Start working on a branch where FFmpeg is not copied, patched and carved to be built with automake but instead imported inline and built using its own build system. This is an import of a slightly modified FFmpeg current tree. xine-lib builds, install and run fine with it, but there are of course plenty of things that needs to be fixed before it can even be considered for a 1.2.x series. Work will continue in the next days of course.

CVS patchset: 8397
CVS date: 2006/12/02 01:19:48

1 files changed, 889 insertions, 0 deletions

diff --git a/contrib/ffmpeg/libavformat/nutdec.c b/contrib/ffmpeg/libavformat/nutdec.c
new file mode 100644
index 000000000..7e0f8cd93
--- /dev/null
+++ b/contrib/ffmpeg/libavformat/nutdec.c
@@ -0,0 +1,889 @@
+/*
+ * "NUT" Container Format demuxer
+ * Copyright (c) 2004-2006 Michael Niedermayer
+ * Copyright (c) 2003 Alex Beregszaszi
+ *
+ * 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 "tree.h"
+#include "nut.h"
+
+#undef NDEBUG
+#include <assert.h>
+
+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{
+            return (val<<7) + tmp;
+        }
+    }
+    return -1;
+}
+
+static int get_str(ByteIOContext *bc, char *string, unsigned int maxlen){
+    unsigned 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_fourcc(ByteIOContext *bc){
+    unsigned int len= get_v(bc);
+
+    if     (len==2) return get_le16(bc);
+    else if(len==4) return get_le32(bc);
+    else            return -1;
+}
+
+#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 %5"PRId64" / %"PRIX64" 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 %5"PRId64" / %"PRIX64" 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 %5"PRId64" / %"PRIX64" 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;
+
+    size= get_v(bc);
+
+    init_checksum(bc, calculate_checksum ? av_crc04C11DB7_update : NULL, 0);
+
+//    nut->packet_start[2] = start;
+//    nut->written_packet_size= size;
+
+    return size;
+}
+
+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 SYNCPOINT_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;
+    }
+}
+
+static int64_t 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_probe(AVProbeData *p){
+    int i;
+    uint64_t code= 0;
+
+    for (i = 0; i < p->buf_size; i++) {
+        code = (code << 8) | p->buf[i];
+        if (code == MAIN_STARTCODE)
+            return AVPROBE_SCORE_MAX;
+    }
+    return 0;
+}
+
+#define GET_V(dst, check) \
+    tmp= get_v(bc);\
+    if(!(check)){\
+        av_log(s, AV_LOG_ERROR, "Error " #dst " is (%"PRId64")\n", tmp);\
+        return -1;\
+    }\
+    dst= tmp;
+
+static int skip_reserved(ByteIOContext *bc, int64_t pos){
+    pos -= url_ftell(bc);
+    if(pos<0){
+        url_fseek(bc, pos, SEEK_CUR);
+        return -1;
+    }else{
+        while(pos--)
+            get_byte(bc);
+        return 0;
+    }
+}
+
+static int decode_main_header(NUTContext *nut){
+    AVFormatContext *s= nut->avf;
+    ByteIOContext *bc = &s->pb;
+    uint64_t tmp, end;
+    unsigned int stream_count;
+    int i, j, tmp_stream, tmp_mul, tmp_pts, tmp_size, count, tmp_res;
+
+    end= get_packetheader(nut, bc, 1);
+    end += url_ftell(bc);
+
+    GET_V(tmp              , tmp >=2 && tmp <= 3)
+    GET_V(stream_count     , tmp > 0 && tmp <=MAX_STREAMS)
+
+    nut->max_distance = get_v(bc);
+    if(nut->max_distance > 65536){
+        av_log(s, AV_LOG_DEBUG, "max_distance %d\n", nut->max_distance);
+        nut->max_distance= 65536;
+    }
+
+    GET_V(nut->time_base_count, tmp>0 && tmp<INT_MAX / sizeof(AVRational))
+    nut->time_base= av_malloc(nut->time_base_count * sizeof(AVRational));
+
+    for(i=0; i<nut->time_base_count; i++){
+        GET_V(nut->time_base[i].num, tmp>0 && tmp<(1ULL<<31))
+        GET_V(nut->time_base[i].den, tmp>0 && tmp<(1ULL<<31))
+        if(ff_gcd(nut->time_base[i].num, nut->time_base[i].den) != 1){
+            av_log(s, AV_LOG_ERROR, "time base invalid\n");
+            return -1;
+        }
+    }
+    tmp_pts=0;
+    tmp_mul=1;
+    tmp_stream=0;
+    for(i=0; i<256;){
+        int tmp_flags = get_v(bc);
+        int tmp_fields= get_v(bc);
+        if(tmp_fields>0) tmp_pts   = 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 >= stream_count){
+            av_log(s, AV_LOG_ERROR, "illegal stream number\n");
+            return -1;
+        }
+
+        for(j=0; j<count; j++,i++){
+            if (i == 'N') {
+                nut->frame_code[i].flags= FLAG_INVALID;
+                j--;
+                continue;
+            }
+            nut->frame_code[i].flags           = tmp_flags ;
+            nut->frame_code[i].pts_delta       = tmp_pts   ;
+            nut->frame_code[i].stream_id       = 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   ;
+        }
+    }
+    assert(nut->frame_code['N'].flags == FLAG_INVALID);
+
+    if(skip_reserved(bc, end) || get_checksum(bc)){
+        av_log(s, AV_LOG_ERROR, "Main header checksum mismatch\n");
+        return -1;
+    }
+
+    nut->stream = av_mallocz(sizeof(StreamContext)*stream_count);
+    for(i=0; i<stream_count; i++){
+        av_new_stream(s, i);
+    }
+
+    return 0;
+}
+
+static int decode_stream_header(NUTContext *nut){
+    AVFormatContext *s= nut->avf;
+    ByteIOContext *bc = &s->pb;
+    StreamContext *stc;
+    int class, stream_id;
+    uint64_t tmp, end;
+    AVStream *st;
+
+    end= get_packetheader(nut, bc, 1);
+    end += url_ftell(bc);
+
+    GET_V(stream_id, tmp < s->nb_streams && !nut->stream[tmp].time_base.num);
+    stc= &nut->stream[stream_id];
+
+    st = s->streams[stream_id];
+    if (!st)
+        return AVERROR_NOMEM;
+
+    class = get_v(bc);
+    tmp = get_fourcc(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 1:
+            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;
+        case 2:
+//            st->codec->codec_type = CODEC_TYPE_TEXT;
+//            break;
+        case 3:
+            st->codec->codec_type = CODEC_TYPE_DATA;
+            break;
+        default:
+            av_log(s, AV_LOG_ERROR, "Unknown stream class (%d)\n", class);
+            return -1;
+    }
+    GET_V(stc->time_base_id    , tmp < nut->time_base_count);
+    GET_V(stc->msb_pts_shift   , tmp < 16);
+    stc->max_pts_distance= get_v(bc);
+    GET_V(stc->decode_delay    , tmp < 1000); //sanity limit, raise this if moors law is true
+    st->codec->has_b_frames= stc->decode_delay;
+    get_v(bc); //stream flags
+
+    GET_V(st->codec->extradata_size, tmp < (1<<30));
+    if(st->codec->extradata_size){
+        st->codec->extradata= av_mallocz(st->codec->extradata_size + FF_INPUT_BUFFER_PADDING_SIZE);
+        get_buffer(bc, st->codec->extradata, st->codec->extradata_size);
+    }
+
+    if (st->codec->codec_type == CODEC_TYPE_VIDEO){
+        GET_V(st->codec->width , tmp > 0)
+        GET_V(st->codec->height, tmp > 0)
+        st->codec->sample_aspect_ratio.num= get_v(bc);
+        st->codec->sample_aspect_ratio.den= get_v(bc);
+        if((!st->codec->sample_aspect_ratio.num) != (!st->codec->sample_aspect_ratio.den)){
+            av_log(s, AV_LOG_ERROR, "invalid aspect ratio\n");
+            return -1;
+        }
+        get_v(bc); /* csp type */
+    }else if (st->codec->codec_type == CODEC_TYPE_AUDIO){
+        GET_V(st->codec->sample_rate , tmp > 0)
+        tmp= get_v(bc); // samplerate_den
+        if(tmp > st->codec->sample_rate){
+            av_log(s, AV_LOG_ERROR, "bleh, libnut muxed this ;)\n");
+            st->codec->sample_rate= tmp;
+        }
+        GET_V(st->codec->channels, tmp > 0)
+    }
+    if(skip_reserved(bc, end) || get_checksum(bc)){
+        av_log(s, AV_LOG_ERROR, "Stream header %d checksum mismatch\n", stream_id);
+        return -1;
+    }
+    stc->time_base= nut->time_base[stc->time_base_id];
+    av_set_pts_info(s->streams[stream_id], 63, stc->time_base.num, stc->time_base.den);
+    return 0;
+}
+
+static int decode_info_header(NUTContext *nut){
+    AVFormatContext *s= nut->avf;
+    ByteIOContext *bc = &s->pb;
+    uint64_t tmp;
+    unsigned int stream_id_plus1, chapter_start, chapter_len, count;
+    int chapter_id, i;
+    int64_t value, end;
+    char name[256], str_value[1024], type_str[256], *type= type_str;
+
+    end= get_packetheader(nut, bc, 1);
+    end += url_ftell(bc);
+
+    GET_V(stream_id_plus1, tmp <= s->nb_streams)
+    chapter_id   = get_s(bc);
+    chapter_start= get_v(bc);
+    chapter_len  = get_v(bc);
+    count        = get_v(bc);
+    for(i=0; i<count; i++){
+        get_str(bc, name, sizeof(name));
+        value= get_s(bc);
+        if(value == -1){
+            type= "UTF-8";
+            get_str(bc, str_value, sizeof(str_value));
+        }else if(value == -2){
+            get_str(bc, type, sizeof(type));
+            get_str(bc, str_value, sizeof(str_value));
+        }else if(value == -3){
+            type= "s";
+            value= get_s(bc);
+        }else if(value == -4){
+            type= "t";
+            value= get_v(bc);
+        }else if(value < -4){
+            type= "r";
+            get_s(bc);
+        }else{
+            type= "v";
+        }
+
+        if(chapter_id==0 && !strcmp(type, "UTF-8")){
+            if     (!strcmp(name, "Author"))
+                pstrcpy(s->author   , sizeof(s->author)   , str_value);
+            else if(!strcmp(name, "Title"))
+                pstrcpy(s->title    , sizeof(s->title)    , str_value);
+            else if(!strcmp(name, "Copyright"))
+                pstrcpy(s->copyright, sizeof(s->copyright), str_value);
+            else if(!strcmp(name, "Description"))
+                pstrcpy(s->comment  , sizeof(s->comment)  , str_value);
+        }
+    }
+
+    if(skip_reserved(bc, end) || get_checksum(bc)){
+        av_log(s, AV_LOG_ERROR, "Info header checksum mismatch\n");
+        return -1;
+    }
+    return 0;
+}
+
+int sp_pos_cmp(syncpoint_t *a, syncpoint_t *b){
+    return (a->pos - b->pos>>32) - (b->pos - a->pos>>32);
+}
+
+int sp_pts_cmp(syncpoint_t *a, syncpoint_t *b){
+    return (a->ts - b->ts>>32) - (b->ts - a->ts>>32);
+}
+
+static void add_sp(NUTContext *nut, int64_t pos, int64_t back_ptr, int64_t ts){
+    syncpoint_t *sp2, *sp= av_mallocz(sizeof(syncpoint_t));
+
+    sp->pos= pos;
+    sp->back_ptr= back_ptr;
+    sp->ts= ts;
+    sp2= av_tree_insert(&nut->syncpoints, sp, sp_pos_cmp);
+    if(sp2 && sp2 != sp)
+        av_free(sp);
+}
+
+static int decode_syncpoint(NUTContext *nut, int64_t *ts, int64_t *back_ptr){
+    AVFormatContext *s= nut->avf;
+    ByteIOContext *bc = &s->pb;
+    int64_t end, tmp;
+    int i;
+    AVRational time_base;
+
+    nut->last_syncpoint_pos= url_ftell(bc)-8;
+
+    end= get_packetheader(nut, bc, 1);
+    end += url_ftell(bc);
+
+    tmp= get_v(bc);
+    *back_ptr= nut->last_syncpoint_pos - 16*get_v(bc);
+    if(*back_ptr < 0)
+        return -1;
+
+    time_base= nut->time_base[tmp % nut->time_base_count];
+    for(i=0; i<s->nb_streams; i++){
+        nut->stream[i].last_pts= av_rescale_rnd(
+            tmp / 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);
+        //last_key_frame ?
+    }
+    //FIXME put this in a reset func maybe
+
+    if(skip_reserved(bc, end) || get_checksum(bc)){
+        av_log(s, AV_LOG_ERROR, "sync point checksum mismatch\n");
+        return -1;
+    }
+
+    *ts= tmp / s->nb_streams * av_q2d(nut->time_base[tmp % s->nb_streams])*AV_TIME_BASE;
+    add_sp(nut, nut->last_syncpoint_pos, *back_ptr, *ts);
+
+    return 0;
+}
+
+static int find_and_decode_index(NUTContext *nut){
+    AVFormatContext *s= nut->avf;
+    ByteIOContext *bc = &s->pb;
+    uint64_t tmp, end;
+    int i, j, syncpoint_count;
+    int64_t filesize= url_fsize(bc);
+    int64_t *syncpoints;
+    int8_t *has_keyframe;
+
+    url_fseek(bc, filesize-12, SEEK_SET);
+    url_fseek(bc, filesize-get_be64(bc), SEEK_SET);
+    if(get_be64(bc) != INDEX_STARTCODE){
+        av_log(s, AV_LOG_ERROR, "no index at the end\n");
+        return -1;
+    }
+
+    end= get_packetheader(nut, bc, 1);
+    end += url_ftell(bc);
+
+    get_v(bc); //max_pts
+    GET_V(syncpoint_count, tmp < INT_MAX/8 && tmp > 0)
+    syncpoints= av_malloc(sizeof(int64_t)*syncpoint_count);
+    has_keyframe= av_malloc(sizeof(int8_t)*(syncpoint_count+1));
+    for(i=0; i<syncpoint_count; i++){
+        GET_V(syncpoints[i], tmp>0)
+        if(i)
+            syncpoints[i] += syncpoints[i-1];
+    }
+
+    for(i=0; i<s->nb_streams; i++){
+        int64_t last_pts= -1;
+        for(j=0; j<syncpoint_count;){
+            uint64_t x= get_v(bc);
+            int type= x&1;
+            int n= j;
+            x>>=1;
+            if(type){
+                int flag= x&1;
+                x>>=1;
+                if(n+x >= syncpoint_count + 1){
+                    av_log(s, AV_LOG_ERROR, "index overflow A\n");
+                    return -1;
+                }
+                while(x--)
+                    has_keyframe[n++]= flag;
+                has_keyframe[n++]= !flag;
+            }else{
+                while(x != 1){
+                    if(n>=syncpoint_count + 1){
+                        av_log(s, AV_LOG_ERROR, "index overflow B\n");
+                        return -1;
+                    }
+                    has_keyframe[n++]= x&1;
+                    x>>=1;
+                }
+            }
+            if(has_keyframe[0]){
+                av_log(s, AV_LOG_ERROR, "keyframe before first syncpoint in index\n");
+                return -1;
+            }
+            assert(n<=syncpoint_count+1);
+            for(; j<n; j++){
+                if(has_keyframe[j]){
+                    uint64_t B, A= get_v(bc);
+                    if(!A){
+                        A= get_v(bc);
+                        B= get_v(bc);
+                        //eor_pts[j][i] = last_pts + A + B
+                    }else
+                        B= 0;
+                    av_add_index_entry(
+                        s->streams[i],
+                        16*syncpoints[j-1],
+                        last_pts + A,
+                        0,
+                        0,
+                        AVINDEX_KEYFRAME);
+                    last_pts += A + B;
+                }
+            }
+        }
+    }
+
+    if(skip_reserved(bc, end) || get_checksum(bc)){
+        av_log(s, AV_LOG_ERROR, "Index checksum mismatch\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;
+
+    /* main header */
+    pos=0;
+    do{
+        pos= find_startcode(bc, MAIN_STARTCODE, pos)+1;
+        if (pos<0+1){
+            av_log(s, AV_LOG_ERROR, "no main startcode found\n");
+            return -1;
+        }
+    }while(decode_main_header(nut) < 0);
+
+    /* stream headers */
+    pos=0;
+    for(inited_stream_count=0; inited_stream_count < s->nb_streams;){
+        pos= find_startcode(bc, STREAM_STARTCODE, pos)+1;
+        if (pos<0+1){
+            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 == SYNCPOINT_STARTCODE){
+            nut->next_startcode= startcode;
+            break;
+        }else if(startcode != INFO_STARTCODE){
+            continue;
+        }
+
+        decode_info_header(nut);
+    }
+
+    s->data_offset= pos-8;
+
+    if(!url_is_streamed(bc)){
+        int64_t orig_pos= url_ftell(bc);
+        find_and_decode_index(nut);
+        url_fseek(bc, orig_pos, SEEK_SET);
+    }
+    assert(nut->next_startcode == SYNCPOINT_STARTCODE);
+
+    return 0;
+}
+
+static int decode_frame_header(NUTContext *nut, int64_t *pts, int *stream_id, int frame_code){
+    AVFormatContext *s= nut->avf;
+    ByteIOContext *bc = &s->pb;
+    StreamContext *stc;
+    int size, flags, size_mul, pts_delta, i, reserved_count;
+    uint64_t tmp;
+
+    if(url_ftell(bc) > nut->last_syncpoint_pos + nut->max_distance){
+        av_log(s, AV_LOG_ERROR, "last frame must have been damaged %Ld > %Ld + %d\n", url_ftell(bc), nut->last_syncpoint_pos, nut->max_distance);
+        return -1;
+    }
+
+    flags          = nut->frame_code[frame_code].flags;
+    size_mul       = nut->frame_code[frame_code].size_mul;
+    size           = nut->frame_code[frame_code].size_lsb;
+    *stream_id     = nut->frame_code[frame_code].stream_id;
+    pts_delta      = nut->frame_code[frame_code].pts_delta;
+    reserved_count = nut->frame_code[frame_code].reserved_count;
+
+    if(flags & FLAG_INVALID)
+        return -1;
+    if(flags & FLAG_CODED)
+        flags ^= get_v(bc);
+    if(flags & FLAG_STREAM_ID){
+        GET_V(*stream_id, tmp < s->nb_streams)
+    }
+    stc= &nut->stream[*stream_id];
+    if(flags&FLAG_CODED_PTS){
+        int coded_pts= get_v(bc);
+//FIXME check last_pts validity?
+        if(coded_pts < (1<<stc->msb_pts_shift)){
+            *pts=lsb2full(stc, coded_pts);
+        }else
+            *pts=coded_pts - (1<<stc->msb_pts_shift);
+    }else
+        *pts= stc->last_pts + pts_delta;
+    if(flags&FLAG_SIZE_MSB){
+        size += size_mul*get_v(bc);
+    }
+    if(flags&FLAG_RESERVED)
+        reserved_count= get_v(bc);
+    for(i=0; i<reserved_count; i++)
+        get_v(bc);
+    if(flags&FLAG_CHECKSUM){
+        get_be32(bc); //FIXME check this
+    }else if(size > 2*nut->max_distance || FFABS(stc->last_pts - *pts) > stc->max_pts_distance){
+        av_log(s, AV_LOG_ERROR, "frame size > 2max_distance and no checksum\n");
+        return -1;
+    }
+
+    stc->last_pts= *pts;
+    stc->last_flags= flags;
+
+    return size;
+}
+
+static int decode_frame(NUTContext *nut, AVPacket *pkt, int frame_code){
+    AVFormatContext *s= nut->avf;
+    ByteIOContext *bc = &s->pb;
+    int size, stream_id, discard;
+    int64_t pts, last_IP_pts;
+    StreamContext *stc;
+
+    size= decode_frame_header(nut, &pts, &stream_id, frame_code);
+    if(size < 0)
+        return -1;
+
+    stc= &nut->stream[stream_id];
+
+    if (stc->last_flags & FLAG_KEY)
+        stc->skip_until_key_frame=0;
+
+    discard= s->streams[ stream_id ]->discard;
+    last_IP_pts= s->streams[ stream_id ]->last_IP_pts;
+    if(  (discard >= AVDISCARD_NONKEY && !(stc->last_flags & FLAG_KEY))
+       ||(discard >= AVDISCARD_BIDIR && last_IP_pts != AV_NOPTS_VALUE && last_IP_pts > pts)
+       || discard >= AVDISCARD_ALL
+       || stc->skip_until_key_frame){
+        url_fskip(bc, size);
+        return 1;
+    }
+
+    av_get_packet(bc, pkt, size);
+    pkt->stream_index = stream_id;
+    if (stc->last_flags & FLAG_KEY)
+        pkt->flags |= PKT_FLAG_KEY;
+    pkt->pts = pts;
+
+    return 0;
+}
+
+static int nut_read_packet(AVFormatContext *s, AVPacket *pkt)
+{
+    NUTContext *nut = s->priv_data;
+    ByteIOContext *bc = &s->pb;
+    int i, frame_code=0, ret, skip;
+    int64_t ts, back_ptr;
+
+    for(;;){
+        int64_t pos= url_ftell(bc);
+        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:
+            skip= get_packetheader(nut, bc, 0);
+            url_fseek(bc, skip, SEEK_CUR);
+            break;
+        case INFO_STARTCODE:
+            if(decode_info_header(nut)<0)
+                goto resync;
+            break;
+        case SYNCPOINT_STARTCODE:
+            if(decode_syncpoint(nut, &ts, &back_ptr)<0)
+                goto resync;
+            frame_code = get_byte(bc);
+        case 0:
+            ret= decode_frame(nut, pkt, frame_code);
+            if(ret==0)
+                return 0;
+            else if(ret==1) //ok but discard packet
+                break;
+        default:
+resync:
+av_log(s, AV_LOG_DEBUG, "syncing from %"PRId64"\n", pos);
+            tmp= find_any_startcode(bc, nut->last_syncpoint_pos+1);
+            if(tmp==0)
+                return -1;
+av_log(s, AV_LOG_DEBUG, "sync\n");
+            nut->next_startcode= tmp;
+        }
+    }
+}
+
+static int64_t nut_read_timestamp(AVFormatContext *s, int stream_index, int64_t *pos_arg, int64_t pos_limit){
+    NUTContext *nut = s->priv_data;
+    ByteIOContext *bc = &s->pb;
+    int64_t pos, pts, back_ptr;
+av_log(s, AV_LOG_DEBUG, "read_timestamp(X,%d,%"PRId64",%"PRId64")\n", stream_index, *pos_arg, pos_limit);
+
+    pos= *pos_arg;
+resync:
+    do{
+        pos= find_startcode(bc, SYNCPOINT_STARTCODE, pos)+1;
+        if(pos < 1){
+            assert(nut->next_startcode == 0);
+            av_log(s, AV_LOG_ERROR, "read_timestamp failed\n");
+            return AV_NOPTS_VALUE;
+        }
+    }while(decode_syncpoint(nut, &pts, &back_ptr) < 0);
+    *pos_arg = pos-1;
+    assert(nut->last_syncpoint_pos == *pos_arg);
+
+    av_log(s, AV_LOG_DEBUG, "return %Ld %Ld\n", pts,back_ptr );
+    if     (stream_index == -1) return pts;
+    else if(stream_index == -2) return back_ptr;
+
+assert(0);
+}
+
+static int read_seek(AVFormatContext *s, int stream_index, int64_t pts, int flags){
+    NUTContext *nut = s->priv_data;
+    AVStream *st= s->streams[stream_index];
+    syncpoint_t dummy={.ts= pts*av_q2d(st->time_base)*AV_TIME_BASE};
+    syncpoint_t nopts_sp= {.ts= AV_NOPTS_VALUE, .back_ptr= AV_NOPTS_VALUE};
+    syncpoint_t *sp, *next_node[2]= {&nopts_sp, &nopts_sp};
+    int64_t pos, pos2, ts;
+    int i;
+
+    if(st->index_entries){
+        int index= av_index_search_timestamp(st, pts, flags);
+        if(index<0)
+            return -1;
+
+        pos2= st->index_entries[index].pos;
+        ts  = st->index_entries[index].timestamp;
+    }else{
+        av_tree_find(nut->syncpoints, &dummy, sp_pts_cmp, next_node);
+        av_log(s, AV_LOG_DEBUG, "%Ld-%Ld %Ld-%Ld\n", next_node[0]->pos, next_node[1]->pos,
+                                                    next_node[0]->ts , next_node[1]->ts);
+        pos= av_gen_search(s, -1, dummy.ts, next_node[0]->pos, next_node[1]->pos, next_node[1]->pos,
+                                            next_node[0]->ts , next_node[1]->ts, AVSEEK_FLAG_BACKWARD, &ts, nut_read_timestamp);
+
+        if(!(flags & AVSEEK_FLAG_BACKWARD)){
+            dummy.pos= pos+16;
+            next_node[1]= &nopts_sp;
+            av_tree_find(nut->syncpoints, &dummy, sp_pos_cmp, next_node);
+            pos2= av_gen_search(s, -2, dummy.pos, next_node[0]->pos     , next_node[1]->pos, next_node[1]->pos,
+                                                next_node[0]->back_ptr, next_node[1]->back_ptr, flags, &ts, nut_read_timestamp);
+            if(pos2>=0)
+                pos= pos2;
+            //FIXME dir but i think it doesnt matter
+        }
+        dummy.pos= pos;
+        sp= av_tree_find(nut->syncpoints, &dummy, sp_pos_cmp, NULL);
+
+        assert(sp);
+        pos2= sp->back_ptr  - 15;
+    }
+    av_log(NULL, AV_LOG_DEBUG, "SEEKTO: %"PRId64"\n", pos2);
+    pos= find_startcode(&s->pb, SYNCPOINT_STARTCODE, pos2);
+    url_fseek(&s->pb, pos, SEEK_SET);
+    av_log(NULL, AV_LOG_DEBUG, "SP: %"PRId64"\n", pos);
+    if(pos2 > pos || pos2 + 15 < pos){
+        av_log(NULL, AV_LOG_ERROR, "no syncpoint at backptr pos\n");
+    }
+    for(i=0; i<s->nb_streams; i++)
+        nut->stream[i].skip_until_key_frame=1;
+
+    return 0;
+}
+
+static int nut_read_close(AVFormatContext *s)
+{
+    NUTContext *nut = s->priv_data;
+
+    av_freep(&nut->time_base);
+    av_freep(&nut->stream);
+
+    return 0;
+}
+
+#ifdef CONFIG_NUT_DEMUXER
+AVInputFormat nut_demuxer = {
+    "nut",
+    "nut format",
+    sizeof(NUTContext),
+    nut_probe,
+    nut_read_header,
+    nut_read_packet,
+    nut_read_close,
+    read_seek,
+    .extensions = "nut",
+};
+#endif