libavformat/nutenc.c
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00001 /*
00002  * nut muxer
00003  * Copyright (c) 2004-2007 Michael Niedermayer
00004  *
00005  * This file is part of FFmpeg.
00006  *
00007  * FFmpeg is free software; you can redistribute it and/or
00008  * modify it under the terms of the GNU Lesser General Public
00009  * License as published by the Free Software Foundation; either
00010  * version 2.1 of the License, or (at your option) any later version.
00011  *
00012  * FFmpeg is distributed in the hope that it will be useful,
00013  * but WITHOUT ANY WARRANTY; without even the implied warranty of
00014  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
00015  * Lesser General Public License for more details.
00016  *
00017  * You should have received a copy of the GNU Lesser General Public
00018  * License along with FFmpeg; if not, write to the Free Software
00019  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
00020  */
00021 
00022 #include "libavutil/intreadwrite.h"
00023 #include "libavutil/mathematics.h"
00024 #include "libavutil/tree.h"
00025 #include "libavutil/dict.h"
00026 #include "libavcodec/mpegaudiodata.h"
00027 #include "nut.h"
00028 #include "internal.h"
00029 #include "avio_internal.h"
00030 
00031 static int find_expected_header(AVCodecContext *c, int size, int key_frame, uint8_t out[64]){
00032     int sample_rate= c->sample_rate;
00033 
00034     if(size>4096)
00035         return 0;
00036 
00037     AV_WB24(out, 1);
00038 
00039     if(c->codec_id == CODEC_ID_MPEG4){
00040         if(key_frame){
00041             return 3;
00042         }else{
00043             out[3]= 0xB6;
00044             return 4;
00045         }
00046     }else if(c->codec_id == CODEC_ID_MPEG1VIDEO || c->codec_id == CODEC_ID_MPEG2VIDEO){
00047         return 3;
00048     }else if(c->codec_id == CODEC_ID_H264){
00049         return 3;
00050     }else if(c->codec_id == CODEC_ID_MP3 || c->codec_id == CODEC_ID_MP2){
00051         int lsf, mpeg25, sample_rate_index, bitrate_index, frame_size;
00052         int layer= c->codec_id == CODEC_ID_MP3 ? 3 : 2;
00053         unsigned int header= 0xFFF00000;
00054 
00055         lsf     = sample_rate < (24000+32000)/2;
00056         mpeg25  = sample_rate < (12000+16000)/2;
00057         sample_rate <<= lsf + mpeg25;
00058         if     (sample_rate < (32000 + 44100)/2) sample_rate_index=2;
00059         else if(sample_rate < (44100 + 48000)/2) sample_rate_index=0;
00060         else                                     sample_rate_index=1;
00061 
00062         sample_rate= avpriv_mpa_freq_tab[sample_rate_index] >> (lsf + mpeg25);
00063 
00064         for(bitrate_index=2; bitrate_index<30; bitrate_index++){
00065             frame_size = avpriv_mpa_bitrate_tab[lsf][layer-1][bitrate_index>>1];
00066             frame_size = (frame_size * 144000) / (sample_rate << lsf) + (bitrate_index&1);
00067 
00068             if(frame_size == size)
00069                 break;
00070         }
00071 
00072         header |= (!lsf)<<19;
00073         header |= (4-layer)<<17;
00074         header |= 1<<16; //no crc
00075         AV_WB32(out, header);
00076         if(size <= 0)
00077             return 2; //we guess there is no crc, if there is one the user clearly does not care about overhead
00078         if(bitrate_index == 30)
00079             return -1; //something is wrong ...
00080 
00081         header |= (bitrate_index>>1)<<12;
00082         header |= sample_rate_index<<10;
00083         header |= (bitrate_index&1)<<9;
00084 
00085         return 2; //FIXME actually put the needed ones in build_elision_headers()
00086         return 3; //we guess that the private bit is not set
00087 //FIXME the above assumptions should be checked, if these turn out false too often something should be done
00088     }
00089     return 0;
00090 }
00091 
00092 static int find_header_idx(AVFormatContext *s, AVCodecContext *c, int size, int frame_type){
00093     NUTContext *nut = s->priv_data;
00094     uint8_t out[64];
00095     int i;
00096     int len= find_expected_header(c, size, frame_type, out);
00097 
00098 //av_log(NULL, AV_LOG_ERROR, "expected_h len=%d size=%d codec_id=%d\n", len, size, c->codec_id);
00099 
00100     for(i=1; i<nut->header_count; i++){
00101         if(   len == nut->header_len[i]
00102            && !memcmp(out, nut->header[i], len)){
00103 //    av_log(NULL, AV_LOG_ERROR, "found %d\n", i);
00104             return i;
00105         }
00106     }
00107 //    av_log(NULL, AV_LOG_ERROR, "nothing found\n");
00108     return 0;
00109 }
00110 
00111 static void build_elision_headers(AVFormatContext *s){
00112     NUTContext *nut = s->priv_data;
00113     int i;
00114     //FIXME this is lame
00115     //FIXME write a 2pass mode to find the maximal headers
00116     static const uint8_t headers[][5]={
00117         {3, 0x00, 0x00, 0x01},
00118         {4, 0x00, 0x00, 0x01, 0xB6},
00119         {2, 0xFF, 0xFA}, //mp3+crc
00120         {2, 0xFF, 0xFB}, //mp3
00121         {2, 0xFF, 0xFC}, //mp2+crc
00122         {2, 0xFF, 0xFD}, //mp2
00123     };
00124 
00125     nut->header_count= 7;
00126     for(i=1; i<nut->header_count; i++){
00127         nut->header_len[i]=  headers[i-1][0];
00128         nut->header    [i]= &headers[i-1][1];
00129     }
00130 }
00131 
00132 static void build_frame_code(AVFormatContext *s){
00133     NUTContext *nut = s->priv_data;
00134     int key_frame, index, pred, stream_id;
00135     int start=1;
00136     int end= 254;
00137     int keyframe_0_esc= s->nb_streams > 2;
00138     int pred_table[10];
00139     FrameCode *ft;
00140 
00141     ft= &nut->frame_code[start];
00142     ft->flags= FLAG_CODED;
00143     ft->size_mul=1;
00144     ft->pts_delta=1;
00145     start++;
00146 
00147     if(keyframe_0_esc){
00148         /* keyframe = 0 escape */
00149         FrameCode *ft= &nut->frame_code[start];
00150         ft->flags= FLAG_STREAM_ID | FLAG_SIZE_MSB | FLAG_CODED_PTS;
00151         ft->size_mul=1;
00152         start++;
00153     }
00154 
00155     for(stream_id= 0; stream_id<s->nb_streams; stream_id++){
00156         int start2= start + (end-start)*stream_id / s->nb_streams;
00157         int end2  = start + (end-start)*(stream_id+1) / s->nb_streams;
00158         AVCodecContext *codec = s->streams[stream_id]->codec;
00159         int is_audio= codec->codec_type == AVMEDIA_TYPE_AUDIO;
00160         int intra_only= /*codec->intra_only || */is_audio;
00161         int pred_count;
00162 
00163         for(key_frame=0; key_frame<2; key_frame++){
00164             if(intra_only && keyframe_0_esc && key_frame==0)
00165                 continue;
00166 
00167             {
00168                 FrameCode *ft= &nut->frame_code[start2];
00169                 ft->flags= FLAG_KEY*key_frame;
00170                 ft->flags|= FLAG_SIZE_MSB | FLAG_CODED_PTS;
00171                 ft->stream_id= stream_id;
00172                 ft->size_mul=1;
00173                 if(is_audio)
00174                     ft->header_idx= find_header_idx(s, codec, -1, key_frame);
00175                 start2++;
00176             }
00177         }
00178 
00179         key_frame= intra_only;
00180 #if 1
00181         if(is_audio){
00182             int frame_bytes= codec->frame_size*(int64_t)codec->bit_rate / (8*codec->sample_rate);
00183             int pts;
00184             for(pts=0; pts<2; pts++){
00185                 for(pred=0; pred<2; pred++){
00186                     FrameCode *ft= &nut->frame_code[start2];
00187                     ft->flags= FLAG_KEY*key_frame;
00188                     ft->stream_id= stream_id;
00189                     ft->size_mul=frame_bytes + 2;
00190                     ft->size_lsb=frame_bytes + pred;
00191                     ft->pts_delta=pts;
00192                     ft->header_idx= find_header_idx(s, codec, frame_bytes + pred, key_frame);
00193                     start2++;
00194                 }
00195             }
00196         }else{
00197             FrameCode *ft= &nut->frame_code[start2];
00198             ft->flags= FLAG_KEY | FLAG_SIZE_MSB;
00199             ft->stream_id= stream_id;
00200             ft->size_mul=1;
00201             ft->pts_delta=1;
00202             start2++;
00203         }
00204 #endif
00205 
00206         if(codec->has_b_frames){
00207             pred_count=5;
00208             pred_table[0]=-2;
00209             pred_table[1]=-1;
00210             pred_table[2]=1;
00211             pred_table[3]=3;
00212             pred_table[4]=4;
00213         }else if(codec->codec_id == CODEC_ID_VORBIS){
00214             pred_count=3;
00215             pred_table[0]=2;
00216             pred_table[1]=9;
00217             pred_table[2]=16;
00218         }else{
00219             pred_count=1;
00220             pred_table[0]=1;
00221         }
00222 
00223         for(pred=0; pred<pred_count; pred++){
00224             int start3= start2 + (end2-start2)*pred / pred_count;
00225             int end3  = start2 + (end2-start2)*(pred+1) / pred_count;
00226 
00227             for(index=start3; index<end3; index++){
00228                 FrameCode *ft= &nut->frame_code[index];
00229                 ft->flags= FLAG_KEY*key_frame;
00230                 ft->flags|= FLAG_SIZE_MSB;
00231                 ft->stream_id= stream_id;
00232 //FIXME use single byte size and pred from last
00233                 ft->size_mul= end3-start3;
00234                 ft->size_lsb= index - start3;
00235                 ft->pts_delta= pred_table[pred];
00236                 if(is_audio)
00237                     ft->header_idx= find_header_idx(s, codec, -1, key_frame);
00238             }
00239         }
00240     }
00241     memmove(&nut->frame_code['N'+1], &nut->frame_code['N'], sizeof(FrameCode)*(255-'N'));
00242     nut->frame_code[  0].flags=
00243     nut->frame_code[255].flags=
00244     nut->frame_code['N'].flags= FLAG_INVALID;
00245 }
00246 
00247 static void put_tt(NUTContext *nut, AVRational *time_base, AVIOContext *bc, uint64_t val){
00248     val *= nut->time_base_count;
00249     val += time_base - nut->time_base;
00250     ff_put_v(bc, val);
00251 }
00252 
00256 static void put_str(AVIOContext *bc, const char *string){
00257     int len= strlen(string);
00258 
00259     ff_put_v(bc, len);
00260     avio_write(bc, string, len);
00261 }
00262 
00263 static void put_s(AVIOContext *bc, int64_t val){
00264     ff_put_v(bc, 2*FFABS(val) - (val>0));
00265 }
00266 
00267 #ifdef TRACE
00268 static inline void ff_put_v_trace(AVIOContext *bc, uint64_t v, char *file, char *func, int line){
00269     av_log(NULL, AV_LOG_DEBUG, "ff_put_v %5"PRId64" / %"PRIX64" in %s %s:%d\n", v, v, file, func, line);
00270 
00271     ff_put_v(bc, v);
00272 }
00273 
00274 static inline void put_s_trace(AVIOContext *bc, int64_t v, char *file, char *func, int line){
00275     av_log(NULL, AV_LOG_DEBUG, "put_s %5"PRId64" / %"PRIX64" in %s %s:%d\n", v, v, file, func, line);
00276 
00277     put_s(bc, v);
00278 }
00279 #define ff_put_v(bc, v)  ff_put_v_trace(bc, v, __FILE__, __PRETTY_FUNCTION__, __LINE__)
00280 #define put_s(bc, v)  put_s_trace(bc, v, __FILE__, __PRETTY_FUNCTION__, __LINE__)
00281 #endif
00282 
00283 //FIXME remove calculate_checksum
00284 static void put_packet(NUTContext *nut, AVIOContext *bc, AVIOContext *dyn_bc, int calculate_checksum, uint64_t startcode){
00285     uint8_t *dyn_buf=NULL;
00286     int dyn_size= avio_close_dyn_buf(dyn_bc, &dyn_buf);
00287     int forw_ptr= dyn_size + 4*calculate_checksum;
00288 
00289     if(forw_ptr > 4096)
00290         ffio_init_checksum(bc, ff_crc04C11DB7_update, 0);
00291     avio_wb64(bc, startcode);
00292     ff_put_v(bc, forw_ptr);
00293     if(forw_ptr > 4096)
00294         avio_wl32(bc, ffio_get_checksum(bc));
00295 
00296     if(calculate_checksum)
00297         ffio_init_checksum(bc, ff_crc04C11DB7_update, 0);
00298     avio_write(bc, dyn_buf, dyn_size);
00299     if(calculate_checksum)
00300         avio_wl32(bc, ffio_get_checksum(bc));
00301 
00302     av_free(dyn_buf);
00303 }
00304 
00305 static void write_mainheader(NUTContext *nut, AVIOContext *bc){
00306     int i, j, tmp_pts, tmp_flags, tmp_stream, tmp_mul, tmp_size, tmp_fields, tmp_head_idx;
00307     int64_t tmp_match;
00308 
00309     ff_put_v(bc, 3); /* version */
00310     ff_put_v(bc, nut->avf->nb_streams);
00311     ff_put_v(bc, nut->max_distance);
00312     ff_put_v(bc, nut->time_base_count);
00313 
00314     for(i=0; i<nut->time_base_count; i++){
00315         ff_put_v(bc, nut->time_base[i].num);
00316         ff_put_v(bc, nut->time_base[i].den);
00317     }
00318 
00319     tmp_pts=0;
00320     tmp_mul=1;
00321     tmp_stream=0;
00322     tmp_match= 1-(1LL<<62);
00323     tmp_head_idx= 0;
00324     for(i=0; i<256;){
00325         tmp_fields=0;
00326         tmp_size=0;
00327 //        tmp_res=0;
00328         if(tmp_pts    != nut->frame_code[i].pts_delta) tmp_fields=1;
00329         if(tmp_mul    != nut->frame_code[i].size_mul ) tmp_fields=2;
00330         if(tmp_stream != nut->frame_code[i].stream_id) tmp_fields=3;
00331         if(tmp_size   != nut->frame_code[i].size_lsb ) tmp_fields=4;
00332 //        if(tmp_res    != nut->frame_code[i].res            ) tmp_fields=5;
00333         if(tmp_head_idx!=nut->frame_code[i].header_idx)tmp_fields=8;
00334 
00335         tmp_pts   = nut->frame_code[i].pts_delta;
00336         tmp_flags = nut->frame_code[i].flags;
00337         tmp_stream= nut->frame_code[i].stream_id;
00338         tmp_mul   = nut->frame_code[i].size_mul;
00339         tmp_size  = nut->frame_code[i].size_lsb;
00340 //        tmp_res   = nut->frame_code[i].res;
00341         tmp_head_idx= nut->frame_code[i].header_idx;
00342 
00343         for(j=0; i<256; j++,i++){
00344             if(i == 'N'){
00345                 j--;
00346                 continue;
00347             }
00348             if(nut->frame_code[i].pts_delta != tmp_pts   ) break;
00349             if(nut->frame_code[i].flags     != tmp_flags ) break;
00350             if(nut->frame_code[i].stream_id != tmp_stream) break;
00351             if(nut->frame_code[i].size_mul  != tmp_mul   ) break;
00352             if(nut->frame_code[i].size_lsb  != tmp_size+j) break;
00353 //            if(nut->frame_code[i].res       != tmp_res   ) break;
00354             if(nut->frame_code[i].header_idx!= tmp_head_idx) break;
00355         }
00356         if(j != tmp_mul - tmp_size) tmp_fields=6;
00357 
00358         ff_put_v(bc, tmp_flags);
00359         ff_put_v(bc, tmp_fields);
00360         if(tmp_fields>0) put_s(bc, tmp_pts);
00361         if(tmp_fields>1) ff_put_v(bc, tmp_mul);
00362         if(tmp_fields>2) ff_put_v(bc, tmp_stream);
00363         if(tmp_fields>3) ff_put_v(bc, tmp_size);
00364         if(tmp_fields>4) ff_put_v(bc, 0 /*tmp_res*/);
00365         if(tmp_fields>5) ff_put_v(bc, j);
00366         if(tmp_fields>6) ff_put_v(bc, tmp_match);
00367         if(tmp_fields>7) ff_put_v(bc, tmp_head_idx);
00368     }
00369     ff_put_v(bc, nut->header_count-1);
00370     for(i=1; i<nut->header_count; i++){
00371         ff_put_v(bc, nut->header_len[i]);
00372         avio_write(bc, nut->header[i], nut->header_len[i]);
00373     }
00374 }
00375 
00376 static int write_streamheader(AVFormatContext *avctx, AVIOContext *bc, AVStream *st, int i){
00377     NUTContext *nut = avctx->priv_data;
00378     AVCodecContext *codec = st->codec;
00379     ff_put_v(bc, i);
00380     switch(codec->codec_type){
00381     case AVMEDIA_TYPE_VIDEO: ff_put_v(bc, 0); break;
00382     case AVMEDIA_TYPE_AUDIO: ff_put_v(bc, 1); break;
00383     case AVMEDIA_TYPE_SUBTITLE: ff_put_v(bc, 2); break;
00384     default              : ff_put_v(bc, 3); break;
00385     }
00386     ff_put_v(bc, 4);
00387     if (codec->codec_tag){
00388         avio_wl32(bc, codec->codec_tag);
00389     } else {
00390         av_log(avctx, AV_LOG_ERROR, "No codec tag defined for stream %d\n", i);
00391         return AVERROR(EINVAL);
00392     }
00393 
00394     ff_put_v(bc, nut->stream[i].time_base - nut->time_base);
00395     ff_put_v(bc, nut->stream[i].msb_pts_shift);
00396     ff_put_v(bc, nut->stream[i].max_pts_distance);
00397     ff_put_v(bc, codec->has_b_frames);
00398     avio_w8(bc, 0); /* flags: 0x1 - fixed_fps, 0x2 - index_present */
00399 
00400     ff_put_v(bc, codec->extradata_size);
00401     avio_write(bc, codec->extradata, codec->extradata_size);
00402 
00403     switch(codec->codec_type){
00404     case AVMEDIA_TYPE_AUDIO:
00405         ff_put_v(bc, codec->sample_rate);
00406         ff_put_v(bc, 1);
00407         ff_put_v(bc, codec->channels);
00408         break;
00409     case AVMEDIA_TYPE_VIDEO:
00410         ff_put_v(bc, codec->width);
00411         ff_put_v(bc, codec->height);
00412 
00413         if(st->sample_aspect_ratio.num<=0 || st->sample_aspect_ratio.den<=0){
00414             ff_put_v(bc, 0);
00415             ff_put_v(bc, 0);
00416         }else{
00417             ff_put_v(bc, st->sample_aspect_ratio.num);
00418             ff_put_v(bc, st->sample_aspect_ratio.den);
00419         }
00420         ff_put_v(bc, 0); /* csp type -- unknown */
00421         break;
00422     default:
00423         break;
00424     }
00425     return 0;
00426 }
00427 
00428 static int add_info(AVIOContext *bc, const char *type, const char *value){
00429     put_str(bc, type);
00430     put_s(bc, -1);
00431     put_str(bc, value);
00432     return 1;
00433 }
00434 
00435 static int write_globalinfo(NUTContext *nut, AVIOContext *bc){
00436     AVFormatContext *s= nut->avf;
00437     AVDictionaryEntry *t = NULL;
00438     AVIOContext *dyn_bc;
00439     uint8_t *dyn_buf=NULL;
00440     int count=0, dyn_size;
00441     int ret = avio_open_dyn_buf(&dyn_bc);
00442     if(ret < 0)
00443         return ret;
00444 
00445     while ((t = av_dict_get(s->metadata, "", t, AV_DICT_IGNORE_SUFFIX)))
00446         count += add_info(dyn_bc, t->key, t->value);
00447 
00448     ff_put_v(bc, 0); //stream_if_plus1
00449     ff_put_v(bc, 0); //chapter_id
00450     ff_put_v(bc, 0); //timestamp_start
00451     ff_put_v(bc, 0); //length
00452 
00453     ff_put_v(bc, count);
00454 
00455     dyn_size= avio_close_dyn_buf(dyn_bc, &dyn_buf);
00456     avio_write(bc, dyn_buf, dyn_size);
00457     av_free(dyn_buf);
00458     return 0;
00459 }
00460 
00461 static int write_streaminfo(NUTContext *nut, AVIOContext *bc, int stream_id){
00462     AVFormatContext *s= nut->avf;
00463     AVStream* st = s->streams[stream_id];
00464     AVIOContext *dyn_bc;
00465     uint8_t *dyn_buf=NULL;
00466     int count=0, dyn_size, i;
00467     int ret = avio_open_dyn_buf(&dyn_bc);
00468     if(ret < 0)
00469         return ret;
00470 
00471     for (i=0; ff_nut_dispositions[i].flag; ++i) {
00472         if (st->disposition & ff_nut_dispositions[i].flag)
00473             count += add_info(dyn_bc, "Disposition", ff_nut_dispositions[i].str);
00474     }
00475     dyn_size = avio_close_dyn_buf(dyn_bc, &dyn_buf);
00476 
00477     if (count) {
00478         ff_put_v(bc, stream_id + 1); //stream_id_plus1
00479         ff_put_v(bc, 0); //chapter_id
00480         ff_put_v(bc, 0); //timestamp_start
00481         ff_put_v(bc, 0); //length
00482 
00483         ff_put_v(bc, count);
00484 
00485         avio_write(bc, dyn_buf, dyn_size);
00486     }
00487 
00488     av_free(dyn_buf);
00489     return count;
00490 }
00491 
00492 static int write_chapter(NUTContext *nut, AVIOContext *bc, int id)
00493 {
00494     AVIOContext *dyn_bc;
00495     uint8_t *dyn_buf = NULL;
00496     AVDictionaryEntry *t = NULL;
00497     AVChapter *ch    = nut->avf->chapters[id];
00498     int ret, dyn_size, count = 0;
00499 
00500     ret = avio_open_dyn_buf(&dyn_bc);
00501     if (ret < 0)
00502         return ret;
00503 
00504     ff_put_v(bc, 0);                                        // stream_id_plus1
00505     put_s(bc, id + 1);                                      // chapter_id
00506     put_tt(nut, nut->chapter[id].time_base, bc, ch->start); // chapter_start
00507     ff_put_v(bc, ch->end - ch->start);                      // chapter_len
00508 
00509     while ((t = av_dict_get(ch->metadata, "", t, AV_DICT_IGNORE_SUFFIX)))
00510         count += add_info(dyn_bc, t->key, t->value);
00511 
00512     ff_put_v(bc, count);
00513 
00514     dyn_size = avio_close_dyn_buf(dyn_bc, &dyn_buf);
00515     avio_write(bc, dyn_buf, dyn_size);
00516     av_freep(&dyn_buf);
00517     return 0;
00518 }
00519 
00520 static int write_headers(AVFormatContext *avctx, AVIOContext *bc){
00521     NUTContext *nut = avctx->priv_data;
00522     AVIOContext *dyn_bc;
00523     int i, ret;
00524 
00525     ff_metadata_conv_ctx(avctx, ff_nut_metadata_conv, NULL);
00526 
00527     ret = avio_open_dyn_buf(&dyn_bc);
00528     if(ret < 0)
00529         return ret;
00530     write_mainheader(nut, dyn_bc);
00531     put_packet(nut, bc, dyn_bc, 1, MAIN_STARTCODE);
00532 
00533     for (i=0; i < nut->avf->nb_streams; i++){
00534         ret = avio_open_dyn_buf(&dyn_bc);
00535         if(ret < 0)
00536             return ret;
00537         if ((ret = write_streamheader(avctx, dyn_bc, nut->avf->streams[i], i)) < 0)
00538             return ret;
00539         put_packet(nut, bc, dyn_bc, 1, STREAM_STARTCODE);
00540     }
00541 
00542     ret = avio_open_dyn_buf(&dyn_bc);
00543     if(ret < 0)
00544         return ret;
00545     write_globalinfo(nut, dyn_bc);
00546     put_packet(nut, bc, dyn_bc, 1, INFO_STARTCODE);
00547 
00548     for (i = 0; i < nut->avf->nb_streams; i++) {
00549         ret = avio_open_dyn_buf(&dyn_bc);
00550         if(ret < 0)
00551             return ret;
00552         ret = write_streaminfo(nut, dyn_bc, i);
00553         if (ret < 0)
00554             return ret;
00555         if (ret > 0)
00556             put_packet(nut, bc, dyn_bc, 1, INFO_STARTCODE);
00557         else {
00558             uint8_t* buf;
00559             avio_close_dyn_buf(dyn_bc, &buf);
00560             av_free(buf);
00561         }
00562     }
00563 
00564     for (i = 0; i < nut->avf->nb_chapters; i++) {
00565         ret = avio_open_dyn_buf(&dyn_bc);
00566         if (ret < 0)
00567             return ret;
00568         ret = write_chapter(nut, dyn_bc, i);
00569         if (ret < 0) {
00570             uint8_t *buf;
00571             avio_close_dyn_buf(dyn_bc, &buf);
00572             av_freep(&buf);
00573             return ret;
00574         }
00575         put_packet(nut, bc, dyn_bc, 1, INFO_STARTCODE);
00576     }
00577 
00578     nut->last_syncpoint_pos= INT_MIN;
00579     nut->header_count++;
00580     return 0;
00581 }
00582 
00583 static int nut_write_header(AVFormatContext *s){
00584     NUTContext *nut = s->priv_data;
00585     AVIOContext *bc = s->pb;
00586     int i, j, ret;
00587 
00588     nut->avf= s;
00589 
00590     nut->stream   = av_mallocz(sizeof(StreamContext)*s->nb_streams);
00591     nut->chapter  = av_mallocz(sizeof(ChapterContext)*s->nb_chapters);
00592     nut->time_base= av_mallocz(sizeof(AVRational   )*(s->nb_streams +
00593                                                       s->nb_chapters));
00594     if (!nut->stream || !nut->chapter || !nut->time_base) {
00595         av_freep(&nut->stream);
00596         av_freep(&nut->chapter);
00597         av_freep(&nut->time_base);
00598         return AVERROR(ENOMEM);
00599     }
00600 
00601     for(i=0; i<s->nb_streams; i++){
00602         AVStream *st= s->streams[i];
00603         int ssize;
00604         AVRational time_base;
00605         ff_parse_specific_params(st->codec, &time_base.den, &ssize, &time_base.num);
00606 
00607         avpriv_set_pts_info(st, 64, time_base.num, time_base.den);
00608 
00609         for(j=0; j<nut->time_base_count; j++){
00610             if(!memcmp(&time_base, &nut->time_base[j], sizeof(AVRational))){
00611                 break;
00612             }
00613         }
00614         nut->time_base[j]= time_base;
00615         nut->stream[i].time_base= &nut->time_base[j];
00616         if(j==nut->time_base_count)
00617             nut->time_base_count++;
00618 
00619         if(INT64_C(1000) * time_base.num >= time_base.den)
00620             nut->stream[i].msb_pts_shift = 7;
00621         else
00622             nut->stream[i].msb_pts_shift = 14;
00623         nut->stream[i].max_pts_distance= FFMAX(time_base.den, time_base.num) / time_base.num;
00624     }
00625 
00626     for (i = 0; i < s->nb_chapters; i++) {
00627         AVChapter *ch = s->chapters[i];
00628 
00629         for (j = 0; j < nut->time_base_count; j++) {
00630             if (!memcmp(&ch->time_base, &nut->time_base[j], sizeof(AVRational)))
00631                 break;
00632         }
00633 
00634         nut->time_base[j] = ch->time_base;
00635         nut->chapter[i].time_base = &nut->time_base[j];
00636         if(j == nut->time_base_count)
00637             nut->time_base_count++;
00638     }
00639 
00640     nut->max_distance = MAX_DISTANCE;
00641     build_elision_headers(s);
00642     build_frame_code(s);
00643     assert(nut->frame_code['N'].flags == FLAG_INVALID);
00644 
00645     avio_write(bc, ID_STRING, strlen(ID_STRING));
00646     avio_w8(bc, 0);
00647 
00648     if ((ret = write_headers(s, bc)) < 0)
00649         return ret;
00650 
00651     avio_flush(bc);
00652 
00653     //FIXME index
00654 
00655     return 0;
00656 }
00657 
00658 static int get_needed_flags(NUTContext *nut, StreamContext *nus, FrameCode *fc, AVPacket *pkt){
00659     int flags= 0;
00660 
00661     if(pkt->flags & AV_PKT_FLAG_KEY             ) flags |= FLAG_KEY;
00662     if(pkt->stream_index != fc->stream_id       ) flags |= FLAG_STREAM_ID;
00663     if(pkt->size / fc->size_mul                 ) flags |= FLAG_SIZE_MSB;
00664     if(pkt->pts - nus->last_pts != fc->pts_delta) flags |= FLAG_CODED_PTS;
00665     if(pkt->size > 2*nut->max_distance          ) flags |= FLAG_CHECKSUM;
00666     if(FFABS(pkt->pts - nus->last_pts)
00667                          > nus->max_pts_distance) flags |= FLAG_CHECKSUM;
00668     if(   pkt->size < nut->header_len[fc->header_idx]
00669        || (pkt->size > 4096 && fc->header_idx)
00670        || memcmp(pkt->data, nut->header[fc->header_idx], nut->header_len[fc->header_idx]))
00671                                                   flags |= FLAG_HEADER_IDX;
00672 
00673     return flags | (fc->flags & FLAG_CODED);
00674 }
00675 
00676 static int find_best_header_idx(NUTContext *nut, AVPacket *pkt){
00677     int i;
00678     int best_i  = 0;
00679     int best_len= 0;
00680 
00681     if(pkt->size > 4096)
00682         return 0;
00683 
00684     for(i=1; i<nut->header_count; i++){
00685         if(   pkt->size >= nut->header_len[i]
00686            &&  nut->header_len[i] > best_len
00687            && !memcmp(pkt->data, nut->header[i], nut->header_len[i])){
00688             best_i= i;
00689             best_len= nut->header_len[i];
00690         }
00691     }
00692     return best_i;
00693 }
00694 
00695 static int nut_write_packet(AVFormatContext *s, AVPacket *pkt){
00696     NUTContext *nut = s->priv_data;
00697     StreamContext *nus= &nut->stream[pkt->stream_index];
00698     AVIOContext *bc = s->pb, *dyn_bc;
00699     FrameCode *fc;
00700     int64_t coded_pts;
00701     int best_length, frame_code, flags, needed_flags, i, header_idx, best_header_idx;
00702     int key_frame = !!(pkt->flags & AV_PKT_FLAG_KEY);
00703     int store_sp=0;
00704     int ret;
00705 
00706     if(pkt->pts < 0)
00707         return -1;
00708 
00709     if(1LL<<(20+3*nut->header_count) <= avio_tell(bc))
00710         write_headers(s, bc);
00711 
00712     if(key_frame && !(nus->last_flags & FLAG_KEY))
00713         store_sp= 1;
00714 
00715     if(pkt->size + 30/*FIXME check*/ + avio_tell(bc) >= nut->last_syncpoint_pos + nut->max_distance)
00716         store_sp= 1;
00717 
00718 //FIXME: Ensure store_sp is 1 in the first place.
00719 
00720     if(store_sp){
00721         Syncpoint *sp, dummy= {.pos= INT64_MAX};
00722 
00723         ff_nut_reset_ts(nut, *nus->time_base, pkt->dts);
00724         for(i=0; i<s->nb_streams; i++){
00725             AVStream *st= s->streams[i];
00726             int64_t dts_tb = av_rescale_rnd(pkt->dts,
00727                 nus->time_base->num * (int64_t)nut->stream[i].time_base->den,
00728                 nus->time_base->den * (int64_t)nut->stream[i].time_base->num,
00729                 AV_ROUND_DOWN);
00730             int index= av_index_search_timestamp(st, dts_tb, AVSEEK_FLAG_BACKWARD);
00731             if(index>=0) dummy.pos= FFMIN(dummy.pos, st->index_entries[index].pos);
00732         }
00733         if(dummy.pos == INT64_MAX)
00734             dummy.pos= 0;
00735         sp= av_tree_find(nut->syncpoints, &dummy, (void *) ff_nut_sp_pos_cmp,
00736                          NULL);
00737 
00738         nut->last_syncpoint_pos= avio_tell(bc);
00739         ret = avio_open_dyn_buf(&dyn_bc);
00740         if(ret < 0)
00741             return ret;
00742         put_tt(nut, nus->time_base, dyn_bc, pkt->dts);
00743         ff_put_v(dyn_bc, sp ? (nut->last_syncpoint_pos - sp->pos)>>4 : 0);
00744         put_packet(nut, bc, dyn_bc, 1, SYNCPOINT_STARTCODE);
00745 
00746         ff_nut_add_sp(nut, nut->last_syncpoint_pos, 0/*unused*/, pkt->dts);
00747     }
00748     assert(nus->last_pts != AV_NOPTS_VALUE);
00749 
00750     coded_pts = pkt->pts & ((1<<nus->msb_pts_shift)-1);
00751     if(ff_lsb2full(nus, coded_pts) != pkt->pts)
00752         coded_pts= pkt->pts + (1<<nus->msb_pts_shift);
00753 
00754     best_header_idx= find_best_header_idx(nut, pkt);
00755 
00756     best_length=INT_MAX;
00757     frame_code= -1;
00758     for(i=0; i<256; i++){
00759         int length= 0;
00760         FrameCode *fc= &nut->frame_code[i];
00761         int flags= fc->flags;
00762 
00763         if(flags & FLAG_INVALID)
00764             continue;
00765         needed_flags= get_needed_flags(nut, nus, fc, pkt);
00766 
00767         if(flags & FLAG_CODED){
00768             length++;
00769             flags = needed_flags;
00770         }
00771 
00772         if((flags & needed_flags) != needed_flags)
00773             continue;
00774 
00775         if((flags ^ needed_flags) & FLAG_KEY)
00776             continue;
00777 
00778         if(flags & FLAG_STREAM_ID)
00779             length+= ff_get_v_length(pkt->stream_index);
00780 
00781         if(pkt->size % fc->size_mul != fc->size_lsb)
00782             continue;
00783         if(flags & FLAG_SIZE_MSB)
00784             length += ff_get_v_length(pkt->size / fc->size_mul);
00785 
00786         if(flags & FLAG_CHECKSUM)
00787             length+=4;
00788 
00789         if(flags & FLAG_CODED_PTS)
00790             length += ff_get_v_length(coded_pts);
00791 
00792         if(   (flags & FLAG_CODED)
00793            && nut->header_len[best_header_idx] > nut->header_len[fc->header_idx]+1){
00794             flags |= FLAG_HEADER_IDX;
00795         }
00796 
00797         if(flags & FLAG_HEADER_IDX){
00798             length += 1 - nut->header_len[best_header_idx];
00799         }else{
00800             length -= nut->header_len[fc->header_idx];
00801         }
00802 
00803         length*=4;
00804         length+= !(flags & FLAG_CODED_PTS);
00805         length+= !(flags & FLAG_CHECKSUM);
00806 
00807         if(length < best_length){
00808             best_length= length;
00809             frame_code=i;
00810         }
00811     }
00812     assert(frame_code != -1);
00813     fc= &nut->frame_code[frame_code];
00814     flags= fc->flags;
00815     needed_flags= get_needed_flags(nut, nus, fc, pkt);
00816     header_idx= fc->header_idx;
00817 
00818     ffio_init_checksum(bc, ff_crc04C11DB7_update, 0);
00819     avio_w8(bc, frame_code);
00820     if(flags & FLAG_CODED){
00821         ff_put_v(bc, (flags^needed_flags) & ~(FLAG_CODED));
00822         flags = needed_flags;
00823     }
00824     if(flags & FLAG_STREAM_ID)  ff_put_v(bc, pkt->stream_index);
00825     if(flags & FLAG_CODED_PTS)  ff_put_v(bc, coded_pts);
00826     if(flags & FLAG_SIZE_MSB)   ff_put_v(bc, pkt->size / fc->size_mul);
00827     if(flags & FLAG_HEADER_IDX) ff_put_v(bc, header_idx= best_header_idx);
00828 
00829     if(flags & FLAG_CHECKSUM)   avio_wl32(bc, ffio_get_checksum(bc));
00830     else                        ffio_get_checksum(bc);
00831 
00832     avio_write(bc, pkt->data + nut->header_len[header_idx], pkt->size - nut->header_len[header_idx]);
00833     nus->last_flags= flags;
00834     nus->last_pts= pkt->pts;
00835 
00836     //FIXME just store one per syncpoint
00837     if(flags & FLAG_KEY)
00838         av_add_index_entry(
00839             s->streams[pkt->stream_index],
00840             nut->last_syncpoint_pos,
00841             pkt->pts,
00842             0,
00843             0,
00844             AVINDEX_KEYFRAME);
00845 
00846     return 0;
00847 }
00848 
00849 static int nut_write_trailer(AVFormatContext *s){
00850     NUTContext *nut= s->priv_data;
00851     AVIOContext *bc= s->pb;
00852 
00853     while(nut->header_count<3)
00854         write_headers(s, bc);
00855     avio_flush(bc);
00856     ff_nut_free_sp(nut);
00857     av_freep(&nut->stream);
00858     av_freep(&nut->chapter);
00859     av_freep(&nut->time_base);
00860 
00861     return 0;
00862 }
00863 
00864 AVOutputFormat ff_nut_muxer = {
00865     .name           = "nut",
00866     .long_name      = NULL_IF_CONFIG_SMALL("NUT format"),
00867     .mime_type      = "video/x-nut",
00868     .extensions     = "nut",
00869     .priv_data_size = sizeof(NUTContext),
00870 #if   CONFIG_LIBVORBIS
00871     .audio_codec    = CODEC_ID_VORBIS,
00872 #elif CONFIG_LIBMP3LAME
00873     .audio_codec    = CODEC_ID_MP3,
00874 #else
00875     .audio_codec    = CODEC_ID_MP2,
00876 #endif
00877     .video_codec    = CODEC_ID_MPEG4,
00878     .write_header   = nut_write_header,
00879     .write_packet   = nut_write_packet,
00880     .write_trailer  = nut_write_trailer,
00881     .flags = AVFMT_GLOBALHEADER | AVFMT_VARIABLE_FPS,
00882     .codec_tag = (const AVCodecTag * const []){ ff_codec_bmp_tags, ff_nut_video_tags, ff_codec_wav_tags, ff_nut_subtitle_tags, 0 },
00883 };