Replace idiotic (what moron wrote that code?) "buffer overflow" message by
[ffmpeg.git] / libavformat / nut.c
index e4ca17d..546bde1 100644 (file)
 /*
- * "NUT" Container Format muxer and demuxer (DRAFT-200403??)
- * Copyright (c) 2003 Alex Beregszaszi
- * Copyright (c) 2004 Michael Niedermayer
+ * nut
+ * Copyright (c) 2004-2007 Michael Niedermayer
  *
- * This library is free software; you can redistribute it and/or
+ * 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 of the License, or (at your option) any later version.
+ * version 2.1 of the License, or (at your option) any later version.
  *
- * This library is distributed in the hope that it will be useful,
+ * 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 General Public
- * License along with this library; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
- *
- * NUT DRAFT can be found in MPlayer CVS at DOCS/tech/mpcf.txt
- *
- * AND http://people.fsn.hu/~alex/nut/ (TeX, pdf, ps, dvi, ..)
- *
- */
-
-/*
- * TODO:
- * - index writing
- * - index packet reading support
-*/
-
-//#define DEBUG 1
-
-#include <limits.h>
-#include "avformat.h"
-#include "mpegaudio.h"
-#include "avi.h"
-
-#undef NDEBUG
-#include <assert.h>
-
-//#define TRACE
-
-//from /dev/random
-
-#define     MAIN_STARTCODE (0x7A561F5F04ADULL + (((uint64_t)('N'<<8) + 'M')<<48)) 
-#define   STREAM_STARTCODE (0x11405BF2F9DBULL + (((uint64_t)('N'<<8) + 'S')<<48)) 
-#define KEYFRAME_STARTCODE (0xE4ADEECA4569ULL + (((uint64_t)('N'<<8) + 'K')<<48)) 
-#define    INDEX_STARTCODE (0xDD672F23E64EULL + (((uint64_t)('N'<<8) + 'X')<<48)) 
-#define     INFO_STARTCODE (0xAB68B596BA78ULL + (((uint64_t)('N'<<8) + 'I')<<48)) 
-
-#define MAX_DISTANCE (1024*16-1)
-#define MAX_SHORT_DISTANCE (1024*4-1)
-
-#define FLAG_DATA_SIZE       1
-#define FLAG_KEY_FRAME       2
-#define FLAG_INVALID         4
-
-typedef struct {
-    uint8_t flags;
-    uint8_t stream_id_plus1;
-    uint16_t size_mul;
-    uint16_t size_lsb;
-    int16_t timestamp_delta;
-    uint8_t reserved_count;
-} FrameCode;
-
-typedef struct {
-    int last_key_frame;
-    int msb_timestamp_shift;
-    int rate_num;
-    int rate_den;
-    int64_t last_pts;
-    int64_t last_sync_pos;                    ///<pos of last 1/2 type frame
-    int decode_delay;
-} StreamContext;
-
-typedef struct {
-    AVFormatContext *avf;
-    int written_packet_size;
-    int64_t packet_start[3]; //0-> startcode less, 1-> short startcode 2-> long startcodes
-    FrameCode frame_code[256];
-    int stream_count;
-    uint64_t next_startcode;     ///< stores the next startcode if it has alraedy been parsed but the stream isnt seekable
-    StreamContext *stream;
-    int max_distance;
-    int rate_num;
-    int rate_den;
-    int short_startcode;
-} NUTContext;
-
-static char *info_table[][2]={
-       {NULL                   ,  NULL }, // end
-       {NULL                   ,  NULL },
-       {NULL                   , "UTF8"},
-       {NULL                   , "v"},
-       {NULL                   , "s"},
-       {"StreamId"             , "v"},
-       {"SegmentId"            , "v"},
-       {"StartTimestamp"       , "v"},
-       {"EndTimestamp"         , "v"},
-       {"Author"               , "UTF8"},
-       {"Title"                , "UTF8"},
-       {"Description"          , "UTF8"},
-       {"Copyright"            , "UTF8"},
-       {"Encoder"              , "UTF8"},
-       {"Keyword"              , "UTF8"},
-       {"Cover"                , "JPEG"},
-       {"Cover"                , "PNG"},
-};
-
-static void update(NUTContext *nut, int stream_index, int64_t frame_start, int frame_type, int frame_code, int key_frame, int size, int64_t pts){
-    StreamContext *stream= &nut->stream[stream_index];
-    
-    stream->last_key_frame= key_frame;
-    nut->packet_start[ frame_type ]= frame_start;
-    stream->last_pts= pts;
-}
-
-static void reset(AVFormatContext *s, int64_t global_ts){
-    NUTContext *nut = s->priv_data;
-    int i;
-    
-    for(i=0; i<s->nb_streams; i++){
-        StreamContext *stream= &nut->stream[i];
-    
-        stream->last_key_frame= 1;
-
-        stream->last_pts= av_rescale(global_ts, stream->rate_num*(int64_t)nut->rate_den, stream->rate_den*(int64_t)nut->rate_num);
-    }
-}
-
-static void build_frame_code(AVFormatContext *s){
-    NUTContext *nut = s->priv_data;
-    int key_frame, index, pred, stream_id;
-    int start=0;
-    int end= 255;
-    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_DATA_SIZE;
-        ft->stream_id_plus1= 0;
-        ft->size_mul=1;
-        ft->timestamp_delta=0;
-        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_FRAME*key_frame;
-                ft->flags|= FLAG_DATA_SIZE;
-                ft->stream_id_plus1= stream_id + 1;
-                ft->size_mul=1;
-                ft->timestamp_delta=0;
-                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_FRAME*key_frame;
-                    ft->stream_id_plus1= stream_id + 1;
-                    ft->size_mul=frame_bytes + 2;
-                    ft->size_lsb=frame_bytes + pred;
-                    ft->timestamp_delta=pts;
-                    start2++;
-                }
-            }
-        }else{
-            FrameCode *ft= &nut->frame_code[start2];
-            ft->flags= FLAG_KEY_FRAME | FLAG_DATA_SIZE;
-            ft->stream_id_plus1= stream_id + 1;
-            ft->size_mul=1;
-            ft->timestamp_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_FRAME*key_frame;
-                ft->flags|= FLAG_DATA_SIZE;
-                ft->stream_id_plus1= stream_id + 1;
-//FIXME use single byte size and pred from last
-                ft->size_mul= end3-start3;
-                ft->size_lsb= index - start3;
-                ft->timestamp_delta= pred_table[pred];
-            }
-        }
-    }
-    memmove(&nut->frame_code['N'+1], &nut->frame_code['N'], sizeof(FrameCode)*(255-'N'));
-    nut->frame_code['N'].flags= FLAG_INVALID;
-}
-
-static uint64_t get_v(ByteIOContext *bc)
-{
-    uint64_t val = 0;
-
-    for(;;)
-    {
-       int tmp = get_byte(bc);
-
-       if (tmp&0x80)
-           val= (val<<7) + tmp - 0x80;
-       else{
-//av_log(NULL, AV_LOG_DEBUG, "get_v()= %lld\n", (val<<7) + tmp);
-           return (val<<7) + tmp;
-        }
-    }
-    return -1;
-}
-
-static int get_str(ByteIOContext *bc, char *string, int maxlen){
-    int len= get_v(bc);
-    
-    if(len && maxlen)
-        get_buffer(bc, string, FFMIN(len, maxlen));
-    while(len > maxlen){
-        get_byte(bc);
-        len--;
-    }
-
-    if(maxlen)
-        string[FFMIN(len, maxlen-1)]= 0;
-    
-    if(maxlen == len)
-        return -1;
-    else
-        return 0;
-}
-
-static int64_t get_s(ByteIOContext *bc){
-    int64_t v = get_v(bc) + 1;
-
-    if (v&1) return -(v>>1);
-    else     return  (v>>1);
-}
-
-static uint64_t get_vb(ByteIOContext *bc){
-    uint64_t val=0;
-    int i= get_v(bc);
-    
-    if(i>8)
-        return UINT64_MAX;
-    
-    while(i--)
-        val = (val<<8) + get_byte(bc);
-    
-//av_log(NULL, AV_LOG_DEBUG, "get_vb()= %lld\n", val);
-    return val;
-}
-
-#ifdef TRACE
-static inline uint64_t get_v_trace(ByteIOContext *bc, char *file, char *func, int line){
-    uint64_t v= get_v(bc);
-
-    printf("get_v %5lld / %llX in %s %s:%d\n", v, v, file, func, line);
-    return v;
-}
-
-static inline int64_t get_s_trace(ByteIOContext *bc, char *file, char *func, int line){
-    int64_t v= get_s(bc);
-
-    printf("get_s %5lld / %llX in %s %s:%d\n", v, v, file, func, line);
-    return v;
-}
-
-static inline uint64_t get_vb_trace(ByteIOContext *bc, char *file, char *func, int line){
-    uint64_t v= get_vb(bc);
-
-    printf("get_vb %5lld / %llX in %s %s:%d\n", v, v, file, func, line);
-    return v;
-}
-#define get_v(bc)  get_v_trace(bc, __FILE__, __PRETTY_FUNCTION__, __LINE__)
-#define get_s(bc)  get_s_trace(bc, __FILE__, __PRETTY_FUNCTION__, __LINE__)
-#define get_vb(bc)  get_vb_trace(bc, __FILE__, __PRETTY_FUNCTION__, __LINE__)
-#endif
-
-
-static int get_packetheader(NUTContext *nut, ByteIOContext *bc, int calculate_checksum)
-{
-    int64_t start, size;
-    start= url_ftell(bc) - 8;
-
-    init_checksum(bc, calculate_checksum ? update_adler32 : NULL, 0);
-
-    size= get_v(bc);
-
-    nut->packet_start[2] = start;
-    nut->written_packet_size= size;
-
-    return size;
-}
-
-static int check_checksum(ByteIOContext *bc){
-    unsigned long checksum= get_checksum(bc);
-    return checksum != get_be32(bc);
-}
-
-/**
- * 
- */
-static int get_length(uint64_t val){
-    int i;
-
-    for (i=7; val>>i; i+=7);
-
-    return i;
-}
-
-static uint64_t find_any_startcode(ByteIOContext *bc, int64_t pos){
-    uint64_t state=0;
-    
-    if(pos >= 0)
-        url_fseek(bc, pos, SEEK_SET); //note, this may fail if the stream isnt seekable, but that shouldnt matter, as in this case we simply start where we are currently
-
-    while(!url_feof(bc)){
-        state= (state<<8) | get_byte(bc);
-        if((state>>56) != 'N')
-            continue;
-        switch(state){
-        case MAIN_STARTCODE:
-        case STREAM_STARTCODE:
-        case KEYFRAME_STARTCODE:
-        case INFO_STARTCODE:
-        case INDEX_STARTCODE:
-            return state;
-        }
-    }
-
-    return 0;
-}
-
-/**
- * find the given startcode.
- * @param code the startcode
- * @param pos the start position of the search, or -1 if the current position
- * @returns the position of the startcode or -1 if not found
- */
-static int64_t find_startcode(ByteIOContext *bc, uint64_t code, int64_t pos){
-    for(;;){
-        uint64_t startcode= find_any_startcode(bc, pos);
-        if(startcode == code)
-            return url_ftell(bc) - 8;
-        else if(startcode == 0)
-            return -1;
-        pos=-1;
-    }
-}
-
-#ifdef CONFIG_ENCODERS
-
-static void put_v(ByteIOContext *bc, uint64_t val)
-{
-    int i;
-
-//av_log(NULL, AV_LOG_DEBUG, "put_v()= %lld\n", val);
-    val &= 0x7FFFFFFFFFFFFFFFULL; // FIXME can only encode upto 63 bits currently
-    i= get_length(val);
-
-    for (i-=7; i>0; i-=7){
-       put_byte(bc, 0x80 | (val>>i));
-    }
-
-    put_byte(bc, val&0x7f);
-}
-
-/**
- * stores a string as vb.
+ * 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
  */
-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, uint64_t val){
-    if (val<=0) put_v(bc, -2*val  );
-    else        put_v(bc,  2*val-1);
-}
+#include "nut.h"
+#include "tree.h"
 
-static void put_vb(ByteIOContext *bc, uint64_t val){
+void ff_nut_reset_ts(NUTContext *nut, AVRational time_base, int64_t val){
     int i;
-    
-    for (i=8; val>>i; i+=8);
-
-    put_v(bc, i>>3);
-    for(i-=8; i>=0; i-=8)
-        put_byte(bc, (val>>i)&0xFF);
-}
-
-#ifdef TRACE
-static inline void put_v_trace(ByteIOContext *bc, uint64_t v, char *file, char *func, int line){
-    printf("get_v %5lld / %llX 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 %5lld / %llX in %s %s:%d\n", v, v, file, func, line);
-    
-    put_s(bc, v);
-}
-
-static inline void put_vb_trace(ByteIOContext *bc, uint64_t v, char *file, char *func, int line){
-    printf("get_vb %5lld / %llX in %s %s:%d\n", v, v, file, func, line);
-    
-    put_vb(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__)
-#define put_vb(bc, v)  put_vb_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[2]+= nut->written_packet_size;
-    assert(url_ftell(bc) - 8 == nut->packet_start[2]);
-    nut->written_packet_size = max_size;
-    
-    if(calculate_checksum)
-        init_checksum(bc, update_adler32, 0);
-
-    /* packet header */
-    put_v(bc, nut->written_packet_size); /* forward ptr */
-
-    return 0;
-}
-
-static int update_packetheader(NUTContext *nut, ByteIOContext *bc, int additional_size, int calculate_checksum){
-    int64_t start= nut->packet_start[2];
-    int64_t cur= url_ftell(bc);
-    int size= cur - start + additional_size;
-    
-    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+=7)
-            put_byte(bc, 0x80);
-        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_be32(bc, get_checksum(bc));
-    }
-    
-    return 0;
-}
-
-static int nut_write_header(AVFormatContext *s)
-{
-    NUTContext *nut = s->priv_data;
-    ByteIOContext *bc = &s->pb;
-    AVCodecContext *codec;
-    int i, j, tmp_time, tmp_flags,tmp_stream, tmp_mul, tmp_size, tmp_fields;
-
-    nut->avf= s;
-    
-    nut->stream =      
-       av_mallocz(sizeof(StreamContext)*s->nb_streams);
-    
-    av_set_pts_info(s, 60, 1, AV_TIME_BASE);
-    
-    /* main header */
-    put_be64(bc, MAIN_STARTCODE);
-    put_packetheader(nut, bc, 120+5*256, 1);
-    put_v(bc, 2); /* version */
-    put_v(bc, s->nb_streams);
-    put_v(bc, MAX_DISTANCE);
-    
-    put_v(bc, nut->rate_num=1);
-    put_v(bc, nut->rate_den=2);
-    put_v(bc, nut->short_startcode=0x4EFE79);
-    
-    build_frame_code(s);
-    assert(nut->frame_code['N'].flags == FLAG_INVALID);
-    
-    tmp_time= tmp_flags= tmp_stream= tmp_mul= tmp_size= /*tmp_res=*/ INT_MAX;
-    for(i=0; i<256;){
-        tmp_fields=0;
-        tmp_size= 0;
-        if(tmp_time   != nut->frame_code[i].timestamp_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_plus1) 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_time  = nut->frame_code[i].timestamp_delta;
-        tmp_flags = nut->frame_code[i].flags;
-        tmp_stream= nut->frame_code[i].stream_id_plus1;
-        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(nut->frame_code[i].timestamp_delta != tmp_time  ) break;
-            if(nut->frame_code[i].flags           != tmp_flags ) break;
-            if(nut->frame_code[i].stream_id_plus1 != 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_time);
-        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);
-    
-    /* stream headers */
-    for (i = 0; i < s->nb_streams; i++)
-    {
-       int nom, denom, gcd;
-
-       codec = &s->streams[i]->codec;
-       
-       put_be64(bc, STREAM_STARTCODE);
-       put_packetheader(nut, bc, 120 + codec->extradata_size, 1);
-       put_v(bc, i /*s->streams[i]->index*/);
-       put_v(bc, (codec->codec_type == CODEC_TYPE_AUDIO) ? 32 : 0);
-       if (codec->codec_tag)
-           put_vb(bc, codec->codec_tag);
-       else if (codec->codec_type == CODEC_TYPE_VIDEO)
-       {
-           put_vb(bc, codec_get_bmp_tag(codec->codec_id));
-       }
-       else if (codec->codec_type == CODEC_TYPE_AUDIO)
-       {
-           put_vb(bc, codec_get_wav_tag(codec->codec_id));
-       }
-        else
-            put_vb(bc, 0);
-
-       if (codec->codec_type == CODEC_TYPE_VIDEO)
-       {
-           nom = codec->frame_rate;
-           denom = codec->frame_rate_base;
-       }
-       else
-       {
-           nom = codec->sample_rate;
-            if(codec->frame_size>0)
-                denom= codec->frame_size;
-            else
-                denom= 1; //unlucky
-       }
-        gcd= ff_gcd(nom, denom);
-        nom   /= gcd;
-        denom /= gcd;
-        nut->stream[i].rate_num= nom;
-        nut->stream[i].rate_den= denom;
-
-       put_v(bc, codec->bit_rate);
-       put_vb(bc, 0); /* no language code */
-       put_v(bc, nom);
-       put_v(bc, denom);
-        if(nom / denom < 1000)
-           nut->stream[i].msb_timestamp_shift = 7;
-        else
-           nut->stream[i].msb_timestamp_shift = 14;
-       put_v(bc, nut->stream[i].msb_timestamp_shift);
-        put_v(bc, codec->has_b_frames);
-       put_byte(bc, 0); /* flags: 0x1 - fixed_fps, 0x2 - index_present */
-       
-        if(codec->extradata_size){
-            put_v(bc, 1);
-            put_v(bc, codec->extradata_size);
-            put_buffer(bc, codec->extradata, codec->extradata_size);            
-        }
-       put_v(bc, 0); /* end of codec specific headers */
-       
-       switch(codec->codec_type)
-       {
-           case CODEC_TYPE_AUDIO:
-               put_v(bc, codec->sample_rate);
-               put_v(bc, 1);
-               put_v(bc, codec->channels);
-               break;
-           case CODEC_TYPE_VIDEO:
-               put_v(bc, codec->width);
-               put_v(bc, codec->height);
-               put_v(bc, codec->sample_aspect_ratio.num);
-               put_v(bc, codec->sample_aspect_ratio.den);
-               put_v(bc, 0); /* csp type -- unknown */
-               break;
-            default:
-                break;
-       }
-        update_packetheader(nut, bc, 0, 1);
-    }
-
-    /* info header */
-    put_be64(bc, INFO_STARTCODE);
-    put_packetheader(nut, bc, 30+strlen(s->author)+strlen(s->title)+
-        strlen(s->comment)+strlen(s->copyright)+strlen(LIBAVFORMAT_IDENT), 1); 
-    if (s->author[0])
-    {
-        put_v(bc, 9); /* type */
-        put_str(bc, s->author);
-    }
-    if (s->title[0])
-    {
-        put_v(bc, 10); /* type */
-        put_str(bc, s->title);
+    for(i=0; i<nut->avf->nb_streams; i++){
+        nut->stream[i].last_pts= av_rescale_rnd(
+            val / nut->time_base_count,
+            time_base.num * (int64_t)nut->stream[i].time_base->den,
+            time_base.den * (int64_t)nut->stream[i].time_base->num,
+            AV_ROUND_DOWN);
     }
-    if (s->comment[0])
-    {
-        put_v(bc, 11); /* type */
-        put_str(bc, s->comment);
-    }
-    if (s->copyright[0])
-    {
-        put_v(bc, 12); /* type */
-        put_str(bc, s->copyright);
-    }
-    /* encoder */
-    if(!(s->streams[0]->codec.flags & CODEC_FLAG_BITEXACT)){
-        put_v(bc, 13); /* type */
-        put_str(bc, LIBAVFORMAT_IDENT);
-    }
-    
-    put_v(bc, 0); /* eof info */
-    update_packetheader(nut, bc, 0, 1);
-        
-    put_flush_packet(bc);
-    
-    return 0;
 }
 
-static int64_t lsb2full(StreamContext *stream, int64_t lsb){
-    int64_t mask = (1<<stream->msb_timestamp_shift)-1;
+int64_t ff_lsb2full(StreamContext *stream, int64_t lsb){
+    int64_t mask = (1<<stream->msb_pts_shift)-1;
     int64_t delta= stream->last_pts - mask/2;
     return  ((lsb - delta)&mask) + delta;
 }
 
-static int nut_write_packet(AVFormatContext *s, int stream_index, 
-                           const uint8_t *buf, int size, int64_t pts)
-{
-    NUTContext *nut = s->priv_data;
-    StreamContext *stream= &nut->stream[stream_index];
-    ByteIOContext *bc = &s->pb;
-    int key_frame = 0, full_pts=0;
-    AVCodecContext *enc;
-    int64_t coded_pts;
-    int frame_type, best_length, frame_code, flags, i, size_mul, size_lsb, time_delta;
-    const int64_t frame_start= url_ftell(bc);
-
-    if (stream_index > s->nb_streams)
-       return 1;
-        
-    pts= av_rescale(pts, stream->rate_num, stream->rate_den*(int64_t)AV_TIME_BASE);
-
-    enc = &s->streams[stream_index]->codec;
-    key_frame = enc->coded_frame->key_frame;
-    if(enc->coded_frame->pts != AV_NOPTS_VALUE)
-        pts= av_rescale(enc->coded_frame->pts, stream->rate_num, stream->rate_den*(int64_t)AV_TIME_BASE); //FIXME XXX HACK
-    
-    frame_type=0;
-    if(frame_start + size + 20 - FFMAX(nut->packet_start[1], nut->packet_start[2]) > MAX_DISTANCE)
-        frame_type=2;
-    if(key_frame && !stream->last_key_frame)
-        frame_type=2;
-
-    if(frame_type>1){
-        int64_t global_ts= av_rescale(pts, stream->rate_den*(int64_t)nut->rate_num, stream->rate_num*(int64_t)nut->rate_den);
-        reset(s, global_ts);
-       put_be64(bc, KEYFRAME_STARTCODE);
-        put_v(bc, global_ts);
-    }
-    assert(stream->last_pts != AV_NOPTS_VALUE);
-    coded_pts = pts & ((1<<stream->msb_timestamp_shift)-1);
-    if(lsb2full(stream, coded_pts) != pts)
-        full_pts=1;
-
-    if(full_pts)
-        coded_pts= pts + (1<<stream->msb_timestamp_shift);
-
-    best_length=INT_MAX;
-    frame_code= -1;
-    for(i=0; i<256; i++){
-        int stream_id_plus1= nut->frame_code[i].stream_id_plus1;
-        int fc_key_frame;
-        int length=0;
-        size_mul= nut->frame_code[i].size_mul;
-        size_lsb= nut->frame_code[i].size_lsb;
-        time_delta= nut->frame_code[i].timestamp_delta;
-        flags= nut->frame_code[i].flags;
-
-        assert(size_mul > size_lsb);
-        
-        if(stream_id_plus1 == 0) length+= get_length(stream_index);
-        else if(stream_id_plus1 - 1 != stream_index)
-            continue;
-        fc_key_frame= !!(flags & FLAG_KEY_FRAME);
-
-        assert(key_frame==0 || key_frame==1);
-        if(fc_key_frame != key_frame)
-            continue;
-
-        if(flags & FLAG_DATA_SIZE){
-            if(size % size_mul != size_lsb)
-                continue;
-            length += get_length(size / size_mul);
-        }else if(size != size_lsb)
-            continue;
-
-        if(full_pts && time_delta)
-            continue;
-            
-        if(!time_delta){
-            length += get_length(coded_pts);
-        }else{
-            if(time_delta != pts - stream->last_pts)
-                continue;
-        }
-
-        if(length < best_length){
-            best_length= length;
-            frame_code=i;
-        }
-//    av_log(s, AV_LOG_DEBUG, "%d %d %d %d %d %d %d %d %d %d\n", key_frame, frame_type, full_pts, size, stream_index, flags, size_mul, size_lsb, stream_id_plus1, length);
-    }
-
-    assert(frame_code != -1);
-    flags= nut->frame_code[frame_code].flags;
-    size_mul= nut->frame_code[frame_code].size_mul;
-    size_lsb= nut->frame_code[frame_code].size_lsb;
-    time_delta= nut->frame_code[frame_code].timestamp_delta;
-#ifdef TRACE
-    best_length /= 7;
-    best_length ++; //frame_code
-    if(frame_type==2){
-        best_length += 8; // startcode
-    }
-    av_log(s, AV_LOG_DEBUG, "kf:%d ft:%d pt:%d fc:%2X len:%2d size:%d stream:%d flag:%d mul:%d lsb:%d s+1:%d pts_delta:%d pts:%lld fs:%lld\n", key_frame, frame_type, full_pts ? 1 : 0, frame_code, best_length, size, stream_index, flags, size_mul, size_lsb, nut->frame_code[frame_code].stream_id_plus1,(int)(pts - stream->last_pts), pts, frame_start);
-//    av_log(s, AV_LOG_DEBUG, "%d %d %d\n", stream->lru_pts_delta[0], stream->lru_pts_delta[1], stream->lru_pts_delta[2]);
-#endif
-
-    assert(frame_type != 1); //short startcode not implemented yet
-    put_byte(bc, frame_code);
-
-    if(nut->frame_code[frame_code].stream_id_plus1 == 0)
-        put_v(bc, stream_index);
-    if (!time_delta){
-        put_v(bc, coded_pts);
-    }
-    if(flags & FLAG_DATA_SIZE)
-        put_v(bc, size / size_mul);
-    else
-        assert(size == size_lsb);
-    if(size > MAX_DISTANCE){
-        assert(frame_type > 1);
-    }
-    
-    put_buffer(bc, buf, size);
-
-    update(nut, stream_index, frame_start, frame_type, frame_code, key_frame, size, pts);
-    
-    return 0;
-}
-
-static int nut_write_trailer(AVFormatContext *s)
-{
-    NUTContext *nut = s->priv_data;
-    ByteIOContext *bc = &s->pb;
-
-#if 0
-    int i;
-
-    /* WRITE INDEX */
-
-    for (i = 0; s->nb_streams; i++)
-    {
-       put_be64(bc, INDEX_STARTCODE);
-       put_packetheader(nut, bc, 64, 1);
-       put_v(bc, s->streams[i]->id);
-       put_v(bc, ...);
-        update_packetheader(nut, bc, 0, 1);
-    }
-#endif
-
-    put_flush_packet(bc);
-    
-    av_freep(&nut->stream);
-
-    return 0;
-}
-#endif //CONFIG_ENCODERS
-
-static int nut_probe(AVProbeData *p)
-{
-    int i;
-    uint64_t code= 0xff;
-
-    for (i = 0; i < p->buf_size; i++) {
-        code = (code << 8) | p->buf[i];
-        if (code == MAIN_STARTCODE)
-            return AVPROBE_SCORE_MAX;
-    }
-    return 0;
-}
-
-static int decode_main_header(NUTContext *nut){
-    AVFormatContext *s= nut->avf;
-    ByteIOContext *bc = &s->pb;
-    uint64_t tmp;
-    int i, j, tmp_stream, tmp_mul, tmp_time, tmp_size, count, tmp_res;
-    
-    get_packetheader(nut, bc, 1);
-
-    tmp = get_v(bc);
-    if (tmp != 2){
-       av_log(s, AV_LOG_ERROR, "bad version (%Ld)\n", tmp);
-        return -1;
-    }
-    
-    nut->stream_count = get_v(bc);
-    nut->max_distance = get_v(bc);
-    nut->rate_num= get_v(bc);
-    nut->rate_den= get_v(bc);
-    nut->short_startcode= get_v(bc);
-    if(nut->short_startcode>>16 != 'N'){
-       av_log(s, AV_LOG_ERROR, "invalid short startcode %X\n", nut->short_startcode);
-        return -1;
-    }
-    
-    for(i=0; i<256;){
-        int tmp_flags = get_v(bc);
-        int tmp_fields= get_v(bc);
-        if(tmp_fields>0) tmp_time  = get_s(bc);
-        if(tmp_fields>1) tmp_mul   = get_v(bc);
-        if(tmp_fields>2) tmp_stream= get_v(bc);
-        if(tmp_fields>3) tmp_size  = get_v(bc);
-        else             tmp_size  = 0;
-        if(tmp_fields>4) tmp_res   = get_v(bc);
-        else             tmp_res   = 0;
-        if(tmp_fields>5) count     = get_v(bc);
-        else             count     = tmp_mul - tmp_size;
-        
-        while(tmp_fields-- > 6) 
-           get_v(bc);
-        
-        if(count == 0 || i+count > 256){
-            av_log(s, AV_LOG_ERROR, "illegal count %d at %d\n", count, i);
-            return -1;
-        }
-        if(tmp_stream > nut->stream_count + 1){
-            av_log(s, AV_LOG_ERROR, "illegal stream number\n");
-            return -1;
-        }
-
-        for(j=0; j<count; j++,i++){
-            nut->frame_code[i].flags           = tmp_flags ;
-            nut->frame_code[i].timestamp_delta = tmp_time  ;
-            nut->frame_code[i].stream_id_plus1 = tmp_stream;
-            nut->frame_code[i].size_mul        = tmp_mul   ;
-            nut->frame_code[i].size_lsb        = tmp_size+j;
-            nut->frame_code[i].reserved_count  = tmp_res   ;
-        }
-    }
-    if(nut->frame_code['N'].flags != FLAG_INVALID){
-        av_log(s, AV_LOG_ERROR, "illegal frame_code table\n");
-        return -1;
-    }
-
-    if(check_checksum(bc)){
-        av_log(s, AV_LOG_ERROR, "Main header checksum missmatch\n");
-        return -1;
-    }
-
-    return 0;
-}
-
-static int decode_stream_header(NUTContext *nut){
-    AVFormatContext *s= nut->avf;
-    ByteIOContext *bc = &s->pb;
-    int class, nom, denom, stream_id;
-    uint64_t tmp;
-    AVStream *st;
-    
-    get_packetheader(nut, bc, 1);
-    stream_id= get_v(bc);
-    if(stream_id >= nut->stream_count || s->streams[stream_id])
-        return -1;
-    
-    st = av_new_stream(s, stream_id);
-    if (!st)
-        return AVERROR_NOMEM;
-    class = get_v(bc);
-    tmp = get_vb(bc);
-    st->codec.codec_tag= tmp;
-    switch(class)
-    {
-        case 0:
-            st->codec.codec_type = CODEC_TYPE_VIDEO;
-            st->codec.codec_id = codec_get_bmp_id(tmp);
-            if (st->codec.codec_id == CODEC_ID_NONE)
-                av_log(s, AV_LOG_ERROR, "Unknown codec?!\n");
-            break;
-        case 32:
-            st->codec.codec_type = CODEC_TYPE_AUDIO;
-            st->codec.codec_id = codec_get_wav_id(tmp);
-            if (st->codec.codec_id == CODEC_ID_NONE)
-                av_log(s, AV_LOG_ERROR, "Unknown codec?!\n");
-            break;
-        default:
-            av_log(s, AV_LOG_ERROR, "Unknown stream class (%d)\n", class);
-            return -1;
-    }
-    s->bit_rate += get_v(bc);
-    get_vb(bc); /* language code */
-    nom = get_v(bc);
-    denom = get_v(bc);
-    nut->stream[stream_id].msb_timestamp_shift = get_v(bc);
-    nut->stream[stream_id].decode_delay= get_v(bc);
-    get_byte(bc); /* flags */
-
-    /* codec specific data headers */
-    while(get_v(bc) != 0){
-        st->codec.extradata_size= get_v(bc);
-        st->codec.extradata= av_mallocz(st->codec.extradata_size);
-        get_buffer(bc, st->codec.extradata, st->codec.extradata_size);            
-//         url_fskip(bc, get_v(bc));
-    }
-    
-    if (class == 0) /* VIDEO */
-    {
-        st->codec.width = get_v(bc);
-        st->codec.height = get_v(bc);
-        st->codec.sample_aspect_ratio.num= get_v(bc);
-        st->codec.sample_aspect_ratio.den= get_v(bc);
-        get_v(bc); /* csp type */
-
-        st->codec.frame_rate = nom;
-        st->codec.frame_rate_base = denom;
-    }
-    if (class == 32) /* AUDIO */
-    {
-        st->codec.sample_rate = get_v(bc);
-        get_v(bc); // samplerate_den
-        st->codec.channels = get_v(bc);
-    }
-    if(check_checksum(bc)){
-        av_log(s, AV_LOG_ERROR, "Stream header %d checksum missmatch\n", stream_id);
-        return -1;
-    }
-    nut->stream[stream_id].rate_num= nom;
-    nut->stream[stream_id].rate_den= denom;
-    return 0;
-}
-
-static int decode_info_header(NUTContext *nut){
-    AVFormatContext *s= nut->avf;
-    ByteIOContext *bc = &s->pb;
-    
-    get_packetheader(nut, bc, 1);
-
-    for(;;){
-        int id= get_v(bc);
-        char *name, *type, custom_name[256], custom_type[256];
-
-        if(!id)
-            break;
-        else if(id >= sizeof(info_table)/sizeof(info_table[0])){
-            av_log(s, AV_LOG_ERROR, "info id is too large %d %d\n", id, sizeof(info_table)/sizeof(info_table[0]));
-            return -1;
-        }
-
-        type= info_table[id][1];
-        name= info_table[id][0];
-//av_log(s, AV_LOG_DEBUG, "%d %s %s\n", id, type, name);
-
-        if(!type){
-            get_str(bc, custom_type, sizeof(custom_type));
-            type= custom_type;
-        }
-        if(!name){
-            get_str(bc, custom_name, sizeof(custom_name));
-            name= custom_name;
-        }
-        
-        if(!strcmp(type, "v")){
-            int value= get_v(bc);
-        }else{
-            if(!strcmp(name, "Author"))
-                get_str(bc, s->author, sizeof(s->author));
-            else if(!strcmp(name, "Title"))
-                get_str(bc, s->title, sizeof(s->title));
-            else if(!strcmp(name, "Copyright"))
-                get_str(bc, s->copyright, sizeof(s->copyright));
-            else if(!strcmp(name, "Description"))
-                get_str(bc, s->comment, sizeof(s->comment));
-            else
-                get_str(bc, NULL, 0);
-        }
-    }
-    if(check_checksum(bc)){
-        av_log(s, AV_LOG_ERROR, "Info header checksum missmatch\n");
-        return -1;
-    }
-    return 0;
-}
-
-static int nut_read_header(AVFormatContext *s, AVFormatParameters *ap)
-{
-    NUTContext *nut = s->priv_data;
-    ByteIOContext *bc = &s->pb;
-    int64_t pos;
-    int inited_stream_count;
-
-    nut->avf= s;
-    
-    av_set_pts_info(s, 60, 1, AV_TIME_BASE);
-
-    /* main header */
-    pos=0;
-    for(;;){
-        pos= find_startcode(bc, MAIN_STARTCODE, pos)+1;
-        if (pos<0){
-            av_log(s, AV_LOG_ERROR, "no main startcode found\n");
-            return -1;
-        }
-        if(decode_main_header(nut) >= 0)
-            break;
-    }
-    
-    
-    s->bit_rate = 0;
-
-    nut->stream = av_malloc(sizeof(StreamContext)*nut->stream_count);
-
-    /* stream headers */
-    pos=0;
-    for(inited_stream_count=0; inited_stream_count < nut->stream_count;){
-        pos= find_startcode(bc, STREAM_STARTCODE, pos)+1;
-        if (pos<0){
-            av_log(s, AV_LOG_ERROR, "not all stream headers found\n");
-            return -1;
-        }
-        if(decode_stream_header(nut) >= 0)
-            inited_stream_count++;
-    }
-
-    /* info headers */
-    pos=0;
-    for(;;){
-        uint64_t startcode= find_any_startcode(bc, pos);
-        pos= url_ftell(bc);
-
-        if(startcode==0){
-            av_log(s, AV_LOG_ERROR, "EOF before video frames\n");
-            return -1;
-        }else if(startcode == KEYFRAME_STARTCODE){
-            nut->next_startcode= startcode;
-            break;
-        }else if(startcode != INFO_STARTCODE){
-            continue;
-        }
-
-        decode_info_header(nut);
-    }
-
-    return 0;
-}
-
-static int decode_frame_header(NUTContext *nut, int *key_frame_ret, int64_t *pts_ret, int *stream_id_ret, int frame_code, int frame_type, int64_t frame_start){
-    AVFormatContext *s= nut->avf;
-    StreamContext *stream;
-    ByteIOContext *bc = &s->pb;
-    int size, flags, size_mul, size_lsb, stream_id, time_delta;
-    int64_t pts = 0;
-
-    if(frame_type < 2 && frame_start - nut->packet_start[2] > nut->max_distance){
-        av_log(s, AV_LOG_ERROR, "last frame must have been damaged\n");
-        return -1;
-    }
-
-    if(frame_type)
-        nut->packet_start[ frame_type ]= frame_start; //otherwise 1 goto 1 may happen
-    
-    flags= nut->frame_code[frame_code].flags;
-    size_mul= nut->frame_code[frame_code].size_mul;
-    size_lsb= nut->frame_code[frame_code].size_lsb;
-    stream_id= nut->frame_code[frame_code].stream_id_plus1 - 1;
-    time_delta= nut->frame_code[frame_code].timestamp_delta;
-    
-    if(stream_id==-1)
-        stream_id= get_v(bc);
-    if(stream_id >= s->nb_streams){
-        av_log(s, AV_LOG_ERROR, "illegal stream_id\n");
-        return -1;
-    }
-    stream= &nut->stream[stream_id];
-
-//    av_log(s, AV_LOG_DEBUG, "ft:%d ppts:%d %d %d\n", frame_type, stream->lru_pts_delta[0], stream->lru_pts_delta[1], stream->lru_pts_delta[2]);
-
-    *key_frame_ret= !!(flags & FLAG_KEY_FRAME);
-
-    if(!time_delta){
-        int64_t mask = (1<<stream->msb_timestamp_shift)-1;
-        pts= get_v(bc);
-        if(pts > mask){
-            pts -= mask+1;
-        }else{
-            if(stream->last_pts == AV_NOPTS_VALUE){
-                av_log(s, AV_LOG_ERROR, "no reference pts available\n");
-                return -1;
-            }
-            pts= lsb2full(stream, pts);
-        }
-    }else{
-        if(stream->last_pts == AV_NOPTS_VALUE){
-            av_log(s, AV_LOG_ERROR, "no reference pts available\n");
-            return -1;
-        }
-        pts= stream->last_pts + time_delta;
-    }
-
-    if(*key_frame_ret){
-        int64_t av_pts= pts * AV_TIME_BASE * stream->rate_den / stream->rate_num;
-//        av_log(s, AV_LOG_DEBUG, "stream:%d start:%lld pts:%lld length:%lld\n",stream_id, frame_start, av_pts, frame_start - nut->stream[stream_id].last_sync_pos);
-        av_add_index_entry(
-            s->streams[stream_id], 
-            frame_start, 
-            av_pts, 
-            frame_start - nut->stream[stream_id].last_sync_pos,
-            AVINDEX_KEYFRAME);
-        nut->stream[stream_id].last_sync_pos= frame_start;
-//                assert(nut->packet_start == frame_start);
-    }
-
-    assert(size_mul > size_lsb);
-    size= size_lsb;
-    if(flags & FLAG_DATA_SIZE)
-        size+= size_mul*get_v(bc);
-      
-#ifdef TRACE
-av_log(s, AV_LOG_DEBUG, "fs:%lld fc:%d ft:%d kf:%d pts:%lld size:%d mul:%d lsb:%d flags:%d delta:%d\n", frame_start, frame_code, frame_type, *key_frame_ret, pts, size, size_mul, size_lsb, flags, time_delta);
-#endif
-
-    if(frame_type==0 && url_ftell(bc) - nut->packet_start[2] + size > nut->max_distance){
-        av_log(s, AV_LOG_ERROR, "frame size too large\n");
-        return -1;
-    }
-    
-    *stream_id_ret = stream_id;
-    *pts_ret = pts * AV_TIME_BASE * stream->rate_den / stream->rate_num;
-
-    update(nut, stream_id, frame_start, frame_type, frame_code, *key_frame_ret, size, pts);
-
-    return size;
-}
-
-static int decode_frame(NUTContext *nut, AVPacket *pkt, int frame_code, int frame_type, int64_t frame_start){
-    AVFormatContext *s= nut->avf;
-    ByteIOContext *bc = &s->pb;
-    int size, stream_id, key_frame;
-    int64_t pts;
-    
-    size= decode_frame_header(nut, &key_frame, &pts, &stream_id, frame_code, frame_type, frame_start);
-    if(size < 0)
-        return -1;
-
-    av_new_packet(pkt, size);
-    get_buffer(bc, pkt->data, size);
-    pkt->stream_index = stream_id;
-    if (key_frame)
-       pkt->flags |= PKT_FLAG_KEY;
-    pkt->pts = pts;
-
-    return 0;
+int ff_nut_sp_pos_cmp(syncpoint_t *a, syncpoint_t *b){
+    return ((a->pos - b->pos) >> 32) - ((b->pos - a->pos) >> 32);
 }
 
-static int nut_read_packet(AVFormatContext *s, AVPacket *pkt)
-{
-    NUTContext *nut = s->priv_data;
-    ByteIOContext *bc = &s->pb;
-    int i, frame_code=0;
-
-    for(;;){
-        int64_t pos= url_ftell(bc);
-        int frame_type= 0;
-        uint64_t tmp= nut->next_startcode;
-        nut->next_startcode=0;
-
-        if (url_feof(bc))
-            return -1;
-
-        if(tmp){
-            pos-=8;
-        }else{
-            frame_code = get_byte(bc);
-            if(frame_code == 'N'){
-                tmp= frame_code;
-                for(i=1; i<8; i++)
-                    tmp = (tmp<<8) + get_byte(bc);
-            }
-        }
-        switch(tmp){
-        case MAIN_STARTCODE:
-        case STREAM_STARTCODE:
-        case INDEX_STARTCODE:
-            get_packetheader(nut, bc, 0);
-            assert(nut->packet_start[2] == pos);
-            url_fseek(bc, nut->written_packet_size + nut->packet_start[2], SEEK_SET);
-            break;
-        case INFO_STARTCODE:
-            if(decode_info_header(nut)<0)
-                goto resync;
-            break;
-        case KEYFRAME_STARTCODE:
-            frame_type = 2;
-            reset(s, get_v(bc));
-            frame_code = get_byte(bc);
-        case 0:
-            if(decode_frame(nut, pkt, frame_code, frame_type, pos)>=0)
-                return 0;
-        default:
-resync:
-av_log(s, AV_LOG_DEBUG, "syncing from %lld\n", nut->packet_start[2]+1);
-            tmp= find_any_startcode(bc, nut->packet_start[2]+1);
-            if(tmp==0)
-                return -1;
-av_log(s, AV_LOG_DEBUG, "sync\n");
-            nut->next_startcode= tmp;
-        }
-    }
+int ff_nut_sp_pts_cmp(syncpoint_t *a, syncpoint_t *b){
+    return ((a->ts - b->ts) >> 32) - ((b->ts - a->ts) >> 32);
 }
 
-static int64_t nut_read_timestamp(AVFormatContext *s, int stream_index, int64_t *pos_arg, int64_t pos_limit){
-    NUTContext *nut = s->priv_data;
-    StreamContext *stream;
-    ByteIOContext *bc = &s->pb;
-    int64_t pos, pts;
-    uint64_t code;
-    int frame_code,step, stream_id, i,size, key_frame;
-av_log(s, AV_LOG_DEBUG, "read_timestamp(X,%d,%lld,%lld)\n", stream_index, *pos_arg, pos_limit);
-
-    if(*pos_arg < 0)
-        return AV_NOPTS_VALUE;
-
-    pos= *pos_arg;
-    step= FFMIN(16*1024, pos);
-    do{
-        pos-= step;
-        code= find_any_startcode(bc, pos);
-
-        if(code && url_ftell(bc) - 8 <= *pos_arg)
-            break;
-        step= FFMIN(2*step, pos);
-    }while(step);
-
-    if(!code) //nothing found, not even after pos_arg
-        return AV_NOPTS_VALUE;
-
-    url_fseek(bc, -8, SEEK_CUR);
-    for(i=0; i<s->nb_streams; i++)
-        nut->stream[i].last_sync_pos= url_ftell(bc);
-        
-    for(;;){
-        int frame_type=0;
-        int64_t pos= url_ftell(bc);
-        uint64_t tmp=0;
-        
-        if(pos > pos_limit || url_feof(bc))
-            return AV_NOPTS_VALUE;
-
-        frame_code = get_byte(bc);
-        if(frame_code == 'N'){
-            tmp= frame_code;
-            for(i=1; i<8; i++)
-                tmp = (tmp<<8) + get_byte(bc);
-        }
-//av_log(s, AV_LOG_DEBUG, "before switch %llX at=%lld\n", tmp, pos);
-
-        switch(tmp){
-        case MAIN_STARTCODE:
-        case STREAM_STARTCODE:
-        case INDEX_STARTCODE:
-        case INFO_STARTCODE:
-            get_packetheader(nut, bc, 0);
-            assert(nut->packet_start[2]==pos);
-            url_fseek(bc, nut->written_packet_size + pos, SEEK_SET);
-            break;
-        case KEYFRAME_STARTCODE:
-            frame_type=2;
-            reset(s, get_v(bc));
-            frame_code = get_byte(bc);
-        case 0:
-            size= decode_frame_header(nut, &key_frame, &pts, &stream_id, frame_code, frame_type, pos);
-            if(size < 0)
-                goto resync;
-                
-            stream= &nut->stream[stream_id];
-            if(stream_id != stream_index || !key_frame || pos < *pos_arg){
-                url_fseek(bc, size, SEEK_CUR);
-                break;
-            }
-            *pos_arg= pos;
-            return pts;
-        default:
-resync:
-av_log(s, AV_LOG_DEBUG, "syncing from %lld\n", nut->packet_start[2]+1);
-            if(!find_any_startcode(bc, nut->packet_start[2]+1))
-                return AV_NOPTS_VALUE;
+void ff_nut_add_sp(NUTContext *nut, int64_t pos, int64_t back_ptr, int64_t ts){
+    syncpoint_t *sp= av_mallocz(sizeof(syncpoint_t));
+    struct AVTreeNode *node= av_mallocz(av_tree_node_size);
 
-            url_fseek(bc, -8, SEEK_CUR);
-        }
+    sp->pos= pos;
+    sp->back_ptr= back_ptr;
+    sp->ts= ts;
+    av_tree_insert(&nut->syncpoints, sp, ff_nut_sp_pos_cmp, &node);
+    if(node){
+        av_free(sp);
+        av_free(node);
     }
-    return AV_NOPTS_VALUE;
-}
-
-static int nut_read_seek(AVFormatContext *s, int stream_index, int64_t target_ts){
-//    NUTContext *nut = s->priv_data;
-    int64_t pos;
-
-    if(av_seek_frame_binary(s, stream_index, target_ts) < 0)
-        return -1;
-
-    pos= url_ftell(&s->pb);
-    nut_read_timestamp(s, stream_index, &pos, pos-1);
-
-    return 0;
-}
-
-static int nut_read_close(AVFormatContext *s)
-{
-    NUTContext *nut = s->priv_data;
-    int i;
-
-    for(i=0;i<s->nb_streams;i++) {
-        av_freep(&s->streams[i]->codec.extradata);
-    }
-    av_freep(&nut->stream);
-
-    return 0;
-}
-
-static AVInputFormat nut_iformat = {
-    "nut",
-    "nut format",
-    sizeof(NUTContext),
-    nut_probe,
-    nut_read_header,
-    nut_read_packet,
-    nut_read_close,
-    nut_read_seek,
-    nut_read_timestamp,
-    .extensions = "nut",
-};
-
-#ifdef CONFIG_ENCODERS
-static AVOutputFormat nut_oformat = {
-    "nut",
-    "nut format",
-    "video/x-nut",
-    "nut",
-    sizeof(NUTContext),
-#ifdef CONFIG_VORBIS
-    CODEC_ID_VORBIS,
-#elif defined(CONFIG_MP3LAME)
-    CODEC_ID_MP3,
-#else
-    CODEC_ID_MP2, /* AC3 needs liba52 decoder */
-#endif
-    CODEC_ID_MPEG4,
-    nut_write_header,
-    nut_write_packet,
-    nut_write_trailer,
-};
-#endif //CONFIG_ENCODERS
-
-int nut_init(void)
-{
-    av_register_input_format(&nut_iformat);
-#ifdef CONFIG_ENCODERS
-    av_register_output_format(&nut_oformat);
-#endif //CONFIG_ENCODERS
-    return 0;
 }