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FFmpeg/libavformat/psxstr.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

282 lines
8.9 KiB
C

/*
* Sony Playstation (PSX) STR File 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
* PSX STR file demuxer
* by Mike Melanson (melanson@pcisys.net)
* This module handles streams that have been ripped from Sony Playstation
* CD games. This demuxer can handle either raw STR files (which are just
* concatenations of raw compact disc sectors) or STR files with 0x2C-byte
* RIFF headers, followed by CD sectors.
*/
#include "libavutil/channel_layout.h"
#include "libavutil/internal.h"
#include "libavutil/intreadwrite.h"
#include "avformat.h"
#include "internal.h"
#define RIFF_TAG MKTAG('R', 'I', 'F', 'F')
#define CDXA_TAG MKTAG('C', 'D', 'X', 'A')
#define RAW_CD_SECTOR_SIZE 2352
#define RAW_CD_SECTOR_DATA_SIZE 2304
#define VIDEO_DATA_CHUNK_SIZE 0x7E0
#define VIDEO_DATA_HEADER_SIZE 0x38
#define RIFF_HEADER_SIZE 0x2C
#define CDXA_TYPE_MASK 0x0E
#define CDXA_TYPE_DATA 0x08
#define CDXA_TYPE_AUDIO 0x04
#define CDXA_TYPE_VIDEO 0x02
#define STR_MAGIC (0x80010160)
typedef struct StrChannel {
/* video parameters */
int video_stream_index;
AVPacket tmp_pkt;
/* audio parameters */
int audio_stream_index;
} StrChannel;
typedef struct StrDemuxContext {
/* a STR file can contain up to 32 channels of data */
StrChannel channels[32];
} StrDemuxContext;
static const char sync_header[12] = {0x00,0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff,0xff,0x00};
static int str_probe(AVProbeData *p)
{
uint8_t *sector= p->buf;
if (p->buf_size < RAW_CD_SECTOR_SIZE)
return 0;
if ((AV_RL32(&p->buf[0]) == RIFF_TAG) &&
(AV_RL32(&p->buf[8]) == CDXA_TAG)) {
/* RIFF header seen; skip 0x2C bytes */
sector += RIFF_HEADER_SIZE;
}
/* look for CD sync header (00, 0xFF x 10, 00) */
if (memcmp(sector,sync_header,sizeof(sync_header)))
return 0;
if(sector[0x11] >= 32)
return 0;
if( (sector[0x12] & CDXA_TYPE_MASK) != CDXA_TYPE_VIDEO
&& (sector[0x12] & CDXA_TYPE_MASK) != CDXA_TYPE_AUDIO
&& (sector[0x12] & CDXA_TYPE_MASK) != CDXA_TYPE_DATA)
return 0;
/* MPEG files (like those ripped from VCDs) can also look like this;
* only return half certainty */
return AVPROBE_SCORE_EXTENSION;
}
static int str_read_header(AVFormatContext *s)
{
AVIOContext *pb = s->pb;
StrDemuxContext *str = s->priv_data;
unsigned char sector[RAW_CD_SECTOR_SIZE];
int start;
int i;
/* skip over any RIFF header */
if (avio_read(pb, sector, RIFF_HEADER_SIZE) != RIFF_HEADER_SIZE)
return AVERROR(EIO);
if (AV_RL32(&sector[0]) == RIFF_TAG)
start = RIFF_HEADER_SIZE;
else
start = 0;
avio_seek(pb, start, SEEK_SET);
for(i=0; i<32; i++){
str->channels[i].video_stream_index=
str->channels[i].audio_stream_index= -1;
}
s->ctx_flags |= AVFMTCTX_NOHEADER;
return 0;
}
static int str_read_packet(AVFormatContext *s,
AVPacket *ret_pkt)
{
AVIOContext *pb = s->pb;
StrDemuxContext *str = s->priv_data;
unsigned char sector[RAW_CD_SECTOR_SIZE];
int channel;
AVPacket *pkt;
AVStream *st;
while (1) {
if (avio_read(pb, sector, RAW_CD_SECTOR_SIZE) != RAW_CD_SECTOR_SIZE)
return AVERROR(EIO);
channel = sector[0x11];
if (channel >= 32)
return AVERROR_INVALIDDATA;
switch (sector[0x12] & CDXA_TYPE_MASK) {
case CDXA_TYPE_DATA:
case CDXA_TYPE_VIDEO:
{
int current_sector = AV_RL16(&sector[0x1C]);
int sector_count = AV_RL16(&sector[0x1E]);
int frame_size = AV_RL32(&sector[0x24]);
if(!( frame_size>=0
&& current_sector < sector_count
&& sector_count*VIDEO_DATA_CHUNK_SIZE >=frame_size)){
av_log(s, AV_LOG_ERROR, "Invalid parameters %d %d %d\n", current_sector, sector_count, frame_size);
break;
}
if(str->channels[channel].video_stream_index < 0){
/* allocate a new AVStream */
st = avformat_new_stream(s, NULL);
if (!st)
return AVERROR(ENOMEM);
avpriv_set_pts_info(st, 64, 1, 15);
str->channels[channel].video_stream_index = st->index;
st->codecpar->codec_type = AVMEDIA_TYPE_VIDEO;
st->codecpar->codec_id = AV_CODEC_ID_MDEC;
st->codecpar->codec_tag = 0; /* no fourcc */
st->codecpar->width = AV_RL16(&sector[0x28]);
st->codecpar->height = AV_RL16(&sector[0x2A]);
}
/* if this is the first sector of the frame, allocate a pkt */
pkt = &str->channels[channel].tmp_pkt;
if(pkt->size != sector_count*VIDEO_DATA_CHUNK_SIZE){
if(pkt->data)
av_log(s, AV_LOG_ERROR, "missmatching sector_count\n");
av_packet_unref(pkt);
if (av_new_packet(pkt, sector_count*VIDEO_DATA_CHUNK_SIZE))
return AVERROR(EIO);
pkt->pos= avio_tell(pb) - RAW_CD_SECTOR_SIZE;
pkt->stream_index =
str->channels[channel].video_stream_index;
}
memcpy(pkt->data + current_sector*VIDEO_DATA_CHUNK_SIZE,
sector + VIDEO_DATA_HEADER_SIZE,
VIDEO_DATA_CHUNK_SIZE);
if (current_sector == sector_count-1) {
pkt->size= frame_size;
*ret_pkt = *pkt;
pkt->data= NULL;
pkt->size= -1;
pkt->buf = NULL;
return 0;
}
}
break;
case CDXA_TYPE_AUDIO:
if(str->channels[channel].audio_stream_index < 0){
int fmt = sector[0x13];
/* allocate a new AVStream */
st = avformat_new_stream(s, NULL);
if (!st)
return AVERROR(ENOMEM);
str->channels[channel].audio_stream_index = st->index;
st->codecpar->codec_type = AVMEDIA_TYPE_AUDIO;
st->codecpar->codec_id = AV_CODEC_ID_ADPCM_XA;
st->codecpar->codec_tag = 0; /* no fourcc */
if (fmt & 1) {
st->codecpar->channels = 2;
st->codecpar->channel_layout = AV_CH_LAYOUT_STEREO;
} else {
st->codecpar->channels = 1;
st->codecpar->channel_layout = AV_CH_LAYOUT_MONO;
}
st->codecpar->sample_rate = (fmt&4)?18900:37800;
// st->codecpar->bit_rate = 0; //FIXME;
st->codecpar->block_align = 128;
avpriv_set_pts_info(st, 64, 18 * 224 / st->codecpar->channels,
st->codecpar->sample_rate);
st->start_time = 0;
}
pkt = ret_pkt;
if (av_new_packet(pkt, 2304))
return AVERROR(EIO);
memcpy(pkt->data,sector+24,2304);
pkt->stream_index =
str->channels[channel].audio_stream_index;
pkt->duration = 1;
return 0;
default:
av_log(s, AV_LOG_WARNING, "Unknown sector type %02X\n", sector[0x12]);
/* drop the sector and move on */
break;
}
if (pb->eof_reached)
return AVERROR(EIO);
}
}
static int str_read_close(AVFormatContext *s)
{
StrDemuxContext *str = s->priv_data;
int i;
for(i=0; i<32; i++){
if(str->channels[i].tmp_pkt.data)
av_packet_unref(&str->channels[i].tmp_pkt);
}
return 0;
}
AVInputFormat ff_str_demuxer = {
.name = "psxstr",
.long_name = NULL_IF_CONFIG_SMALL("Sony Playstation STR"),
.priv_data_size = sizeof(StrDemuxContext),
.read_probe = str_probe,
.read_header = str_read_header,
.read_packet = str_read_packet,
.read_close = str_read_close,
.flags = AVFMT_NO_BYTE_SEEK,
};