[FFmpeg-devel] [PATCH 2/4] avformat: add demuxer for LEGO Racers' ALP format
Zane van Iperen
zane at zanevaniperen.com
Thu Mar 5 02:40:36 EET 2020
Signed-off-by: Zane van Iperen <zane at zanevaniperen.com>
---
libavformat/Makefile | 1 +
libavformat/allformats.c | 1 +
libavformat/alp.c | 135 +++++++++++++++++++++++++++++++++++++++
libavformat/version.h | 4 +-
4 files changed, 139 insertions(+), 2 deletions(-)
create mode 100644 libavformat/alp.c
diff --git a/libavformat/Makefile b/libavformat/Makefile
index e0681058a2..fbb29505ff 100644
--- a/libavformat/Makefile
+++ b/libavformat/Makefile
@@ -85,6 +85,7 @@ OBJS-$(CONFIG_AIFF_DEMUXER) += aiffdec.o pcm.o isom.o \
mov_chan.o replaygain.o
OBJS-$(CONFIG_AIFF_MUXER) += aiffenc.o id3v2enc.o
OBJS-$(CONFIG_AIX_DEMUXER) += aixdec.o
+OBJS-$(CONFIG_ALP_DEMUXER) += alp.o
OBJS-$(CONFIG_AMR_DEMUXER) += amr.o
OBJS-$(CONFIG_AMR_MUXER) += amr.o
OBJS-$(CONFIG_AMRNB_DEMUXER) += amr.o
diff --git a/libavformat/allformats.c b/libavformat/allformats.c
index 0209bf0e30..08012ea208 100644
--- a/libavformat/allformats.c
+++ b/libavformat/allformats.c
@@ -46,6 +46,7 @@ extern AVInputFormat ff_afc_demuxer;
extern AVInputFormat ff_aiff_demuxer;
extern AVOutputFormat ff_aiff_muxer;
extern AVInputFormat ff_aix_demuxer;
+extern AVInputFormat ff_alp_demuxer;
extern AVInputFormat ff_amr_demuxer;
extern AVOutputFormat ff_amr_muxer;
extern AVInputFormat ff_amrnb_demuxer;
diff --git a/libavformat/alp.c b/libavformat/alp.c
new file mode 100644
index 0000000000..76703e7ad1
--- /dev/null
+++ b/libavformat/alp.c
@@ -0,0 +1,135 @@
+/*
+ * LEGO Racers ALP (.tun & .pcm) demuxer
+ *
+ * Copyright (C) 2020 Zane van Iperen (zane at zanevaniperen.com)
+ *
+ * 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 "avformat.h"
+#include "internal.h"
+#include "libavutil/intreadwrite.h"
+
+#define ALP_TAG MKTAG('A', 'L', 'P', ' ')
+#define ALP_MAX_READ_SIZE 4096
+
+typedef struct ALPHeader {
+ uint32_t magic; /*< Magic Number, {'A', 'L', 'P', ' '} */
+ uint32_t header_size; /*< Header size (after this). */
+ char adpcm[6]; /*< "ADPCM" */
+ uint8_t unk1; /*< Unknown */
+ uint8_t num_channels; /*< Channel Count. */
+ uint32_t sample_rate; /*< Sample rate, only if header_size >= 12. */
+} ALPHeader;
+
+static int alp_probe(const AVProbeData *p)
+{
+ if (AV_RL32(p->buf) != ALP_TAG)
+ return 0;
+
+ if (AV_RL32(p->buf) < 8)
+ return 0;
+
+ return AVPROBE_SCORE_EXTENSION + 1;
+}
+
+static int alp_read_header(AVFormatContext *s)
+{
+ int ret;
+ AVStream *st;
+ ALPHeader hdr;
+ AVCodecParameters *par;
+
+ memset(&hdr, 0, sizeof(hdr));
+
+ if (!(st = avformat_new_stream(s, NULL)))
+ return AVERROR(ENOMEM);
+
+ if ((hdr.magic = avio_rl32(s->pb)) != ALP_TAG)
+ return AVERROR_INVALIDDATA;
+
+ hdr.header_size = avio_rl32(s->pb);
+
+ if (hdr.header_size != 8 && hdr.header_size != 12) {
+ return AVERROR_INVALIDDATA;
+ }
+
+ if ((ret = avio_read(s->pb, hdr.adpcm, sizeof(hdr.adpcm))) < 0)
+ return ret;
+ else if (ret != sizeof(hdr.adpcm))
+ return AVERROR(EIO);
+
+ if (strncmp("ADPCM", hdr.adpcm, sizeof(hdr.adpcm)) != 0)
+ return AVERROR_INVALIDDATA;
+
+ hdr.unk1 = avio_r8(s->pb);
+ hdr.num_channels = avio_r8(s->pb);
+
+ if (hdr.header_size == 8) {
+ /* .TUN music file */
+ hdr.sample_rate = 11025 * hdr.num_channels;
+ } else {
+ /* .PCM sound file */
+ hdr.sample_rate = avio_rl32(s->pb);
+ }
+
+ par = st->codecpar;
+ par->codec_type = AVMEDIA_TYPE_AUDIO;
+ par->codec_id = AV_CODEC_ID_ADPCM_IMA_ALP;
+ par->format = AV_SAMPLE_FMT_S16;
+ par->sample_rate = hdr.sample_rate;
+ par->channels = hdr.num_channels;
+
+ if (hdr.num_channels == 1)
+ par->channel_layout = AV_CH_LAYOUT_MONO;
+ else if (hdr.num_channels == 2)
+ par->channel_layout = AV_CH_LAYOUT_STEREO;
+ else
+ return AVERROR_INVALIDDATA;
+
+ par->bits_per_coded_sample = 4;
+ par->bits_per_raw_sample = 16;
+ par->block_align = 1;
+ par->bit_rate = par->channels *
+ par->sample_rate *
+ par->bits_per_coded_sample;
+
+ avpriv_set_pts_info(st, 64, 1, par->sample_rate);
+ return 0;
+}
+
+static int alp_read_packet(AVFormatContext *s, AVPacket *pkt)
+{
+ int ret;
+ AVCodecParameters *par = s->streams[0]->codecpar;
+
+ if ((ret = av_get_packet(s->pb, pkt, ALP_MAX_READ_SIZE)) < 0)
+ return ret;
+
+ pkt->flags &= ~AV_PKT_FLAG_CORRUPT;
+ pkt->stream_index = 0;
+ pkt->duration = ret * (8 / par->bits_per_coded_sample) / par->channels;
+
+ return 0;
+}
+
+AVInputFormat ff_alp_demuxer = {
+ .name = "alp",
+ .long_name = NULL_IF_CONFIG_SMALL("LEGO Racers ALP"),
+ .read_probe = alp_probe,
+ .read_header = alp_read_header,
+ .read_packet = alp_read_packet
+};
diff --git a/libavformat/version.h b/libavformat/version.h
index 4724269b3c..a233b67351 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 39
-#define LIBAVFORMAT_VERSION_MICRO 101
+#define LIBAVFORMAT_VERSION_MINOR 40
+#define LIBAVFORMAT_VERSION_MICRO 100
#define LIBAVFORMAT_VERSION_INT AV_VERSION_INT(LIBAVFORMAT_VERSION_MAJOR, \
LIBAVFORMAT_VERSION_MINOR, \
--
2.17.1
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