diff --git a/libavformat/mxfenc.c b/libavformat/mxfenc.c
index d8678c9..7fce7b9 100644
--- a/libavformat/mxfenc.c
+++ b/libavformat/mxfenc.c
@@ -60,12 +60,13 @@
 #include "mxf.h"
 #include "config.h"
 
-extern AVOutputFormat ff_mxf_d10_muxer;
-extern AVOutputFormat ff_mxf_opatom_muxer;
-
 #define EDIT_UNITS_PER_BODY 250
 #define KAG_SIZE 512
 
+#define MODE_OP1a 0x01
+#define MODE_D10  0x02
+#define MODE_OPA  0x04
+
 typedef struct MXFIndexEntry {
     uint64_t offset;
     unsigned slice_offset; ///< offset of audio slice
@@ -258,6 +259,7 @@ typedef struct MXFContext {
     int store_user_comments;
     int track_instance_count; // used to generate MXFTrack uuids
     int cbr_index;           ///< use a constant bitrate index
+    int mode;
 } MXFContext;
 
 static const uint8_t uuid_base[]            = { 0xAD,0xAB,0x44,0x24,0x2f,0x25,0x4d,0xc7,0x92,0xff,0x29,0xbd };
@@ -630,7 +632,7 @@ static void mxf_write_preface(AVFormatContext *s)
 
     // operational pattern
     mxf_write_local_tag(pb, 16, 0x3B09);
-    if (s->oformat == &ff_mxf_opatom_muxer)
+    if (mxf->mode == MODE_OPA)
         avio_write(pb, opatom_ul, 16);
     else
         avio_write(pb, op1a_ul, 16);
@@ -723,7 +725,7 @@ static void mxf_write_identification(AVFormatContext *s)
     MXFContext *mxf = s->priv_data;
     AVIOContext *pb = s->pb;
     const char *company = "FFmpeg";
-    const char *product = s->oformat != &ff_mxf_opatom_muxer ? "OP1a Muxer" : "OPAtom Muxer";
+    const char *product = mxf->mode != MODE_OPA ? "OP1a Muxer" : "OPAtom Muxer";
     const char *version;
     int length;
 
@@ -821,7 +823,7 @@ static void mxf_write_track(AVFormatContext *s, AVStream *st, MXFPackage *packag
     // write edit rate
     mxf_write_local_tag(pb, 8, 0x4B01);
 
-    if (st == mxf->timecode_track && s->oformat == &ff_mxf_opatom_muxer) {
+    if (st == mxf->timecode_track && mxf->mode == MODE_OPA) {
         avio_wb32(pb, mxf->tc.rate.num);
         avio_wb32(pb, mxf->tc.rate.den);
     } else {
@@ -857,7 +859,7 @@ static void mxf_write_common_fields(AVFormatContext *s, AVStream *st)
     // write duration
     mxf_write_local_tag(pb, 8, 0x0202);
 
-    if (st != mxf->timecode_track && s->oformat == &ff_mxf_opatom_muxer && st->codecpar->codec_type == AVMEDIA_TYPE_AUDIO) {
+    if (st != mxf->timecode_track && mxf->mode == MODE_OPA && st->codecpar->codec_type == AVMEDIA_TYPE_AUDIO) {
         avio_wb64(pb, mxf->body_offset / mxf->edit_unit_byte_count);
     } else {
         avio_wb64(pb, mxf->duration);
@@ -1023,7 +1025,7 @@ static int64_t mxf_write_generic_desc(AVFormatContext *s, AVStream *st, const UI
     avio_wb32(pb, st->index+2);
 
     mxf_write_local_tag(pb, 8, 0x3001);
-    if (s->oformat == &ff_mxf_d10_muxer) {
+    if (mxf->mode == MODE_D10) {
         avio_wb32(pb, mxf->time_base.den);
         avio_wb32(pb, mxf->time_base.num);
     } else {
@@ -1064,6 +1066,7 @@ static inline uint32_t rescale_mastering_luma(AVRational q)
 
 static int64_t mxf_write_cdci_common(AVFormatContext *s, AVStream *st, const UID key)
 {
+    MXFContext *mxf = s->priv_data;
     MXFStreamContext *sc = st->priv_data;
     AVIOContext *pb = s->pb;
     int stored_width = 0;
@@ -1095,7 +1098,7 @@ static int64_t mxf_write_cdci_common(AVFormatContext *s, AVStream *st, const UID
     mxf_write_local_tag(pb, 4, 0x3202);
     avio_wb32(pb, stored_height>>sc->interlaced);
 
-    if (s->oformat == &ff_mxf_d10_muxer) {
+    if (mxf->mode == MODE_D10) {
         //Stored F2 Offset
         mxf_write_local_tag(pb, 4, 0x3216);
         avio_wb32(pb, 0);
@@ -1392,7 +1395,7 @@ static int64_t mxf_write_generic_sound_common(AVFormatContext *s, AVStream *st,
     int show_warnings = !mxf->footer_partition_offset;
     int64_t pos = mxf_write_generic_desc(s, st, key);
 
-    if (s->oformat == &ff_mxf_opatom_muxer) {
+    if (mxf->mode == MODE_OPA) {
         mxf_write_local_tag(pb, 8, 0x3002);
         avio_wb64(pb, mxf->body_offset / mxf->edit_unit_byte_count);
     }
@@ -1406,17 +1409,17 @@ static int64_t mxf_write_generic_sound_common(AVFormatContext *s, AVStream *st,
     avio_wb32(pb, st->codecpar->sample_rate);
     avio_wb32(pb, 1);
 
-    if (s->oformat == &ff_mxf_d10_muxer) {
+    if (mxf->mode == MODE_D10) {
         mxf_write_local_tag(pb, 1, 0x3D04);
         avio_w8(pb, 0);
     }
 
     mxf_write_local_tag(pb, 4, 0x3D07);
     if (mxf->channel_count == -1) {
-        if (show_warnings && (s->oformat == &ff_mxf_d10_muxer) && (st->codecpar->channels != 4) && (st->codecpar->channels != 8))
+        if (show_warnings && (mxf->mode == MODE_D10) && (st->codecpar->channels != 4) && (st->codecpar->channels != 8))
             av_log(s, AV_LOG_WARNING, "the number of audio channels shall be 4 or 8 : the output will not comply to MXF D-10 specs, use -d10_channelcount to fix this\n");
         avio_wb32(pb, st->codecpar->channels);
-    } else if (s->oformat == &ff_mxf_d10_muxer) {
+    } else if (mxf->mode == MODE_D10) {
         if (show_warnings && (mxf->channel_count < st->codecpar->channels))
             av_log(s, AV_LOG_WARNING, "d10_channelcount < actual number of audio channels : some channels will be discarded\n");
         if (show_warnings && (mxf->channel_count != 4) && (mxf->channel_count != 8))
@@ -1916,7 +1919,7 @@ static int mxf_write_partition(AVFormatContext *s, int bodysid,
     avio_wb32(pb, index_byte_count ? indexsid : 0); // indexSID
 
     // BodyOffset
-    if (bodysid && mxf->edit_units_count && mxf->body_partitions_count && s->oformat != &ff_mxf_opatom_muxer)
+    if (bodysid && mxf->edit_units_count && mxf->body_partitions_count && mxf->mode != MODE_OPA)
         avio_wb64(pb, mxf->body_offset);
     else
         avio_wb64(pb, 0);
@@ -1924,7 +1927,7 @@ static int mxf_write_partition(AVFormatContext *s, int bodysid,
     avio_wb32(pb, bodysid); // bodySID
 
     // operational pattern
-    if (s->oformat == &ff_mxf_opatom_muxer)
+    if (mxf->mode == MODE_OPA)
         avio_write(pb, opatom_ul, 16);
     else
         avio_write(pb, op1a_ul, 16);
@@ -2343,6 +2346,7 @@ static const UID *mxf_get_mpeg2_codec_ul(AVCodecParameters *par)
 static int mxf_parse_mpeg2_frame(AVFormatContext *s, AVStream *st,
                                  AVPacket *pkt, MXFIndexEntry *e)
 {
+    MXFContext *mxf = s->priv_data;
     MXFStreamContext *sc = st->priv_data;
     uint32_t c = -1;
     int i;
@@ -2399,7 +2403,7 @@ static int mxf_parse_mpeg2_frame(AVFormatContext *s, AVStream *st,
             }
         }
     }
-    if (s->oformat != &ff_mxf_d10_muxer)
+    if (mxf->mode != MODE_D10)
         sc->codec_ul = mxf_get_mpeg2_codec_ul(st->codecpar);
     return !!sc->codec_ul;
 }
@@ -2466,7 +2470,7 @@ static int mxf_write_header(AVFormatContext *s)
     if (!s->nb_streams)
         return -1;
 
-    if (s->oformat == &ff_mxf_opatom_muxer && s->nb_streams !=1) {
+    if (mxf->mode == MODE_OPA && s->nb_streams !=1) {
         av_log(s, AV_LOG_ERROR, "there must be exactly one stream for mxf opatom\n");
         return -1;
     }
@@ -2474,6 +2478,13 @@ static int mxf_write_header(AVFormatContext *s)
     if (!av_dict_get(s->metadata, "comment_", NULL, AV_DICT_IGNORE_SUFFIX))
         mxf->store_user_comments = 0;
 
+    mxf->mode = MODE_OP1a;
+    if (s->oformat) {
+        if (!strcmp("mxf", s->oformat->name)) mxf->mode = MODE_OP1a;
+        else if (!strcmp("mxf_d10",s->oformat->name)) mxf->mode = MODE_D10;
+        else if (!strcmp("mxf_opatom", s->oformat->name)) mxf->mode = MODE_OPA;
+    }
+
     for (i = 0; i < s->nb_streams; i++) {
         AVStream *st = s->streams[i];
         MXFStreamContext *sc = av_mallocz(sizeof(*sc));
@@ -2482,7 +2493,7 @@ static int mxf_write_header(AVFormatContext *s)
         st->priv_data = sc;
         sc->index = -1;
 
-        if (((i == 0) ^ (st->codecpar->codec_type == AVMEDIA_TYPE_VIDEO)) && s->oformat != &ff_mxf_opatom_muxer) {
+        if (((i == 0) ^ (st->codecpar->codec_type == AVMEDIA_TYPE_VIDEO)) && mxf->mode != MODE_OPA) {
             av_log(s, AV_LOG_ERROR, "there must be exactly one video stream and it must be the first one\n");
             return -1;
         }
@@ -2526,12 +2537,12 @@ static int mxf_write_header(AVFormatContext *s)
 
             sc->video_bit_rate = st->codecpar->bit_rate;
 
-            if (s->oformat == &ff_mxf_d10_muxer ||
+            if (mxf->mode == MODE_D10 ||
                 st->codecpar->codec_id == AV_CODEC_ID_DNXHD ||
                 st->codecpar->codec_id == AV_CODEC_ID_DVVIDEO)
                 mxf->cbr_index = 1;
 
-            if (s->oformat == &ff_mxf_d10_muxer) {
+            if (mxf->mode == MODE_D10) {
                 int ntsc = mxf->time_base.den != 25;
                 int ul_index;
 
@@ -2569,7 +2580,7 @@ static int mxf_write_header(AVFormatContext *s)
                 return -1;
             }
             avpriv_set_pts_info(st, 64, 1, st->codecpar->sample_rate);
-            if (s->oformat == &ff_mxf_d10_muxer) {
+            if (mxf->mode == MODE_D10) {
                 if (st->index != 1) {
                     av_log(s, AV_LOG_ERROR, "MXF D-10 only support one audio track\n");
                     return -1;
@@ -2581,7 +2592,7 @@ static int mxf_write_header(AVFormatContext *s)
                 sc->index = INDEX_D10_AUDIO;
                 sc->container_ul = ((MXFStreamContext*)s->streams[0]->priv_data)->container_ul;
                 sc->frame_size = 4 + 8 * av_rescale_rnd(st->codecpar->sample_rate, mxf->time_base.num, mxf->time_base.den, AV_ROUND_UP) * 4;
-            } else if (s->oformat == &ff_mxf_opatom_muxer) {
+            } else if (mxf->mode == MODE_OPA) {
                 AVRational tbc = av_inv_q(mxf->audio_edit_rate);
 
                 if (st->codecpar->codec_id != AV_CODEC_ID_PCM_S16LE &&
@@ -2647,7 +2658,7 @@ static int mxf_write_header(AVFormatContext *s)
         present[sc->index]++;
     }
 
-    if (s->oformat == &ff_mxf_d10_muxer || s->oformat == &ff_mxf_opatom_muxer) {
+    if (mxf->mode == MODE_D10 || mxf->mode == MODE_OPA) {
         mxf->essence_container_count = 1;
     }
 
@@ -2818,7 +2829,7 @@ static void mxf_compute_edit_unit_byte_count(AVFormatContext *s)
     MXFContext *mxf = s->priv_data;
     int i;
 
-    if (s->oformat == &ff_mxf_opatom_muxer) {
+    if (mxf->mode == MODE_OPA) {
         MXFStreamContext *sc = s->streams[0]->priv_data;
         mxf->edit_unit_byte_count = sc->frame_size;
         return;
@@ -2889,7 +2900,7 @@ static int mxf_write_packet(AVFormatContext *s, AVPacket *pkt)
             mxf_compute_edit_unit_byte_count(s);
     }
 
-    if (s->oformat == &ff_mxf_opatom_muxer)
+    if (mxf->mode == MODE_OPA)
         return mxf_write_opatom_packet(s, pkt, &ie);
 
     if (!mxf->header_written) {
@@ -2937,7 +2948,7 @@ static int mxf_write_packet(AVFormatContext *s, AVPacket *pkt)
 
     mxf_write_klv_fill(s);
     avio_write(pb, sc->track_essence_element_key, 16); // write key
-    if (s->oformat == &ff_mxf_d10_muxer &&
+    if (mxf->mode == MODE_D10 &&
         st->codecpar->codec_type == AVMEDIA_TYPE_AUDIO) {
         mxf_write_d10_audio_packet(s, st, pkt);
     } else {
@@ -2959,7 +2970,7 @@ static void mxf_write_random_index_pack(AVFormatContext *s)
     avio_write(pb, random_index_pack_key, 16);
     klv_encode_ber_length(pb, 28 + 12LL*mxf->body_partitions_count);
 
-    if (mxf->edit_unit_byte_count && s->oformat != &ff_mxf_opatom_muxer)
+    if (mxf->edit_unit_byte_count && mxf->mode != MODE_OPA)
         avio_wb32(pb, 1); // BodySID of header partition
     else
         avio_wb32(pb, 0);
@@ -2983,7 +2994,7 @@ static int mxf_write_footer(AVFormatContext *s)
     int i, err;
 
     if (!mxf->header_written ||
-        (s->oformat == &ff_mxf_opatom_muxer && !mxf->body_partition_offset)) {
+        (mxf->mode == MODE_OPA && !mxf->body_partition_offset)) {
         /* reason could be invalid options/not supported codec/out of memory */
         return AVERROR_UNKNOWN;
     }
@@ -2992,7 +3003,7 @@ static int mxf_write_footer(AVFormatContext *s)
 
     mxf_write_klv_fill(s);
     mxf->footer_partition_offset = avio_tell(pb);
-    if (mxf->edit_unit_byte_count && s->oformat != &ff_mxf_opatom_muxer) { // no need to repeat index
+    if (mxf->edit_unit_byte_count && mxf->mode != MODE_OPA) { // no need to repeat index
         if ((err = mxf_write_partition(s, 0, 0, footer_partition_key, 0)) < 0)
             return err;
     } else {
@@ -3006,7 +3017,7 @@ static int mxf_write_footer(AVFormatContext *s)
     mxf_write_random_index_pack(s);
 
     if (s->pb->seekable & AVIO_SEEKABLE_NORMAL) {
-        if (s->oformat == &ff_mxf_opatom_muxer) {
+        if (mxf->mode == MODE_OPA) {
             /* rewrite body partition to update lengths */
             avio_seek(pb, mxf->body_partition_offset[0], SEEK_SET);
             if ((err = mxf_write_opatom_body_partition(s)) < 0)
@@ -3014,7 +3025,7 @@ static int mxf_write_footer(AVFormatContext *s)
         }
 
         avio_seek(pb, 0, SEEK_SET);
-        if (mxf->edit_unit_byte_count && s->oformat != &ff_mxf_opatom_muxer) {
+        if (mxf->edit_unit_byte_count && mxf->mode != MODE_OPA) {
             if ((err = mxf_write_partition(s, 1, 2, header_closed_partition_key, 1)) < 0)
                 return err;
             mxf_write_klv_fill(s);
