making act segmenter

1 files changed, 999 insertions, 0 deletions

diff --git a/ffmpeg/libavformat/gxfenc.c b/ffmpeg/libavformat/gxfenc.c
new file mode 100644
index 0000000..28acb74
--- /dev/null
+++ b/ffmpeg/libavformat/gxfenc.c
@@ -0,0 +1,999 @@
+/*
+ * GXF muxer.
+ * Copyright (c) 2006 SmartJog S.A., Baptiste Coudurier <baptiste dot coudurier at smartjog dot 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 "libavutil/avassert.h"
+#include "libavutil/intfloat.h"
+#include "libavutil/opt.h"
+#include "libavutil/mathematics.h"
+#include "libavutil/timecode.h"
+#include "avformat.h"
+#include "internal.h"
+#include "gxf.h"
+#include "audiointerleave.h"
+
+#define GXF_AUDIO_PACKET_SIZE 65536
+
+#define GXF_TIMECODE(c, d, h, m, s, f) \
+    ((c) << 30 | (d) << 29 | (h) << 24 | (m) << 16 | (s) << 8 | (f))
+
+typedef struct GXFTimecode{
+    int hh;
+    int mm;
+    int ss;
+    int ff;
+    int color;
+    int drop;
+} GXFTimecode;
+
+typedef struct GXFStreamContext {
+    AudioInterleaveContext aic;
+    uint32_t track_type;
+    uint32_t sample_size;
+    uint32_t sample_rate;
+    uint16_t media_type;
+    uint16_t media_info;
+    int frame_rate_index;
+    int lines_index;
+    int fields;
+    int iframes;
+    int pframes;
+    int bframes;
+    int p_per_gop;
+    int b_per_i_or_p; ///< number of B frames per I frame or P frame
+    int first_gop_closed;
+    unsigned order;   ///< interleaving order
+} GXFStreamContext;
+
+typedef struct GXFContext {
+    AVClass *av_class;
+    uint32_t nb_fields;
+    uint16_t audio_tracks;
+    uint16_t mpeg_tracks;
+    int64_t creation_time;
+    uint32_t umf_start_offset;
+    uint32_t umf_track_offset;
+    uint32_t umf_media_offset;
+    uint32_t umf_length;
+    uint16_t umf_track_size;
+    uint16_t umf_media_size;
+    AVRational time_base;
+    int flags;
+    GXFStreamContext timecode_track;
+    unsigned *flt_entries;    ///< offsets of packets /1024, starts after 2nd video field
+    unsigned flt_entries_nb;
+    uint64_t *map_offsets;    ///< offset of map packets
+    unsigned map_offsets_nb;
+    unsigned packet_count;
+    GXFTimecode tc;
+} GXFContext;
+
+static const struct {
+    int height, index;
+} gxf_lines_tab[] = {
+    { 480,  1 }, /* NTSC */
+    { 512,  1 }, /* NTSC + VBI */
+    { 576,  2 }, /* PAL */
+    { 608,  2 }, /* PAL + VBI */
+    { 1080, 4 },
+    { 720,  6 },
+};
+
+static const AVCodecTag gxf_media_types[] = {
+    { AV_CODEC_ID_MJPEG     ,   3 }, /* NTSC */
+    { AV_CODEC_ID_MJPEG     ,   4 }, /* PAL */
+    { AV_CODEC_ID_PCM_S24LE ,   9 },
+    { AV_CODEC_ID_PCM_S16LE ,  10 },
+    { AV_CODEC_ID_MPEG2VIDEO,  11 }, /* NTSC */
+    { AV_CODEC_ID_MPEG2VIDEO,  12 }, /* PAL */
+    { AV_CODEC_ID_DVVIDEO   ,  13 }, /* NTSC */
+    { AV_CODEC_ID_DVVIDEO   ,  14 }, /* PAL */
+    { AV_CODEC_ID_DVVIDEO   ,  15 }, /* 50M NTSC */
+    { AV_CODEC_ID_DVVIDEO   ,  16 }, /* 50M PAL */
+    { AV_CODEC_ID_AC3       ,  17 },
+    //{ AV_CODEC_ID_NONE,  ,   18 }, /* Non compressed 24 bit audio */
+    { AV_CODEC_ID_MPEG2VIDEO,  20 }, /* MPEG HD */
+    { AV_CODEC_ID_MPEG1VIDEO,  22 }, /* NTSC */
+    { AV_CODEC_ID_MPEG1VIDEO,  23 }, /* PAL */
+    { AV_CODEC_ID_NONE,         0 },
+};
+
+#define SERVER_PATH "EXT:/PDR/default/"
+#define ES_NAME_PATTERN "EXT:/PDR/default/ES."
+
+static int gxf_find_lines_index(AVStream *st)
+{
+    GXFStreamContext *sc = st->priv_data;
+    int i;
+
+    for (i = 0; i < 6; ++i) {
+        if (st->codec->height == gxf_lines_tab[i].height) {
+            sc->lines_index = gxf_lines_tab[i].index;
+            return 0;
+        }
+    }
+    return -1;
+}
+
+static void gxf_write_padding(AVIOContext *pb, int64_t to_pad)
+{
+    for (; to_pad > 0; to_pad--) {
+        avio_w8(pb, 0);
+    }
+}
+
+static int64_t updatePacketSize(AVIOContext *pb, int64_t pos)
+{
+    int64_t curpos;
+    int size;
+
+    size = avio_tell(pb) - pos;
+    if (size % 4) {
+        gxf_write_padding(pb, 4 - size % 4);
+        size = avio_tell(pb) - pos;
+    }
+    curpos = avio_tell(pb);
+    avio_seek(pb, pos + 6, SEEK_SET);
+    avio_wb32(pb, size);
+    avio_seek(pb, curpos, SEEK_SET);
+    return curpos - pos;
+}
+
+static int64_t updateSize(AVIOContext *pb, int64_t pos)
+{
+    int64_t curpos;
+
+    curpos = avio_tell(pb);
+    avio_seek(pb, pos, SEEK_SET);
+    avio_wb16(pb, curpos - pos - 2);
+    avio_seek(pb, curpos, SEEK_SET);
+    return curpos - pos;
+}
+
+static void gxf_write_packet_header(AVIOContext *pb, GXFPktType type)
+{
+    avio_wb32(pb, 0);  /* packet leader for synchro */
+    avio_w8(pb, 1);
+    avio_w8(pb, type); /* map packet */
+    avio_wb32(pb, 0);  /* size */
+    avio_wb32(pb, 0);  /* reserved */
+    avio_w8(pb, 0xE1); /* trailer 1 */
+    avio_w8(pb, 0xE2); /* trailer 2 */
+}
+
+static int gxf_write_mpeg_auxiliary(AVIOContext *pb, AVStream *st)
+{
+    GXFStreamContext *sc = st->priv_data;
+    char buffer[1024];
+    int size, starting_line;
+
+    if (sc->iframes) {
+        sc->p_per_gop = sc->pframes / sc->iframes;
+        if (sc->pframes % sc->iframes)
+            sc->p_per_gop++;
+        if (sc->pframes) {
+            sc->b_per_i_or_p = sc->bframes / sc->pframes;
+            if (sc->bframes % sc->pframes)
+                sc->b_per_i_or_p++;
+        }
+        if (sc->p_per_gop > 9)
+            sc->p_per_gop = 9; /* ensure value won't take more than one char */
+        if (sc->b_per_i_or_p > 9)
+            sc->b_per_i_or_p = 9; /* ensure value won't take more than one char */
+    }
+    if (st->codec->height == 512 || st->codec->height == 608)
+        starting_line = 7; // VBI
+    else if (st->codec->height == 480)
+        starting_line = 20;
+    else
+        starting_line = 23; // default PAL
+
+    size = snprintf(buffer, sizeof(buffer), "Ver 1\nBr %.6f\nIpg 1\nPpi %d\nBpiop %d\n"
+                    "Pix 0\nCf %d\nCg %d\nSl %d\nnl16 %d\nVi 1\nf1 1\n",
+                    (float)st->codec->bit_rate, sc->p_per_gop, sc->b_per_i_or_p,
+                    st->codec->pix_fmt == AV_PIX_FMT_YUV422P ? 2 : 1, sc->first_gop_closed == 1,
+                    starting_line, (st->codec->height + 15) / 16);
+    av_assert0(size < sizeof(buffer));
+    avio_w8(pb, TRACK_MPG_AUX);
+    avio_w8(pb, size + 1);
+    avio_write(pb, (uint8_t *)buffer, size + 1);
+    return size + 3;
+}
+
+static int gxf_write_timecode_auxiliary(AVIOContext *pb, GXFContext *gxf)
+{
+    uint32_t timecode = GXF_TIMECODE(gxf->tc.color, gxf->tc.drop,
+                                     gxf->tc.hh, gxf->tc.mm,
+                                     gxf->tc.ss, gxf->tc.ff);
+
+    avio_wl32(pb, timecode);
+    /* reserved */
+    avio_wl32(pb, 0);
+    return 8;
+}
+
+static int gxf_write_track_description(AVFormatContext *s, GXFStreamContext *sc, int index)
+{
+    GXFContext *gxf = s->priv_data;
+    AVIOContext *pb = s->pb;
+    int64_t pos;
+    int mpeg = sc->track_type == 4 || sc->track_type == 9;
+
+    /* track description section */
+    avio_w8(pb, sc->media_type + 0x80);
+    avio_w8(pb, index + 0xC0);
+
+    pos = avio_tell(pb);
+    avio_wb16(pb, 0); /* size */
+
+    /* media file name */
+    avio_w8(pb, TRACK_NAME);
+    avio_w8(pb, strlen(ES_NAME_PATTERN) + 3);
+    avio_write(pb, ES_NAME_PATTERN, sizeof(ES_NAME_PATTERN) - 1);
+    avio_wb16(pb, sc->media_info);
+    avio_w8(pb, 0);
+
+    if (!mpeg) {
+        /* auxiliary information */
+        avio_w8(pb, TRACK_AUX);
+        avio_w8(pb, 8);
+        if (sc->track_type == 3)
+            gxf_write_timecode_auxiliary(pb, gxf);
+        else
+            avio_wl64(pb, 0);
+    }
+
+    /* file system version */
+    avio_w8(pb, TRACK_VER);
+    avio_w8(pb, 4);
+    avio_wb32(pb, 0);
+
+    if (mpeg)
+        gxf_write_mpeg_auxiliary(pb, s->streams[index]);
+
+    /* frame rate */
+    avio_w8(pb, TRACK_FPS);
+    avio_w8(pb, 4);
+    avio_wb32(pb, sc->frame_rate_index);
+
+    /* lines per frame */
+    avio_w8(pb, TRACK_LINES);
+    avio_w8(pb, 4);
+    avio_wb32(pb, sc->lines_index);
+
+    /* fields per frame */
+    avio_w8(pb, TRACK_FPF);
+    avio_w8(pb, 4);
+    avio_wb32(pb, sc->fields);
+
+    return updateSize(pb, pos);
+}
+
+static int gxf_write_material_data_section(AVFormatContext *s)
+{
+    GXFContext *gxf = s->priv_data;
+    AVIOContext *pb = s->pb;
+    int64_t pos;
+    int len;
+    const char *filename = strrchr(s->filename, '/');
+
+    pos = avio_tell(pb);
+    avio_wb16(pb, 0); /* size */
+
+    /* name */
+    if (filename)
+        filename++;
+    else
+        filename = s->filename;
+    len = strlen(filename);
+
+    avio_w8(pb, MAT_NAME);
+    avio_w8(pb, strlen(SERVER_PATH) + len + 1);
+    avio_write(pb, SERVER_PATH, sizeof(SERVER_PATH) - 1);
+    avio_write(pb, filename, len);
+    avio_w8(pb, 0);
+
+    /* first field */
+    avio_w8(pb, MAT_FIRST_FIELD);
+    avio_w8(pb, 4);
+    avio_wb32(pb, 0);
+
+    /* last field */
+    avio_w8(pb, MAT_LAST_FIELD);
+    avio_w8(pb, 4);
+    avio_wb32(pb, gxf->nb_fields);
+
+    /* reserved */
+    avio_w8(pb, MAT_MARK_IN);
+    avio_w8(pb, 4);
+    avio_wb32(pb, 0);
+
+    avio_w8(pb, MAT_MARK_OUT);
+    avio_w8(pb, 4);
+    avio_wb32(pb, gxf->nb_fields);
+
+    /* estimated size */
+    avio_w8(pb, MAT_SIZE);
+    avio_w8(pb, 4);
+    avio_wb32(pb, avio_size(pb) / 1024);
+
+    return updateSize(pb, pos);
+}
+
+static int gxf_write_track_description_section(AVFormatContext *s)
+{
+    GXFContext *gxf = s->priv_data;
+    AVIOContext *pb = s->pb;
+    int64_t pos;
+    int i;
+
+    pos = avio_tell(pb);
+    avio_wb16(pb, 0); /* size */
+    for (i = 0; i < s->nb_streams; ++i)
+        gxf_write_track_description(s, s->streams[i]->priv_data, i);
+
+    gxf_write_track_description(s, &gxf->timecode_track, s->nb_streams);
+
+    return updateSize(pb, pos);
+}
+
+static int gxf_write_map_packet(AVFormatContext *s, int rewrite)
+{
+    GXFContext *gxf = s->priv_data;
+    AVIOContext *pb = s->pb;
+    int64_t pos = avio_tell(pb);
+
+    if (!rewrite) {
+        if (!(gxf->map_offsets_nb % 30)) {
+            gxf->map_offsets = av_realloc_f(gxf->map_offsets,
+                                            sizeof(*gxf->map_offsets),
+                                            gxf->map_offsets_nb+30);
+            if (!gxf->map_offsets) {
+                av_log(s, AV_LOG_ERROR, "could not realloc map offsets\n");
+                return -1;
+            }
+        }
+        gxf->map_offsets[gxf->map_offsets_nb++] = pos; // do not increment here
+    }
+
+    gxf_write_packet_header(pb, PKT_MAP);
+
+    /* preamble */
+    avio_w8(pb, 0xE0); /* version */
+    avio_w8(pb, 0xFF); /* reserved */
+
+    gxf_write_material_data_section(s);
+    gxf_write_track_description_section(s);
+
+    return updatePacketSize(pb, pos);
+}
+
+static int gxf_write_flt_packet(AVFormatContext *s)
+{
+    GXFContext *gxf = s->priv_data;
+    AVIOContext *pb = s->pb;
+    int64_t pos = avio_tell(pb);
+    int fields_per_flt = (gxf->nb_fields+1) / 1000 + 1;
+    int flt_entries = gxf->nb_fields / fields_per_flt;
+    int i = 0;
+
+    gxf_write_packet_header(pb, PKT_FLT);
+
+    avio_wl32(pb, fields_per_flt); /* number of fields */
+    avio_wl32(pb, flt_entries); /* number of active flt entries */
+
+    if (gxf->flt_entries) {
+        for (i = 0; i < flt_entries; i++)
+            avio_wl32(pb, gxf->flt_entries[(i*fields_per_flt)>>1]);
+    }
+
+    for (; i < 1000; i++)
+        avio_wl32(pb, 0);
+
+    return updatePacketSize(pb, pos);
+}
+
+static int gxf_write_umf_material_description(AVFormatContext *s)
+{
+    GXFContext *gxf = s->priv_data;
+    AVIOContext *pb = s->pb;
+    int timecode_base = gxf->time_base.den == 60000 ? 60 : 50;
+    int64_t timestamp = 0;
+    AVDictionaryEntry *t;
+    uint64_t nb_fields;
+    uint32_t timecode_in; // timecode at mark in
+    uint32_t timecode_out; // timecode at mark out
+
+    if (t = av_dict_get(s->metadata, "creation_time", NULL, 0))
+        timestamp = ff_iso8601_to_unix_time(t->value);
+
+    timecode_in = GXF_TIMECODE(gxf->tc.color, gxf->tc.drop,
+                               gxf->tc.hh, gxf->tc.mm,
+                               gxf->tc.ss, gxf->tc.ff);
+
+    nb_fields = gxf->nb_fields +
+                gxf->tc.hh * (timecode_base * 3600) +
+                gxf->tc.mm * (timecode_base * 60)   +
+                gxf->tc.ss * timecode_base          +
+                gxf->tc.ff;
+
+    timecode_out = GXF_TIMECODE(gxf->tc.color, gxf->tc.drop,
+                                nb_fields / (timecode_base * 3600) % 24,
+                                nb_fields / (timecode_base * 60)   % 60,
+                                nb_fields /  timecode_base % 60,
+                                nb_fields %  timecode_base);
+
+    avio_wl32(pb, gxf->flags);
+    avio_wl32(pb, gxf->nb_fields); /* length of the longest track */
+    avio_wl32(pb, gxf->nb_fields); /* length of the shortest track */
+    avio_wl32(pb, 0); /* mark in */
+    avio_wl32(pb, gxf->nb_fields); /* mark out */
+    avio_wl32(pb, timecode_in); /* timecode mark in */
+    avio_wl32(pb, timecode_out); /* timecode mark out */
+    avio_wl64(pb, timestamp); /* modification time */
+    avio_wl64(pb, timestamp); /* creation time */
+    avio_wl16(pb, 0); /* reserved */
+    avio_wl16(pb, 0); /* reserved */
+    avio_wl16(pb, gxf->audio_tracks);
+    avio_wl16(pb, 1); /* timecode track count */
+    avio_wl16(pb, 0); /* reserved */
+    avio_wl16(pb, gxf->mpeg_tracks);
+    return 48;
+}
+
+static int gxf_write_umf_payload(AVFormatContext *s)
+{
+    GXFContext *gxf = s->priv_data;
+    AVIOContext *pb = s->pb;
+
+    avio_wl32(pb, gxf->umf_length); /* total length of the umf data */
+    avio_wl32(pb, 3); /* version */
+    avio_wl32(pb, s->nb_streams+1);
+    avio_wl32(pb, gxf->umf_track_offset); /* umf track section offset */
+    avio_wl32(pb, gxf->umf_track_size);
+    avio_wl32(pb, s->nb_streams+1);
+    avio_wl32(pb, gxf->umf_media_offset);
+    avio_wl32(pb, gxf->umf_media_size);
+    avio_wl32(pb, gxf->umf_length); /* user data offset */
+    avio_wl32(pb, 0); /* user data size */
+    avio_wl32(pb, 0); /* reserved */
+    avio_wl32(pb, 0); /* reserved */
+    return 48;
+}
+
+static int gxf_write_umf_track_description(AVFormatContext *s)
+{
+    AVIOContext *pb = s->pb;
+    GXFContext *gxf = s->priv_data;
+    int64_t pos = avio_tell(pb);
+    int i;
+
+    gxf->umf_track_offset = pos - gxf->umf_start_offset;
+    for (i = 0; i < s->nb_streams; ++i) {
+        GXFStreamContext *sc = s->streams[i]->priv_data;
+        avio_wl16(pb, sc->media_info);
+        avio_wl16(pb, 1);
+    }
+
+    avio_wl16(pb, gxf->timecode_track.media_info);
+    avio_wl16(pb, 1);
+
+    return avio_tell(pb) - pos;
+}
+
+static int gxf_write_umf_media_mpeg(AVIOContext *pb, AVStream *st)
+{
+    GXFStreamContext *sc = st->priv_data;
+
+    if (st->codec->pix_fmt == AV_PIX_FMT_YUV422P)
+        avio_wl32(pb, 2);
+    else
+        avio_wl32(pb, 1); /* default to 420 */
+    avio_wl32(pb, sc->first_gop_closed == 1); /* closed = 1, open = 0, unknown = 255 */
+    avio_wl32(pb, 3); /* top = 1, bottom = 2, frame = 3, unknown = 0 */
+    avio_wl32(pb, 1); /* I picture per GOP */
+    avio_wl32(pb, sc->p_per_gop);
+    avio_wl32(pb, sc->b_per_i_or_p);
+    if (st->codec->codec_id == AV_CODEC_ID_MPEG2VIDEO)
+        avio_wl32(pb, 2);
+    else if (st->codec->codec_id == AV_CODEC_ID_MPEG1VIDEO)
+        avio_wl32(pb, 1);
+    else
+        avio_wl32(pb, 0);
+    avio_wl32(pb, 0); /* reserved */
+    return 32;
+}
+
+static int gxf_write_umf_media_timecode(AVIOContext *pb, int drop)
+{
+    avio_wl32(pb, drop); /* drop frame */
+    avio_wl32(pb, 0); /* reserved */
+    avio_wl32(pb, 0); /* reserved */
+    avio_wl32(pb, 0); /* reserved */
+    avio_wl32(pb, 0); /* reserved */
+    avio_wl32(pb, 0); /* reserved */
+    avio_wl32(pb, 0); /* reserved */
+    avio_wl32(pb, 0); /* reserved */
+    return 32;
+}
+
+static int gxf_write_umf_media_dv(AVIOContext *pb, GXFStreamContext *sc)
+{
+    int i;
+
+    for (i = 0; i < 8; i++) {
+        avio_wb32(pb, 0);
+    }
+    return 32;
+}
+
+static int gxf_write_umf_media_audio(AVIOContext *pb, GXFStreamContext *sc)
+{
+    avio_wl64(pb, av_double2int(1)); /* sound level to begin to */
+    avio_wl64(pb, av_double2int(1)); /* sound level to begin to */
+    avio_wl32(pb, 0); /* number of fields over which to ramp up sound level */
+    avio_wl32(pb, 0); /* number of fields over which to ramp down sound level */
+    avio_wl32(pb, 0); /* reserved */
+    avio_wl32(pb, 0); /* reserved */
+    return 32;
+}
+
+static int gxf_write_umf_media_description(AVFormatContext *s)
+{
+    GXFContext *gxf = s->priv_data;
+    AVIOContext *pb = s->pb;
+    int64_t pos;
+    int i, j;
+
+    pos = avio_tell(pb);
+    gxf->umf_media_offset = pos - gxf->umf_start_offset;
+    for (i = 0; i <= s->nb_streams; ++i) {
+        GXFStreamContext *sc;
+        int64_t startpos, curpos;
+
+        if (i == s->nb_streams)
+            sc = &gxf->timecode_track;
+        else
+            sc = s->streams[i]->priv_data;
+
+        startpos = avio_tell(pb);
+        avio_wl16(pb, 0); /* length */
+        avio_wl16(pb, sc->media_info);
+        avio_wl16(pb, 0); /* reserved */
+        avio_wl16(pb, 0); /* reserved */
+        avio_wl32(pb, gxf->nb_fields);
+        avio_wl32(pb, 0); /* attributes rw, ro */
+        avio_wl32(pb, 0); /* mark in */
+        avio_wl32(pb, gxf->nb_fields); /* mark out */
+        avio_write(pb, ES_NAME_PATTERN, strlen(ES_NAME_PATTERN));
+        avio_wb16(pb, sc->media_info);
+        for (j = strlen(ES_NAME_PATTERN)+2; j < 88; j++)
+            avio_w8(pb, 0);
+        avio_wl32(pb, sc->track_type);
+        avio_wl32(pb, sc->sample_rate);
+        avio_wl32(pb, sc->sample_size);
+        avio_wl32(pb, 0); /* reserved */
+
+        if (sc == &gxf->timecode_track)
+            gxf_write_umf_media_timecode(pb, gxf->tc.drop);
+        else {
+            AVStream *st = s->streams[i];
+            switch (st->codec->codec_id) {
+            case AV_CODEC_ID_MPEG1VIDEO:
+            case AV_CODEC_ID_MPEG2VIDEO:
+                gxf_write_umf_media_mpeg(pb, st);
+                break;
+            case AV_CODEC_ID_PCM_S16LE:
+                gxf_write_umf_media_audio(pb, sc);
+                break;
+            case AV_CODEC_ID_DVVIDEO:
+                gxf_write_umf_media_dv(pb, sc);
+                break;
+            }
+        }
+
+        curpos = avio_tell(pb);
+        avio_seek(pb, startpos, SEEK_SET);
+        avio_wl16(pb, curpos - startpos);
+        avio_seek(pb, curpos, SEEK_SET);
+    }
+    return avio_tell(pb) - pos;
+}
+
+static int gxf_write_umf_packet(AVFormatContext *s)
+{
+    GXFContext *gxf = s->priv_data;
+    AVIOContext *pb = s->pb;
+    int64_t pos = avio_tell(pb);
+
+    gxf_write_packet_header(pb, PKT_UMF);
+
+    /* preamble */
+    avio_w8(pb, 3); /* first and last (only) packet */
+    avio_wb32(pb, gxf->umf_length); /* data length */
+
+    gxf->umf_start_offset = avio_tell(pb);
+    gxf_write_umf_payload(s);
+    gxf_write_umf_material_description(s);
+    gxf->umf_track_size = gxf_write_umf_track_description(s);
+    gxf->umf_media_size = gxf_write_umf_media_description(s);
+    gxf->umf_length = avio_tell(pb) - gxf->umf_start_offset;
+    return updatePacketSize(pb, pos);
+}
+
+static const int GXF_samples_per_frame[] = { 32768, 0 };
+
+static void gxf_init_timecode_track(GXFStreamContext *sc, GXFStreamContext *vsc)
+{
+    if (!vsc)
+        return;
+
+    sc->media_type = vsc->sample_rate == 60 ? 7 : 8;
+    sc->sample_rate = vsc->sample_rate;
+    sc->media_info = ('T'<<8) | '0';
+    sc->track_type = 3;
+    sc->frame_rate_index = vsc->frame_rate_index;
+    sc->lines_index = vsc->lines_index;
+    sc->sample_size = 16;
+    sc->fields = vsc->fields;
+}
+
+static int gxf_init_timecode(AVFormatContext *s, GXFTimecode *tc, const char *tcstr, int fields)
+{
+    char c;
+
+    if (sscanf(tcstr, "%d:%d:%d%c%d", &tc->hh, &tc->mm, &tc->ss, &c, &tc->ff) != 5) {
+        av_log(s, AV_LOG_ERROR, "unable to parse timecode, "
+                                "syntax: hh:mm:ss[:;.]ff\n");
+        return -1;
+    }
+
+    tc->color = 0;
+    tc->drop = c != ':';
+
+    if (fields == 2)
+        tc->ff = tc->ff * 2;
+
+    return 0;
+}
+
+static int gxf_write_header(AVFormatContext *s)
+{
+    AVIOContext *pb = s->pb;
+    GXFContext *gxf = s->priv_data;
+    GXFStreamContext *vsc = NULL;
+    uint8_t tracks[255] = {0};
+    int i, media_info = 0;
+    AVDictionaryEntry *tcr = av_dict_get(s->metadata, "timecode", NULL, 0);
+
+    if (!pb->seekable) {
+        av_log(s, AV_LOG_ERROR, "gxf muxer does not support streamed output, patch welcome\n");
+        return -1;
+    }
+
+    gxf->flags |= 0x00080000; /* material is simple clip */
+    for (i = 0; i < s->nb_streams; ++i) {
+        AVStream *st = s->streams[i];
+        GXFStreamContext *sc = av_mallocz(sizeof(*sc));
+        if (!sc)
+            return AVERROR(ENOMEM);
+        st->priv_data = sc;
+
+        sc->media_type = ff_codec_get_tag(gxf_media_types, st->codec->codec_id);
+        if (st->codec->codec_type == AVMEDIA_TYPE_AUDIO) {
+            if (st->codec->codec_id != AV_CODEC_ID_PCM_S16LE) {
+                av_log(s, AV_LOG_ERROR, "only 16 BIT PCM LE allowed for now\n");
+                return -1;
+            }
+            if (st->codec->sample_rate != 48000) {
+                av_log(s, AV_LOG_ERROR, "only 48000hz sampling rate is allowed\n");
+                return -1;
+            }
+            if (st->codec->channels != 1) {
+                av_log(s, AV_LOG_ERROR, "only mono tracks are allowed\n");
+                return -1;
+            }
+            sc->track_type = 2;
+            sc->sample_rate = st->codec->sample_rate;
+            avpriv_set_pts_info(st, 64, 1, sc->sample_rate);
+            sc->sample_size = 16;
+            sc->frame_rate_index = -2;
+            sc->lines_index = -2;
+            sc->fields = -2;
+            gxf->audio_tracks++;
+            gxf->flags |= 0x04000000; /* audio is 16 bit pcm */
+            media_info = 'A';
+        } else if (st->codec->codec_type == AVMEDIA_TYPE_VIDEO) {
+            if (i != 0) {
+                av_log(s, AV_LOG_ERROR, "video stream must be the first track\n");
+                return -1;
+            }
+            /* FIXME check from time_base ? */
+            if (st->codec->height == 480 || st->codec->height == 512) { /* NTSC or NTSC+VBI */
+                sc->frame_rate_index = 5;
+                sc->sample_rate = 60;
+                gxf->flags |= 0x00000080;
+                gxf->time_base = (AVRational){ 1001, 60000 };
+            } else if (st->codec->height == 576 || st->codec->height == 608) { /* PAL or PAL+VBI */
+                sc->frame_rate_index = 6;
+                sc->media_type++;
+                sc->sample_rate = 50;
+                gxf->flags |= 0x00000040;
+                gxf->time_base = (AVRational){ 1, 50 };
+            } else {
+                av_log(s, AV_LOG_ERROR, "unsupported video resolution, "
+                       "gxf muxer only accepts PAL or NTSC resolutions currently\n");
+                return -1;
+            }
+            if (!tcr)
+                tcr = av_dict_get(st->metadata, "timecode", NULL, 0);
+            avpriv_set_pts_info(st, 64, gxf->time_base.num, gxf->time_base.den);
+            if (gxf_find_lines_index(st) < 0)
+                sc->lines_index = -1;
+            sc->sample_size = st->codec->bit_rate;
+            sc->fields = 2; /* interlaced */
+
+            vsc = sc;
+
+            switch (st->codec->codec_id) {
+            case AV_CODEC_ID_MJPEG:
+                sc->track_type = 1;
+                gxf->flags |= 0x00004000;
+                media_info = 'J';
+                break;
+            case AV_CODEC_ID_MPEG1VIDEO:
+                sc->track_type = 9;
+                gxf->mpeg_tracks++;
+                media_info = 'L';
+                break;
+            case AV_CODEC_ID_MPEG2VIDEO:
+                sc->first_gop_closed = -1;
+                sc->track_type = 4;
+                gxf->mpeg_tracks++;
+                gxf->flags |= 0x00008000;
+                media_info = 'M';
+                break;
+            case AV_CODEC_ID_DVVIDEO:
+                if (st->codec->pix_fmt == AV_PIX_FMT_YUV422P) {
+                    sc->media_type += 2;
+                    sc->track_type = 6;
+                    gxf->flags |= 0x00002000;
+                    media_info = 'E';
+                } else {
+                    sc->track_type = 5;
+                    gxf->flags |= 0x00001000;
+                    media_info = 'D';
+                }
+                break;
+            default:
+                av_log(s, AV_LOG_ERROR, "video codec not supported\n");
+                return -1;
+            }
+        }
+        /* FIXME first 10 audio tracks are 0 to 9 next 22 are A to V */
+        sc->media_info = media_info<<8 | ('0'+tracks[media_info]++);
+        sc->order = s->nb_streams - st->index;
+    }
+
+    if (ff_audio_interleave_init(s, GXF_samples_per_frame, (AVRational){ 1, 48000 }) < 0)
+        return -1;
+
+    if (tcr && vsc)
+        gxf_init_timecode(s, &gxf->tc, tcr->value, vsc->fields);
+
+    gxf_init_timecode_track(&gxf->timecode_track, vsc);
+    gxf->flags |= 0x200000; // time code track is non-drop frame
+
+    gxf_write_map_packet(s, 0);
+    gxf_write_flt_packet(s);
+    gxf_write_umf_packet(s);
+
+    gxf->packet_count = 3;
+
+    avio_flush(pb);
+    return 0;
+}
+
+static int gxf_write_eos_packet(AVIOContext *pb)
+{
+    int64_t pos = avio_tell(pb);
+
+    gxf_write_packet_header(pb, PKT_EOS);
+    return updatePacketSize(pb, pos);
+}
+
+static int gxf_write_trailer(AVFormatContext *s)
+{
+    GXFContext *gxf = s->priv_data;
+    AVIOContext *pb = s->pb;
+    int64_t end;
+    int i;
+
+    ff_audio_interleave_close(s);
+
+    gxf_write_eos_packet(pb);
+    end = avio_tell(pb);
+    avio_seek(pb, 0, SEEK_SET);
+    /* overwrite map, flt and umf packets with new values */
+    gxf_write_map_packet(s, 1);
+    gxf_write_flt_packet(s);
+    gxf_write_umf_packet(s);
+    avio_flush(pb);
+    /* update duration in all map packets */
+    for (i = 1; i < gxf->map_offsets_nb; i++) {
+        avio_seek(pb, gxf->map_offsets[i], SEEK_SET);
+        gxf_write_map_packet(s, 1);
+        avio_flush(pb);
+    }
+
+    avio_seek(pb, end, SEEK_SET);
+
+    av_freep(&gxf->flt_entries);
+    av_freep(&gxf->map_offsets);
+
+    return 0;
+}
+
+static int gxf_parse_mpeg_frame(GXFStreamContext *sc, const uint8_t *buf, int size)
+{
+    uint32_t c=-1;
+    int i;
+    for(i=0; i<size-4 && c!=0x100; i++){
+        c = (c<<8) + buf[i];
+        if(c == 0x1B8 && sc->first_gop_closed == -1) /* GOP start code */
+            sc->first_gop_closed= (buf[i+4]>>6)&1;
+    }
+    return (buf[i+1]>>3)&7;
+}
+
+static int gxf_write_media_preamble(AVFormatContext *s, AVPacket *pkt, int size)
+{
+    GXFContext *gxf = s->priv_data;
+    AVIOContext *pb = s->pb;
+    AVStream *st = s->streams[pkt->stream_index];
+    GXFStreamContext *sc = st->priv_data;
+    unsigned field_nb;
+    /* If the video is frame-encoded, the frame numbers shall be represented by
+     * even field numbers.
+     * see SMPTE360M-2004  6.4.2.1.3 Media field number */
+    if (st->codec->codec_type == AVMEDIA_TYPE_VIDEO) {
+        field_nb = gxf->nb_fields;
+    } else {
+        field_nb = av_rescale_rnd(pkt->dts, gxf->time_base.den,
+                                  (int64_t)48000*gxf->time_base.num, AV_ROUND_UP);
+    }
+
+    avio_w8(pb, sc->media_type);
+    avio_w8(pb, st->index);
+    avio_wb32(pb, field_nb);
+    if (st->codec->codec_type == AVMEDIA_TYPE_AUDIO) {
+        avio_wb16(pb, 0);
+        avio_wb16(pb, size / 2);
+    } else if (st->codec->codec_id == AV_CODEC_ID_MPEG2VIDEO) {
+        int frame_type = gxf_parse_mpeg_frame(sc, pkt->data, pkt->size);
+        if (frame_type == AV_PICTURE_TYPE_I) {
+            avio_w8(pb, 0x0d);
+            sc->iframes++;
+        } else if (frame_type == AV_PICTURE_TYPE_B) {
+            avio_w8(pb, 0x0f);
+            sc->bframes++;
+        } else {
+            avio_w8(pb, 0x0e);
+            sc->pframes++;
+        }
+        avio_wb24(pb, size);
+    } else if (st->codec->codec_id == AV_CODEC_ID_DVVIDEO) {
+        avio_w8(pb, size / 4096);
+        avio_wb24(pb, 0);
+    } else
+        avio_wb32(pb, size);
+    avio_wb32(pb, field_nb);
+    avio_w8(pb, 1); /* flags */
+    avio_w8(pb, 0); /* reserved */
+    return 16;
+}
+
+static int gxf_write_packet(AVFormatContext *s, AVPacket *pkt)
+{
+    GXFContext *gxf = s->priv_data;
+    AVIOContext *pb = s->pb;
+    AVStream *st = s->streams[pkt->stream_index];
+    int64_t pos = avio_tell(pb);
+    int padding = 0;
+    int packet_start_offset = avio_tell(pb) / 1024;
+
+    gxf_write_packet_header(pb, PKT_MEDIA);
+    if (st->codec->codec_id == AV_CODEC_ID_MPEG2VIDEO && pkt->size % 4) /* MPEG-2 frames must be padded */
+        padding = 4 - pkt->size % 4;
+    else if (st->codec->codec_type == AVMEDIA_TYPE_AUDIO)
+        padding = GXF_AUDIO_PACKET_SIZE - pkt->size;
+    gxf_write_media_preamble(s, pkt, pkt->size + padding);
+    avio_write(pb, pkt->data, pkt->size);
+    gxf_write_padding(pb, padding);
+
+    if (st->codec->codec_type == AVMEDIA_TYPE_VIDEO) {
+        if (!(gxf->flt_entries_nb % 500)) {
+            gxf->flt_entries = av_realloc_f(gxf->flt_entries,
+                                            sizeof(*gxf->flt_entries),
+                                            gxf->flt_entries_nb+500);
+            if (!gxf->flt_entries) {
+                av_log(s, AV_LOG_ERROR, "could not reallocate flt entries\n");
+                return -1;
+            }
+        }
+        gxf->flt_entries[gxf->flt_entries_nb++] = packet_start_offset;
+        gxf->nb_fields += 2; // count fields
+    }
+
+    updatePacketSize(pb, pos);
+
+    gxf->packet_count++;
+    if (gxf->packet_count == 100) {
+        gxf_write_map_packet(s, 0);
+        gxf->packet_count = 0;
+    }
+
+    avio_flush(pb);
+
+    return 0;
+}
+
+static int gxf_compare_field_nb(AVFormatContext *s, AVPacket *next, AVPacket *cur)
+{
+    GXFContext *gxf = s->priv_data;
+    AVPacket *pkt[2] = { cur, next };
+    int i, field_nb[2];
+    GXFStreamContext *sc[2];
+
+    for (i = 0; i < 2; i++) {
+        AVStream *st = s->streams[pkt[i]->stream_index];
+        sc[i] = st->priv_data;
+        if (st->codec->codec_type == AVMEDIA_TYPE_AUDIO) {
+            field_nb[i] = av_rescale_rnd(pkt[i]->dts, gxf->time_base.den,
+                                         (int64_t)48000*gxf->time_base.num, AV_ROUND_UP);
+            field_nb[i] &= ~1; // compare against even field number because audio must be before video
+        } else
+            field_nb[i] = pkt[i]->dts; // dts are field based
+    }
+
+    return field_nb[1] > field_nb[0] ||
+        (field_nb[1] == field_nb[0] && sc[1]->order > sc[0]->order);
+}
+
+static int gxf_interleave_packet(AVFormatContext *s, AVPacket *out, AVPacket *pkt, int flush)
+{
+    if (pkt && s->streams[pkt->stream_index]->codec->codec_type == AVMEDIA_TYPE_VIDEO)
+        pkt->duration = 2; // enforce 2 fields
+    return ff_audio_rechunk_interleave(s, out, pkt, flush,
+                               ff_interleave_packet_per_dts, gxf_compare_field_nb);
+}
+
+AVOutputFormat ff_gxf_muxer = {
+    .name              = "gxf",
+    .long_name         = NULL_IF_CONFIG_SMALL("GXF (General eXchange Format)"),
+    .extensions        = "gxf",
+    .priv_data_size    = sizeof(GXFContext),
+    .audio_codec       = AV_CODEC_ID_PCM_S16LE,
+    .video_codec       = AV_CODEC_ID_MPEG2VIDEO,
+    .write_header      = gxf_write_header,
+    .write_packet      = gxf_write_packet,
+    .write_trailer     = gxf_write_trailer,
+    .interleave_packet = gxf_interleave_packet,
+};