[libav-devel] [PATCH] mmf: split muxer demuxer

Nidhi Makhijani nidhimj22 at gmail.com
Thu Jun 19 20:42:57 CEST 2014


---
 libavformat/Makefile |   4 +-
 libavformat/mmf.c    | 328 ---------------------------------------------------
 libavformat/mmfdec.c | 175 +++++++++++++++++++++++++++
 libavformat/mmfenc.c | 173 +++++++++++++++++++++++++++
 4 files changed, 350 insertions(+), 330 deletions(-)
 delete mode 100644 libavformat/mmf.c
 create mode 100644 libavformat/mmfdec.c
 create mode 100644 libavformat/mmfenc.c

diff --git a/libavformat/Makefile b/libavformat/Makefile
index a7ff117..eb015d8 100644
--- a/libavformat/Makefile
+++ b/libavformat/Makefile
@@ -176,8 +176,8 @@ OBJS-$(CONFIG_MJPEG_MUXER)               += rawenc.o
 OBJS-$(CONFIG_MLP_DEMUXER)               += rawdec.o
 OBJS-$(CONFIG_MLP_MUXER)                 += rawenc.o
 OBJS-$(CONFIG_MM_DEMUXER)                += mm.o
-OBJS-$(CONFIG_MMF_DEMUXER)               += mmf.o pcm.o
-OBJS-$(CONFIG_MMF_MUXER)                 += mmf.o
+OBJS-$(CONFIG_MMF_DEMUXER)               += mmfdec.o pcm.o
+OBJS-$(CONFIG_MMF_MUXER)                 += mmfenc.o
 OBJS-$(CONFIG_MOV_DEMUXER)               += mov.o isom.o mov_chan.o replaygain.o
 OBJS-$(CONFIG_MOV_MUXER)                 += movenc.o isom.o avc.o hevc.o \
                                             movenchint.o mov_chan.o
diff --git a/libavformat/mmf.c b/libavformat/mmf.c
deleted file mode 100644
index 61f1d7a..0000000
--- a/libavformat/mmf.c
+++ /dev/null
@@ -1,328 +0,0 @@
-/*
- * Yamaha SMAF format
- * Copyright (c) 2005 Vidar Madsen
- *
- * 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
- */
-
-#include "libavutil/channel_layout.h"
-#include "avformat.h"
-#include "avio_internal.h"
-#include "internal.h"
-#include "pcm.h"
-#include "riff.h"
-
-typedef struct {
-    int64_t atrpos, atsqpos, awapos;
-    int64_t data_size;
-} MMFContext;
-
-static const int mmf_rates[] = { 4000, 8000, 11025, 22050, 44100 };
-
-static int mmf_rate(int code)
-{
-    if ((code < 0) || (code > 4))
-        return -1;
-    return mmf_rates[code];
-}
-
-#if CONFIG_MMF_MUXER
-static int mmf_rate_code(int rate)
-{
-    int i;
-    for (i = 0; i < 5; i++)
-        if (mmf_rates[i] == rate)
-            return i;
-    return -1;
-}
-
-/* Copy of end_tag() from avienc.c, but for big-endian chunk size */
-static void end_tag_be(AVIOContext *pb, int64_t start)
-{
-    int64_t pos;
-
-    pos = avio_tell(pb);
-    avio_seek(pb, start - 4, SEEK_SET);
-    avio_wb32(pb, (uint32_t)(pos - start));
-    avio_seek(pb, pos, SEEK_SET);
-}
-
-static int mmf_write_header(AVFormatContext *s)
-{
-    MMFContext *mmf = s->priv_data;
-    AVIOContext *pb = s->pb;
-    int64_t pos;
-    int rate;
-
-    rate = mmf_rate_code(s->streams[0]->codec->sample_rate);
-    if (rate < 0) {
-        av_log(s, AV_LOG_ERROR, "Unsupported sample rate %d\n",
-               s->streams[0]->codec->sample_rate);
-        return -1;
-    }
-
-    ffio_wfourcc(pb, "MMMD");
-    avio_wb32(pb, 0);
-    pos = ff_start_tag(pb, "CNTI");
-    avio_w8(pb, 0); /* class */
-    avio_w8(pb, 0); /* type */
-    avio_w8(pb, 0); /* code type */
-    avio_w8(pb, 0); /* status */
-    avio_w8(pb, 0); /* counts */
-    end_tag_be(pb, pos);
-
-    pos = ff_start_tag(pb, "OPDA");
-    avio_write(pb, "VN:libavcodec,", sizeof("VN:libavcodec,") -1); /* metadata ("ST:songtitle,VN:version,...") */
-    end_tag_be(pb, pos);
-
-    avio_write(pb, "ATR\x00", 4);
-    avio_wb32(pb, 0);
-    mmf->atrpos = avio_tell(pb);
-    avio_w8(pb, 0); /* format type */
-    avio_w8(pb, 0); /* sequence type */
-    avio_w8(pb, (0 << 7) | (1 << 4) | rate); /* (channel << 7) | (format << 4) | rate */
-    avio_w8(pb, 0); /* wave base bit */
-    avio_w8(pb, 2); /* time base d */
-    avio_w8(pb, 2); /* time base g */
-
-    ffio_wfourcc(pb, "Atsq");
-    avio_wb32(pb, 16);
-    mmf->atsqpos = avio_tell(pb);
-    /* Will be filled on close */
-    avio_write(pb, "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00", 16);
-
-    mmf->awapos = ff_start_tag(pb, "Awa\x01");
-
-    avpriv_set_pts_info(s->streams[0], 64, 1, s->streams[0]->codec->sample_rate);
-
-    avio_flush(pb);
-
-    return 0;
-}
-
-static int mmf_write_packet(AVFormatContext *s, AVPacket *pkt)
-{
-    AVIOContext *pb = s->pb;
-    avio_write(pb, pkt->data, pkt->size);
-    return 0;
-}
-
-/* Write a variable-length symbol */
-static void put_varlength(AVIOContext *pb, int val)
-{
-    if (val < 128)
-        avio_w8(pb, val);
-    else {
-        val -= 128;
-        avio_w8(pb, 0x80 | val >> 7);
-        avio_w8(pb, 0x7f & val);
-    }
-}
-
-static int mmf_write_trailer(AVFormatContext *s)
-{
-    AVIOContext *pb = s->pb;
-    MMFContext *mmf = s->priv_data;
-    int64_t pos, size;
-    int gatetime;
-
-    if (s->pb->seekable) {
-        /* Fill in length fields */
-        end_tag_be(pb, mmf->awapos);
-        end_tag_be(pb, mmf->atrpos);
-        end_tag_be(pb, 8);
-
-        pos  = avio_tell(pb);
-        size = pos - mmf->awapos;
-
-        /* Fill Atsq chunk */
-        avio_seek(pb, mmf->atsqpos, SEEK_SET);
-
-        /* "play wav" */
-        avio_w8(pb, 0); /* start time */
-        avio_w8(pb, 1); /* (channel << 6) | wavenum */
-        gatetime = size * 500 / s->streams[0]->codec->sample_rate;
-        put_varlength(pb, gatetime); /* duration */
-
-        /* "nop" */
-        put_varlength(pb, gatetime); /* start time */
-        avio_write(pb, "\xff\x00", 2); /* nop */
-
-        /* "end of sequence" */
-        avio_write(pb, "\x00\x00\x00\x00", 4);
-
-        avio_seek(pb, pos, SEEK_SET);
-
-        avio_flush(pb);
-    }
-    return 0;
-}
-#endif /* CONFIG_MMF_MUXER */
-
-static int mmf_probe(AVProbeData *p)
-{
-    /* check file header */
-    if (p->buf[0] == 'M' && p->buf[1] == 'M' &&
-        p->buf[2] == 'M' && p->buf[3] == 'D' &&
-        p->buf[8] == 'C' && p->buf[9] == 'N' &&
-        p->buf[10] == 'T' && p->buf[11] == 'I')
-        return AVPROBE_SCORE_MAX;
-    else
-        return 0;
-}
-
-/* mmf input */
-static int mmf_read_header(AVFormatContext *s)
-{
-    MMFContext *mmf = s->priv_data;
-    unsigned int tag;
-    AVIOContext *pb = s->pb;
-    AVStream *st;
-    int64_t size;
-    int rate, params;
-
-    tag = avio_rl32(pb);
-    if (tag != MKTAG('M', 'M', 'M', 'D'))
-        return -1;
-    avio_skip(pb, 4); /* file_size */
-
-    /* Skip some unused chunks that may or may not be present */
-    for (;; avio_skip(pb, size)) {
-        tag  = avio_rl32(pb);
-        size = avio_rb32(pb);
-        if (tag == MKTAG('C', 'N', 'T', 'I'))
-            continue;
-        if (tag == MKTAG('O', 'P', 'D', 'A'))
-            continue;
-        break;
-    }
-
-    /* Tag = "ATRx", where "x" = track number */
-    if ((tag & 0xffffff) == MKTAG('M', 'T', 'R', 0)) {
-        av_log(s, AV_LOG_ERROR, "MIDI like format found, unsupported\n");
-        return -1;
-    }
-    if ((tag & 0xffffff) != MKTAG('A', 'T', 'R', 0)) {
-        av_log(s, AV_LOG_ERROR, "Unsupported SMAF chunk %08x\n", tag);
-        return -1;
-    }
-
-    avio_r8(pb); /* format type */
-    avio_r8(pb); /* sequence type */
-    params = avio_r8(pb); /* (channel << 7) | (format << 4) | rate */
-    rate   = mmf_rate(params & 0x0f);
-    if (rate < 0) {
-        av_log(s, AV_LOG_ERROR, "Invalid sample rate\n");
-        return -1;
-    }
-    avio_r8(pb); /* wave base bit */
-    avio_r8(pb); /* time base d */
-    avio_r8(pb); /* time base g */
-
-    /* Skip some unused chunks that may or may not be present */
-    for (;; avio_skip(pb, size)) {
-        tag  = avio_rl32(pb);
-        size = avio_rb32(pb);
-        if (tag == MKTAG('A', 't', 's', 'q'))
-            continue;
-        if (tag == MKTAG('A', 's', 'p', 'I'))
-            continue;
-        break;
-    }
-
-    /* Make sure it's followed by an Awa chunk, aka wave data */
-    if ((tag & 0xffffff) != MKTAG('A', 'w', 'a', 0)) {
-        av_log(s, AV_LOG_ERROR, "Unexpected SMAF chunk %08x\n", tag);
-        return -1;
-    }
-    mmf->data_size = size;
-
-    st = avformat_new_stream(s, NULL);
-    if (!st)
-        return AVERROR(ENOMEM);
-
-    st->codec->codec_type            = AVMEDIA_TYPE_AUDIO;
-    st->codec->codec_id              = AV_CODEC_ID_ADPCM_YAMAHA;
-    st->codec->sample_rate           = rate;
-    st->codec->channels              = 1;
-    st->codec->channel_layout        = AV_CH_LAYOUT_MONO;
-    st->codec->bits_per_coded_sample = 4;
-    st->codec->bit_rate              = st->codec->sample_rate *
-                                       st->codec->bits_per_coded_sample;
-
-    avpriv_set_pts_info(st, 64, 1, st->codec->sample_rate);
-
-    return 0;
-}
-
-#define MAX_SIZE 4096
-
-static int mmf_read_packet(AVFormatContext *s, AVPacket *pkt)
-{
-    MMFContext *mmf = s->priv_data;
-    int ret, size;
-
-    if (s->pb->eof_reached)
-        return AVERROR(EIO);
-
-    size = MAX_SIZE;
-    if (size > mmf->data_size)
-        size = mmf->data_size;
-
-    if (!size)
-        return AVERROR(EIO);
-
-    if (av_new_packet(pkt, size))
-        return AVERROR(EIO);
-    pkt->stream_index = 0;
-
-    ret = avio_read(s->pb, pkt->data, pkt->size);
-    if (ret < 0)
-        av_free_packet(pkt);
-
-    mmf->data_size -= ret;
-
-    pkt->size = ret;
-    return ret;
-}
-
-#if CONFIG_MMF_DEMUXER
-AVInputFormat ff_mmf_demuxer = {
-    .name           = "mmf",
-    .long_name      = NULL_IF_CONFIG_SMALL("Yamaha SMAF"),
-    .priv_data_size = sizeof(MMFContext),
-    .read_probe     = mmf_probe,
-    .read_header    = mmf_read_header,
-    .read_packet    = mmf_read_packet,
-    .read_seek      = ff_pcm_read_seek,
-};
-#endif
-
-#if CONFIG_MMF_MUXER
-AVOutputFormat ff_mmf_muxer = {
-    .name           = "mmf",
-    .long_name      = NULL_IF_CONFIG_SMALL("Yamaha SMAF"),
-    .mime_type      = "application/vnd.smaf",
-    .extensions     = "mmf",
-    .priv_data_size = sizeof(MMFContext),
-    .audio_codec    = AV_CODEC_ID_ADPCM_YAMAHA,
-    .video_codec    = AV_CODEC_ID_NONE,
-    .write_header   = mmf_write_header,
-    .write_packet   = mmf_write_packet,
-    .write_trailer  = mmf_write_trailer,
-};
-#endif
diff --git a/libavformat/mmfdec.c b/libavformat/mmfdec.c
new file mode 100644
index 0000000..de6178e
--- /dev/null
+++ b/libavformat/mmfdec.c
@@ -0,0 +1,175 @@
+/*
+ * Yamaha SMAF demuxer
+ * Copyright (c) 2005 Vidar Madsen
+ *
+ * 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
+ */
+
+#include "libavutil/channel_layout.h"
+#include "internal.h"
+#include "pcm.h"
+
+typedef struct {
+    int64_t data_size;
+} MMFContext;
+
+static const int mmf_rates[] = { 4000, 8000, 11025, 22050, 44100 };
+
+static int mmf_rate(int code)
+{
+    if ((code < 0) || (code > 4))
+        return -1;
+    return mmf_rates[code];
+}
+
+static int mmf_probe(AVProbeData *p)
+{
+    /* check file header */
+    if (p->buf[0] == 'M' && p->buf[1] == 'M' &&
+        p->buf[2] == 'M' && p->buf[3] == 'D' &&
+        p->buf[8] == 'C' && p->buf[9] == 'N' &&
+        p->buf[10] == 'T' && p->buf[11] == 'I')
+        return AVPROBE_SCORE_MAX;
+    else
+        return 0;
+}
+
+/* mmf input */
+static int mmf_read_header(AVFormatContext *s)
+{
+    MMFContext *mmf = s->priv_data;
+    unsigned int tag;
+    AVIOContext *pb = s->pb;
+    AVStream *st;
+    int64_t size;
+    int rate, params;
+
+    tag = avio_rl32(pb);
+    if (tag != MKTAG('M', 'M', 'M', 'D'))
+        return -1;
+    avio_skip(pb, 4); /* file_size */
+
+    /* Skip some unused chunks that may or may not be present */
+    for (;; avio_skip(pb, size)) {
+        tag  = avio_rl32(pb);
+        size = avio_rb32(pb);
+        if (tag == MKTAG('C', 'N', 'T', 'I'))
+            continue;
+        if (tag == MKTAG('O', 'P', 'D', 'A'))
+            continue;
+        break;
+    }
+
+    /* Tag = "ATRx", where "x" = track number */
+    if ((tag & 0xffffff) == MKTAG('M', 'T', 'R', 0)) {
+        av_log(s, AV_LOG_ERROR, "MIDI like format found, unsupported\n");
+        return -1;
+    }
+    if ((tag & 0xffffff) != MKTAG('A', 'T', 'R', 0)) {
+        av_log(s, AV_LOG_ERROR, "Unsupported SMAF chunk %08x\n", tag);
+        return -1;
+    }
+
+    avio_r8(pb); /* format type */
+    avio_r8(pb); /* sequence type */
+    params = avio_r8(pb); /* (channel << 7) | (format << 4) | rate */
+    rate   = mmf_rate(params & 0x0f);
+    if (rate < 0) {
+        av_log(s, AV_LOG_ERROR, "Invalid sample rate\n");
+        return -1;
+    }
+    avio_r8(pb); /* wave base bit */
+    avio_r8(pb); /* time base d */
+    avio_r8(pb); /* time base g */
+
+    /* Skip some unused chunks that may or may not be present */
+    for (;; avio_skip(pb, size)) {
+        tag  = avio_rl32(pb);
+        size = avio_rb32(pb);
+        if (tag == MKTAG('A', 't', 's', 'q'))
+            continue;
+        if (tag == MKTAG('A', 's', 'p', 'I'))
+            continue;
+        break;
+    }
+
+    /* Make sure it's followed by an Awa chunk, aka wave data */
+    if ((tag & 0xffffff) != MKTAG('A', 'w', 'a', 0)) {
+        av_log(s, AV_LOG_ERROR, "Unexpected SMAF chunk %08x\n", tag);
+        return -1;
+    }
+    mmf->data_size = size;
+
+    st = avformat_new_stream(s, NULL);
+    if (!st)
+        return AVERROR(ENOMEM);
+
+    st->codec->codec_type            = AVMEDIA_TYPE_AUDIO;
+    st->codec->codec_id              = AV_CODEC_ID_ADPCM_YAMAHA;
+    st->codec->sample_rate           = rate;
+    st->codec->channels              = 1;
+    st->codec->channel_layout        = AV_CH_LAYOUT_MONO;
+    st->codec->bits_per_coded_sample = 4;
+    st->codec->bit_rate              = st->codec->sample_rate *
+                                       st->codec->bits_per_coded_sample;
+
+    avpriv_set_pts_info(st, 64, 1, st->codec->sample_rate);
+
+    return 0;
+}
+
+#define MAX_SIZE 4096
+
+static int mmf_read_packet(AVFormatContext *s, AVPacket *pkt)
+{
+    MMFContext *mmf = s->priv_data;
+    int ret, size;
+
+    if (s->pb->eof_reached)
+        return AVERROR(EIO);
+
+    size = MAX_SIZE;
+    if (size > mmf->data_size)
+        size = mmf->data_size;
+
+    if (!size)
+        return AVERROR(EIO);
+
+    if (av_new_packet(pkt, size))
+        return AVERROR(EIO);
+    pkt->stream_index = 0;
+
+    ret = avio_read(s->pb, pkt->data, pkt->size);
+    if (ret < 0)
+        av_free_packet(pkt);
+
+    mmf->data_size -= ret;
+
+    pkt->size = ret;
+    return ret;
+}
+
+AVInputFormat ff_mmf_demuxer = {
+    .name           = "mmf",
+    .long_name      = NULL_IF_CONFIG_SMALL("Yamaha SMAF"),
+    .priv_data_size = sizeof(MMFContext),
+    .read_probe     = mmf_probe,
+    .read_header    = mmf_read_header,
+    .read_packet    = mmf_read_packet,
+    .read_seek      = ff_pcm_read_seek,
+};
+
diff --git a/libavformat/mmfenc.c b/libavformat/mmfenc.c
new file mode 100644
index 0000000..c02466d
--- /dev/null
+++ b/libavformat/mmfenc.c
@@ -0,0 +1,173 @@
+/*
+ * Yamaha SMAF muxer
+ * Copyright (c) 2005 Vidar Madsen
+ *
+ * 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
+ */
+
+#include "avio_internal.h"
+#include "riff.h"
+
+typedef struct {
+    int64_t atrpos, atsqpos, awapos;
+} MMFContext;
+
+static const int mmf_rates[] = { 4000, 8000, 11025, 22050, 44100 };
+
+static int mmf_rate_code(int rate)
+{
+    int i;
+    for (i = 0; i < 5; i++)
+        if (mmf_rates[i] == rate)
+            return i;
+    return -1;
+}
+
+/* Copy of end_tag() from avienc.c, but for big-endian chunk size */
+static void end_tag_be(AVIOContext *pb, int64_t start)
+{
+    int64_t pos;
+
+    pos = avio_tell(pb);
+    avio_seek(pb, start - 4, SEEK_SET);
+    avio_wb32(pb, (uint32_t)(pos - start));
+    avio_seek(pb, pos, SEEK_SET);
+}
+
+static int mmf_write_header(AVFormatContext *s)
+{
+    MMFContext *mmf = s->priv_data;
+    AVIOContext *pb = s->pb;
+    int64_t pos;
+    int rate;
+
+    rate = mmf_rate_code(s->streams[0]->codec->sample_rate);
+    if (rate < 0) {
+        av_log(s, AV_LOG_ERROR, "Unsupported sample rate %d\n",
+               s->streams[0]->codec->sample_rate);
+        return -1;
+    }
+
+    ffio_wfourcc(pb, "MMMD");
+    avio_wb32(pb, 0);
+    pos = ff_start_tag(pb, "CNTI");
+    avio_w8(pb, 0); /* class */
+    avio_w8(pb, 0); /* type */
+    avio_w8(pb, 0); /* code type */
+    avio_w8(pb, 0); /* status */
+    avio_w8(pb, 0); /* counts */
+    end_tag_be(pb, pos);
+
+    pos = ff_start_tag(pb, "OPDA");
+    avio_write(pb, "VN:libavcodec,", sizeof("VN:libavcodec,") -1); /* metadata ("ST:songtitle,VN:version,...") */
+    end_tag_be(pb, pos);
+
+    avio_write(pb, "ATR\x00", 4);
+    avio_wb32(pb, 0);
+    mmf->atrpos = avio_tell(pb);
+    avio_w8(pb, 0); /* format type */
+    avio_w8(pb, 0); /* sequence type */
+    avio_w8(pb, (0 << 7) | (1 << 4) | rate); /* (channel << 7) | (format << 4) | rate */
+    avio_w8(pb, 0); /* wave base bit */
+    avio_w8(pb, 2); /* time base d */
+    avio_w8(pb, 2); /* time base g */
+
+    ffio_wfourcc(pb, "Atsq");
+    avio_wb32(pb, 16);
+    mmf->atsqpos = avio_tell(pb);
+    /* Will be filled on close */
+    avio_write(pb, "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00", 16);
+
+    mmf->awapos = ff_start_tag(pb, "Awa\x01");
+
+    avpriv_set_pts_info(s->streams[0], 64, 1, s->streams[0]->codec->sample_rate);
+
+    avio_flush(pb);
+
+    return 0;
+}
+
+static int mmf_write_packet(AVFormatContext *s, AVPacket *pkt)
+{
+    AVIOContext *pb = s->pb;
+    avio_write(pb, pkt->data, pkt->size);
+    return 0;
+}
+
+/* Write a variable-length symbol */
+static void put_varlength(AVIOContext *pb, int val)
+{
+    if (val < 128)
+        avio_w8(pb, val);
+    else {
+        val -= 128;
+        avio_w8(pb, 0x80 | val >> 7);
+        avio_w8(pb, 0x7f & val);
+    }
+}
+
+static int mmf_write_trailer(AVFormatContext *s)
+{
+    AVIOContext *pb = s->pb;
+    MMFContext *mmf = s->priv_data;
+    int64_t pos, size;
+    int gatetime;
+
+    if (s->pb->seekable) {
+        /* Fill in length fields */
+        end_tag_be(pb, mmf->awapos);
+        end_tag_be(pb, mmf->atrpos);
+        end_tag_be(pb, 8);
+
+        pos  = avio_tell(pb);
+        size = pos - mmf->awapos;
+
+        /* Fill Atsq chunk */
+        avio_seek(pb, mmf->atsqpos, SEEK_SET);
+
+        /* "play wav" */
+        avio_w8(pb, 0); /* start time */
+        avio_w8(pb, 1); /* (channel << 6) | wavenum */
+        gatetime = size * 500 / s->streams[0]->codec->sample_rate;
+        put_varlength(pb, gatetime); /* duration */
+
+        /* "nop" */
+        put_varlength(pb, gatetime); /* start time */
+        avio_write(pb, "\xff\x00", 2); /* nop */
+
+        /* "end of sequence" */
+        avio_write(pb, "\x00\x00\x00\x00", 4);
+
+        avio_seek(pb, pos, SEEK_SET);
+
+        avio_flush(pb);
+    }
+    return 0;
+}
+
+AVOutputFormat ff_mmf_muxer = {
+    .name           = "mmf",
+    .long_name      = NULL_IF_CONFIG_SMALL("Yamaha SMAF"),
+    .mime_type      = "application/vnd.smaf",
+    .extensions     = "mmf",
+    .priv_data_size = sizeof(MMFContext),
+    .audio_codec    = AV_CODEC_ID_ADPCM_YAMAHA,
+    .video_codec    = AV_CODEC_ID_NONE,
+    .write_header   = mmf_write_header,
+    .write_packet   = mmf_write_packet,
+    .write_trailer  = mmf_write_trailer,
+};
-- 
1.9.1



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