[FFmpeg-devel] [PATCH] avformat: add mca demuxer
liushuyu at aosc.io
liushuyu at aosc.io
Wed Sep 2 01:57:01 EEST 2020
From: Zixing Liu <liushuyu at aosc.io>
Signed-off-by: liushuyu <liushuyu at aosc.io>
---
Changelog | 1 +
doc/general.texi | 2 +
libavformat/Makefile | 1 +
libavformat/allformats.c | 1 +
libavformat/mca.c | 240 +++++++++++++++++++++++++++++++++++++++
libavformat/version.h | 4 +-
6 files changed, 247 insertions(+), 2 deletions(-)
create mode 100644 libavformat/mca.c
diff --git a/Changelog b/Changelog
index 7467e73..ae4219f 100644
--- a/Changelog
+++ b/Changelog
@@ -15,6 +15,7 @@ version <next>:
- Argonaut Games ASF muxer
- AV1 Low overhead bitstream format demuxer
- RPZA video encoder
+- MCA demuxer
version 4.3:
diff --git a/doc/general.texi b/doc/general.texi
index d618565..fa76ed4 100644
--- a/doc/general.texi
+++ b/doc/general.texi
@@ -524,6 +524,8 @@ library:
@tab Metadata in text format.
@item MAXIS XA @tab @tab X
@tab Used in Sim City 3000; file extension .xa.
+ at item MCA @tab @tab X
+ @tab Used in some games from Capcom; file extension .mca.
@item MD Studio @tab @tab X
@item Metal Gear Solid: The Twin Snakes @tab @tab X
@item Megalux Frame @tab @tab X
diff --git a/libavformat/Makefile b/libavformat/Makefile
index cbb33fe..7f5ab21 100644
--- a/libavformat/Makefile
+++ b/libavformat/Makefile
@@ -305,6 +305,7 @@ OBJS-$(CONFIG_MATROSKA_MUXER) += matroskaenc.o matroska.o \
av1.o avc.o hevc.o \
flacenc_header.o avlanguage.o \
vorbiscomment.o wv.o
+OBJS-$(CONFIG_MCA_DEMUXER) += mca.o
OBJS-$(CONFIG_MCC_DEMUXER) += mccdec.o subtitles.o
OBJS-$(CONFIG_MD5_MUXER) += hashenc.o
OBJS-$(CONFIG_MGSTS_DEMUXER) += mgsts.o
diff --git a/libavformat/allformats.c b/libavformat/allformats.c
index 0aa9dd7..8a71de6 100644
--- a/libavformat/allformats.c
+++ b/libavformat/allformats.c
@@ -232,6 +232,7 @@ extern AVInputFormat ff_lvf_demuxer;
extern AVInputFormat ff_lxf_demuxer;
extern AVInputFormat ff_m4v_demuxer;
extern AVOutputFormat ff_m4v_muxer;
+extern AVInputFormat ff_mca_demuxer;
extern AVInputFormat ff_mcc_demuxer;
extern AVOutputFormat ff_md5_muxer;
extern AVInputFormat ff_matroska_demuxer;
diff --git a/libavformat/mca.c b/libavformat/mca.c
new file mode 100644
index 0000000..e51d3fb
--- /dev/null
+++ b/libavformat/mca.c
@@ -0,0 +1,240 @@
+/*
+ * MCA demuxer
+ * Copyright (c) 2020 Zixing Liu
+ *
+ * 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/intreadwrite.h"
+#include "libavcodec/bytestream.h"
+#include "avformat.h"
+#include "internal.h"
+
+typedef struct MCADemuxContext {
+ uint32_t block_count;
+ uint16_t block_size;
+ uint32_t coef_offset;
+ uint32_t current_block;
+ uint32_t data_start;
+ uint32_t samples_per_block;
+} MCADemuxContext;
+
+static int probe(const AVProbeData *p)
+{
+ if (AV_RL32(p->buf) == MKTAG('M', 'A', 'D', 'P') &&
+ (AV_RL16(p->buf + 4) > 0x00 || AV_RL16(p->buf + 4) <= 0xff))
+ return AVPROBE_SCORE_MAX / 3 * 2;
+ return 0;
+}
+
+static int read_header(AVFormatContext *s)
+{
+ AVStream *st;
+ MCADemuxContext *m = s->priv_data;
+ int16_t version = 0;
+ int64_t file_size = 0;
+ uint32_t header_size, data_size, data_offset, loop_start, loop_end,
+ nb_samples, nb_metadata = 0;
+ int ch;
+ int ret = AVERROR_EOF;
+
+ st = avformat_new_stream(s, NULL);
+ if (!st)
+ return AVERROR(ENOMEM);
+ st->codecpar->codec_type = AVMEDIA_TYPE_AUDIO;
+
+ // parse file headers
+ avio_skip(s->pb, 0x4); // skip the file magic
+ version = avio_rl16(s->pb); // offset 0x4
+ avio_skip(s->pb, 0x2); // padding
+ st->codecpar->channels = avio_r8(s->pb); // offset 0x8
+ avio_skip(s->pb, 0x1); // padding
+ m->block_size = avio_rl16(s->pb); // offset 0xa
+ nb_samples = avio_rl32(s->pb); // offset 0xc
+ st->codecpar->sample_rate = avio_rl32(s->pb); // offset 0x10
+ loop_start = avio_rl32(s->pb); // offset 0x14
+ loop_end = avio_rl32(s->pb); // offset 0x18
+ header_size = avio_rl32(s->pb); // offset 0x1c
+ data_size = avio_rl32(s->pb); // offset 0x20
+ avio_skip(s->pb, 0x4); // offset 0x24 (duration, float)
+ nb_metadata = avio_rl16(s->pb); // offset 0x28
+ avio_skip(s->pb, 0x2); // unknown u16 field
+
+ file_size = avio_size(s->pb);
+
+ // samples per frame = 14; frame size = 8 (2^3)
+ m->samples_per_block = (m->block_size * 14) >> 3;
+ m->block_count = nb_samples / m->samples_per_block;
+ st->duration = nb_samples;
+
+ // sanity checks
+ if (version < 0 || !st->codecpar->channels
+ || st->codecpar->sample_rate <= 0 || m->samples_per_block < 1
+ || loop_start > loop_end || m->block_count < 1)
+ return AVERROR_INVALIDDATA;
+ if (av_dict_set_int(&s->metadata, "loop_start",
+ av_rescale(loop_start, AV_TIME_BASE,
+ st->codecpar->sample_rate), 0) < 0)
+ return AVERROR(ENOMEM);
+ if (av_dict_set_int(&s->metadata, "loop_end",
+ av_rescale(loop_end, AV_TIME_BASE,
+ st->codecpar->sample_rate), 0) < 0)
+ return AVERROR(ENOMEM);
+ avpriv_set_pts_info(st, 64, 1, st->codecpar->sample_rate);
+
+ if (version <= 4) {
+ // version <= 4 needs to use the file size to calculate the offsets
+ if (file_size < 0) {
+ return AVERROR(EIO);
+ }
+ m->data_start = file_size - data_size;
+ if (version <= 3) {
+ nb_metadata = 0;
+ // header_size is not available or incorrect in older versions
+ header_size = m->data_start;
+ }
+ } else if (version == 5) {
+ // read data_start location from the header
+ data_offset = header_size - 0x30 * st->codecpar->channels - 0x4;
+ ret = avio_seek(s->pb, data_offset, SEEK_SET);
+ if (ret < 0)
+ return ret;
+ m->data_start = avio_rl32(s->pb);
+ // check if the metadata is reasonable
+ if (file_size > 0 && m->data_start + data_size > file_size) {
+ // the header is broken beyond repair
+ if (header_size + data_size > file_size) {
+ av_log(s, AV_LOG_ERROR,
+ "MCA metadata corrupted, unable to determine the data offset.\n");
+ return AVERROR_INVALIDDATA;
+ }
+ // recover the data_start information from the data size
+ av_log(s, AV_LOG_WARNING,
+ "Incorrect header size found in metadata, header size approximated from the data size\n");
+ m->data_start = file_size - data_size;
+ }
+ } else {
+ avpriv_request_sample(s, "version %d", version);
+ return AVERROR_PATCHWELCOME;
+ }
+
+ // coefficient alignment = 0x30; metadata size = 0x14
+ m->coef_offset =
+ header_size - 0x30 * st->codecpar->channels + nb_metadata * 0x14;
+ m->current_block = 0;
+
+ st->start_time = 0;
+ st->codecpar->codec_id = AV_CODEC_ID_ADPCM_THP_LE;
+
+ ret = ff_alloc_extradata(st->codecpar, 32 * st->codecpar->channels);
+ if (ret < 0)
+ return ret;
+
+ ret = avio_seek(s->pb, m->coef_offset, SEEK_SET);
+ if (ret < 0)
+ return ret;
+ for (ch = 0; ch < st->codecpar->channels; ch++) {
+ if (avio_read(s->pb, st->codecpar->extradata + ch * 32, 32) != 32) {
+ return AVERROR_INVALIDDATA;
+ }
+ // 0x30 (alignment) - 0x20 (actual size, 32) = 0x10 (padding)
+ avio_skip(s->pb, 0x10);
+ }
+
+ // seek to the beginning of the adpcm data
+ // there are some files that the adpcm audio data is not immediately after the header
+ ret = avio_seek(s->pb, m->data_start, SEEK_SET);
+ if (ret < 0)
+ return ret;
+
+ return 0;
+}
+
+static int read_packet(AVFormatContext *s, AVPacket *pkt)
+{
+ AVCodecParameters *par = s->streams[0]->codecpar;
+ MCADemuxContext *m = s->priv_data;
+ uint32_t samples, size = 0;
+ int ret, i = 0;
+ uint8_t *dst;
+
+ if (avio_feof(s->pb))
+ return AVERROR_EOF;
+ m->current_block++;
+ size = m->block_size;
+ samples = m->samples_per_block;
+ // adapted from brstm.c
+ if (m->current_block == m->block_count) {
+ if (samples < size * 14 / 8) {
+ uint32_t adjusted_size = samples / 14 * 8;
+ if (samples % 14)
+ adjusted_size += (samples % 14 + 1) / 2 + 1;
+
+ size = adjusted_size;
+ }
+ } else if (m->current_block > m->block_count)
+ return AVERROR_EOF;
+
+ if (size > (INT_MAX - 32 - 4) ||
+ (32 + 4 + size) > (INT_MAX / par->channels) ||
+ (32 + 4 + size) * par->channels > INT_MAX - 8)
+ return AVERROR_INVALIDDATA;
+ if ((ret = av_new_packet(pkt, size * par->channels)) < 0)
+ return ret;
+ dst = pkt->data;
+ for (i = 0; i < par->channels; i++) {
+ ret = avio_read(s->pb, dst, size);
+ dst += size;
+ if (ret != size) {
+ return AVERROR(EIO);
+ }
+ }
+ pkt->duration = samples;
+ pkt->stream_index = 0;
+
+ return ret;
+}
+
+static int read_seek(AVFormatContext *s, int stream_index,
+ int64_t timestamp, int flags)
+{
+ AVStream *st = s->streams[stream_index];
+ MCADemuxContext *m = s->priv_data;
+ int64_t ret = 0;
+
+ timestamp /= m->samples_per_block;
+ ret = avio_seek(s->pb, m->data_start + timestamp * m->block_size *
+ st->codecpar->channels, SEEK_SET);
+
+ if (ret < 0)
+ return ret;
+
+ m->current_block = timestamp;
+ ff_update_cur_dts(s, st, timestamp * m->samples_per_block);
+ return 0;
+}
+
+AVInputFormat ff_mca_demuxer = {
+ .name = "mca",
+ .long_name = NULL_IF_CONFIG_SMALL("MCA Audio Format"),
+ .priv_data_size = sizeof(MCADemuxContext),
+ .read_probe = probe,
+ .read_header = read_header,
+ .read_packet = read_packet,
+ .read_seek = read_seek,
+ .extensions = "mca",
+};
diff --git a/libavformat/version.h b/libavformat/version.h
index 88876ae..146db09 100644
--- a/libavformat/version.h
+++ b/libavformat/version.h
@@ -32,8 +32,8 @@
// Major bumping may affect Ticket5467, 5421, 5451(compatibility with Chromium)
// Also please add any ticket numbers that you believe might be affected here
#define LIBAVFORMAT_VERSION_MAJOR 58
-#define LIBAVFORMAT_VERSION_MINOR 51
-#define LIBAVFORMAT_VERSION_MICRO 101
+#define LIBAVFORMAT_VERSION_MINOR 52
+#define LIBAVFORMAT_VERSION_MICRO 100
#define LIBAVFORMAT_VERSION_INT AV_VERSION_INT(LIBAVFORMAT_VERSION_MAJOR, \
LIBAVFORMAT_VERSION_MINOR, \
--
2.28.0
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