[FFmpeg-devel] [PATCH] avformat/scd: add demuxer
Zane van Iperen
zane at zanevaniperen.com
Wed Nov 3 16:29:30 EET 2021
Adds demuxer for Square Enux SCD files.
Based off [1] and personal investigation.
This has only been tested against Drakengard 3 (PS3) *_SCD.XXX files
(big-endian). As it is highly likely that FFXIV (PC) files are little-endian,
this demuxer is marked as experimental until this can be confirmed.
[1]: http://ffxivexplorer.fragmenterworks.com/research/scd%20files.txt
Signed-off-by: Zane van Iperen <zane at zanevaniperen.com>
---
libavformat/Makefile | 1 +
libavformat/allformats.c | 1 +
libavformat/scd.c | 377 +++++++++++++++++++++++++++++++++++++++
3 files changed, 379 insertions(+)
create mode 100644 libavformat/scd.c
diff --git a/libavformat/Makefile b/libavformat/Makefile
index 3d6c8ef8f5..725e8c0ed6 100644
--- a/libavformat/Makefile
+++ b/libavformat/Makefile
@@ -500,6 +500,7 @@ OBJS-$(CONFIG_SBC_MUXER) += rawenc.o
OBJS-$(CONFIG_SBG_DEMUXER) += sbgdec.o
OBJS-$(CONFIG_SCC_DEMUXER) += sccdec.o subtitles.o
OBJS-$(CONFIG_SCC_MUXER) += sccenc.o subtitles.o
+OBJS-$(CONFIG_SCD_DEMUXER) += scd.o
OBJS-$(CONFIG_SDP_DEMUXER) += rtsp.o
OBJS-$(CONFIG_SDR2_DEMUXER) += sdr2.o
OBJS-$(CONFIG_SDS_DEMUXER) += sdsdec.o
diff --git a/libavformat/allformats.c b/libavformat/allformats.c
index cbfadcb639..1054ac9667 100644
--- a/libavformat/allformats.c
+++ b/libavformat/allformats.c
@@ -392,6 +392,7 @@ extern const AVOutputFormat ff_sbc_muxer;
extern const AVInputFormat ff_sbg_demuxer;
extern const AVInputFormat ff_scc_demuxer;
extern const AVOutputFormat ff_scc_muxer;
+extern const AVInputFormat ff_scd_demuxer;
extern const AVInputFormat ff_sdp_demuxer;
extern const AVInputFormat ff_sdr2_demuxer;
extern const AVInputFormat ff_sds_demuxer;
diff --git a/libavformat/scd.c b/libavformat/scd.c
new file mode 100644
index 0000000000..5bb01d2114
--- /dev/null
+++ b/libavformat/scd.c
@@ -0,0 +1,377 @@
+/*
+ * Square Enix SCD demuxer
+ * Copyright (C) 2021 Zane van Iperen (zane at 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->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->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->channels * sizeof(uint16_t));
+ pkt->duration = size / (par->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;
+ SCDTrackHeader *trk = ctx->tracks + stream_index;
+
+ if (pts != 0)
+ return AVERROR(EINVAL);
+
+ trk->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,
+};
--
2.31.1
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