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FFmpeg/libavformat/nutenc.c

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  1. /*

  2.  * nut muxer

  3.  * Copyright (c) 2004-2007 Michael Niedermayer

  4.  *

  5.  * This file is part of Libav.

  6.  *

  7.  * Libav is free software; you can redistribute it and/or

  8.  * modify it under the terms of the GNU Lesser General Public

  9.  * License as published by the Free Software Foundation; either

  10.  * version 2.1 of the License, or (at your option) any later version.

  11.  *

  12.  * Libav is distributed in the hope that it will be useful,

  13.  * but WITHOUT ANY WARRANTY; without even the implied warranty of

  14.  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

  15.  * Lesser General Public License for more details.

  16.  *

  17.  * You should have received a copy of the GNU Lesser General Public

  18.  * License along with Libav; if not, write to the Free Software

  19.  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA

  20.  */

  21. 

  22. #include "libavutil/intreadwrite.h"

  23. #include "libavutil/mathematics.h"

  24. #include "libavutil/tree.h"

  25. #include "libavutil/dict.h"

  26. #include "libavcodec/mpegaudiodata.h"

  27. #include "nut.h"

  28. #include "internal.h"

  29. #include "avio_internal.h"

  30. 

  31. static int find_expected_header(AVCodecContext *c, int size, int key_frame,

  32.                                 uint8_t out[64])

  33. {

  34.     int sample_rate = c->sample_rate;

  35. 

  36.     if (size > 4096)

  37.         return 0;

  38. 

  39.     AV_WB24(out, 1);

  40. 

  41.     if (c->codec_id == AV_CODEC_ID_MPEG4) {

  42.         if (key_frame) {

  43.             return 3;

  44.         } else {

  45.             out[3] = 0xB6;

  46.             return 4;

  47.         }

  48.     } else if (c->codec_id == AV_CODEC_ID_MPEG1VIDEO ||

  49.                c->codec_id == AV_CODEC_ID_MPEG2VIDEO) {

  50.         return 3;

  51.     } else if (c->codec_id == AV_CODEC_ID_H264) {

  52.         return 3;

  53.     } else if (c->codec_id == AV_CODEC_ID_MP3 ||

  54.                c->codec_id == AV_CODEC_ID_MP2) {

  55.         int lsf, mpeg25, sample_rate_index, bitrate_index, frame_size;

  56.         int layer           = c->codec_id == AV_CODEC_ID_MP3 ? 3 : 2;

  57.         unsigned int header = 0xFFF00000;

  58. 

  59.         lsf           = sample_rate < (24000 + 32000) / 2;

  60.         mpeg25        = sample_rate < (12000 + 16000) / 2;

  61.         sample_rate <<= lsf + mpeg25;

  62.         if (sample_rate < (32000 + 44100) / 2)

  63.             sample_rate_index = 2;

  64.         else if (sample_rate < (44100 + 48000) / 2)

  65.             sample_rate_index = 0;

  66.         else

  67.             sample_rate_index = 1;

  68. 

  69.         sample_rate = avpriv_mpa_freq_tab[sample_rate_index] >> (lsf + mpeg25);

  70. 

  71.         for (bitrate_index = 2; bitrate_index < 30; bitrate_index++) {

  72.             frame_size =

  73.                 avpriv_mpa_bitrate_tab[lsf][layer - 1][bitrate_index >> 1];

  74.             frame_size = (frame_size * 144000) / (sample_rate << lsf) +

  75.                 (bitrate_index & 1);

  76. 

  77.             if (frame_size == size)

  78.                 break;

  79.         }

  80. 

  81.         header |= (!lsf) << 19;

  82.         header |= (4 - layer) << 17;

  83.         header |= 1 << 16; //no crc

  84.         AV_WB32(out, header);

  85.         if (size <= 0)

  86.             return 2;  //we guess there is no crc, if there is one the user clearly does not care about overhead

  87.         if (bitrate_index == 30)

  88.             return -1;  //something is wrong ...

  89. 

  90.         header |= (bitrate_index >> 1) << 12;

  91.         header |= sample_rate_index << 10;

  92.         header |= (bitrate_index & 1) << 9;

  93. 

  94.         return 2; //FIXME actually put the needed ones in build_elision_headers()

  95.         return 3; //we guess that the private bit is not set

  96. //FIXME the above assumptions should be checked, if these turn out false too often something should be done

  97.     }

  98.     return 0;

  99. }

  100. 

  101. static int find_header_idx(AVFormatContext *s, AVCodecContext *c, int size,

  102.                            int frame_type)

  103. {

  104.     NUTContext *nut = s->priv_data;

  105.     uint8_t out[64];

  106.     int i;

  107.     int len = find_expected_header(c, size, frame_type, out);

  108. 

  109.     for (i = 1; i < nut->header_count; i++) {

  110.         if (len == nut->header_len[i] && !memcmp(out, nut->header[i], len)) {

  111.             return i;

  112.         }

  113.     }

  114. 

  115.     return 0;

  116. }

  117. 

  118. static void build_elision_headers(AVFormatContext *s)

  119. {

  120.     NUTContext *nut = s->priv_data;

  121.     int i;

  122.     //FIXME this is lame

  123.     //FIXME write a 2pass mode to find the maximal headers

  124.     static const uint8_t headers[][5] = {

  125.         { 3, 0x00, 0x00, 0x01 },

  126.         { 4, 0x00, 0x00, 0x01, 0xB6},

  127.         { 2, 0xFF, 0xFA }, //mp3+crc

  128.         { 2, 0xFF, 0xFB }, //mp3

  129.         { 2, 0xFF, 0xFC }, //mp2+crc

  130.         { 2, 0xFF, 0xFD }, //mp2

  131.     };

  132. 

  133.     nut->header_count = 7;

  134.     for (i = 1; i < nut->header_count; i++) {

  135.         nut->header_len[i] = headers[i - 1][0];

  136.         nut->header[i]     = &headers[i - 1][1];

  137.     }

  138. }

  139. 

  140. static void build_frame_code(AVFormatContext *s)

  141. {

  142.     NUTContext *nut = s->priv_data;

  143.     int key_frame, index, pred, stream_id;

  144.     int start = 1;

  145.     int end   = 254;

  146.     int keyframe_0_esc = s->nb_streams > 2;

  147.     int pred_table[10];

  148.     FrameCode *ft;

  149. 

  150.     ft            = &nut->frame_code[start];

  151.     ft->flags     = FLAG_CODED;

  152.     ft->size_mul  = 1;

  153.     ft->pts_delta = 1;

  154.     start++;

  155. 

  156.     if (keyframe_0_esc) {

  157.         /* keyframe = 0 escape */

  158.         FrameCode *ft = &nut->frame_code[start];

  159.         ft->flags    = FLAG_STREAM_ID | FLAG_SIZE_MSB | FLAG_CODED_PTS;

  160.         ft->size_mul = 1;

  161.         start++;

  162.     }

  163. 

  164.     for (stream_id = 0; stream_id < s->nb_streams; stream_id++) {

  165.         int start2 = start + (end - start) * stream_id       / s->nb_streams;

  166.         int end2   = start + (end - start) * (stream_id + 1) / s->nb_streams;

  167.         AVCodecContext *codec = s->streams[stream_id]->codec;

  168.         int is_audio          = codec->codec_type == AVMEDIA_TYPE_AUDIO;

  169.         int intra_only        = /*codec->intra_only || */ is_audio;

  170.         int pred_count;

  171. 

  172.         for (key_frame = 0; key_frame < 2; key_frame++) {

  173.             if (!intra_only || !keyframe_0_esc || key_frame != 0) {

  174.                 FrameCode *ft = &nut->frame_code[start2];

  175.                 ft->flags     = FLAG_KEY * key_frame;

  176.                 ft->flags    |= FLAG_SIZE_MSB | FLAG_CODED_PTS;

  177.                 ft->stream_id = stream_id;

  178.                 ft->size_mul  = 1;

  179.                 if (is_audio)

  180.                     ft->header_idx = find_header_idx(s, codec, -1, key_frame);

  181.                 start2++;

  182.             }

  183.         }

  184. 

  185.         key_frame = intra_only;

  186.         if (is_audio) {

  187.             int frame_bytes = codec->frame_size * (int64_t)codec->bit_rate /

  188.                               (8 * codec->sample_rate);

  189.             int pts;

  190.             for (pts = 0; pts < 2; pts++)

  191.                 for (pred = 0; pred < 2; pred++) {

  192.                     FrameCode *ft = &nut->frame_code[start2];

  193.                     ft->flags      = FLAG_KEY * key_frame;

  194.                     ft->stream_id  = stream_id;

  195.                     ft->size_mul   = frame_bytes + 2;

  196.                     ft->size_lsb   = frame_bytes + pred;

  197.                     ft->pts_delta  = pts;

  198.                     ft->header_idx = find_header_idx(s, codec, frame_bytes + pred, key_frame);

  199.                     start2++;

  200.                 }

  201.         } else {

  202.             FrameCode *ft = &nut->frame_code[start2];

  203.             ft->flags     = FLAG_KEY | FLAG_SIZE_MSB;

  204.             ft->stream_id = stream_id;

  205.             ft->size_mul  = 1;

  206.             ft->pts_delta = 1;

  207.             start2++;

  208.         }

  209. 

  210.         if (codec->has_b_frames) {

  211.             pred_count    = 5;

  212.             pred_table[0] = -2;

  213.             pred_table[1] = -1;

  214.             pred_table[2] = 1;

  215.             pred_table[3] = 3;

  216.             pred_table[4] = 4;

  217.         } else if (codec->codec_id == AV_CODEC_ID_VORBIS) {

  218.             pred_count    = 3;

  219.             pred_table[0] = 2;

  220.             pred_table[1] = 9;

  221.             pred_table[2] = 16;

  222.         } else {

  223.             pred_count    = 1;

  224.             pred_table[0] = 1;

  225.         }

  226. 

  227.         for (pred = 0; pred < pred_count; pred++) {

  228.             int start3 = start2 + (end2 - start2) * pred / pred_count;

  229.             int end3   = start2 + (end2 - start2) * (pred + 1) / pred_count;

  230. 

  231.             for (index = start3; index < end3; index++) {

  232.                 FrameCode *ft = &nut->frame_code[index];

  233.                 ft->flags     = FLAG_KEY * key_frame;

  234.                 ft->flags    |= FLAG_SIZE_MSB;

  235.                 ft->stream_id = stream_id;

  236. //FIXME use single byte size and pred from last

  237.                 ft->size_mul  = end3 - start3;

  238.                 ft->size_lsb  = index - start3;

  239.                 ft->pts_delta = pred_table[pred];

  240.                 if (is_audio)

  241.                     ft->header_idx = find_header_idx(s, codec, -1, key_frame);

  242.             }

  243.         }

  244.     }

  245.     memmove(&nut->frame_code['N' + 1], &nut->frame_code['N'],

  246.             sizeof(FrameCode) * (255 - 'N'));

  247.     nut->frame_code[0].flags       =

  248.         nut->frame_code[255].flags =

  249.         nut->frame_code['N'].flags = FLAG_INVALID;

  250. }

  251. 

  252. static void put_tt(NUTContext *nut, AVRational *time_base, AVIOContext *bc,

  253.                    uint64_t val)

  254. {

  255.     val *= nut->time_base_count;

  256.     val += time_base - nut->time_base;

  257.     ff_put_v(bc, val);

  258. }

  259. /**

  260.  * Store a string as vb.

  261.  */

  262. static void put_str(AVIOContext *bc, const char *string)

  263. {

  264.     int len = strlen(string);

  265. 

  266.     ff_put_v(bc, len);

  267.     avio_write(bc, string, len);

  268. }

  269. 

  270. static void put_s(AVIOContext *bc, int64_t val)

  271. {

  272.     ff_put_v(bc, 2 * FFABS(val) - (val > 0));

  273. }

  274. 

  275. #ifdef TRACE

  276. static inline void ff_put_v_trace(AVIOContext *bc, uint64_t v, const char *file,

  277.                                   const char *func, int line)

  278. {

  279.     av_log(NULL, AV_LOG_DEBUG, "ff_put_v %5"PRId64" / %"PRIX64" in %s %s:%d\n", v, v, file, func, line);

  280. 

  281.     ff_put_v(bc, v);

  282. }

  283. 

  284. static inline void put_s_trace(AVIOContext *bc, int64_t v, const char *file,

  285.                                const char *func, int line)

  286. {

  287.     av_log(NULL, AV_LOG_DEBUG, "put_s %5"PRId64" / %"PRIX64" in %s %s:%d\n", v, v, file, func, line);

  288. 

  289.     put_s(bc, v);

  290. }

  291. #define ff_put_v(bc, v)  ff_put_v_trace(bc, v, __FILE__, __PRETTY_FUNCTION__, __LINE__)

  292. #define put_s(bc, v)  put_s_trace(bc, v, __FILE__, __PRETTY_FUNCTION__, __LINE__)

  293. #endif

  294. 

  295. //FIXME remove calculate_checksum

  296. static void put_packet(NUTContext *nut, AVIOContext *bc, AVIOContext *dyn_bc,

  297.                        int calculate_checksum, uint64_t startcode)

  298. {

  299.     uint8_t *dyn_buf = NULL;

  300.     int dyn_size     = avio_close_dyn_buf(dyn_bc, &dyn_buf);

  301.     int forw_ptr     = dyn_size + 4 * calculate_checksum;

  302. 

  303.     if (forw_ptr > 4096)

  304.         ffio_init_checksum(bc, ff_crc04C11DB7_update, 0);

  305.     avio_wb64(bc, startcode);

  306.     ff_put_v(bc, forw_ptr);

  307.     if (forw_ptr > 4096)

  308.         avio_wl32(bc, ffio_get_checksum(bc));

  309. 

  310.     if (calculate_checksum)

  311.         ffio_init_checksum(bc, ff_crc04C11DB7_update, 0);

  312.     avio_write(bc, dyn_buf, dyn_size);

  313.     if (calculate_checksum)

  314.         avio_wl32(bc, ffio_get_checksum(bc));

  315. 

  316.     av_free(dyn_buf);

  317. }

  318. 

  319. static void write_mainheader(NUTContext *nut, AVIOContext *bc)

  320. {

  321.     int i, j, tmp_pts, tmp_flags, tmp_stream, tmp_mul, tmp_size, tmp_fields,

  322.         tmp_head_idx;

  323.     int64_t tmp_match;

  324. 

  325.     ff_put_v(bc, 3); /* version */

  326.     ff_put_v(bc, nut->avf->nb_streams);

  327.     ff_put_v(bc, nut->max_distance);

  328.     ff_put_v(bc, nut->time_base_count);

  329. 

  330.     for (i = 0; i < nut->time_base_count; i++) {

  331.         ff_put_v(bc, nut->time_base[i].num);

  332.         ff_put_v(bc, nut->time_base[i].den);

  333.     }

  334. 

  335.     tmp_pts      = 0;

  336.     tmp_mul      = 1;

  337.     tmp_stream   = 0;

  338.     tmp_match    = 1 - (1LL << 62);

  339.     tmp_head_idx = 0;

  340.     for (i = 0; i < 256; ) {

  341.         tmp_fields = 0;

  342.         tmp_size   = 0;

  343. //        tmp_res=0;

  344.         if (tmp_pts != nut->frame_code[i].pts_delta)

  345.             tmp_fields = 1;

  346.         if (tmp_mul != nut->frame_code[i].size_mul)

  347.             tmp_fields = 2;

  348.         if (tmp_stream != nut->frame_code[i].stream_id)

  349.             tmp_fields = 3;

  350.         if (tmp_size != nut->frame_code[i].size_lsb)

  351.             tmp_fields = 4;

  352. //        if(tmp_res    != nut->frame_code[i].res            ) tmp_fields=5;

  353.         if (tmp_head_idx != nut->frame_code[i].header_idx)

  354.             tmp_fields = 8;

  355. 

  356.         tmp_pts    = nut->frame_code[i].pts_delta;

  357.         tmp_flags  = nut->frame_code[i].flags;

  358.         tmp_stream = nut->frame_code[i].stream_id;

  359.         tmp_mul    = nut->frame_code[i].size_mul;

  360.         tmp_size   = nut->frame_code[i].size_lsb;

  361. //        tmp_res   = nut->frame_code[i].res;

  362.         tmp_head_idx = nut->frame_code[i].header_idx;

  363. 

  364.         for (j = 0; i < 256; j++, i++) {

  365.             if (i == 'N') {

  366.                 j--;

  367.                 continue;

  368.             }

  369.             if (nut->frame_code[i].pts_delta  != tmp_pts      ||

  370.                 nut->frame_code[i].flags      != tmp_flags    ||

  371.                 nut->frame_code[i].stream_id  != tmp_stream   ||

  372.                 nut->frame_code[i].size_mul   != tmp_mul      ||

  373.                 nut->frame_code[i].size_lsb   != tmp_size + j ||

  374. //              nut->frame_code[i].res        != tmp_res      ||

  375.                 nut->frame_code[i].header_idx != tmp_head_idx)

  376.                 break;

  377.         }

  378.         if (j != tmp_mul - tmp_size)

  379.             tmp_fields = 6;

  380. 

  381.         ff_put_v(bc, tmp_flags);

  382.         ff_put_v(bc, tmp_fields);

  383.         if (tmp_fields > 0)

  384.             put_s(bc, tmp_pts);

  385.         if (tmp_fields > 1)

  386.             ff_put_v(bc, tmp_mul);

  387.         if (tmp_fields > 2)

  388.             ff_put_v(bc, tmp_stream);

  389.         if (tmp_fields > 3)

  390.             ff_put_v(bc, tmp_size);

  391.         if (tmp_fields > 4)

  392.             ff_put_v(bc, 0 /*tmp_res*/);

  393.         if (tmp_fields > 5)

  394.             ff_put_v(bc, j);

  395.         if (tmp_fields > 6)

  396.             ff_put_v(bc, tmp_match);

  397.         if (tmp_fields > 7)

  398.             ff_put_v(bc, tmp_head_idx);

  399.     }

  400.     ff_put_v(bc, nut->header_count - 1);

  401.     for (i = 1; i < nut->header_count; i++) {

  402.         ff_put_v(bc, nut->header_len[i]);

  403.         avio_write(bc, nut->header[i], nut->header_len[i]);

  404.     }

  405. }

  406. 

  407. static int write_streamheader(AVFormatContext *avctx, AVIOContext *bc,

  408.                               AVStream *st, int i)

  409. {

  410.     NUTContext *nut       = avctx->priv_data;

  411.     AVCodecContext *codec = st->codec;

  412.     unsigned codec_tag    = av_codec_get_tag(ff_nut_codec_tags, codec->codec_id);

  413. 

  414.     ff_put_v(bc, i);

  415.     switch (codec->codec_type) {

  416.     case AVMEDIA_TYPE_VIDEO:

  417.         ff_put_v(bc, 0);

  418.         break;

  419.     case AVMEDIA_TYPE_AUDIO:

  420.         ff_put_v(bc, 1);

  421.         break;

  422.     case AVMEDIA_TYPE_SUBTITLE:

  423.         ff_put_v(bc, 2);

  424.         break;

  425.     default:

  426.         ff_put_v(bc, 3);

  427.         break;

  428.     }

  429.     ff_put_v(bc, 4);

  430. 

  431.     if (!codec_tag || codec->codec_id == AV_CODEC_ID_RAWVIDEO)

  432.         codec_tag = codec->codec_tag;

  433. 

  434.     if (codec_tag) {

  435.         avio_wl32(bc, codec_tag);

  436.     } else {

  437.         av_log(avctx, AV_LOG_ERROR, "No codec tag defined for stream %d\n", i);

  438.         return AVERROR(EINVAL);

  439.     }

  440. 

  441.     ff_put_v(bc, nut->stream[i].time_base - nut->time_base);

  442.     ff_put_v(bc, nut->stream[i].msb_pts_shift);

  443.     ff_put_v(bc, nut->stream[i].max_pts_distance);

  444.     ff_put_v(bc, codec->has_b_frames);

  445.     avio_w8(bc, 0); /* flags: 0x1 - fixed_fps, 0x2 - index_present */

  446. 

  447.     ff_put_v(bc, codec->extradata_size);

  448.     avio_write(bc, codec->extradata, codec->extradata_size);

  449. 

  450.     switch (codec->codec_type) {

  451.     case AVMEDIA_TYPE_AUDIO:

  452.         ff_put_v(bc, codec->sample_rate);

  453.         ff_put_v(bc, 1);

  454.         ff_put_v(bc, codec->channels);

  455.         break;

  456.     case AVMEDIA_TYPE_VIDEO:

  457.         ff_put_v(bc, codec->width);

  458.         ff_put_v(bc, codec->height);

  459. 

  460.         if (st->sample_aspect_ratio.num <= 0 ||

  461.             st->sample_aspect_ratio.den <= 0) {

  462.             ff_put_v(bc, 0);

  463.             ff_put_v(bc, 0);

  464.         } else {

  465.             ff_put_v(bc, st->sample_aspect_ratio.num);

  466.             ff_put_v(bc, st->sample_aspect_ratio.den);

  467.         }

  468.         ff_put_v(bc, 0); /* csp type -- unknown */

  469.         break;

  470.     default:

  471.         break;

  472.     }

  473.     return 0;

  474. }

  475. 

  476. static int add_info(AVIOContext *bc, const char *type, const char *value)

  477. {

  478.     put_str(bc, type);

  479.     put_s(bc, -1);

  480.     put_str(bc, value);

  481.     return 1;

  482. }

  483. 

  484. static int write_globalinfo(NUTContext *nut, AVIOContext *bc)

  485. {

  486.     AVFormatContext *s   = nut->avf;

  487.     AVDictionaryEntry *t = NULL;

  488.     AVIOContext *dyn_bc;

  489.     uint8_t *dyn_buf = NULL;

  490.     int count        = 0, dyn_size;

  491.     int ret          = avio_open_dyn_buf(&dyn_bc);

  492.     if (ret < 0)

  493.         return ret;

  494. 

  495.     while ((t = av_dict_get(s->metadata, "", t, AV_DICT_IGNORE_SUFFIX)))

  496.         count += add_info(dyn_bc, t->key, t->value);

  497. 

  498.     ff_put_v(bc, 0); //stream_if_plus1

  499.     ff_put_v(bc, 0); //chapter_id

  500.     ff_put_v(bc, 0); //timestamp_start

  501.     ff_put_v(bc, 0); //length

  502. 

  503.     ff_put_v(bc, count);

  504. 

  505.     dyn_size = avio_close_dyn_buf(dyn_bc, &dyn_buf);

  506.     avio_write(bc, dyn_buf, dyn_size);

  507.     av_free(dyn_buf);

  508.     return 0;

  509. }

  510. 

  511. static int write_streaminfo(NUTContext *nut, AVIOContext *bc, int stream_id){

  512.     AVFormatContext *s= nut->avf;

  513.     AVStream* st = s->streams[stream_id];

  514.     AVIOContext *dyn_bc;

  515.     uint8_t *dyn_buf=NULL;

  516.     int count=0, dyn_size, i;

  517.     int ret = avio_open_dyn_buf(&dyn_bc);

  518.     if(ret < 0)

  519.         return ret;

  520. 

  521.     for (i=0; ff_nut_dispositions[i].flag; ++i) {

  522.         if (st->disposition & ff_nut_dispositions[i].flag)

  523.             count += add_info(dyn_bc, "Disposition", ff_nut_dispositions[i].str);

  524.     }

  525.     dyn_size = avio_close_dyn_buf(dyn_bc, &dyn_buf);

  526. 

  527.     if (count) {

  528.         ff_put_v(bc, stream_id + 1); //stream_id_plus1

  529.         ff_put_v(bc, 0); //chapter_id

  530.         ff_put_v(bc, 0); //timestamp_start

  531.         ff_put_v(bc, 0); //length

  532. 

  533.         ff_put_v(bc, count);

  534. 

  535.         avio_write(bc, dyn_buf, dyn_size);

  536.     }

  537. 

  538.     av_free(dyn_buf);

  539.     return count;

  540. }

  541. 

  542. static int write_chapter(NUTContext *nut, AVIOContext *bc, int id)

  543. {

  544.     AVIOContext *dyn_bc;

  545.     uint8_t *dyn_buf     = NULL;

  546.     AVDictionaryEntry *t = NULL;

  547.     AVChapter *ch        = nut->avf->chapters[id];

  548.     int ret, dyn_size, count = 0;

  549. 

  550.     ret = avio_open_dyn_buf(&dyn_bc);

  551.     if (ret < 0)

  552.         return ret;

  553. 

  554.     ff_put_v(bc, 0);                                        // stream_id_plus1

  555.     put_s(bc, id + 1);                                      // chapter_id

  556.     put_tt(nut, nut->chapter[id].time_base, bc, ch->start); // chapter_start

  557.     ff_put_v(bc, ch->end - ch->start);                      // chapter_len

  558. 

  559.     while ((t = av_dict_get(ch->metadata, "", t, AV_DICT_IGNORE_SUFFIX)))

  560.         count += add_info(dyn_bc, t->key, t->value);

  561. 

  562.     ff_put_v(bc, count);

  563. 

  564.     dyn_size = avio_close_dyn_buf(dyn_bc, &dyn_buf);

  565.     avio_write(bc, dyn_buf, dyn_size);

  566.     av_freep(&dyn_buf);

  567.     return 0;

  568. }

  569. 

  570. static int write_headers(AVFormatContext *avctx, AVIOContext *bc)

  571. {

  572.     NUTContext *nut = avctx->priv_data;

  573.     AVIOContext *dyn_bc;

  574.     int i, ret;

  575. 

  576.     ff_metadata_conv_ctx(avctx, ff_nut_metadata_conv, NULL);

  577. 

  578.     ret = avio_open_dyn_buf(&dyn_bc);

  579.     if (ret < 0)

  580.         return ret;

  581.     write_mainheader(nut, dyn_bc);

  582.     put_packet(nut, bc, dyn_bc, 1, MAIN_STARTCODE);

  583. 

  584.     for (i = 0; i < nut->avf->nb_streams; i++) {

  585.         ret = avio_open_dyn_buf(&dyn_bc);

  586.         if (ret < 0)

  587.             return ret;

  588.         ret = write_streamheader(avctx, dyn_bc, nut->avf->streams[i], i);

  589.         if (ret < 0)

  590.             return ret;

  591.         put_packet(nut, bc, dyn_bc, 1, STREAM_STARTCODE);

  592.     }

  593. 

  594.     ret = avio_open_dyn_buf(&dyn_bc);

  595.     if (ret < 0)

  596.         return ret;

  597.     write_globalinfo(nut, dyn_bc);

  598.     put_packet(nut, bc, dyn_bc, 1, INFO_STARTCODE);

  599. 

  600.     for (i = 0; i < nut->avf->nb_streams; i++) {

  601.         ret = avio_open_dyn_buf(&dyn_bc);

  602.         if (ret < 0)

  603.             return ret;

  604.         ret = write_streaminfo(nut, dyn_bc, i);

  605.         if (ret < 0)

  606.             return ret;

  607.         if (ret > 0)

  608.             put_packet(nut, bc, dyn_bc, 1, INFO_STARTCODE);

  609.         else {

  610.             uint8_t *buf;

  611.             avio_close_dyn_buf(dyn_bc, &buf);

  612.             av_free(buf);

  613.         }

  614.     }

  615. 

  616.     for (i = 0; i < nut->avf->nb_chapters; i++) {

  617.         ret = avio_open_dyn_buf(&dyn_bc);

  618.         if (ret < 0)

  619.             return ret;

  620.         ret = write_chapter(nut, dyn_bc, i);

  621.         if (ret < 0) {

  622.             uint8_t *buf;

  623.             avio_close_dyn_buf(dyn_bc, &buf);

  624.             av_freep(&buf);

  625.             return ret;

  626.         }

  627.         put_packet(nut, bc, dyn_bc, 1, INFO_STARTCODE);

  628.     }

  629. 

  630.     nut->last_syncpoint_pos = INT_MIN;

  631.     nut->header_count++;

  632.     return 0;

  633. }

  634. 

  635. static int nut_write_header(AVFormatContext *s)

  636. {

  637.     NUTContext *nut = s->priv_data;

  638.     AVIOContext *bc = s->pb;

  639.     int i, j, ret;

  640. 

  641.     nut->avf = s;

  642. 

  643.     nut->stream = av_mallocz(sizeof(StreamContext) * s->nb_streams);

  644.     if (s->nb_chapters)

  645.         nut->chapter = av_mallocz(sizeof(ChapterContext) * s->nb_chapters);

  646.     nut->time_base = av_mallocz(sizeof(AVRational) * (s->nb_streams +

  647.                                                       s->nb_chapters));

  648.     if (!nut->stream || (s->nb_chapters && !nut->chapter) || !nut->time_base) {

  649.         av_freep(&nut->stream);

  650.         av_freep(&nut->chapter);

  651.         av_freep(&nut->time_base);

  652.         return AVERROR(ENOMEM);

  653.     }

  654. 

  655.     for (i = 0; i < s->nb_streams; i++) {

  656.         AVStream *st = s->streams[i];

  657.         int ssize;

  658.         AVRational time_base;

  659.         ff_parse_specific_params(st->codec, &time_base.den, &ssize,

  660.                                  &time_base.num);

  661. 

  662.         avpriv_set_pts_info(st, 64, time_base.num, time_base.den);

  663. 

  664.         for (j = 0; j < nut->time_base_count; j++)

  665.             if (!memcmp(&time_base, &nut->time_base[j], sizeof(AVRational))) {

  666.                 break;

  667.             }

  668.         nut->time_base[j]        = time_base;

  669.         nut->stream[i].time_base = &nut->time_base[j];

  670.         if (j == nut->time_base_count)

  671.             nut->time_base_count++;

  672. 

  673.         if (INT64_C(1000) * time_base.num >= time_base.den)

  674.             nut->stream[i].msb_pts_shift = 7;

  675.         else

  676.             nut->stream[i].msb_pts_shift = 14;

  677.         nut->stream[i].max_pts_distance =

  678.             FFMAX(time_base.den, time_base.num) / time_base.num;

  679.     }

  680. 

  681.     for (i = 0; i < s->nb_chapters; i++) {

  682.         AVChapter *ch = s->chapters[i];

  683. 

  684.         for (j = 0; j < nut->time_base_count; j++)

  685.             if (!memcmp(&ch->time_base, &nut->time_base[j], sizeof(AVRational)))

  686.                 break;

  687. 

  688.         nut->time_base[j]         = ch->time_base;

  689.         nut->chapter[i].time_base = &nut->time_base[j];

  690.         if (j == nut->time_base_count)

  691.             nut->time_base_count++;

  692.     }

  693. 

  694.     nut->max_distance = MAX_DISTANCE;

  695.     build_elision_headers(s);

  696.     build_frame_code(s);

  697.     assert(nut->frame_code['N'].flags == FLAG_INVALID);

  698. 

  699.     avio_write(bc, ID_STRING, strlen(ID_STRING));

  700.     avio_w8(bc, 0);

  701. 

  702.     if ((ret = write_headers(s, bc)) < 0)

  703.         return ret;

  704. 

  705.     avio_flush(bc);

  706. 

  707.     //FIXME index

  708. 

  709.     return 0;

  710. }

  711. 

  712. static int get_needed_flags(NUTContext *nut, StreamContext *nus, FrameCode *fc,

  713.                             AVPacket *pkt)

  714. {

  715.     int flags = 0;

  716. 

  717.     if (pkt->flags & AV_PKT_FLAG_KEY)

  718.         flags |= FLAG_KEY;

  719.     if (pkt->stream_index != fc->stream_id)

  720.         flags |= FLAG_STREAM_ID;

  721.     if (pkt->size / fc->size_mul)

  722.         flags |= FLAG_SIZE_MSB;

  723.     if (pkt->pts - nus->last_pts != fc->pts_delta)

  724.         flags |= FLAG_CODED_PTS;

  725.     if (pkt->size > 2 * nut->max_distance)

  726.         flags |= FLAG_CHECKSUM;

  727.     if (FFABS(pkt->pts - nus->last_pts) > nus->max_pts_distance)

  728.         flags |= FLAG_CHECKSUM;

  729.     if (pkt->size < nut->header_len[fc->header_idx] ||

  730.         (pkt->size > 4096 && fc->header_idx)        ||

  731.         memcmp(pkt->data, nut->header[fc->header_idx],

  732.                nut->header_len[fc->header_idx]))

  733.         flags |= FLAG_HEADER_IDX;

  734. 

  735.     return flags | (fc->flags & FLAG_CODED);

  736. }

  737. 

  738. static int find_best_header_idx(NUTContext *nut, AVPacket *pkt)

  739. {

  740.     int i;

  741.     int best_i   = 0;

  742.     int best_len = 0;

  743. 

  744.     if (pkt->size > 4096)

  745.         return 0;

  746. 

  747.     for (i = 1; i < nut->header_count; i++)

  748.         if (pkt->size >= nut->header_len[i]

  749.             && nut->header_len[i] > best_len

  750.             && !memcmp(pkt->data, nut->header[i], nut->header_len[i])) {

  751.             best_i   = i;

  752.             best_len = nut->header_len[i];

  753.         }

  754.     return best_i;

  755. }

  756. 

  757. static int nut_write_packet(AVFormatContext *s, AVPacket *pkt)

  758. {

  759.     NUTContext *nut    = s->priv_data;

  760.     StreamContext *nus = &nut->stream[pkt->stream_index];

  761.     AVIOContext *bc    = s->pb, *dyn_bc;

  762.     FrameCode *fc;

  763.     int64_t coded_pts;

  764.     int best_length, frame_code, flags, needed_flags, i, header_idx,

  765.         best_header_idx;

  766.     int key_frame = !!(pkt->flags & AV_PKT_FLAG_KEY);

  767.     int store_sp  = 0;

  768.     int ret;

  769. 

  770.     if (pkt->pts < 0) {

  771.         av_log(s, AV_LOG_ERROR,

  772.                "Negative pts not supported stream %d, pts %"PRId64"\n",

  773.                pkt->stream_index, pkt->pts);

  774.         return AVERROR_INVALIDDATA;

  775.     }

  776. 

  777.     if (1LL << (20 + 3 * nut->header_count) <= avio_tell(bc))

  778.         write_headers(s, bc);

  779. 

  780.     if (key_frame && !(nus->last_flags & FLAG_KEY))

  781.         store_sp = 1;

  782. 

  783.     if (pkt->size + 30 /*FIXME check*/ + avio_tell(bc) >=

  784.         nut->last_syncpoint_pos + nut->max_distance)

  785.         store_sp = 1;

  786. 

  787. //FIXME: Ensure store_sp is 1 in the first place.

  788. 

  789.     if (store_sp) {

  790.         Syncpoint *sp, dummy = { .pos = INT64_MAX };

  791. 

  792.         ff_nut_reset_ts(nut, *nus->time_base, pkt->dts);

  793.         for (i = 0; i < s->nb_streams; i++) {

  794.             AVStream *st   = s->streams[i];

  795.             int64_t dts_tb = av_rescale_rnd(pkt->dts,

  796.                 nus->time_base->num * (int64_t)nut->stream[i].time_base->den,

  797.                 nus->time_base->den * (int64_t)nut->stream[i].time_base->num,

  798.                 AV_ROUND_DOWN);

  799.             int index = av_index_search_timestamp(st, dts_tb,

  800.                                                   AVSEEK_FLAG_BACKWARD);

  801.             if (index >= 0)

  802.                 dummy.pos = FFMIN(dummy.pos, st->index_entries[index].pos);

  803.         }

  804.         if (dummy.pos == INT64_MAX)

  805.             dummy.pos = 0;

  806.         sp = av_tree_find(nut->syncpoints, &dummy, (void *)ff_nut_sp_pos_cmp,

  807.                           NULL);

  808. 

  809.         nut->last_syncpoint_pos = avio_tell(bc);

  810.         ret                     = avio_open_dyn_buf(&dyn_bc);

  811.         if (ret < 0)

  812.             return ret;

  813.         put_tt(nut, nus->time_base, dyn_bc, pkt->dts);

  814.         ff_put_v(dyn_bc, sp ? (nut->last_syncpoint_pos - sp->pos) >> 4 : 0);

  815.         put_packet(nut, bc, dyn_bc, 1, SYNCPOINT_STARTCODE);

  816. 

  817.         ff_nut_add_sp(nut, nut->last_syncpoint_pos, 0 /*unused*/, pkt->dts);

  818.     }

  819.     assert(nus->last_pts != AV_NOPTS_VALUE);

  820. 

  821.     coded_pts = pkt->pts & ((1 << nus->msb_pts_shift) - 1);

  822.     if (ff_lsb2full(nus, coded_pts) != pkt->pts)

  823.         coded_pts = pkt->pts + (1 << nus->msb_pts_shift);

  824. 

  825.     best_header_idx = find_best_header_idx(nut, pkt);

  826. 

  827.     best_length = INT_MAX;

  828.     frame_code  = -1;

  829.     for (i = 0; i < 256; i++) {

  830.         int length    = 0;

  831.         FrameCode *fc = &nut->frame_code[i];

  832.         int flags     = fc->flags;

  833. 

  834.         if (flags & FLAG_INVALID)

  835.             continue;

  836.         needed_flags = get_needed_flags(nut, nus, fc, pkt);

  837. 

  838.         if (flags & FLAG_CODED) {

  839.             length++;

  840.             flags = needed_flags;

  841.         }

  842. 

  843.         if ((flags & needed_flags) != needed_flags)

  844.             continue;

  845. 

  846.         if ((flags ^ needed_flags) & FLAG_KEY)

  847.             continue;

  848. 

  849.         if (flags & FLAG_STREAM_ID)

  850.             length += ff_get_v_length(pkt->stream_index);

  851. 

  852.         if (pkt->size % fc->size_mul != fc->size_lsb)

  853.             continue;

  854.         if (flags & FLAG_SIZE_MSB)

  855.             length += ff_get_v_length(pkt->size / fc->size_mul);

  856. 

  857.         if (flags & FLAG_CHECKSUM)

  858.             length += 4;

  859. 

  860.         if (flags & FLAG_CODED_PTS)

  861.             length += ff_get_v_length(coded_pts);

  862. 

  863.         if ((flags & FLAG_CODED)

  864.             && nut->header_len[best_header_idx] >

  865.             nut->header_len[fc->header_idx] + 1) {

  866.             flags |= FLAG_HEADER_IDX;

  867.         }

  868. 

  869.         if (flags & FLAG_HEADER_IDX) {

  870.             length += 1 - nut->header_len[best_header_idx];

  871.         } else {

  872.             length -= nut->header_len[fc->header_idx];

  873.         }

  874. 

  875.         length *= 4;

  876.         length += !(flags & FLAG_CODED_PTS);

  877.         length += !(flags & FLAG_CHECKSUM);

  878. 

  879.         if (length < best_length) {

  880.             best_length = length;

  881.             frame_code  = i;

  882.         }

  883.     }

  884.     assert(frame_code != -1);

  885.     fc           = &nut->frame_code[frame_code];

  886.     flags        = fc->flags;

  887.     needed_flags = get_needed_flags(nut, nus, fc, pkt);

  888.     header_idx   = fc->header_idx;

  889. 

  890.     ffio_init_checksum(bc, ff_crc04C11DB7_update, 0);

  891.     avio_w8(bc, frame_code);

  892.     if (flags & FLAG_CODED) {

  893.         ff_put_v(bc, (flags ^ needed_flags) & ~(FLAG_CODED));

  894.         flags = needed_flags;

  895.     }

  896.     if (flags & FLAG_STREAM_ID)

  897.         ff_put_v(bc, pkt->stream_index);

  898.     if (flags & FLAG_CODED_PTS)

  899.         ff_put_v(bc, coded_pts);

  900.     if (flags & FLAG_SIZE_MSB)

  901.         ff_put_v(bc, pkt->size / fc->size_mul);

  902.     if (flags & FLAG_HEADER_IDX)

  903.         ff_put_v(bc, header_idx = best_header_idx);

  904. 

  905.     if (flags & FLAG_CHECKSUM)

  906.         avio_wl32(bc, ffio_get_checksum(bc));

  907.     else

  908.         ffio_get_checksum(bc);

  909. 

  910.     avio_write(bc, pkt->data + nut->header_len[header_idx],

  911.                pkt->size - nut->header_len[header_idx]);

  912.     nus->last_flags = flags;

  913.     nus->last_pts   = pkt->pts;

  914. 

  915.     //FIXME just store one per syncpoint

  916.     if (flags & FLAG_KEY)

  917.         av_add_index_entry(

  918.             s->streams[pkt->stream_index],

  919.             nut->last_syncpoint_pos,

  920.             pkt->pts,

  921.             0,

  922.             0,

  923.             AVINDEX_KEYFRAME);

  924. 

  925.     return 0;

  926. }

  927. 

  928. static int nut_write_trailer(AVFormatContext *s)

  929. {

  930.     NUTContext *nut = s->priv_data;

  931.     AVIOContext *bc = s->pb;

  932. 

  933.     while (nut->header_count < 3)

  934.         write_headers(s, bc);

  935. 

  936.     ff_nut_free_sp(nut);

  937.     av_freep(&nut->stream);

  938.     av_freep(&nut->chapter);

  939.     av_freep(&nut->time_base);

  940. 

  941.     return 0;

  942. }

  943. 

  944. AVOutputFormat ff_nut_muxer = {

  945.     .name           = "nut",

  946.     .long_name      = NULL_IF_CONFIG_SMALL("NUT"),

  947.     .mime_type      = "video/x-nut",

  948.     .extensions     = "nut",

  949.     .priv_data_size = sizeof(NUTContext),

  950.     .audio_codec    = CONFIG_LIBVORBIS ? AV_CODEC_ID_VORBIS :

  951.                       CONFIG_LIBMP3LAME ? AV_CODEC_ID_MP3 : AV_CODEC_ID_MP2,

  952.     .video_codec    = AV_CODEC_ID_MPEG4,

  953.     .write_header   = nut_write_header,

  954.     .write_packet   = nut_write_packet,

  955.     .write_trailer  = nut_write_trailer,

  956.     .flags          = AVFMT_GLOBALHEADER | AVFMT_VARIABLE_FPS,

  957.     .codec_tag      = ff_nut_codec_tags,

  958. };