]> git.sesse.net Git - ffmpeg/blobdiff - libavformat/gxfenc.c
Remove unnecessary header inclusion directives.
[ffmpeg] / libavformat / gxfenc.c
index 9dcbaf264324a8cf5c7e21af424d22683119525c..a6f4b7260efb7d58e46d39524bf8ffa8ab145ba7 100644 (file)
@@ -19,7 +19,6 @@
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  */
 
-#include "libavutil/fifo.h"
 #include "avformat.h"
 #include "gxf.h"
 #include "riff.h"
@@ -43,6 +42,7 @@ typedef struct GXFStreamContext {
     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 {
@@ -56,18 +56,19 @@ typedef struct GXFContext {
     uint32_t umf_length;
     uint16_t umf_track_size;
     uint16_t umf_media_size;
-    int sample_rate;
+    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;
 } GXFContext;
 
-typedef struct GXF_Lines {
-    int height;
-    int index;
-} GXF_Lines;
-
-
-/* FIXME check if it is relevant */
-static const GXF_Lines gxf_lines_tab[] = {
+static const struct {
+    int height, index;
+} gxf_lines_tab[] = {
     { 480,  1 }, /* NTSC */
     { 512,  1 }, /* NTSC + VBI */
     { 576,  2 }, /* PAL */
@@ -92,11 +93,11 @@ static const AVCodecTag gxf_media_types[] = {
     { CODEC_ID_MPEG2VIDEO,  20 }, /* MPEG HD */
     { CODEC_ID_MPEG1VIDEO,  22 }, /* NTSC */
     { CODEC_ID_MPEG1VIDEO,  23 }, /* PAL */
-    { 0, 0 },
+    { CODEC_ID_NONE,         0 },
 };
 
-#define SERVER_PATH "/space/"
-#define ES_NAME_PATTERN "ES."
+#define SERVER_PATH "EXT:/PDR/default/"
+#define ES_NAME_PATTERN "EXT:/PDR/default/ES."
 
 static int gxf_find_lines_index(AVStream *st)
 {
@@ -198,7 +199,6 @@ static int gxf_write_mpeg_auxiliary(ByteIOContext *pb, AVStream *st)
 
 static int gxf_write_timecode_auxiliary(ByteIOContext *pb, GXFStreamContext *sc)
 {
-    /* FIXME implement that */
     put_byte(pb, 0); /* fields */
     put_byte(pb, 0);  /* seconds */
     put_byte(pb, 0); /* minutes */
@@ -208,14 +208,15 @@ static int gxf_write_timecode_auxiliary(ByteIOContext *pb, GXFStreamContext *sc)
     return 8;
 }
 
-static int gxf_write_track_description(ByteIOContext *pb, AVStream *st)
+static int gxf_write_track_description(AVFormatContext *s, GXFStreamContext *sc, int index)
 {
-    GXFStreamContext *sc = st->priv_data;
+    ByteIOContext *pb = s->pb;
     int64_t pos;
+    int mpeg = sc->track_type == 4 || sc->track_type == 9;
 
     /* track description section */
     put_byte(pb, sc->media_type + 0x80);
-    put_byte(pb, st->index + 0xC0);
+    put_byte(pb, index + 0xC0);
 
     pos = url_ftell(pb);
     put_be16(pb, 0); /* size */
@@ -227,11 +228,11 @@ static int gxf_write_track_description(ByteIOContext *pb, AVStream *st)
     put_be16(pb, sc->media_info);
     put_byte(pb, 0);
 
-    if (st->codec->codec_id != CODEC_ID_MPEG2VIDEO) {
+    if (!mpeg) {
         /* auxiliary information */
         put_byte(pb, TRACK_AUX);
         put_byte(pb, 8);
-        if (st->codec->codec_id == CODEC_ID_NONE)
+        if (sc->track_type == 3)
             gxf_write_timecode_auxiliary(pb, sc);
         else
             put_le64(pb, 0);
@@ -242,8 +243,8 @@ static int gxf_write_track_description(ByteIOContext *pb, AVStream *st)
     put_byte(pb, 4);
     put_be32(pb, 0);
 
-    if (st->codec->codec_id == CODEC_ID_MPEG2VIDEO)
-        gxf_write_mpeg_auxiliary(pb, st);
+    if (mpeg)
+        gxf_write_mpeg_auxiliary(pb, s->streams[index]);
 
     /* frame rate */
     put_byte(pb, TRACK_FPS);
@@ -313,6 +314,7 @@ static int gxf_write_material_data_section(AVFormatContext *s)
 
 static int gxf_write_track_description_section(AVFormatContext *s)
 {
+    GXFContext *gxf = s->priv_data;
     ByteIOContext *pb = s->pb;
     int64_t pos;
     int i;
@@ -320,15 +322,31 @@ static int gxf_write_track_description_section(AVFormatContext *s)
     pos = url_ftell(pb);
     put_be16(pb, 0); /* size */
     for (i = 0; i < s->nb_streams; ++i)
-        gxf_write_track_description(pb, s->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)
+static int gxf_write_map_packet(AVFormatContext *s, int rewrite)
 {
+    GXFContext *gxf = s->priv_data;
     ByteIOContext *pb = s->pb;
     int64_t pos = url_ftell(pb);
 
+    if (!rewrite) {
+        if (!(gxf->map_offsets_nb % 30)) {
+            gxf->map_offsets = av_realloc(gxf->map_offsets,
+                                          (gxf->map_offsets_nb+30)*sizeof(*gxf->map_offsets));
+            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 */
@@ -341,37 +359,43 @@ static int gxf_write_map_packet(AVFormatContext *s)
     return updatePacketSize(pb, pos);
 }
 
-#if 0
 static int gxf_write_flt_packet(AVFormatContext *s)
 {
     GXFContext *gxf = s->priv_data;
     ByteIOContext *pb = s->pb;
     int64_t pos = url_ftell(pb);
-    int i;
+    int fields_per_flt = (gxf->nb_fields+1) / 1000 + 1;
+    int flt_entries = gxf->nb_fields / fields_per_flt - 1;
+    int i = 0;
 
     gxf_write_packet_header(pb, PKT_FLT);
 
-    put_le32(pb, 1000); /* number of fields */
-    put_le32(pb, 0); /* number of active flt entries */
+    put_le32(pb, fields_per_flt); /* number of fields */
+    put_le32(pb, flt_entries); /* number of active flt entries */
 
-    for (i = 0; i < 1000; ++i) {
-        put_le32(pb, 0);
+    if (gxf->flt_entries) {
+        for (i = 0; i < flt_entries; i++)
+            put_le32(pb, gxf->flt_entries[(i*fields_per_flt)>>1]);
     }
+
+    for (; i < 1000; i++)
+        put_le32(pb, 0);
+
     return updatePacketSize(pb, pos);
 }
-#endif
 
 static int gxf_write_umf_material_description(AVFormatContext *s)
 {
     GXFContext *gxf = s->priv_data;
     ByteIOContext *pb = s->pb;
+    int timecode_base = gxf->time_base.den == 60000 ? 60 : 50;
 
     // XXX drop frame
     uint32_t timecode =
-        gxf->nb_fields / (gxf->sample_rate * 3600) % 24 << 24 | // hours
-        gxf->nb_fields / (gxf->sample_rate * 60) % 60   << 16 | // minutes
-        gxf->nb_fields / gxf->sample_rate % 60          <<  8 | // seconds
-        gxf->nb_fields % gxf->sample_rate;                    // fields
+        gxf->nb_fields / (timecode_base * 3600) % 24 << 24 | // hours
+        gxf->nb_fields / (timecode_base * 60) % 60   << 16 | // minutes
+        gxf->nb_fields /  timecode_base % 60         <<  8 | // seconds
+        gxf->nb_fields %  timecode_base;                     // fields
 
     put_le32(pb, gxf->flags);
     put_le32(pb, gxf->nb_fields); /* length of the longest track */
@@ -385,7 +409,7 @@ static int gxf_write_umf_material_description(AVFormatContext *s)
     put_le16(pb, 0); /* reserved */
     put_le16(pb, 0); /* reserved */
     put_le16(pb, gxf->audio_tracks);
-    put_le16(pb, 0); /* timecode track count */
+    put_le16(pb, 1); /* timecode track count */
     put_le16(pb, 0); /* reserved */
     put_le16(pb, gxf->mpeg_tracks);
     return 48;
@@ -398,10 +422,10 @@ static int gxf_write_umf_payload(AVFormatContext *s)
 
     put_le32(pb, gxf->umf_length); /* total length of the umf data */
     put_le32(pb, 3); /* version */
-    put_le32(pb, s->nb_streams);
+    put_le32(pb, s->nb_streams+1);
     put_le32(pb, gxf->umf_track_offset); /* umf track section offset */
     put_le32(pb, gxf->umf_track_size);
-    put_le32(pb, s->nb_streams);
+    put_le32(pb, s->nb_streams+1);
     put_le32(pb, gxf->umf_media_offset);
     put_le32(pb, gxf->umf_media_size);
     put_le32(pb, gxf->umf_length); /* user data offset */
@@ -416,29 +440,18 @@ static int gxf_write_umf_track_description(AVFormatContext *s)
     ByteIOContext *pb = s->pb;
     GXFContext *gxf = s->priv_data;
     int64_t pos = url_ftell(pb);
-    int tracks[255]={0};
     int i;
 
     gxf->umf_track_offset = pos - gxf->umf_start_offset;
     for (i = 0; i < s->nb_streams; ++i) {
-        AVStream *st = s->streams[i];
-        GXFStreamContext *sc = st->priv_data;
-        int id = 0;
-
-        switch (st->codec->codec_id) {
-        case CODEC_ID_MPEG1VIDEO: id= 'L'; break;
-        case CODEC_ID_MPEG2VIDEO: id= 'M'; break;
-        case CODEC_ID_PCM_S16LE:  id= 'A'; break;
-        case CODEC_ID_DVVIDEO:    id= sc->track_type == 6 ? 'E' : 'D'; break;
-        case CODEC_ID_MJPEG:      id= 'V'; break;
-        default:                  break;
-        }
-        sc->media_info= id << 8;
-        /* FIXME first 10 audio tracks are 0 to 9 next 22 are A to V */
-        sc->media_info |= '0' + (tracks[id]++);
+        GXFStreamContext *sc = s->streams[i]->priv_data;
         put_le16(pb, sc->media_info);
         put_le16(pb, 1);
     }
+
+    put_le16(pb, gxf->timecode_track.media_info);
+    put_le16(pb, 1);
+
     return url_ftell(pb) - pos;
 }
 
@@ -467,15 +480,14 @@ static int gxf_write_umf_media_mpeg(ByteIOContext *pb, AVStream *st)
 
 static int gxf_write_umf_media_timecode(ByteIOContext *pb, GXFStreamContext *sc)
 {
-    /* FIXME implement */
-    put_be32(pb, 0); /* drop frame flag */
-    put_be32(pb, 0); /* reserved */
-    put_be32(pb, 0); /* reserved */
-    put_be32(pb, 0); /* reserved */
-    put_be32(pb, 0); /* reserved */
-    put_be32(pb, 0); /* reserved */
-    put_be32(pb, 0); /* reserved */
-    put_be32(pb, 0); /* reserved */
+    put_le32(pb, 1); /* non drop frame */
+    put_le32(pb, 0); /* reserved */
+    put_le32(pb, 0); /* reserved */
+    put_le32(pb, 0); /* reserved */
+    put_le32(pb, 0); /* reserved */
+    put_le32(pb, 0); /* reserved */
+    put_le32(pb, 0); /* reserved */
+    put_le32(pb, 0); /* reserved */
     return 32;
 }
 
@@ -516,18 +528,19 @@ static int gxf_write_umf_media_description(AVFormatContext *s)
     GXFContext *gxf = s->priv_data;
     ByteIOContext *pb = s->pb;
     int64_t pos;
-    int i;
+    int i, j;
 
     pos = url_ftell(pb);
     gxf->umf_media_offset = pos - gxf->umf_start_offset;
-    for (i = 0; i < s->nb_streams; ++i) {
-        AVStream *st = s->streams[i];
-        GXFStreamContext *sc = st->priv_data;
-        char buffer[88];
+    for (i = 0; i <= s->nb_streams; ++i) {
+        GXFStreamContext *sc;
         int64_t startpos, curpos;
-        int path_size = strlen(ES_NAME_PATTERN);
 
-        memset(buffer, 0, 88);
+        if (i == s->nb_streams)
+            sc = &gxf->timecode_track;
+        else
+            sc = s->streams[i]->priv_data;
+
         startpos = url_ftell(pb);
         put_le16(pb, 0); /* length */
         put_le16(pb, sc->media_info);
@@ -537,27 +550,32 @@ static int gxf_write_umf_media_description(AVFormatContext *s)
         put_le32(pb, 0); /* attributes rw, ro */
         put_le32(pb, 0); /* mark in */
         put_le32(pb, gxf->nb_fields); /* mark out */
-        strncpy(buffer, ES_NAME_PATTERN, path_size);
-        put_buffer(pb, (uint8_t *)buffer, path_size);
+        put_buffer(pb, ES_NAME_PATTERN, sizeof(ES_NAME_PATTERN));
         put_be16(pb, sc->media_info);
-        put_buffer(pb, (uint8_t *)buffer + path_size + 2, 88 - path_size - 2);
+        for (j = sizeof(ES_NAME_PATTERN)+2; j < 88; j++)
+            put_byte(pb, 0);
         put_le32(pb, sc->track_type);
         put_le32(pb, sc->sample_rate);
         put_le32(pb, sc->sample_size);
         put_le32(pb, 0); /* reserved */
-        switch (st->codec->codec_id) {
-        case CODEC_ID_MPEG2VIDEO:
-            gxf_write_umf_media_mpeg(pb, st);
-            break;
-        case CODEC_ID_PCM_S16LE:
-            gxf_write_umf_media_audio(pb, sc);
-            break;
-        case CODEC_ID_DVVIDEO:
-            gxf_write_umf_media_dv(pb, sc);
-            break;
-        default:
+
+        if (sc == &gxf->timecode_track)
             gxf_write_umf_media_timecode(pb, sc); /* 8 0bytes */
+        else {
+            AVStream *st = s->streams[i];
+            switch (st->codec->codec_id) {
+            case CODEC_ID_MPEG2VIDEO:
+                gxf_write_umf_media_mpeg(pb, st);
+                break;
+            case CODEC_ID_PCM_S16LE:
+                gxf_write_umf_media_audio(pb, sc);
+                break;
+            case CODEC_ID_DVVIDEO:
+                gxf_write_umf_media_dv(pb, sc);
+                break;
+            }
         }
+
         curpos = url_ftell(pb);
         url_fseek(pb, startpos, SEEK_SET);
         put_le16(pb, curpos - startpos);
@@ -589,11 +607,33 @@ static int gxf_write_umf_packet(AVFormatContext *s)
 
 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_write_header(AVFormatContext *s)
 {
     ByteIOContext *pb = s->pb;
     GXFContext *gxf = s->priv_data;
-    int i;
+    GXFStreamContext *vsc = NULL;
+    uint8_t tracks[255] = {0};
+    int i, media_info = 0;
+
+    if (url_is_streamed(pb)) {
+        av_log(s, AV_LOG_ERROR, "gxf muxer does not support streamed output, patch welcome");
+        return -1;
+    }
 
     gxf->flags |= 0x00080000; /* material is simple clip */
     for (i = 0; i < s->nb_streams; ++i) {
@@ -603,8 +643,8 @@ static int gxf_write_header(AVFormatContext *s)
             return AVERROR(ENOMEM);
         st->priv_data = sc;
 
-        sc->media_type = codec_get_tag(gxf_media_types, st->codec->codec_id);
-        if (st->codec->codec_type == CODEC_TYPE_AUDIO) {
+        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 != CODEC_ID_PCM_S16LE) {
                 av_log(s, AV_LOG_ERROR, "only 16 BIT PCM LE allowed for now\n");
                 return -1;
@@ -626,39 +666,61 @@ static int gxf_write_header(AVFormatContext *s)
             sc->fields = -2;
             gxf->audio_tracks++;
             gxf->flags |= 0x04000000; /* audio is 16 bit pcm */
-        } else if (st->codec->codec_type == CODEC_TYPE_VIDEO) {
+            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 { /* assume PAL */
                 sc->frame_rate_index = 6;
                 sc->media_type++;
                 sc->sample_rate = 50;
                 gxf->flags |= 0x00000040;
+                gxf->time_base = (AVRational){ 1, 50 };
             }
-            gxf->sample_rate = sc->sample_rate;
-            av_set_pts_info(st, 64, 1, st->codec->time_base.den);
+            av_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 CODEC_ID_MJPEG:
+                sc->track_type = 1;
+                gxf->flags |= 0x00004000;
+                media_info = 'J';
+                break;
+            case CODEC_ID_MPEG1VIDEO:
+                sc->track_type = 9;
+                gxf->mpeg_tracks++;
+                media_info = 'L';
+                break;
             case CODEC_ID_MPEG2VIDEO:
                 sc->first_gop_closed = -1;
                 sc->track_type = 4;
                 gxf->mpeg_tracks++;
                 gxf->flags |= 0x00008000;
+                media_info = 'M';
                 break;
             case CODEC_ID_DVVIDEO:
                 if (st->codec->pix_fmt == 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:
@@ -666,14 +728,23 @@ static int gxf_write_header(AVFormatContext *s)
                 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;
 
-    gxf_write_map_packet(s);
-    //gxf_write_flt_packet(s);
+    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;
+
     put_flush_packet(pb);
     return 0;
 }
@@ -688,19 +759,33 @@ static int gxf_write_eos_packet(ByteIOContext *pb)
 
 static int gxf_write_trailer(AVFormatContext *s)
 {
+    GXFContext *gxf = s->priv_data;
     ByteIOContext *pb = s->pb;
     int64_t end;
+    int i;
 
     ff_audio_interleave_close(s);
 
     gxf_write_eos_packet(pb);
     end = url_ftell(pb);
     url_fseek(pb, 0, SEEK_SET);
-    /* overwrite map and umf packets with new values */
-    gxf_write_map_packet(s);
-    //gxf_write_flt_packet(s);
+    /* 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);
+    put_flush_packet(pb);
+    /* update duration in all map packets */
+    for (i = 1; i < gxf->map_offsets_nb; i++) {
+        url_fseek(pb, gxf->map_offsets[i], SEEK_SET);
+        gxf_write_map_packet(s, 1);
+        put_flush_packet(pb);
+    }
+
     url_fseek(pb, end, SEEK_SET);
+
+    av_freep(&gxf->flt_entries);
+    av_freep(&gxf->map_offsets);
+
     return 0;
 }
 
@@ -726,16 +811,17 @@ static int gxf_write_media_preamble(AVFormatContext *s, AVPacket *pkt, int size)
     /* 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 == CODEC_TYPE_VIDEO) {
+    if (st->codec->codec_type == AVMEDIA_TYPE_VIDEO) {
         field_nb = gxf->nb_fields;
     } else {
-        field_nb = av_rescale_rnd(pkt->dts, gxf->sample_rate, st->codec->time_base.den, AV_ROUND_UP);
+        field_nb = av_rescale_rnd(pkt->dts, gxf->time_base.den,
+                                  (int64_t)48000*gxf->time_base.num, AV_ROUND_UP);
     }
 
     put_byte(pb, sc->media_type);
     put_byte(pb, st->index);
     put_be32(pb, field_nb);
-    if (st->codec->codec_type == CODEC_TYPE_AUDIO) {
+    if (st->codec->codec_type == AVMEDIA_TYPE_AUDIO) {
         put_be16(pb, 0);
         put_be16(pb, size / 2);
     } else if (st->codec->codec_id == CODEC_ID_MPEG2VIDEO) {
@@ -773,24 +859,66 @@ static int gxf_write_packet(AVFormatContext *s, AVPacket *pkt)
     gxf_write_packet_header(pb, PKT_MEDIA);
     if (st->codec->codec_id == CODEC_ID_MPEG2VIDEO && pkt->size % 4) /* MPEG-2 frames must be padded */
         padding = 4 - pkt->size % 4;
-    else if (st->codec->codec_type == CODEC_TYPE_AUDIO)
+    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);
     put_buffer(pb, pkt->data, pkt->size);
     gxf_write_padding(pb, padding);
 
-    if (st->codec->codec_type == CODEC_TYPE_VIDEO)
+    if (st->codec->codec_type == AVMEDIA_TYPE_VIDEO) {
+        if (!(gxf->flt_entries_nb % 500)) {
+            gxf->flt_entries = av_realloc(gxf->flt_entries,
+                                          (gxf->flt_entries_nb+500)*sizeof(*gxf->flt_entries));
+            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++] = url_ftell(pb) / 1024;
         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;
+    }
 
     put_flush_packet(pb);
 
-    return updatePacketSize(pb, pos);
+    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,
-                               av_interleave_packet_per_dts, ff_interleave_compare_dts);
+                               av_interleave_packet_per_dts, gxf_compare_field_nb);
 }
 
 AVOutputFormat gxf_muxer = {