/*
* Square Enix SCD demuxer
* Copyright (C) 2021 Zane van Iperen (zane@zanevaniperen.com)
*
* Based off documentation:
* http://ffxivexplorer.fragmenterworks.com/research/scd%20files.txt
*
* 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
*/
#include "libavutil/avstring.h"
#include "libavutil/intreadwrite.h"
#include "libavutil/internal.h"
#include "libavutil/macros.h"
#include "libavutil/avassert.h"
#include "libavformat/internal.h"
#include "avformat.h"
#define SCD_MAGIC ((uint64_t)MKBETAG('S', 'E', 'D', 'B') << 32 | \
MKBETAG('S', 'S', 'C', 'F'))
#define SCD_MIN_HEADER_SIZE 20
#define SCD_OFFSET_HEADER_SIZE 28
#define SCD_TRACK_HEADER_SIZE 32
#define SCD_TRACK_ID_PCM 0
#define SCD_TRACK_ID_OGG 6
#define SCD_TRACK_ID_MP3 7
#define SCD_TRACK_ID_MS_ADPCM 12
typedef struct SCDOffsetTable {
uint16_t count;
uint32_t offset;
uint32_t *entries;
} SCDOffsetTable;
typedef struct SCDHeader {
uint64_t magic; /* SEDBSSCF */
uint32_t version; /* Verison number. We only know about 3. */
uint16_t unk1; /* Unknown, 260 in Drakengard 3, 1024 in FFXIV. */
uint16_t header_size; /* Total size of this header. */
uint32_t file_size; /* Is often 0, just ignore it. */
SCDOffsetTable table0; /* Table 0, no idea. 56 uint32's/entry. */
SCDOffsetTable table1; /* Table 1, contains the track info. */
SCDOffsetTable table2; /* Table 2, no idea. 40 uint32's/entry. */
uint16_t unk2; /* Unknown, not a count. */
uint32_t unk3; /* Unknown, not an offset. */
uint32_t unk4; /* Unknown, offset to offset. */
} SCDHeader;
typedef struct SCDTrackHeader {
uint32_t length;
uint32_t num_channels;
uint32_t sample_rate;
uint32_t data_type;
uint32_t loop_start;
uint32_t loop_end;
uint32_t data_offset; /* Offset to data + this header. */
uint32_t aux_count;
uint32_t absolute_offset;
uint32_t bytes_read;
} SCDTrackHeader;
typedef struct SCDDemuxContext {
SCDHeader hdr;
SCDTrackHeader *tracks;
int current_track;
} SCDDemuxContext;
static int scd_probe(const AVProbeData *p)
{
if (AV_RB64(p->buf) != SCD_MAGIC)
return 0;
return AVPROBE_SCORE_MAX;
}
static int scd_read_table(AVFormatContext *s, SCDOffsetTable *table)
{
int64_t ret;
if ((ret = avio_seek(s->pb, table->offset, SEEK_SET)) < 0)
return ret;
if ((table->entries = av_calloc(table->count, sizeof(uint32_t))) == NULL)
return ret;
if ((ret = avio_read(s->pb, (unsigned char*)table->entries, table->count * sizeof(uint32_t))) < 0)
return ret;
for (size_t i = 0; i < table->count; i++)
table->entries[i] = AV_RB32(table->entries + i);
av_log(s, AV_LOG_TRACE, "Table, size = %u, offset = %u\n", table->count, table->offset);
for (size_t i = 0; i < table->count; i++)
av_log(s, AV_LOG_TRACE, " [%02zu]: %u\n", i, table->entries[i]);
return 0;
}
static int scd_read_offsets(AVFormatContext *s)
{
int64_t ret;
SCDDemuxContext *ctx = s->priv_data;
uint8_t buf[SCD_OFFSET_HEADER_SIZE];
if ((ret = avio_read(s->pb, buf, SCD_OFFSET_HEADER_SIZE)) < 0)
return ret;
ctx->hdr.table0.count = AV_RB16(buf + 0);
ctx->hdr.table1.count = AV_RB16(buf + 2);
ctx->hdr.table2.count = AV_RB16(buf + 4);
ctx->hdr.unk2 = AV_RB16(buf + 6);
ctx->hdr.table0.offset = AV_RB32(buf + 8);
ctx->hdr.table1.offset = AV_RB32(buf + 12);
ctx->hdr.table2.offset = AV_RB32(buf + 16);
ctx->hdr.unk3 = AV_RB32(buf + 20);
ctx->hdr.unk4 = AV_RB32(buf + 24);
if ((ret = scd_read_table(s, &ctx->hdr.table0)) < 0)
return ret;
if ((ret = scd_read_table(s, &ctx->hdr.table1)) < 0)
return ret;
if ((ret = scd_read_table(s, &ctx->hdr.table2)) < 0)
return ret;
return 0;
}
static int scd_read_track(AVFormatContext *s, SCDTrackHeader *track, int index)
{
int64_t ret;
uint32_t hoffset;
AVStream *st;
AVCodecParameters *par;
SCDDemuxContext *ctx = s->priv_data;
uint8_t buf[SCD_TRACK_HEADER_SIZE];
/* Mark as experimental until I find more files from more than just one game. */
if (s->strict_std_compliance > FF_COMPLIANCE_EXPERIMENTAL) {
av_log(s, AV_LOG_ERROR, "SCD demuxing is experimental, "
"add '-strict %d' if you want to use it.\n",
FF_COMPLIANCE_EXPERIMENTAL);
return AVERROR_EXPERIMENTAL;
}
hoffset = ctx->hdr.table1.entries[index];
if ((ret = avio_seek(s->pb, hoffset, SEEK_SET)) < 0)
return ret;
if ((ret = avio_read(s->pb, buf, SCD_TRACK_HEADER_SIZE)) < 0)
return ret;
track->length = AV_RB32(buf + 0);
track->num_channels = AV_RB32(buf + 4);
track->sample_rate = AV_RB32(buf + 8);
track->data_type = AV_RB32(buf + 12);
track->loop_start = AV_RB32(buf + 16);
track->loop_end = AV_RB32(buf + 20);
track->data_offset = AV_RB32(buf + 24);
track->aux_count = AV_RB32(buf + 28);
/* Sanity checks */
if (track->num_channels > 8 || track->sample_rate >= 192000 ||
track->loop_start > track->loop_end)
return AVERROR_INVALIDDATA;
track->absolute_offset = hoffset + SCD_TRACK_HEADER_SIZE + track->data_offset;
track->bytes_read = 0;
/* Not sure what to do with these, it seems to be fine to ignore them. */
if (track->aux_count != 0)
av_log(s, AV_LOG_DEBUG, "[%d] Track has %u auxillary chunk(s).\n", index, track->aux_count);
if ((st = avformat_new_stream(s, NULL)) == NULL)
return AVERROR(ENOMEM);
par = st->codecpar;
par->codec_type = AVMEDIA_TYPE_AUDIO;
par->ch_layout.nb_channels = (int)track->num_channels;
par->sample_rate = (int)track->sample_rate;
st->index = index;
st->start_time = 0;
/* TODO: Check this with other types. Drakengard 3 MP3s have 47999 instead of 48000. */
if (track->data_type == SCD_TRACK_ID_MP3)
par->sample_rate += 1;
avpriv_set_pts_info(st, 64, 1, par->sample_rate);
if (av_dict_set_int(&st->metadata, "start", track->absolute_offset, 0) < 0)
return AVERROR(ENOMEM);
if (av_dict_set_int(&st->metadata, "loop_start", track->loop_start, 0) < 0)
return AVERROR(ENOMEM);
if (av_dict_set_int(&st->metadata, "loop_end", track->loop_end, 0) < 0)
return AVERROR(ENOMEM);
switch(track->data_type) {
case SCD_TRACK_ID_PCM:
par->codec_id = AV_CODEC_ID_PCM_S16BE;
par->bits_per_coded_sample = 16;
par->block_align = par->bits_per_coded_sample * par->ch_layout.nb_channels / 8;
break;
case SCD_TRACK_ID_MP3:
par->codec_id = AV_CODEC_ID_MP3;
ffstream(st)->need_parsing = AVSTREAM_PARSE_FULL_RAW;
break;
case SCD_TRACK_ID_OGG:
case SCD_TRACK_ID_MS_ADPCM:
default:
par->codec_id = AV_CODEC_ID_NONE;
avpriv_request_sample(s, "data type %u", track->data_type);
}
return 0;
}
static int scd_read_header(AVFormatContext *s)
{
int64_t ret;
SCDDemuxContext *ctx = s->priv_data;
uint8_t buf[SCD_MIN_HEADER_SIZE];
if ((ret = avio_read(s->pb, buf, SCD_MIN_HEADER_SIZE)) < 0)
return ret;
ctx->hdr.magic = AV_RB64(buf + 0);
ctx->hdr.version = AV_RB32(buf + 8);
ctx->hdr.unk1 = AV_RB16(buf + 12);
ctx->hdr.header_size = AV_RB16(buf + 14);
ctx->hdr.file_size = AV_RB32(buf + 16);
if (ctx->hdr.magic != SCD_MAGIC)
return AVERROR_INVALIDDATA;
if (ctx->hdr.version != 3) {
avpriv_request_sample(s, "SCD version %u", ctx->hdr.version);
return AVERROR_PATCHWELCOME;
}
if (ctx->hdr.header_size < SCD_MIN_HEADER_SIZE)
return AVERROR_INVALIDDATA;
if ((ret = avio_skip(s->pb, ctx->hdr.header_size - SCD_MIN_HEADER_SIZE)) < 0)
return ret;
if ((ret = scd_read_offsets(s)) < 0)
return ret;
ctx->tracks = av_calloc(ctx->hdr.table1.count, sizeof(SCDTrackHeader));
if (ctx->tracks == NULL)
return AVERROR(ENOMEM);
for (int i = 0; i < ctx->hdr.table1.count; i++) {
if ((ret = scd_read_track(s, ctx->tracks + i, i)) < 0)
return ret;
}
if (ctx->hdr.table1.count == 0)
return 0;
if ((ret = avio_seek(s->pb, ctx->tracks[0].absolute_offset, SEEK_SET)) < 0)
return ret;
return 0;
}
static int scd_read_packet(AVFormatContext *s, AVPacket *pkt)
{
SCDDemuxContext *ctx = s->priv_data;
AVCodecParameters *par;
/* Streams aren't interleaved, round-robin them. */
for (int i = 0; i < ctx->hdr.table1.count; i++) {
int64_t ret;
int size;
SCDTrackHeader *trk;
ctx->current_track %= ctx->hdr.table1.count;
trk = ctx->tracks + ctx->current_track;
par = s->streams[ctx->current_track]->codecpar;
if (trk->bytes_read >= trk->length)
continue;
if ((ret = avio_seek(s->pb, trk->absolute_offset + trk->bytes_read, SEEK_SET)) < 0)
return ret;
switch(trk->data_type) {
case SCD_TRACK_ID_PCM:
size = par->block_align;
break;
case SCD_TRACK_ID_MP3:
default:
size = FFMIN(trk->length - trk->bytes_read, 4096);
break;
}
ret = av_get_packet(s->pb, pkt, size);
if (ret == AVERROR_EOF) {
trk->length = trk->bytes_read;
continue;
} else if (ret < 0) {
return ret;
}
if (trk->data_type == SCD_TRACK_ID_PCM) {
pkt->pts = trk->bytes_read / (par->ch_layout.nb_channels * sizeof(uint16_t));
pkt->duration = size / (par->ch_layout.nb_channels * sizeof(int16_t));
}
trk->bytes_read += ret;
pkt->flags &= ~AV_PKT_FLAG_CORRUPT;
pkt->stream_index = ctx->current_track;
ctx->current_track++;
return 0;
}
return AVERROR_EOF;
}
static int scd_seek(AVFormatContext *s, int stream_index,
int64_t pts, int flags)
{
SCDDemuxContext *ctx = s->priv_data;
if (pts != 0)
return AVERROR(EINVAL);
for(int i = 0; i < ctx->hdr.table1.count; ++i)
ctx->tracks[i].bytes_read = 0;
return 0;
}
static int scd_read_close(AVFormatContext *s)
{
SCDDemuxContext *ctx = s->priv_data;
av_freep(&ctx->hdr.table0.entries);
av_freep(&ctx->hdr.table1.entries);
av_freep(&ctx->hdr.table2.entries);
av_freep(&ctx->tracks);
return 0;
}
const AVInputFormat ff_scd_demuxer = {
.name = "scd",
.long_name = NULL_IF_CONFIG_SMALL("Square Enix SCD"),
.priv_data_size = sizeof(SCDDemuxContext),
.flags_internal = FF_FMT_INIT_CLEANUP,
.read_probe = scd_probe,
.read_header = scd_read_header,
.read_packet = scd_read_packet,
.read_seek = scd_seek,
.read_close = scd_read_close,
};