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  1. /*
  2.  * MPEG-DASH ISO BMFF segmenter
  3.  * Copyright (c) 2014 Martin Storsjo
  4.  *
  5.  * This file is part of FFmpeg.
  6.  *
  7.  * FFmpeg 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.  * FFmpeg 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 FFmpeg; if not, write to the Free Software
  19.  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  20.  */
  21.  
  22. #include "config.h"
  23. #if HAVE_UNISTD_H
  24. #include <unistd.h>
  25. #endif
  26.  
  27. #include "libavutil/avstring.h"
  28. #include "libavutil/intreadwrite.h"
  29. #include "libavutil/mathematics.h"
  30. #include "libavutil/opt.h"
  31. #include "libavutil/time_internal.h"
  32.  
  33. #include "avc.h"
  34. #include "avformat.h"
  35. #include "avio_internal.h"
  36. #include "internal.h"
  37. #include "isom.h"
  38. #include "os_support.h"
  39. #include "url.h"
  40.  
  41. // See ISO/IEC 23009-1:2014 5.3.9.4.4
  42. typedef enum {
  43.     DASH_TMPL_ID_UNDEFINED = -1,
  44.     DASH_TMPL_ID_ESCAPE,
  45.     DASH_TMPL_ID_REP_ID,
  46.     DASH_TMPL_ID_NUMBER,
  47.     DASH_TMPL_ID_BANDWIDTH,
  48.     DASH_TMPL_ID_TIME,
  49. } DASHTmplId;
  50.  
  51. typedef struct Segment {
  52.     char file[1024];
  53.     int64_t start_pos;
  54.     int range_length, index_length;
  55.     int64_t time;
  56.     int duration;
  57.     int n;
  58. } Segment;
  59.  
  60. typedef struct OutputStream {
  61.     AVFormatContext *ctx;
  62.     int ctx_inited;
  63.     uint8_t iobuf[32768];
  64.     URLContext *out;
  65.     int packets_written;
  66.     char initfile[1024];
  67.     int64_t init_start_pos;
  68.     int init_range_length;
  69.     int nb_segments, segments_size, segment_index;
  70.     Segment **segments;
  71.     int64_t first_pts, start_pts, max_pts;
  72.     int64_t last_dts;
  73.     int bit_rate;
  74.     char bandwidth_str[64];
  75.  
  76.     char codec_str[100];
  77. } OutputStream;
  78.  
  79. typedef struct DASHContext {
  80.     const AVClass *class;  /* Class for private options. */
  81.     int window_size;
  82.     int extra_window_size;
  83.     int min_seg_duration;
  84.     int remove_at_exit;
  85.     int use_template;
  86.     int use_timeline;
  87.     int single_file;
  88.     OutputStream *streams;
  89.     int has_video, has_audio;
  90.     int64_t last_duration;
  91.     int64_t total_duration;
  92.     char availability_start_time[100];
  93.     char dirname[1024];
  94.     const char *single_file_name;
  95.     const char *init_seg_name;
  96.     const char *media_seg_name;
  97. } DASHContext;
  98.  
  99. static int dash_write(void *opaque, uint8_t *buf, int buf_size)
  100. {
  101.     OutputStream *os = opaque;
  102.     if (os->out)
  103.         ffurl_write(os->out, buf, buf_size);
  104.     return buf_size;
  105. }
  106.  
  107. // RFC 6381
  108. static void set_codec_str(AVFormatContext *s, AVCodecContext *codec,
  109.                           char *str, int size)
  110. {
  111.     const AVCodecTag *tags[2] = { NULL, NULL };
  112.     uint32_t tag;
  113.     if (codec->codec_type == AVMEDIA_TYPE_VIDEO)
  114.         tags[0] = ff_codec_movvideo_tags;
  115.     else if (codec->codec_type == AVMEDIA_TYPE_AUDIO)
  116.         tags[0] = ff_codec_movaudio_tags;
  117.     else
  118.         return;
  119.  
  120.     tag = av_codec_get_tag(tags, codec->codec_id);
  121.     if (!tag)
  122.         return;
  123.     if (size < 5)
  124.         return;
  125.  
  126.     AV_WL32(str, tag);
  127.     str[4] = '\0';
  128.     if (!strcmp(str, "mp4a") || !strcmp(str, "mp4v")) {
  129.         uint32_t oti;
  130.         tags[0] = ff_mp4_obj_type;
  131.         oti = av_codec_get_tag(tags, codec->codec_id);
  132.         if (oti)
  133.             av_strlcatf(str, size, ".%02x", oti);
  134.         else
  135.             return;
  136.  
  137.         if (tag == MKTAG('m', 'p', '4', 'a')) {
  138.             if (codec->extradata_size >= 2) {
  139.                 int aot = codec->extradata[0] >> 3;
  140.                 if (aot == 31)
  141.                     aot = ((AV_RB16(codec->extradata) >> 5) & 0x3f) + 32;
  142.                 av_strlcatf(str, size, ".%d", aot);
  143.             }
  144.         } else if (tag == MKTAG('m', 'p', '4', 'v')) {
  145.             // Unimplemented, should output ProfileLevelIndication as a decimal number
  146.             av_log(s, AV_LOG_WARNING, "Incomplete RFC 6381 codec string for mp4v\n");
  147.         }
  148.     } else if (!strcmp(str, "avc1")) {
  149.         uint8_t *tmpbuf = NULL;
  150.         uint8_t *extradata = codec->extradata;
  151.         int extradata_size = codec->extradata_size;
  152.         if (!extradata_size)
  153.             return;
  154.         if (extradata[0] != 1) {
  155.             AVIOContext *pb;
  156.             if (avio_open_dyn_buf(&pb) < 0)
  157.                 return;
  158.             if (ff_isom_write_avcc(pb, extradata, extradata_size) < 0) {
  159.                 ffio_free_dyn_buf(&pb);
  160.                 return;
  161.             }
  162.             extradata_size = avio_close_dyn_buf(pb, &extradata);
  163.             tmpbuf = extradata;
  164.         }
  165.  
  166.         if (extradata_size >= 4)
  167.             av_strlcatf(str, size, ".%02x%02x%02x",
  168.                         extradata[1], extradata[2], extradata[3]);
  169.         av_free(tmpbuf);
  170.     }
  171. }
  172.  
  173. static void dash_free(AVFormatContext *s)
  174. {
  175.     DASHContext *c = s->priv_data;
  176.     int i, j;
  177.     if (!c->streams)
  178.         return;
  179.     for (i = 0; i < s->nb_streams; i++) {
  180.         OutputStream *os = &c->streams[i];
  181.         if (os->ctx && os->ctx_inited)
  182.             av_write_trailer(os->ctx);
  183.         if (os->ctx && os->ctx->pb)
  184.             av_free(os->ctx->pb);
  185.         ffurl_close(os->out);
  186.         os->out =  NULL;
  187.         if (os->ctx)
  188.             avformat_free_context(os->ctx);
  189.         for (j = 0; j < os->nb_segments; j++)
  190.             av_free(os->segments[j]);
  191.         av_free(os->segments);
  192.     }
  193.     av_freep(&c->streams);
  194. }
  195.  
  196. static void output_segment_list(OutputStream *os, AVIOContext *out, DASHContext *c)
  197. {
  198.     int i, start_index = 0, start_number = 1;
  199.     if (c->window_size) {
  200.         start_index  = FFMAX(os->nb_segments   - c->window_size, 0);
  201.         start_number = FFMAX(os->segment_index - c->window_size, 1);
  202.     }
  203.  
  204.     if (c->use_template) {
  205.         int timescale = c->use_timeline ? os->ctx->streams[0]->time_base.den : AV_TIME_BASE;
  206.         avio_printf(out, "\t\t\t\t<SegmentTemplate timescale=\"%d\" ", timescale);
  207.         if (!c->use_timeline)
  208.             avio_printf(out, "duration=\"%"PRId64"\" ", c->last_duration);
  209.         avio_printf(out, "initialization=\"%s\" media=\"%s\" startNumber=\"%d\">\n", c->init_seg_name, c->media_seg_name, c->use_timeline ? start_number : 1);
  210.         if (c->use_timeline) {
  211.             int64_t cur_time = 0;
  212.             avio_printf(out, "\t\t\t\t\t<SegmentTimeline>\n");
  213.             for (i = start_index; i < os->nb_segments; ) {
  214.                 Segment *seg = os->segments[i];
  215.                 int repeat = 0;
  216.                 avio_printf(out, "\t\t\t\t\t\t<S ");
  217.                 if (i == start_index || seg->time != cur_time) {
  218.                     cur_time = seg->time;
  219.                     avio_printf(out, "t=\"%"PRId64"\" ", seg->time);
  220.                 }
  221.                 avio_printf(out, "d=\"%d\" ", seg->duration);
  222.                 while (i + repeat + 1 < os->nb_segments &&
  223.                        os->segments[i + repeat + 1]->duration == seg->duration &&
  224.                        os->segments[i + repeat + 1]->time == os->segments[i + repeat]->time + os->segments[i + repeat]->duration)
  225.                     repeat++;
  226.                 if (repeat > 0)
  227.                     avio_printf(out, "r=\"%d\" ", repeat);
  228.                 avio_printf(out, "/>\n");
  229.                 i += 1 + repeat;
  230.                 cur_time += (1 + repeat) * seg->duration;
  231.             }
  232.             avio_printf(out, "\t\t\t\t\t</SegmentTimeline>\n");
  233.         }
  234.         avio_printf(out, "\t\t\t\t</SegmentTemplate>\n");
  235.     } else if (c->single_file) {
  236.         avio_printf(out, "\t\t\t\t<BaseURL>%s</BaseURL>\n", os->initfile);
  237.         avio_printf(out, "\t\t\t\t<SegmentList timescale=\"%d\" duration=\"%"PRId64"\" startNumber=\"%d\">\n", AV_TIME_BASE, c->last_duration, start_number);
  238.         avio_printf(out, "\t\t\t\t\t<Initialization range=\"%"PRId64"-%"PRId64"\" />\n", os->init_start_pos, os->init_start_pos + os->init_range_length - 1);
  239.         for (i = start_index; i < os->nb_segments; i++) {
  240.             Segment *seg = os->segments[i];
  241.             avio_printf(out, "\t\t\t\t\t<SegmentURL mediaRange=\"%"PRId64"-%"PRId64"\" ", seg->start_pos, seg->start_pos + seg->range_length - 1);
  242.             if (seg->index_length)
  243.                 avio_printf(out, "indexRange=\"%"PRId64"-%"PRId64"\" ", seg->start_pos, seg->start_pos + seg->index_length - 1);
  244.             avio_printf(out, "/>\n");
  245.         }
  246.         avio_printf(out, "\t\t\t\t</SegmentList>\n");
  247.     } else {
  248.         avio_printf(out, "\t\t\t\t<SegmentList timescale=\"%d\" duration=\"%"PRId64"\" startNumber=\"%d\">\n", AV_TIME_BASE, c->last_duration, start_number);
  249.         avio_printf(out, "\t\t\t\t\t<Initialization sourceURL=\"%s\" />\n", os->initfile);
  250.         for (i = start_index; i < os->nb_segments; i++) {
  251.             Segment *seg = os->segments[i];
  252.             avio_printf(out, "\t\t\t\t\t<SegmentURL media=\"%s\" />\n", seg->file);
  253.         }
  254.         avio_printf(out, "\t\t\t\t</SegmentList>\n");
  255.     }
  256. }
  257.  
  258. static DASHTmplId dash_read_tmpl_id(const char *identifier, char *format_tag,
  259.                                     size_t format_tag_size, const char **ptr) {
  260.     const char *next_ptr;
  261.     DASHTmplId id_type = DASH_TMPL_ID_UNDEFINED;
  262.  
  263.     if (av_strstart(identifier, "$$", &next_ptr)) {
  264.         id_type = DASH_TMPL_ID_ESCAPE;
  265.         *ptr = next_ptr;
  266.     } else if (av_strstart(identifier, "$RepresentationID$", &next_ptr)) {
  267.         id_type = DASH_TMPL_ID_REP_ID;
  268.         // default to basic format, as $RepresentationID$ identifiers
  269.         // are not allowed to have custom format-tags.
  270.         av_strlcpy(format_tag, "%d", format_tag_size);
  271.         *ptr = next_ptr;
  272.     } else { // the following identifiers may have an explicit format_tag
  273.         if (av_strstart(identifier, "$Number", &next_ptr))
  274.             id_type = DASH_TMPL_ID_NUMBER;
  275.         else if (av_strstart(identifier, "$Bandwidth", &next_ptr))
  276.             id_type = DASH_TMPL_ID_BANDWIDTH;
  277.         else if (av_strstart(identifier, "$Time", &next_ptr))
  278.             id_type = DASH_TMPL_ID_TIME;
  279.         else
  280.             id_type = DASH_TMPL_ID_UNDEFINED;
  281.  
  282.         // next parse the dash format-tag and generate a c-string format tag
  283.         // (next_ptr now points at the first '%' at the beginning of the format-tag)
  284.         if (id_type != DASH_TMPL_ID_UNDEFINED) {
  285.             const char *number_format = (id_type == DASH_TMPL_ID_TIME) ? PRId64 : "d";
  286.             if (next_ptr[0] == '$') { // no dash format-tag
  287.                 snprintf(format_tag, format_tag_size, "%%%s", number_format);
  288.                 *ptr = &next_ptr[1];
  289.             } else {
  290.                 const char *width_ptr;
  291.                 // only tolerate single-digit width-field (i.e. up to 9-digit width)
  292.                 if (av_strstart(next_ptr, "%0", &width_ptr) &&
  293.                     av_isdigit(width_ptr[0]) &&
  294.                     av_strstart(&width_ptr[1], "d$", &next_ptr)) {
  295.                     // yes, we're using a format tag to build format_tag.
  296.                     snprintf(format_tag, format_tag_size, "%s%c%s", "%0", width_ptr[0], number_format);
  297.                     *ptr = next_ptr;
  298.                 } else {
  299.                     av_log(NULL, AV_LOG_WARNING, "Failed to parse format-tag beginning with %s. Expected either a "
  300.                                                  "closing '$' character or a format-string like '%%0[width]d', "
  301.                                                  "where width must be a single digit\n", next_ptr);
  302.                     id_type = DASH_TMPL_ID_UNDEFINED;
  303.                 }
  304.             }
  305.         }
  306.     }
  307.     return id_type;
  308. }
  309.  
  310. static void dash_fill_tmpl_params(char *dst, size_t buffer_size,
  311.                                   const char *template, int rep_id,
  312.                                   int number, int bit_rate,
  313.                                   int64_t time) {
  314.     int dst_pos = 0;
  315.     const char *t_cur = template;
  316.     while (dst_pos < buffer_size - 1 && *t_cur) {
  317.         char format_tag[7]; // May be "%d", "%0Xd", or "%0Xlld" (for $Time$), where X is in [0-9]
  318.         int n = 0;
  319.         DASHTmplId id_type;
  320.         const char *t_next = strchr(t_cur, '$'); // copy over everything up to the first '$' character
  321.         if (t_next) {
  322.             int num_copy_bytes = FFMIN(t_next - t_cur, buffer_size - dst_pos - 1);
  323.             av_strlcpy(&dst[dst_pos], t_cur, num_copy_bytes + 1);
  324.             // advance
  325.             dst_pos += num_copy_bytes;
  326.             t_cur = t_next;
  327.         } else { // no more DASH identifiers to substitute - just copy the rest over and break
  328.             av_strlcpy(&dst[dst_pos], t_cur, buffer_size - dst_pos);
  329.             break;
  330.         }
  331.  
  332.         if (dst_pos >= buffer_size - 1 || !*t_cur)
  333.             break;
  334.  
  335.         // t_cur is now pointing to a '$' character
  336.         id_type = dash_read_tmpl_id(t_cur, format_tag, sizeof(format_tag), &t_next);
  337.         switch (id_type) {
  338.         case DASH_TMPL_ID_ESCAPE:
  339.             av_strlcpy(&dst[dst_pos], "$", 2);
  340.             n = 1;
  341.             break;
  342.         case DASH_TMPL_ID_REP_ID:
  343.             n = snprintf(&dst[dst_pos], buffer_size - dst_pos, format_tag, rep_id);
  344.             break;
  345.         case DASH_TMPL_ID_NUMBER:
  346.             n = snprintf(&dst[dst_pos], buffer_size - dst_pos, format_tag, number);
  347.             break;
  348.         case DASH_TMPL_ID_BANDWIDTH:
  349.             n = snprintf(&dst[dst_pos], buffer_size - dst_pos, format_tag, bit_rate);
  350.             break;
  351.         case DASH_TMPL_ID_TIME:
  352.             n = snprintf(&dst[dst_pos], buffer_size - dst_pos, format_tag, time);
  353.             break;
  354.         case DASH_TMPL_ID_UNDEFINED:
  355.             // copy over one byte and advance
  356.             av_strlcpy(&dst[dst_pos], t_cur, 2);
  357.             n = 1;
  358.             t_next = &t_cur[1];
  359.             break;
  360.         }
  361.         // t_next points just past the processed identifier
  362.         // n is the number of bytes that were attempted to be written to dst
  363.         // (may have failed to write all because buffer_size).
  364.  
  365.         // advance
  366.         dst_pos += FFMIN(n, buffer_size - dst_pos - 1);
  367.         t_cur = t_next;
  368.     }
  369. }
  370.  
  371. static char *xmlescape(const char *str) {
  372.     int outlen = strlen(str)*3/2 + 6;
  373.     char *out = av_realloc(NULL, outlen + 1);
  374.     int pos = 0;
  375.     if (!out)
  376.         return NULL;
  377.     for (; *str; str++) {
  378.         if (pos + 6 > outlen) {
  379.             char *tmp;
  380.             outlen = 2 * outlen + 6;
  381.             tmp = av_realloc(out, outlen + 1);
  382.             if (!tmp) {
  383.                 av_free(out);
  384.                 return NULL;
  385.             }
  386.             out = tmp;
  387.         }
  388.         if (*str == '&') {
  389.             memcpy(&out[pos], "&amp;", 5);
  390.             pos += 5;
  391.         } else if (*str == '<') {
  392.             memcpy(&out[pos], "&lt;", 4);
  393.             pos += 4;
  394.         } else if (*str == '>') {
  395.             memcpy(&out[pos], "&gt;", 4);
  396.             pos += 4;
  397.         } else if (*str == '\'') {
  398.             memcpy(&out[pos], "&apos;", 6);
  399.             pos += 6;
  400.         } else if (*str == '\"') {
  401.             memcpy(&out[pos], "&quot;", 6);
  402.             pos += 6;
  403.         } else {
  404.             out[pos++] = *str;
  405.         }
  406.     }
  407.     out[pos] = '\0';
  408.     return out;
  409. }
  410.  
  411. static void write_time(AVIOContext *out, int64_t time)
  412. {
  413.     int seconds = time / AV_TIME_BASE;
  414.     int fractions = time % AV_TIME_BASE;
  415.     int minutes = seconds / 60;
  416.     int hours = minutes / 60;
  417.     seconds %= 60;
  418.     minutes %= 60;
  419.     avio_printf(out, "PT");
  420.     if (hours)
  421.         avio_printf(out, "%dH", hours);
  422.     if (hours || minutes)
  423.         avio_printf(out, "%dM", minutes);
  424.     avio_printf(out, "%d.%dS", seconds, fractions / (AV_TIME_BASE / 10));
  425. }
  426.  
  427. static void format_date_now(char *buf, int size)
  428. {
  429.     time_t t = time(NULL);
  430.     struct tm *ptm, tmbuf;
  431.     ptm = gmtime_r(&t, &tmbuf);
  432.     if (ptm) {
  433.         if (!strftime(buf, size, "%Y-%m-%dT%H:%M:%S", ptm))
  434.             buf[0] = '\0';
  435.     }
  436. }
  437.  
  438. static int write_manifest(AVFormatContext *s, int final)
  439. {
  440.     DASHContext *c = s->priv_data;
  441.     AVIOContext *out;
  442.     char temp_filename[1024];
  443.     int ret, i;
  444.     AVDictionaryEntry *title = av_dict_get(s->metadata, "title", NULL, 0);
  445.  
  446.     snprintf(temp_filename, sizeof(temp_filename), "%s.tmp", s->filename);
  447.     ret = avio_open2(&out, temp_filename, AVIO_FLAG_WRITE, &s->interrupt_callback, NULL);
  448.     if (ret < 0) {
  449.         av_log(s, AV_LOG_ERROR, "Unable to open %s for writing\n", temp_filename);
  450.         return ret;
  451.     }
  452.     avio_printf(out, "<?xml version=\"1.0\" encoding=\"utf-8\"?>\n");
  453.     avio_printf(out, "<MPD xmlns:xsi=\"http://www.w3.org/2001/XMLSchema-instance\"\n"
  454.                 "\txmlns=\"urn:mpeg:dash:schema:mpd:2011\"\n"
  455.                 "\txmlns:xlink=\"http://www.w3.org/1999/xlink\"\n"
  456.                 "\txsi:schemaLocation=\"urn:mpeg:DASH:schema:MPD:2011 http://standards.iso.org/ittf/PubliclyAvailableStandards/MPEG-DASH_schema_files/DASH-MPD.xsd\"\n"
  457.                 "\tprofiles=\"urn:mpeg:dash:profile:isoff-live:2011\"\n"
  458.                 "\ttype=\"%s\"\n", final ? "static" : "dynamic");
  459.     if (final) {
  460.         avio_printf(out, "\tmediaPresentationDuration=\"");
  461.         write_time(out, c->total_duration);
  462.         avio_printf(out, "\"\n");
  463.     } else {
  464.         int64_t update_period = c->last_duration / AV_TIME_BASE;
  465.         char now_str[100];
  466.         if (c->use_template && !c->use_timeline)
  467.             update_period = 500;
  468.         avio_printf(out, "\tminimumUpdatePeriod=\"PT%"PRId64"S\"\n", update_period);
  469.         avio_printf(out, "\tsuggestedPresentationDelay=\"PT%"PRId64"S\"\n", c->last_duration / AV_TIME_BASE);
  470.         if (!c->availability_start_time[0] && s->nb_streams > 0 && c->streams[0].nb_segments > 0) {
  471.             format_date_now(c->availability_start_time, sizeof(c->availability_start_time));
  472.         }
  473.         if (c->availability_start_time[0])
  474.             avio_printf(out, "\tavailabilityStartTime=\"%s\"\n", c->availability_start_time);
  475.         format_date_now(now_str, sizeof(now_str));
  476.         if (now_str[0])
  477.             avio_printf(out, "\tpublishTime=\"%s\"\n", now_str);
  478.         if (c->window_size && c->use_template) {
  479.             avio_printf(out, "\ttimeShiftBufferDepth=\"");
  480.             write_time(out, c->last_duration * c->window_size);
  481.             avio_printf(out, "\"\n");
  482.         }
  483.     }
  484.     avio_printf(out, "\tminBufferTime=\"");
  485.     write_time(out, c->last_duration);
  486.     avio_printf(out, "\">\n");
  487.     avio_printf(out, "\t<ProgramInformation>\n");
  488.     if (title) {
  489.         char *escaped = xmlescape(title->value);
  490.         avio_printf(out, "\t\t<Title>%s</Title>\n", escaped);
  491.         av_free(escaped);
  492.     }
  493.     avio_printf(out, "\t</ProgramInformation>\n");
  494.     if (c->window_size && s->nb_streams > 0 && c->streams[0].nb_segments > 0 && !c->use_template) {
  495.         OutputStream *os = &c->streams[0];
  496.         int start_index = FFMAX(os->nb_segments - c->window_size, 0);
  497.         int64_t start_time = av_rescale_q(os->segments[start_index]->time, s->streams[0]->time_base, AV_TIME_BASE_Q);
  498.         avio_printf(out, "\t<Period start=\"");
  499.         write_time(out, start_time);
  500.         avio_printf(out, "\">\n");
  501.     } else {
  502.         avio_printf(out, "\t<Period start=\"PT0.0S\">\n");
  503.     }
  504.  
  505.     if (c->has_video) {
  506.         avio_printf(out, "\t\t<AdaptationSet contentType=\"video\" segmentAlignment=\"true\" bitstreamSwitching=\"true\">\n");
  507.         for (i = 0; i < s->nb_streams; i++) {
  508.             AVStream *st = s->streams[i];
  509.             OutputStream *os = &c->streams[i];
  510.  
  511.             if (st->codec->codec_type != AVMEDIA_TYPE_VIDEO)
  512.                 continue;
  513.  
  514.             avio_printf(out, "\t\t\t<Representation id=\"%d\" mimeType=\"video/mp4\" codecs=\"%s\"%s width=\"%d\" height=\"%d\">\n", i, os->codec_str, os->bandwidth_str, st->codec->width, st->codec->height);
  515.             output_segment_list(&c->streams[i], out, c);
  516.             avio_printf(out, "\t\t\t</Representation>\n");
  517.         }
  518.         avio_printf(out, "\t\t</AdaptationSet>\n");
  519.     }
  520.     if (c->has_audio) {
  521.         avio_printf(out, "\t\t<AdaptationSet contentType=\"audio\" segmentAlignment=\"true\" bitstreamSwitching=\"true\">\n");
  522.         for (i = 0; i < s->nb_streams; i++) {
  523.             AVStream *st = s->streams[i];
  524.             OutputStream *os = &c->streams[i];
  525.  
  526.             if (st->codec->codec_type != AVMEDIA_TYPE_AUDIO)
  527.                 continue;
  528.  
  529.             avio_printf(out, "\t\t\t<Representation id=\"%d\" mimeType=\"audio/mp4\" codecs=\"%s\"%s audioSamplingRate=\"%d\">\n", i, os->codec_str, os->bandwidth_str, st->codec->sample_rate);
  530.             avio_printf(out, "\t\t\t\t<AudioChannelConfiguration schemeIdUri=\"urn:mpeg:dash:23003:3:audio_channel_configuration:2011\" value=\"%d\" />\n", st->codec->channels);
  531.             output_segment_list(&c->streams[i], out, c);
  532.             avio_printf(out, "\t\t\t</Representation>\n");
  533.         }
  534.         avio_printf(out, "\t\t</AdaptationSet>\n");
  535.     }
  536.     avio_printf(out, "\t</Period>\n");
  537.     avio_printf(out, "</MPD>\n");
  538.     avio_flush(out);
  539.     avio_close(out);
  540.     return ff_rename(temp_filename, s->filename, s);
  541. }
  542.  
  543. static int dash_write_header(AVFormatContext *s)
  544. {
  545.     DASHContext *c = s->priv_data;
  546.     int ret = 0, i;
  547.     AVOutputFormat *oformat;
  548.     char *ptr;
  549.     char basename[1024];
  550.  
  551.     if (c->single_file_name)
  552.         c->single_file = 1;
  553.     if (c->single_file)
  554.         c->use_template = 0;
  555.  
  556.     av_strlcpy(c->dirname, s->filename, sizeof(c->dirname));
  557.     ptr = strrchr(c->dirname, '/');
  558.     if (ptr) {
  559.         av_strlcpy(basename, &ptr[1], sizeof(basename));
  560.         ptr[1] = '\0';
  561.     } else {
  562.         c->dirname[0] = '\0';
  563.         av_strlcpy(basename, s->filename, sizeof(basename));
  564.     }
  565.  
  566.     ptr = strrchr(basename, '.');
  567.     if (ptr)
  568.         *ptr = '\0';
  569.  
  570.     oformat = av_guess_format("mp4", NULL, NULL);
  571.     if (!oformat) {
  572.         ret = AVERROR_MUXER_NOT_FOUND;
  573.         goto fail;
  574.     }
  575.  
  576.     c->streams = av_mallocz(sizeof(*c->streams) * s->nb_streams);
  577.     if (!c->streams) {
  578.         ret = AVERROR(ENOMEM);
  579.         goto fail;
  580.     }
  581.  
  582.     for (i = 0; i < s->nb_streams; i++) {
  583.         OutputStream *os = &c->streams[i];
  584.         AVFormatContext *ctx;
  585.         AVStream *st;
  586.         AVDictionary *opts = NULL;
  587.         char filename[1024];
  588.  
  589.         os->bit_rate = s->streams[i]->codec->bit_rate ?
  590.                        s->streams[i]->codec->bit_rate :
  591.                        s->streams[i]->codec->rc_max_rate;
  592.         if (os->bit_rate) {
  593.             snprintf(os->bandwidth_str, sizeof(os->bandwidth_str),
  594.                      " bandwidth=\"%d\"", os->bit_rate);
  595.         } else {
  596.             int level = s->strict_std_compliance >= FF_COMPLIANCE_STRICT ?
  597.                         AV_LOG_ERROR : AV_LOG_WARNING;
  598.             av_log(s, level, "No bit rate set for stream %d\n", i);
  599.             if (s->strict_std_compliance >= FF_COMPLIANCE_STRICT) {
  600.                 ret = AVERROR(EINVAL);
  601.                 goto fail;
  602.             }
  603.         }
  604.  
  605.         ctx = avformat_alloc_context();
  606.         if (!ctx) {
  607.             ret = AVERROR(ENOMEM);
  608.             goto fail;
  609.         }
  610.         os->ctx = ctx;
  611.         ctx->oformat = oformat;
  612.         ctx->interrupt_callback = s->interrupt_callback;
  613.  
  614.         if (!(st = avformat_new_stream(ctx, NULL))) {
  615.             ret = AVERROR(ENOMEM);
  616.             goto fail;
  617.         }
  618.         avcodec_copy_context(st->codec, s->streams[i]->codec);
  619.         st->sample_aspect_ratio = s->streams[i]->sample_aspect_ratio;
  620.         st->time_base = s->streams[i]->time_base;
  621.         ctx->avoid_negative_ts = s->avoid_negative_ts;
  622.  
  623.         ctx->pb = avio_alloc_context(os->iobuf, sizeof(os->iobuf), AVIO_FLAG_WRITE, os, NULL, dash_write, NULL);
  624.         if (!ctx->pb) {
  625.             ret = AVERROR(ENOMEM);
  626.             goto fail;
  627.         }
  628.  
  629.         if (c->single_file) {
  630.             if (c->single_file_name)
  631.                 dash_fill_tmpl_params(os->initfile, sizeof(os->initfile), c->single_file_name, i, 0, os->bit_rate, 0);
  632.             else
  633.                 snprintf(os->initfile, sizeof(os->initfile), "%s-stream%d.m4s", basename, i);
  634.         } else {
  635.             dash_fill_tmpl_params(os->initfile, sizeof(os->initfile), c->init_seg_name, i, 0, os->bit_rate, 0);
  636.         }
  637.         snprintf(filename, sizeof(filename), "%s%s", c->dirname, os->initfile);
  638.         ret = ffurl_open(&os->out, filename, AVIO_FLAG_WRITE, &s->interrupt_callback, NULL);
  639.         if (ret < 0)
  640.             goto fail;
  641.         os->init_start_pos = 0;
  642.  
  643.         av_dict_set(&opts, "movflags", "frag_custom+dash+delay_moov", 0);
  644.         if ((ret = avformat_write_header(ctx, &opts)) < 0) {
  645.              goto fail;
  646.         }
  647.         os->ctx_inited = 1;
  648.         avio_flush(ctx->pb);
  649.         av_dict_free(&opts);
  650.  
  651.         av_log(s, AV_LOG_VERBOSE, "Representation %d init segment will be written to: %s\n", i, filename);
  652.  
  653.         s->streams[i]->time_base = st->time_base;
  654.         // If the muxer wants to shift timestamps, request to have them shifted
  655.         // already before being handed to this muxer, so we don't have mismatches
  656.         // between the MPD and the actual segments.
  657.         s->avoid_negative_ts = ctx->avoid_negative_ts;
  658.         if (st->codec->codec_type == AVMEDIA_TYPE_VIDEO)
  659.             c->has_video = 1;
  660.         else if (st->codec->codec_type == AVMEDIA_TYPE_AUDIO)
  661.             c->has_audio = 1;
  662.  
  663.         set_codec_str(s, st->codec, os->codec_str, sizeof(os->codec_str));
  664.         os->first_pts = AV_NOPTS_VALUE;
  665.         os->max_pts = AV_NOPTS_VALUE;
  666.         os->last_dts = AV_NOPTS_VALUE;
  667.         os->segment_index = 1;
  668.     }
  669.  
  670.     if (!c->has_video && c->min_seg_duration <= 0) {
  671.         av_log(s, AV_LOG_WARNING, "no video stream and no min seg duration set\n");
  672.         ret = AVERROR(EINVAL);
  673.     }
  674.     ret = write_manifest(s, 0);
  675.     if (!ret)
  676.         av_log(s, AV_LOG_VERBOSE, "Manifest written to: %s\n", s->filename);
  677.  
  678. fail:
  679.     if (ret)
  680.         dash_free(s);
  681.     return ret;
  682. }
  683.  
  684. static int add_segment(OutputStream *os, const char *file,
  685.                        int64_t time, int duration,
  686.                        int64_t start_pos, int64_t range_length,
  687.                        int64_t index_length)
  688. {
  689.     int err;
  690.     Segment *seg;
  691.     if (os->nb_segments >= os->segments_size) {
  692.         os->segments_size = (os->segments_size + 1) * 2;
  693.         if ((err = av_reallocp(&os->segments, sizeof(*os->segments) *
  694.                                os->segments_size)) < 0) {
  695.             os->segments_size = 0;
  696.             os->nb_segments = 0;
  697.             return err;
  698.         }
  699.     }
  700.     seg = av_mallocz(sizeof(*seg));
  701.     if (!seg)
  702.         return AVERROR(ENOMEM);
  703.     av_strlcpy(seg->file, file, sizeof(seg->file));
  704.     seg->time = time;
  705.     seg->duration = duration;
  706.     if (seg->time < 0) { // If pts<0, it is expected to be cut away with an edit list
  707.         seg->duration += seg->time;
  708.         seg->time = 0;
  709.     }
  710.     seg->start_pos = start_pos;
  711.     seg->range_length = range_length;
  712.     seg->index_length = index_length;
  713.     os->segments[os->nb_segments++] = seg;
  714.     os->segment_index++;
  715.     return 0;
  716. }
  717.  
  718. static void write_styp(AVIOContext *pb)
  719. {
  720.     avio_wb32(pb, 24);
  721.     ffio_wfourcc(pb, "styp");
  722.     ffio_wfourcc(pb, "msdh");
  723.     avio_wb32(pb, 0); /* minor */
  724.     ffio_wfourcc(pb, "msdh");
  725.     ffio_wfourcc(pb, "msix");
  726. }
  727.  
  728. static void find_index_range(AVFormatContext *s, const char *full_path,
  729.                              int64_t pos, int *index_length)
  730. {
  731.     uint8_t buf[8];
  732.     URLContext *fd;
  733.     int ret;
  734.  
  735.     ret = ffurl_open(&fd, full_path, AVIO_FLAG_READ, &s->interrupt_callback, NULL);
  736.     if (ret < 0)
  737.         return;
  738.     if (ffurl_seek(fd, pos, SEEK_SET) != pos) {
  739.         ffurl_close(fd);
  740.         return;
  741.     }
  742.     ret = ffurl_read(fd, buf, 8);
  743.     ffurl_close(fd);
  744.     if (ret < 8)
  745.         return;
  746.     if (AV_RL32(&buf[4]) != MKTAG('s', 'i', 'd', 'x'))
  747.         return;
  748.     *index_length = AV_RB32(&buf[0]);
  749. }
  750.  
  751. static int update_stream_extradata(AVFormatContext *s, OutputStream *os,
  752.                                    AVCodecContext *codec)
  753. {
  754.     uint8_t *extradata;
  755.  
  756.     if (os->ctx->streams[0]->codec->extradata_size || !codec->extradata_size)
  757.         return 0;
  758.  
  759.     extradata = av_malloc(codec->extradata_size);
  760.  
  761.     if (!extradata)
  762.         return AVERROR(ENOMEM);
  763.  
  764.     memcpy(extradata, codec->extradata, codec->extradata_size);
  765.  
  766.     os->ctx->streams[0]->codec->extradata = extradata;
  767.     os->ctx->streams[0]->codec->extradata_size = codec->extradata_size;
  768.  
  769.     set_codec_str(s, codec, os->codec_str, sizeof(os->codec_str));
  770.  
  771.     return 0;
  772. }
  773.  
  774. static int dash_flush(AVFormatContext *s, int final, int stream)
  775. {
  776.     DASHContext *c = s->priv_data;
  777.     int i, ret = 0;
  778.     int cur_flush_segment_index = 0;
  779.     if (stream >= 0)
  780.         cur_flush_segment_index = c->streams[stream].segment_index;
  781.  
  782.     for (i = 0; i < s->nb_streams; i++) {
  783.         OutputStream *os = &c->streams[i];
  784.         char filename[1024] = "", full_path[1024], temp_path[1024];
  785.         int64_t start_pos;
  786.         int range_length, index_length = 0;
  787.  
  788.         if (!os->packets_written)
  789.             continue;
  790.  
  791.         // Flush the single stream that got a keyframe right now.
  792.         // Flush all audio streams as well, in sync with video keyframes,
  793.         // but not the other video streams.
  794.         if (stream >= 0 && i != stream) {
  795.             if (s->streams[i]->codec->codec_type != AVMEDIA_TYPE_AUDIO)
  796.                 continue;
  797.             // Make sure we don't flush audio streams multiple times, when
  798.             // all video streams are flushed one at a time.
  799.             if (c->has_video && os->segment_index > cur_flush_segment_index)
  800.                 continue;
  801.         }
  802.  
  803.         if (!os->init_range_length) {
  804.             av_write_frame(os->ctx, NULL);
  805.             os->init_range_length = avio_tell(os->ctx->pb);
  806.             if (!c->single_file) {
  807.                 ffurl_close(os->out);
  808.                 os->out = NULL;
  809.             }
  810.         }
  811.  
  812.         start_pos = avio_tell(os->ctx->pb);
  813.  
  814.         if (!c->single_file) {
  815.             dash_fill_tmpl_params(filename, sizeof(filename), c->media_seg_name, i, os->segment_index, os->bit_rate, os->start_pts);
  816.             snprintf(full_path, sizeof(full_path), "%s%s", c->dirname, filename);
  817.             snprintf(temp_path, sizeof(temp_path), "%s.tmp", full_path);
  818.             ret = ffurl_open(&os->out, temp_path, AVIO_FLAG_WRITE, &s->interrupt_callback, NULL);
  819.             if (ret < 0)
  820.                 break;
  821.             write_styp(os->ctx->pb);
  822.         } else {
  823.             snprintf(full_path, sizeof(full_path), "%s%s", c->dirname, os->initfile);
  824.         }
  825.  
  826.         av_write_frame(os->ctx, NULL);
  827.         avio_flush(os->ctx->pb);
  828.         os->packets_written = 0;
  829.  
  830.         range_length = avio_tell(os->ctx->pb) - start_pos;
  831.         if (c->single_file) {
  832.             find_index_range(s, full_path, start_pos, &index_length);
  833.         } else {
  834.             ffurl_close(os->out);
  835.             os->out = NULL;
  836.             ret = ff_rename(temp_path, full_path, s);
  837.             if (ret < 0)
  838.                 break;
  839.         }
  840.         add_segment(os, filename, os->start_pts, os->max_pts - os->start_pts, start_pos, range_length, index_length);
  841.         av_log(s, AV_LOG_VERBOSE, "Representation %d media segment %d written to: %s\n", i, os->segment_index, full_path);
  842.     }
  843.  
  844.     if (c->window_size || (final && c->remove_at_exit)) {
  845.         for (i = 0; i < s->nb_streams; i++) {
  846.             OutputStream *os = &c->streams[i];
  847.             int j;
  848.             int remove = os->nb_segments - c->window_size - c->extra_window_size;
  849.             if (final && c->remove_at_exit)
  850.                 remove = os->nb_segments;
  851.             if (remove > 0) {
  852.                 for (j = 0; j < remove; j++) {
  853.                     char filename[1024];
  854.                     snprintf(filename, sizeof(filename), "%s%s", c->dirname, os->segments[j]->file);
  855.                     unlink(filename);
  856.                     av_free(os->segments[j]);
  857.                 }
  858.                 os->nb_segments -= remove;
  859.                 memmove(os->segments, os->segments + remove, os->nb_segments * sizeof(*os->segments));
  860.             }
  861.         }
  862.     }
  863.  
  864.     if (ret >= 0)
  865.         ret = write_manifest(s, final);
  866.     return ret;
  867. }
  868.  
  869. static int dash_write_packet(AVFormatContext *s, AVPacket *pkt)
  870. {
  871.     DASHContext *c = s->priv_data;
  872.     AVStream *st = s->streams[pkt->stream_index];
  873.     OutputStream *os = &c->streams[pkt->stream_index];
  874.     int64_t seg_end_duration = (os->segment_index) * (int64_t) c->min_seg_duration;
  875.     int ret;
  876.  
  877.     ret = update_stream_extradata(s, os, st->codec);
  878.     if (ret < 0)
  879.         return ret;
  880.  
  881.     // Fill in a heuristic guess of the packet duration, if none is available.
  882.     // The mp4 muxer will do something similar (for the last packet in a fragment)
  883.     // if nothing is set (setting it for the other packets doesn't hurt).
  884.     // By setting a nonzero duration here, we can be sure that the mp4 muxer won't
  885.     // invoke its heuristic (this doesn't have to be identical to that algorithm),
  886.     // so that we know the exact timestamps of fragments.
  887.     if (!pkt->duration && os->last_dts != AV_NOPTS_VALUE)
  888.         pkt->duration = pkt->dts - os->last_dts;
  889.     os->last_dts = pkt->dts;
  890.  
  891.     // If forcing the stream to start at 0, the mp4 muxer will set the start
  892.     // timestamps to 0. Do the same here, to avoid mismatches in duration/timestamps.
  893.     if (os->first_pts == AV_NOPTS_VALUE &&
  894.         s->avoid_negative_ts == AVFMT_AVOID_NEG_TS_MAKE_ZERO) {
  895.         pkt->pts -= pkt->dts;
  896.         pkt->dts  = 0;
  897.     }
  898.  
  899.     if (os->first_pts == AV_NOPTS_VALUE)
  900.         os->first_pts = pkt->pts;
  901.  
  902.     if ((!c->has_video || st->codec->codec_type == AVMEDIA_TYPE_VIDEO) &&
  903.         pkt->flags & AV_PKT_FLAG_KEY && os->packets_written &&
  904.         av_compare_ts(pkt->pts - os->first_pts, st->time_base,
  905.                       seg_end_duration, AV_TIME_BASE_Q) >= 0) {
  906.         int64_t prev_duration = c->last_duration;
  907.  
  908.         c->last_duration = av_rescale_q(pkt->pts - os->start_pts,
  909.                                         st->time_base,
  910.                                         AV_TIME_BASE_Q);
  911.         c->total_duration = av_rescale_q(pkt->pts - os->first_pts,
  912.                                          st->time_base,
  913.                                          AV_TIME_BASE_Q);
  914.  
  915.         if ((!c->use_timeline || !c->use_template) && prev_duration) {
  916.             if (c->last_duration < prev_duration*9/10 ||
  917.                 c->last_duration > prev_duration*11/10) {
  918.                 av_log(s, AV_LOG_WARNING,
  919.                        "Segment durations differ too much, enable use_timeline "
  920.                        "and use_template, or keep a stricter keyframe interval\n");
  921.             }
  922.         }
  923.  
  924.         if ((ret = dash_flush(s, 0, pkt->stream_index)) < 0)
  925.             return ret;
  926.     }
  927.  
  928.     if (!os->packets_written) {
  929.         // If we wrote a previous segment, adjust the start time of the segment
  930.         // to the end of the previous one (which is the same as the mp4 muxer
  931.         // does). This avoids gaps in the timeline.
  932.         if (os->max_pts != AV_NOPTS_VALUE)
  933.             os->start_pts = os->max_pts;
  934.         else
  935.             os->start_pts = pkt->pts;
  936.     }
  937.     if (os->max_pts == AV_NOPTS_VALUE)
  938.         os->max_pts = pkt->pts + pkt->duration;
  939.     else
  940.         os->max_pts = FFMAX(os->max_pts, pkt->pts + pkt->duration);
  941.     os->packets_written++;
  942.     return ff_write_chained(os->ctx, 0, pkt, s, 0);
  943. }
  944.  
  945. static int dash_write_trailer(AVFormatContext *s)
  946. {
  947.     DASHContext *c = s->priv_data;
  948.  
  949.     if (s->nb_streams > 0) {
  950.         OutputStream *os = &c->streams[0];
  951.         // If no segments have been written so far, try to do a crude
  952.         // guess of the segment duration
  953.         if (!c->last_duration)
  954.             c->last_duration = av_rescale_q(os->max_pts - os->start_pts,
  955.                                             s->streams[0]->time_base,
  956.                                             AV_TIME_BASE_Q);
  957.         c->total_duration = av_rescale_q(os->max_pts - os->first_pts,
  958.                                          s->streams[0]->time_base,
  959.                                          AV_TIME_BASE_Q);
  960.     }
  961.     dash_flush(s, 1, -1);
  962.  
  963.     if (c->remove_at_exit) {
  964.         char filename[1024];
  965.         int i;
  966.         for (i = 0; i < s->nb_streams; i++) {
  967.             OutputStream *os = &c->streams[i];
  968.             snprintf(filename, sizeof(filename), "%s%s", c->dirname, os->initfile);
  969.             unlink(filename);
  970.         }
  971.         unlink(s->filename);
  972.     }
  973.  
  974.     dash_free(s);
  975.     return 0;
  976. }
  977.  
  978. #define OFFSET(x) offsetof(DASHContext, x)
  979. #define E AV_OPT_FLAG_ENCODING_PARAM
  980. static const AVOption options[] = {
  981.     { "window_size", "number of segments kept in the manifest", OFFSET(window_size), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, INT_MAX, E },
  982.     { "extra_window_size", "number of segments kept outside of the manifest before removing from disk", OFFSET(extra_window_size), AV_OPT_TYPE_INT, { .i64 = 5 }, 0, INT_MAX, E },
  983.     { "min_seg_duration", "minimum segment duration (in microseconds)", OFFSET(min_seg_duration), AV_OPT_TYPE_INT64, { .i64 = 5000000 }, 0, INT_MAX, E },
  984.     { "remove_at_exit", "remove all segments when finished", OFFSET(remove_at_exit), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, 1, E },
  985.     { "use_template", "Use SegmentTemplate instead of SegmentList", OFFSET(use_template), AV_OPT_TYPE_INT, { .i64 = 1 }, 0, 1, E },
  986.     { "use_timeline", "Use SegmentTimeline in SegmentTemplate", OFFSET(use_timeline), AV_OPT_TYPE_INT, { .i64 = 1 }, 0, 1, E },
  987.     { "single_file", "Store all segments in one file, accessed using byte ranges", OFFSET(single_file), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, 1, E },
  988.     { "single_file_name", "DASH-templated name to be used for baseURL. Implies storing all segments in one file, accessed using byte ranges", OFFSET(single_file_name), AV_OPT_TYPE_STRING, { .str = NULL }, 0, 0, E },
  989.     { "init_seg_name", "DASH-templated name to used for the initialization segment", OFFSET(init_seg_name), AV_OPT_TYPE_STRING, {.str = "init-stream$RepresentationID$.m4s"}, 0, 0, E },
  990.     { "media_seg_name", "DASH-templated name to used for the media segments", OFFSET(media_seg_name), AV_OPT_TYPE_STRING, {.str = "chunk-stream$RepresentationID$-$Number%05d$.m4s"}, 0, 0, E },
  991.     { NULL },
  992. };
  993.  
  994. static const AVClass dash_class = {
  995.     .class_name = "dash muxer",
  996.     .item_name  = av_default_item_name,
  997.     .option     = options,
  998.     .version    = LIBAVUTIL_VERSION_INT,
  999. };
  1000.  
  1001. AVOutputFormat ff_dash_muxer = {
  1002.     .name           = "dash",
  1003.     .long_name      = NULL_IF_CONFIG_SMALL("DASH Muxer"),
  1004.     .priv_data_size = sizeof(DASHContext),
  1005.     .audio_codec    = AV_CODEC_ID_AAC,
  1006.     .video_codec    = AV_CODEC_ID_H264,
  1007.     .flags          = AVFMT_GLOBALHEADER | AVFMT_NOFILE | AVFMT_TS_NEGATIVE,
  1008.     .write_header   = dash_write_header,
  1009.     .write_packet   = dash_write_packet,
  1010.     .write_trailer  = dash_write_trailer,
  1011.     .codec_tag      = (const AVCodecTag* const []){ ff_mp4_obj_type, 0 },
  1012.     .priv_class     = &dash_class,
  1013. };
  1014.