ffmpeg/libavformat/segafilm.c
Anton Khirnov 9200514ad8 lavf: replace AVStream.codec with AVStream.codecpar
Currently, AVStream contains an embedded AVCodecContext instance, which
is used by demuxers to export stream parameters to the caller and by
muxers to receive stream parameters from the caller. It is also used
internally as the codec context that is passed to parsers.

In addition, it is also widely used by the callers as the decoding (when
demuxer) or encoding (when muxing) context, though this has been
officially discouraged since Libav 11.

There are multiple important problems with this approach:
    - the fields in AVCodecContext are in general one of
        * stream parameters
        * codec options
        * codec state
      However, it's not clear which ones are which. It is consequently
      unclear which fields are a demuxer allowed to set or a muxer allowed to
      read. This leads to erratic behaviour depending on whether decoding or
      encoding is being performed or not (and whether it uses the AVStream
      embedded codec context).
    - various synchronization issues arising from the fact that the same
      context is used by several different APIs (muxers/demuxers,
      parsers, bitstream filters and encoders/decoders) simultaneously, with
      there being no clear rules for who can modify what and the different
      processes being typically delayed with respect to each other.
    - avformat_find_stream_info() making it necessary to support opening
      and closing a single codec context multiple times, thus
      complicating the semantics of freeing various allocated objects in the
      codec context.

Those problems are resolved by replacing the AVStream embedded codec
context with a newly added AVCodecParameters instance, which stores only
the stream parameters exported by the demuxers or read by the muxers.
2016-02-23 17:01:58 +01:00

323 lines
10 KiB
C

/*
* Sega FILM Format (CPK) Demuxer
* Copyright (c) 2003 The ffmpeg Project
*
* This file is part of Libav.
*
* Libav 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.
*
* Libav 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 Libav; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
/**
* @file
* 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 "libavutil/intreadwrite.h"
#include "avformat.h"
#include "internal.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')
#define RAW_TAG MKBETAG('r', 'a', 'w', ' ')
typedef struct film_sample {
int stream;
int64_t sample_offset;
unsigned int sample_size;
int64_t pts;
int keyframe;
} film_sample;
typedef struct FilmDemuxContext {
int video_stream_index;
int audio_stream_index;
enum AVCodecID audio_type;
unsigned int audio_samplerate;
unsigned int audio_bits;
unsigned int audio_channels;
enum AVCodecID video_type;
unsigned int sample_count;
film_sample *sample_table;
unsigned int current_sample;
unsigned int base_clock;
unsigned int version;
} 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_close(AVFormatContext *s)
{
FilmDemuxContext *film = s->priv_data;
av_freep(&film->sample_table);
return 0;
}
static int film_read_header(AVFormatContext *s)
{
FilmDemuxContext *film = s->priv_data;
AVIOContext *pb = s->pb;
AVStream *st;
unsigned char scratch[256];
int i, ret;
unsigned int data_offset;
unsigned int audio_frame_counter;
unsigned int video_frame_counter;
film->sample_table = NULL;
/* load the main FILM header */
if (avio_read(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 (avio_read(pb, scratch, 20) != 20)
return AVERROR(EIO);
/* make some assumptions about the audio parameters */
film->audio_type = AV_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 (avio_read(pb, scratch, 32) != 32)
return AVERROR(EIO);
film->audio_samplerate = AV_RB16(&scratch[24]);
film->audio_channels = scratch[21];
if (!film->audio_channels || film->audio_channels > 2) {
av_log(s, AV_LOG_ERROR,
"Invalid number of channels: %d\n", film->audio_channels);
return AVERROR_INVALIDDATA;
}
film->audio_bits = scratch[22];
if (scratch[23] == 2)
film->audio_type = AV_CODEC_ID_ADPCM_ADX;
else if (film->audio_channels > 0) {
if (film->audio_bits == 8)
film->audio_type = AV_CODEC_ID_PCM_S8_PLANAR;
else if (film->audio_bits == 16)
film->audio_type = AV_CODEC_ID_PCM_S16BE_PLANAR;
else
film->audio_type = AV_CODEC_ID_NONE;
} else
film->audio_type = AV_CODEC_ID_NONE;
}
if (AV_RB32(&scratch[0]) != FDSC_TAG)
return AVERROR_INVALIDDATA;
if (AV_RB32(&scratch[8]) == CVID_TAG) {
film->video_type = AV_CODEC_ID_CINEPAK;
} else if (AV_RB32(&scratch[8]) == RAW_TAG) {
film->video_type = AV_CODEC_ID_RAWVIDEO;
} else {
film->video_type = AV_CODEC_ID_NONE;
}
/* initialize the decoder streams */
if (film->video_type) {
st = avformat_new_stream(s, NULL);
if (!st)
return AVERROR(ENOMEM);
film->video_stream_index = st->index;
st->codecpar->codec_type = AVMEDIA_TYPE_VIDEO;
st->codecpar->codec_id = film->video_type;
st->codecpar->codec_tag = 0; /* no fourcc */
st->codecpar->width = AV_RB32(&scratch[16]);
st->codecpar->height = AV_RB32(&scratch[12]);
if (film->video_type == AV_CODEC_ID_RAWVIDEO) {
if (scratch[20] == 24) {
st->codecpar->format = AV_PIX_FMT_RGB24;
} else {
av_log(s, AV_LOG_ERROR, "raw video is using unhandled %dbpp\n", scratch[20]);
return -1;
}
}
}
if (film->audio_type) {
st = avformat_new_stream(s, NULL);
if (!st)
return AVERROR(ENOMEM);
film->audio_stream_index = st->index;
st->codecpar->codec_type = AVMEDIA_TYPE_AUDIO;
st->codecpar->codec_id = film->audio_type;
st->codecpar->codec_tag = 1;
st->codecpar->channels = film->audio_channels;
st->codecpar->sample_rate = film->audio_samplerate;
if (film->audio_type == AV_CODEC_ID_ADPCM_ADX) {
st->codecpar->bits_per_coded_sample = 18 * 8 / 32;
st->codecpar->block_align = st->codecpar->channels * 18;
st->need_parsing = AVSTREAM_PARSE_FULL;
} else {
st->codecpar->bits_per_coded_sample = film->audio_bits;
st->codecpar->block_align = st->codecpar->channels *
st->codecpar->bits_per_coded_sample / 8;
}
st->codecpar->bit_rate = st->codecpar->channels * st->codecpar->sample_rate *
st->codecpar->bits_per_coded_sample;
}
/* load the sample table */
if (avio_read(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))
return -1;
film->sample_table = av_malloc(film->sample_count * sizeof(film_sample));
if (!film->sample_table)
return AVERROR(ENOMEM);
for (i = 0; i < s->nb_streams; i++) {
st = s->streams[i];
if (st->codecpar->codec_type == AVMEDIA_TYPE_VIDEO)
avpriv_set_pts_info(st, 33, 1, film->base_clock);
else
avpriv_set_pts_info(st, 64, 1, film->audio_samplerate);
}
audio_frame_counter = video_frame_counter = 0;
for (i = 0; i < film->sample_count; i++) {
/* load the next sample record and transfer it to an internal struct */
if (avio_read(pb, scratch, 16) != 16) {
ret = AVERROR(EIO);
goto fail;
}
film->sample_table[i].sample_offset =
data_offset + AV_RB32(&scratch[0]);
film->sample_table[i].sample_size = AV_RB32(&scratch[4]);
if (film->sample_table[i].sample_size > INT_MAX / 4) {
ret = AVERROR_INVALIDDATA;
goto fail;
}
if (AV_RB32(&scratch[8]) == 0xFFFFFFFF) {
film->sample_table[i].stream = film->audio_stream_index;
film->sample_table[i].pts = audio_frame_counter;
if (film->audio_type == AV_CODEC_ID_ADPCM_ADX)
audio_frame_counter += (film->sample_table[i].sample_size * 32 /
(18 * film->audio_channels));
else if (film->audio_type != AV_CODEC_ID_NONE)
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;
video_frame_counter++;
av_add_index_entry(s->streams[film->video_stream_index],
film->sample_table[i].sample_offset,
film->sample_table[i].pts,
film->sample_table[i].sample_size, 0,
film->sample_table[i].keyframe);
}
}
if (film->audio_type)
s->streams[film->audio_stream_index]->duration = audio_frame_counter;
if (film->video_type)
s->streams[film->video_stream_index]->duration = video_frame_counter;
film->current_sample = 0;
return 0;
fail:
film_read_close(s);
return ret;
}
static int film_read_packet(AVFormatContext *s,
AVPacket *pkt)
{
FilmDemuxContext *film = s->priv_data;
AVIOContext *pb = s->pb;
film_sample *sample;
int ret = 0;
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) */
avio_seek(pb, sample->sample_offset, SEEK_SET);
ret = av_get_packet(pb, pkt, sample->sample_size);
if (ret < 0)
return ret;
pkt->stream_index = sample->stream;
pkt->pts = sample->pts;
film->current_sample++;
return ret;
}
static int film_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
{
FilmDemuxContext *film = s->priv_data;
AVStream *st = s->streams[stream_index];
int64_t pos;
int ret = av_index_search_timestamp(st, timestamp, flags);
if (ret < 0)
return ret;
pos = avio_seek(s->pb, st->index_entries[ret].pos, SEEK_SET);
if (pos < 0)
return pos;
film->current_sample = ret;
return 0;
}
AVInputFormat ff_segafilm_demuxer = {
.name = "film_cpk",
.long_name = NULL_IF_CONFIG_SMALL("Sega FILM / CPK"),
.priv_data_size = sizeof(FilmDemuxContext),
.read_probe = film_probe,
.read_header = film_read_header,
.read_packet = film_read_packet,
.read_close = film_read_close,
.read_seek = film_read_seek,
};