film->stereo_buffer_size = sample->sample_size;
film->stereo_buffer = av_malloc(film->stereo_buffer_size);
}
pkt->pos= url_ftell(pb);
ret = get_buffer(pb, film->stereo_buffer, sample->sample_size);
if (ret != sample->sample_size)
ret = AVERROR(EIO);
left = 0;
right = sample->sample_size / 2;
for (i = 0; i < sample->sample_size; ) {
if (film->audio_bits == 8) {
pkt->data[i++] = film->stereo_buffer[left++];
pkt->data[i++] = film->stereo_buffer[right++];
} else {
pkt->data[i++] = film->stereo_buffer[left++];
pkt->data[i++] = film->stereo_buffer[left++];
pkt->data[i++] = film->stereo_buffer[right++];
pkt->data[i++] = film->stereo_buffer[right++];
}
}
} else {
ret= av_get_packet(pb, pkt, sample->sample_size);
if (ret != sample->sample_size)
ret = AVERROR(EIO);
}
pkt->stream_index = sample->stream;
pkt->pts = sample->pts;
film->current_sample++;
return ret;
}
static int film_read_close(AVFormatContext *s)
{
FilmDemuxContext *film = s->priv_data;
av_free(film->sample_table);
av_free(film->stereo_buffer);
return 0;
}
AVInputFormat segafilm_demuxer = {
"film_cpk",
NULL_IF_CONFIG_SMALL("Sega FILM/CPK format"),
sizeof(FilmDemuxContext),
film_probe,
film_read_header,
film_read_packet,
film_read_close,
};