diff --git a/libavformat/nutenc.c b/libavformat/nutenc.c
new file mode 100644
index 0000000000..6cb57f0ed9
--- /dev/null
+++ b/libavformat/nutenc.c
@@ -0,0 +1,353 @@
+/*
+ * nut muxer
+ * Copyright (c) 2004-2007 Michael Niedermayer
+ *
+ * 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 "nut.h"
+
+#define TRACE
+
+static void build_frame_code(AVFormatContext *s){
+    NUTContext *nut = s->priv_data;
+    int key_frame, index, pred, stream_id;
+    int start=1;
+    int end= 254;
+    int keyframe_0_esc= s->nb_streams > 2;
+    int pred_table[10];
+
+    if(keyframe_0_esc){
+        /* keyframe = 0 escape */
+        FrameCode *ft= &nut->frame_code[start];
+        ft->flags= FLAG_STREAM_ID | FLAG_SIZE_MSB | FLAG_CODED_PTS;
+        ft->size_mul=1;
+        start++;
+    }
+
+    for(stream_id= 0; stream_id<s->nb_streams; stream_id++){
+        int start2= start + (end-start)*stream_id / s->nb_streams;
+        int end2  = start + (end-start)*(stream_id+1) / s->nb_streams;
+        AVCodecContext *codec = s->streams[stream_id]->codec;
+        int is_audio= codec->codec_type == CODEC_TYPE_AUDIO;
+        int intra_only= /*codec->intra_only || */is_audio;
+        int pred_count;
+
+        for(key_frame=0; key_frame<2; key_frame++){
+            if(intra_only && keyframe_0_esc && key_frame==0)
+                continue;
+
+            {
+                FrameCode *ft= &nut->frame_code[start2];
+                ft->flags= FLAG_KEY*key_frame;
+                ft->flags|= FLAG_SIZE_MSB | FLAG_CODED_PTS;
+                ft->stream_id= stream_id;
+                ft->size_mul=1;
+                start2++;
+            }
+        }
+
+        key_frame= intra_only;
+#if 1
+        if(is_audio){
+            int frame_bytes= codec->frame_size*(int64_t)codec->bit_rate / (8*codec->sample_rate);
+            int pts;
+            for(pts=0; pts<2; pts++){
+                for(pred=0; pred<2; pred++){
+                    FrameCode *ft= &nut->frame_code[start2];
+                    ft->flags= FLAG_KEY*key_frame;
+                    ft->stream_id= stream_id;
+                    ft->size_mul=frame_bytes + 2;
+                    ft->size_lsb=frame_bytes + pred;
+                    ft->pts_delta=pts;
+                    start2++;
+                }
+            }
+        }else{
+            FrameCode *ft= &nut->frame_code[start2];
+            ft->flags= FLAG_KEY | FLAG_SIZE_MSB;
+            ft->stream_id= stream_id;
+            ft->size_mul=1;
+            ft->pts_delta=1;
+            start2++;
+        }
+#endif
+
+        if(codec->has_b_frames){
+            pred_count=5;
+            pred_table[0]=-2;
+            pred_table[1]=-1;
+            pred_table[2]=1;
+            pred_table[3]=3;
+            pred_table[4]=4;
+        }else if(codec->codec_id == CODEC_ID_VORBIS){
+            pred_count=3;
+            pred_table[0]=2;
+            pred_table[1]=9;
+            pred_table[2]=16;
+        }else{
+            pred_count=1;
+            pred_table[0]=1;
+        }
+
+        for(pred=0; pred<pred_count; pred++){
+            int start3= start2 + (end2-start2)*pred / pred_count;
+            int end3  = start2 + (end2-start2)*(pred+1) / pred_count;
+
+            for(index=start3; index<end3; index++){
+                FrameCode *ft= &nut->frame_code[index];
+                ft->flags= FLAG_KEY*key_frame;
+                ft->flags|= FLAG_SIZE_MSB;
+                ft->stream_id= stream_id;
+//FIXME use single byte size and pred from last
+                ft->size_mul= end3-start3;
+                ft->size_lsb= index - start3;
+                ft->pts_delta= pred_table[pred];
+            }
+        }
+    }
+    memmove(&nut->frame_code['N'+1], &nut->frame_code['N'], sizeof(FrameCode)*(255-'N'));
+    nut->frame_code[  0].flags=
+    nut->frame_code[255].flags=
+    nut->frame_code['N'].flags= FLAG_INVALID;
+}
+
+/**
+ * Gets the length in bytes which is needed to store val as v.
+ */
+static int get_length(uint64_t val){
+    int i=1;
+
+    while(val>>=7)
+        i++;
+
+    return i;
+}
+
+static void put_v(ByteIOContext *bc, uint64_t val){
+    int i= get_length(val);
+
+    while(--i>0)
+        put_byte(bc, 128 | (val>>(7*i)));
+
+    put_byte(bc, val&127);
+}
+
+/**
+ * stores a string as vb.
+ */
+static void put_str(ByteIOContext *bc, const char *string){
+    int len= strlen(string);
+
+    put_v(bc, len);
+    put_buffer(bc, string, len);
+}
+
+static void put_s(ByteIOContext *bc, int64_t val){
+    put_v(bc, 2*FFABS(val) - (val>0));
+}
+
+#ifdef TRACE
+static inline void put_v_trace(ByteIOContext *bc, uint64_t v, char *file, char *func, int line){
+    printf("get_v %5"PRId64" / %"PRIX64" in %s %s:%d\n", v, v, file, func, line);
+
+    put_v(bc, v);
+}
+
+static inline void put_s_trace(ByteIOContext *bc, int64_t v, char *file, char *func, int line){
+    printf("get_s %5"PRId64" / %"PRIX64" in %s %s:%d\n", v, v, file, func, line);
+
+    put_s(bc, v);
+}
+#define put_v(bc, v)  put_v_trace(bc, v, __FILE__, __PRETTY_FUNCTION__, __LINE__)
+#define put_s(bc, v)  put_s_trace(bc, v, __FILE__, __PRETTY_FUNCTION__, __LINE__)
+#endif
+
+static int put_packetheader(NUTContext *nut, ByteIOContext *bc, int max_size, int calculate_checksum){
+    put_flush_packet(bc);
+    nut->packet_start= url_ftell(bc) - 8;
+    nut->written_packet_size = max_size;
+
+    /* packet header */
+    put_v(bc, nut->written_packet_size); /* forward ptr */
+
+    if(calculate_checksum)
+        init_checksum(bc, av_crc04C11DB7_update, 0);
+
+    return 0;
+}
+
+/**
+ *
+ * must not be called more then once per packet
+ */
+static int update_packetheader(NUTContext *nut, ByteIOContext *bc, int additional_size, int calculate_checksum){
+    int64_t start= nut->packet_start;
+    int64_t cur= url_ftell(bc);
+    int size= cur - start - get_length(nut->written_packet_size) - 8;
+
+    if(calculate_checksum)
+        size += 4;
+
+    if(size != nut->written_packet_size){
+        int i;
+
+        assert( size <= nut->written_packet_size );
+
+        url_fseek(bc, start + 8, SEEK_SET);
+        for(i=get_length(size); i < get_length(nut->written_packet_size); i++)
+            put_byte(bc, 128);
+        put_v(bc, size);
+
+        url_fseek(bc, cur, SEEK_SET);
+        nut->written_packet_size= size; //FIXME may fail if multiple updates with differing sizes, as get_length may differ
+
+        if(calculate_checksum)
+            put_le32(bc, get_checksum(bc));
+    }
+
+    return 0;
+}
+
+static int write_header(AVFormatContext *s){
+    NUTContext *nut = s->priv_data;
+    ByteIOContext *bc = &s->pb;
+    AVCodecContext *codec;
+    int i, j, tmp_pts, tmp_flags, tmp_stream, tmp_mul, tmp_size, tmp_fields;
+
+    nut->avf= s;
+
+    nut->stream   = av_mallocz(sizeof(StreamContext)*s->nb_streams);
+    nut->time_base= av_mallocz(sizeof(AVRational   )*s->nb_streams);
+
+    for(i=0; i<s->nb_streams; i++){
+        AVStream *st= s->streams[i];
+        int num, denom, ssize;
+        ff_parse_specific_params(st->codec, &num, &ssize, &denom);
+
+        nut->stream[i].time_base= (AVRational){denom, num};
+
+        av_set_pts_info(st, 64, denom, num);
+
+        for(j=0; j<nut->time_base_count; j++){
+            if(!memcmp(&nut->stream[i].time_base, &nut->time_base[j], sizeof(AVRational))){
+                break;
+            }
+        }
+        nut->time_base[j]= nut->stream[i].time_base;
+        if(j==nut->time_base_count)
+            nut->time_base_count++;
+    }
+//FIXME make nut->stream[i].time_base pointers into nut->time_base
+
+    put_buffer(bc, ID_STRING, strlen(ID_STRING));
+    put_byte(bc, 0);
+
+    /* main header */
+    put_be64(bc, MAIN_STARTCODE);
+    put_packetheader(nut, bc, 120+5*256/*FIXME check*/, 1);
+
+    put_v(bc, 2); /* version */
+    put_v(bc, s->nb_streams);
+    put_v(bc, MAX_DISTANCE);
+    put_v(bc, nut->time_base_count);
+
+    for(i=0; i<nut->time_base_count; i++){
+        put_v(bc, nut->time_base[i].num);
+        put_v(bc, nut->time_base[i].den);
+    }
+
+    build_frame_code(s);
+    assert(nut->frame_code['N'].flags == FLAG_INVALID);
+
+    tmp_pts=0;
+    tmp_mul=1;
+    tmp_stream=0;
+    for(i=0; i<256;){
+        tmp_fields=0;
+        tmp_size=0;
+//        tmp_res=0;
+        if(tmp_pts    != nut->frame_code[i].pts_delta) tmp_fields=1;
+        if(tmp_mul    != nut->frame_code[i].size_mul ) tmp_fields=2;
+        if(tmp_stream != nut->frame_code[i].stream_id) tmp_fields=3;
+        if(tmp_size   != nut->frame_code[i].size_lsb ) tmp_fields=4;
+//        if(tmp_res    != nut->frame_code[i].res            ) tmp_fields=5;
+
+        tmp_pts   = nut->frame_code[i].pts_delta;
+        tmp_flags = nut->frame_code[i].flags;
+        tmp_stream= nut->frame_code[i].stream_id;
+        tmp_mul   = nut->frame_code[i].size_mul;
+        tmp_size  = nut->frame_code[i].size_lsb;
+//        tmp_res   = nut->frame_code[i].res;
+
+        for(j=0; i<256; j++,i++){
+            if(i == 'N'){
+                j--;
+                continue;
+            }
+            if(nut->frame_code[i].pts_delta != tmp_pts   ) break;
+            if(nut->frame_code[i].flags     != tmp_flags ) break;
+            if(nut->frame_code[i].stream_id != tmp_stream) break;
+            if(nut->frame_code[i].size_mul  != tmp_mul   ) break;
+            if(nut->frame_code[i].size_lsb  != tmp_size+j) break;
+//            if(nut->frame_code[i].res       != tmp_res   ) break;
+        }
+        if(j != tmp_mul - tmp_size) tmp_fields=6;
+
+        put_v(bc, tmp_flags);
+        put_v(bc, tmp_fields);
+        if(tmp_fields>0) put_s(bc, tmp_pts);
+        if(tmp_fields>1) put_v(bc, tmp_mul);
+        if(tmp_fields>2) put_v(bc, tmp_stream);
+        if(tmp_fields>3) put_v(bc, tmp_size);
+        if(tmp_fields>4) put_v(bc, 0 /*tmp_res*/);
+        if(tmp_fields>5) put_v(bc, j);
+    }
+
+    update_packetheader(nut, bc, 0, 1);
+
+    put_flush_packet(bc);
+
+    //FIXME stream header, ...
+
+    return 0;
+}
+
+static int write_packet(AVFormatContext *s, AVPacket *pkt){
+    //FIXME
+    return 0;
+}
+
+AVOutputFormat nut_muxer = {
+    "nut",
+    "nut format",
+    "video/x-nut",
+    "nut",
+    sizeof(NUTContext),
+#ifdef CONFIG_LIBVORBIS
+    CODEC_ID_VORBIS,
+#elif defined(CONFIG_LIBMP3LAME)
+    CODEC_ID_MP3,
+#else
+    CODEC_ID_MP2, /* AC3 needs liba52 decoder */
+#endif
+    CODEC_ID_MPEG4,
+    write_header,
+    write_packet,
+//    write_trailer,
+    .flags = AVFMT_GLOBALHEADER,
+};