/* * MPEG-DASH ISO BMFF segmenter * Copyright (c) 2014 Martin Storsjo * * This file is part of Libav. * * Libav is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2.1 of the License, or (at your option) any later version. * * Libav is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with Libav; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ #include "config.h" #if HAVE_UNISTD_H #include #endif #include "libavutil/avutil.h" #include "libavutil/avstring.h" #include "libavutil/intreadwrite.h" #include "libavutil/mathematics.h" #include "libavutil/opt.h" #include "libavutil/time_internal.h" #include "avc.h" #include "avformat.h" #include "avio_internal.h" #include "internal.h" #include "isom.h" #include "os_support.h" #include "url.h" // See ISO/IEC 23009-1:2014 5.3.9.4.4 typedef enum { DASH_TMPL_ID_UNDEFINED = -1, DASH_TMPL_ID_ESCAPE, DASH_TMPL_ID_REP_ID, DASH_TMPL_ID_NUMBER, DASH_TMPL_ID_BANDWIDTH, DASH_TMPL_ID_TIME, } DASHTmplId; typedef struct Segment { char file[1024]; int64_t start_pos; int range_length, index_length; int64_t time; int duration; int n; } Segment; typedef struct AdaptationSet { char id[10]; enum AVMediaType media_type; AVDictionary *metadata; } AdaptationSet; typedef struct OutputStream { AVFormatContext *ctx; int ctx_inited, as_idx; AVIOContext *out; char format_name[8]; int packets_written; char initfile[1024]; int64_t init_start_pos, pos; int init_range_length; int nb_segments, segments_size, segment_index; Segment **segments; int64_t first_pts, start_pts, max_pts; int64_t last_dts; int bit_rate; char bandwidth_str[64]; char codec_str[100]; } OutputStream; typedef struct DASHContext { const AVClass *class; /* Class for private options. */ char *adaptation_sets; AdaptationSet *as; int nb_as; int window_size; int extra_window_size; int min_seg_duration; int remove_at_exit; int use_template; int use_timeline; int single_file; OutputStream *streams; int has_video; int64_t last_duration; int64_t total_duration; char availability_start_time[100]; char dirname[1024]; const char *single_file_name; const char *init_seg_name; const char *media_seg_name; const char *utc_timing_url; } DASHContext; static struct codec_string { int id; const char *str; } codecs[] = { { AV_CODEC_ID_VP8, "vp8" }, { AV_CODEC_ID_VP9, "vp9" }, { AV_CODEC_ID_VORBIS, "vorbis" }, { AV_CODEC_ID_OPUS, "opus" }, { 0, NULL } }; static void set_codec_str(AVFormatContext *s, AVCodecParameters *par, char *str, int size) { const AVCodecTag *tags[2] = { NULL, NULL }; uint32_t tag; int i; // common Webm codecs are not part of RFC 6381 for (i = 0; codecs[i].id; i++) if (codecs[i].id == par->codec_id) { av_strlcpy(str, codecs[i].str, size); return; } // for codecs part of RFC 6381 if (par->codec_type == AVMEDIA_TYPE_VIDEO) tags[0] = ff_codec_movvideo_tags; else if (par->codec_type == AVMEDIA_TYPE_AUDIO) tags[0] = ff_codec_movaudio_tags; else return; tag = av_codec_get_tag(tags, par->codec_id); if (!tag) return; if (size < 5) return; AV_WL32(str, tag); str[4] = '\0'; if (!strcmp(str, "mp4a") || !strcmp(str, "mp4v")) { uint32_t oti; tags[0] = ff_mp4_obj_type; oti = av_codec_get_tag(tags, par->codec_id); if (oti) av_strlcatf(str, size, ".%02"SCNx32, oti); else return; if (tag == MKTAG('m', 'p', '4', 'a')) { if (par->extradata_size >= 2) { int aot = par->extradata[0] >> 3; if (aot == 31) aot = ((AV_RB16(par->extradata) >> 5) & 0x3f) + 32; av_strlcatf(str, size, ".%d", aot); } } else if (tag == MKTAG('m', 'p', '4', 'v')) { // Unimplemented, should output ProfileLevelIndication as a decimal number av_log(s, AV_LOG_WARNING, "Incomplete RFC 6381 codec string for mp4v\n"); } } else if (!strcmp(str, "avc1")) { uint8_t *tmpbuf = NULL; uint8_t *extradata = par->extradata; int extradata_size = par->extradata_size; if (!extradata_size) return; if (extradata[0] != 1) { AVIOContext *pb; if (avio_open_dyn_buf(&pb) < 0) return; if (ff_isom_write_avcc(pb, extradata, extradata_size) < 0) { ffio_free_dyn_buf(&pb); return; } extradata_size = avio_close_dyn_buf(pb, &extradata); tmpbuf = extradata; } if (extradata_size >= 4) av_strlcatf(str, size, ".%02x%02x%02x", extradata[1], extradata[2], extradata[3]); av_free(tmpbuf); } } static int flush_dynbuf(OutputStream *os, int *range_length) { uint8_t *buffer; if (!os->ctx->pb) { return AVERROR(EINVAL); } // flush av_write_frame(os->ctx, NULL); avio_flush(os->ctx->pb); // write out to file *range_length = avio_close_dyn_buf(os->ctx->pb, &buffer); os->ctx->pb = NULL; avio_write(os->out, buffer, *range_length); av_free(buffer); // re-open buffer return avio_open_dyn_buf(&os->ctx->pb); } static int flush_init_segment(AVFormatContext *s, OutputStream *os) { DASHContext *c = s->priv_data; int ret, range_length; ret = flush_dynbuf(os, &range_length); if (ret < 0) return ret; os->pos = os->init_range_length = range_length; if (!c->single_file) ff_format_io_close(s, &os->out); return 0; } static void dash_free(AVFormatContext *s) { DASHContext *c = s->priv_data; int i, j; if (c->as) { for (i = 0; i < c->nb_as; i++) av_dict_free(&c->as[i].metadata); av_freep(&c->as); c->nb_as = 0; } if (!c->streams) return; for (i = 0; i < s->nb_streams; i++) { OutputStream *os = &c->streams[i]; if (os->ctx && os->ctx_inited) av_write_trailer(os->ctx); if (os->ctx && os->ctx->pb) ffio_free_dyn_buf(&os->ctx->pb); ff_format_io_close(s, &os->out); if (os->ctx) avformat_free_context(os->ctx); for (j = 0; j < os->nb_segments; j++) av_free(os->segments[j]); av_free(os->segments); } av_freep(&c->streams); } static void output_segment_list(OutputStream *os, AVIOContext *out, DASHContext *c) { int i, start_index = 0, start_number = 1; if (c->window_size) { start_index = FFMAX(os->nb_segments - c->window_size, 0); start_number = FFMAX(os->segment_index - c->window_size, 1); } if (c->use_template) { int timescale = c->use_timeline ? os->ctx->streams[0]->time_base.den : AV_TIME_BASE; avio_printf(out, "\t\t\t\tuse_timeline) avio_printf(out, "duration=\"%"PRId64"\" ", c->last_duration); avio_printf(out, "initialization=\"%s\" media=\"%s\" startNumber=\"%d\">\n", c->init_seg_name, c->media_seg_name, c->use_timeline ? start_number : 1); if (c->use_timeline) { int64_t cur_time = 0; avio_printf(out, "\t\t\t\t\t\n"); for (i = start_index; i < os->nb_segments; ) { Segment *seg = os->segments[i]; int repeat = 0; avio_printf(out, "\t\t\t\t\t\ttime != cur_time) { cur_time = seg->time; avio_printf(out, "t=\"%"PRId64"\" ", seg->time); } avio_printf(out, "d=\"%d\" ", seg->duration); while (i + repeat + 1 < os->nb_segments && os->segments[i + repeat + 1]->duration == seg->duration && os->segments[i + repeat + 1]->time == os->segments[i + repeat]->time + os->segments[i + repeat]->duration) repeat++; if (repeat > 0) avio_printf(out, "r=\"%d\" ", repeat); avio_printf(out, "/>\n"); i += 1 + repeat; cur_time += (1 + repeat) * seg->duration; } avio_printf(out, "\t\t\t\t\t\n"); } avio_printf(out, "\t\t\t\t\n"); } else if (c->single_file) { avio_printf(out, "\t\t\t\t%s\n", os->initfile); avio_printf(out, "\t\t\t\t\n", AV_TIME_BASE, c->last_duration, start_number); avio_printf(out, "\t\t\t\t\t\n", os->init_start_pos, os->init_start_pos + os->init_range_length - 1); for (i = start_index; i < os->nb_segments; i++) { Segment *seg = os->segments[i]; avio_printf(out, "\t\t\t\t\tstart_pos, seg->start_pos + seg->range_length - 1); if (seg->index_length) avio_printf(out, "indexRange=\"%"PRId64"-%"PRId64"\" ", seg->start_pos, seg->start_pos + seg->index_length - 1); avio_printf(out, "/>\n"); } avio_printf(out, "\t\t\t\t\n"); } else { avio_printf(out, "\t\t\t\t\n", AV_TIME_BASE, c->last_duration, start_number); avio_printf(out, "\t\t\t\t\t\n", os->initfile); for (i = start_index; i < os->nb_segments; i++) { Segment *seg = os->segments[i]; avio_printf(out, "\t\t\t\t\t\n", seg->file); } avio_printf(out, "\t\t\t\t\n"); } } static DASHTmplId dash_read_tmpl_id(const char *identifier, char *format_tag, size_t format_tag_size, const char **ptr) { const char *next_ptr; DASHTmplId id_type = DASH_TMPL_ID_UNDEFINED; if (av_strstart(identifier, "$$", &next_ptr)) { id_type = DASH_TMPL_ID_ESCAPE; *ptr = next_ptr; } else if (av_strstart(identifier, "$RepresentationID$", &next_ptr)) { id_type = DASH_TMPL_ID_REP_ID; // default to basic format, as $RepresentationID$ identifiers // are not allowed to have custom format-tags. av_strlcpy(format_tag, "%d", format_tag_size); *ptr = next_ptr; } else { // the following identifiers may have an explicit format_tag if (av_strstart(identifier, "$Number", &next_ptr)) id_type = DASH_TMPL_ID_NUMBER; else if (av_strstart(identifier, "$Bandwidth", &next_ptr)) id_type = DASH_TMPL_ID_BANDWIDTH; else if (av_strstart(identifier, "$Time", &next_ptr)) id_type = DASH_TMPL_ID_TIME; else id_type = DASH_TMPL_ID_UNDEFINED; // next parse the dash format-tag and generate a c-string format tag // (next_ptr now points at the first '%' at the beginning of the format-tag) if (id_type != DASH_TMPL_ID_UNDEFINED) { const char *number_format = (id_type == DASH_TMPL_ID_TIME) ? PRId64 : "d"; if (next_ptr[0] == '$') { // no dash format-tag snprintf(format_tag, format_tag_size, "%%%s", number_format); *ptr = &next_ptr[1]; } else { const char *width_ptr; // only tolerate single-digit width-field (i.e. up to 9-digit width) if (av_strstart(next_ptr, "%0", &width_ptr) && av_isdigit(width_ptr[0]) && av_strstart(&width_ptr[1], "d$", &next_ptr)) { // yes, we're using a format tag to build format_tag. snprintf(format_tag, format_tag_size, "%s%c%s", "%0", width_ptr[0], number_format); *ptr = next_ptr; } else { av_log(NULL, AV_LOG_WARNING, "Failed to parse format-tag beginning with %s. Expected either a " "closing '$' character or a format-string like '%%0[width]d', " "where width must be a single digit\n", next_ptr); id_type = DASH_TMPL_ID_UNDEFINED; } } } } return id_type; } static void dash_fill_tmpl_params(char *dst, size_t buffer_size, const char *template, int rep_id, int number, int bit_rate, int64_t time) { int dst_pos = 0; const char *t_cur = template; while (dst_pos < buffer_size - 1 && *t_cur) { char format_tag[7]; // May be "%d", "%0Xd", or "%0Xlld" (for $Time$), where X is in [0-9] int n = 0; DASHTmplId id_type; const char *t_next = strchr(t_cur, '$'); // copy over everything up to the first '$' character if (t_next) { int num_copy_bytes = FFMIN(t_next - t_cur, buffer_size - dst_pos - 1); av_strlcpy(&dst[dst_pos], t_cur, num_copy_bytes + 1); // advance dst_pos += num_copy_bytes; t_cur = t_next; } else { // no more DASH identifiers to substitute - just copy the rest over and break av_strlcpy(&dst[dst_pos], t_cur, buffer_size - dst_pos); break; } if (dst_pos >= buffer_size - 1 || !*t_cur) break; // t_cur is now pointing to a '$' character id_type = dash_read_tmpl_id(t_cur, format_tag, sizeof(format_tag), &t_next); switch (id_type) { case DASH_TMPL_ID_ESCAPE: av_strlcpy(&dst[dst_pos], "$", 2); n = 1; break; case DASH_TMPL_ID_REP_ID: n = snprintf(&dst[dst_pos], buffer_size - dst_pos, format_tag, rep_id); break; case DASH_TMPL_ID_NUMBER: n = snprintf(&dst[dst_pos], buffer_size - dst_pos, format_tag, number); break; case DASH_TMPL_ID_BANDWIDTH: n = snprintf(&dst[dst_pos], buffer_size - dst_pos, format_tag, bit_rate); break; case DASH_TMPL_ID_TIME: n = snprintf(&dst[dst_pos], buffer_size - dst_pos, format_tag, time); break; case DASH_TMPL_ID_UNDEFINED: // copy over one byte and advance av_strlcpy(&dst[dst_pos], t_cur, 2); n = 1; t_next = &t_cur[1]; break; } // t_next points just past the processed identifier // n is the number of bytes that were attempted to be written to dst // (may have failed to write all because buffer_size). // advance dst_pos += FFMIN(n, buffer_size - dst_pos - 1); t_cur = t_next; } } static char *xmlescape(const char *str) { int outlen = strlen(str)*3/2 + 6; char *out = av_realloc(NULL, outlen + 1); int pos = 0; if (!out) return NULL; for (; *str; str++) { if (pos + 6 > outlen) { char *tmp; outlen = 2 * outlen + 6; tmp = av_realloc(out, outlen + 1); if (!tmp) { av_free(out); return NULL; } out = tmp; } if (*str == '&') { memcpy(&out[pos], "&", 5); pos += 5; } else if (*str == '<') { memcpy(&out[pos], "<", 4); pos += 4; } else if (*str == '>') { memcpy(&out[pos], ">", 4); pos += 4; } else if (*str == '\'') { memcpy(&out[pos], "'", 6); pos += 6; } else if (*str == '\"') { memcpy(&out[pos], """, 6); pos += 6; } else { out[pos++] = *str; } } out[pos] = '\0'; return out; } static void write_time(AVIOContext *out, int64_t time) { int seconds = time / AV_TIME_BASE; int fractions = time % AV_TIME_BASE; int minutes = seconds / 60; int hours = minutes / 60; seconds %= 60; minutes %= 60; avio_printf(out, "PT"); if (hours) avio_printf(out, "%dH", hours); if (hours || minutes) avio_printf(out, "%dM", minutes); avio_printf(out, "%d.%dS", seconds, fractions / (AV_TIME_BASE / 10)); } static void format_date_now(char *buf, int size) { time_t t = time(NULL); struct tm *ptm, tmbuf; ptm = gmtime_r(&t, &tmbuf); if (ptm) { if (!strftime(buf, size, "%Y-%m-%dT%H:%M:%SZ", ptm)) buf[0] = '\0'; } } static int write_adaptation_set(AVFormatContext *s, AVIOContext *out, int as_index) { DASHContext *c = s->priv_data; AdaptationSet *as = &c->as[as_index]; AVDictionaryEntry *lang, *role; int i; avio_printf(out, "\t\tid, as->media_type == AVMEDIA_TYPE_VIDEO ? "video" : "audio"); lang = av_dict_get(as->metadata, "language", NULL, 0); if (lang) avio_printf(out, " lang=\"%s\"", lang->value); avio_printf(out, ">\n"); role = av_dict_get(as->metadata, "role", NULL, 0); if (role) avio_printf(out, "\t\t\t\n", role->value); for (i = 0; i < s->nb_streams; i++) { OutputStream *os = &c->streams[i]; if (os->as_idx - 1 != as_index) continue; if (as->media_type == AVMEDIA_TYPE_VIDEO) { avio_printf(out, "\t\t\t\n", i, os->format_name, os->codec_str, os->bandwidth_str, s->streams[i]->codecpar->width, s->streams[i]->codecpar->height); } else { avio_printf(out, "\t\t\t\n", i, os->format_name, os->codec_str, os->bandwidth_str, s->streams[i]->codecpar->sample_rate); avio_printf(out, "\t\t\t\t\n", s->streams[i]->codecpar->channels); } output_segment_list(os, out, c); avio_printf(out, "\t\t\t\n"); } avio_printf(out, "\t\t\n"); return 0; } static int add_adaptation_set(AVFormatContext *s, AdaptationSet **as, enum AVMediaType type) { DASHContext *c = s->priv_data; void *mem = av_realloc(c->as, sizeof(*c->as) * (c->nb_as + 1)); if (!mem) return AVERROR(ENOMEM); c->as = mem; ++c->nb_as; *as = &c->as[c->nb_as - 1]; memset(*as, 0, sizeof(**as)); (*as)->media_type = type; return 0; } static int adaptation_set_add_stream(AVFormatContext *s, int as_idx, int i) { DASHContext *c = s->priv_data; AdaptationSet *as = &c->as[as_idx - 1]; OutputStream *os = &c->streams[i]; if (as->media_type != s->streams[i]->codecpar->codec_type) { av_log(s, AV_LOG_ERROR, "Codec type of stream %d doesn't match AdaptationSet's media type\n", i); return AVERROR(EINVAL); } else if (os->as_idx) { av_log(s, AV_LOG_ERROR, "Stream %d is already assigned to an AdaptationSet\n", i); return AVERROR(EINVAL); } os->as_idx = as_idx; return 0; } static int parse_adaptation_sets(AVFormatContext *s) { DASHContext *c = s->priv_data; const char *p = c->adaptation_sets; enum { new_set, parse_id, parsing_streams } state; AdaptationSet *as; int i, n, ret; // default: one AdaptationSet for each stream if (!p) { for (i = 0; i < s->nb_streams; i++) { if ((ret = add_adaptation_set(s, &as, s->streams[i]->codecpar->codec_type)) < 0) return ret; snprintf(as->id, sizeof(as->id), "%d", i); c->streams[i].as_idx = c->nb_as; } goto end; } // syntax id=0,streams=0,1,2 id=1,streams=3,4 and so on state = new_set; while (*p) { if (*p == ' ') { p++; continue; } else if (state == new_set && av_strstart(p, "id=", &p)) { if ((ret = add_adaptation_set(s, &as, AVMEDIA_TYPE_UNKNOWN)) < 0) return ret; n = strcspn(p, ","); snprintf(as->id, sizeof(as->id), "%.*s", n, p); p += n; if (*p) p++; state = parse_id; } else if (state == parse_id && av_strstart(p, "streams=", &p)) { state = parsing_streams; } else if (state == parsing_streams) { AdaptationSet *as = &c->as[c->nb_as - 1]; char idx_str[8], *end_str; n = strcspn(p, " ,"); snprintf(idx_str, sizeof(idx_str), "%.*s", n, p); p += n; // if value is "a" or "v", map all streams of that type if (as->media_type == AVMEDIA_TYPE_UNKNOWN && (idx_str[0] == 'v' || idx_str[0] == 'a')) { enum AVMediaType type = (idx_str[0] == 'v') ? AVMEDIA_TYPE_VIDEO : AVMEDIA_TYPE_AUDIO; av_log(s, AV_LOG_DEBUG, "Map all streams of type %s\n", idx_str); for (i = 0; i < s->nb_streams; i++) { if (s->streams[i]->codecpar->codec_type != type) continue; as->media_type = s->streams[i]->codecpar->codec_type; if ((ret = adaptation_set_add_stream(s, c->nb_as, i)) < 0) return ret; } } else { // select single stream i = strtol(idx_str, &end_str, 10); if (idx_str == end_str || i < 0 || i >= s->nb_streams) { av_log(s, AV_LOG_ERROR, "Selected stream \"%s\" not found!\n", idx_str); return AVERROR(EINVAL); } av_log(s, AV_LOG_DEBUG, "Map stream %d\n", i); if (as->media_type == AVMEDIA_TYPE_UNKNOWN) { as->media_type = s->streams[i]->codecpar->codec_type; } if ((ret = adaptation_set_add_stream(s, c->nb_as, i)) < 0) return ret; } if (*p == ' ') state = new_set; if (*p) p++; } else { return AVERROR(EINVAL); } } end: // check for unassigned streams for (i = 0; i < s->nb_streams; i++) { OutputStream *os = &c->streams[i]; if (!os->as_idx) { av_log(s, AV_LOG_ERROR, "Stream %d is not mapped to an AdaptationSet\n", i); return AVERROR(EINVAL); } } return 0; } static int write_manifest(AVFormatContext *s, int final) { DASHContext *c = s->priv_data; AVIOContext *out; char temp_filename[1024]; int ret, i; AVDictionaryEntry *title = av_dict_get(s->metadata, "title", NULL, 0); snprintf(temp_filename, sizeof(temp_filename), "%s.tmp", s->filename); ret = s->io_open(s, &out, temp_filename, AVIO_FLAG_WRITE, NULL); if (ret < 0) { av_log(s, AV_LOG_ERROR, "Unable to open %s for writing\n", temp_filename); return ret; } avio_printf(out, "\n"); avio_printf(out, "total_duration); avio_printf(out, "\"\n"); } else { int64_t update_period = c->last_duration / AV_TIME_BASE; char now_str[100]; if (c->use_template && !c->use_timeline) update_period = 500; avio_printf(out, "\tminimumUpdatePeriod=\"PT%"PRId64"S\"\n", update_period); avio_printf(out, "\tsuggestedPresentationDelay=\"PT%"PRId64"S\"\n", c->last_duration / AV_TIME_BASE); if (!c->availability_start_time[0] && s->nb_streams > 0 && c->streams[0].nb_segments > 0) { format_date_now(c->availability_start_time, sizeof(c->availability_start_time)); } if (c->availability_start_time[0]) avio_printf(out, "\tavailabilityStartTime=\"%s\"\n", c->availability_start_time); format_date_now(now_str, sizeof(now_str)); if (now_str[0]) avio_printf(out, "\tpublishTime=\"%s\"\n", now_str); if (c->window_size && c->use_template) { avio_printf(out, "\ttimeShiftBufferDepth=\""); write_time(out, c->last_duration * c->window_size); avio_printf(out, "\"\n"); } } avio_printf(out, "\tminBufferTime=\""); write_time(out, c->last_duration * 2); avio_printf(out, "\">\n"); avio_printf(out, "\t\n"); if (title) { char *escaped = xmlescape(title->value); avio_printf(out, "\t\t%s\n", escaped); av_free(escaped); } avio_printf(out, "\t\n"); if (c->utc_timing_url) avio_printf(out, "\t\n", c->utc_timing_url); if (c->window_size && s->nb_streams > 0 && c->streams[0].nb_segments > 0 && !c->use_template) { OutputStream *os = &c->streams[0]; int start_index = FFMAX(os->nb_segments - c->window_size, 0); int64_t start_time = av_rescale_q(os->segments[start_index]->time, s->streams[0]->time_base, AV_TIME_BASE_Q); avio_printf(out, "\t\n"); } else { avio_printf(out, "\t\n"); } for (i = 0; i < c->nb_as; i++) { if ((ret = write_adaptation_set(s, out, i)) < 0) return ret; } avio_printf(out, "\t\n"); avio_printf(out, "\n"); avio_flush(out); ff_format_io_close(s, &out); return ff_rename(temp_filename, s->filename); } static int dict_copy_entry(AVDictionary **dst, const AVDictionary *src, const char *key) { AVDictionaryEntry *entry = av_dict_get(src, key, NULL, 0); if (entry) av_dict_set(dst, key, entry->value, AV_DICT_DONT_OVERWRITE); return 0; } static int dict_set_int(AVDictionary **pm, const char *key, int64_t value, int flags) { char valuestr[22]; snprintf(valuestr, sizeof(valuestr), "%"PRId64, value); flags &= ~AV_DICT_DONT_STRDUP_VAL; return av_dict_set(pm, key, valuestr, flags); } static int dash_write_header(AVFormatContext *s) { DASHContext *c = s->priv_data; int ret = 0, i; char *ptr; char basename[1024]; if (c->single_file_name) c->single_file = 1; if (c->single_file) c->use_template = 0; av_strlcpy(c->dirname, s->filename, sizeof(c->dirname)); ptr = strrchr(c->dirname, '/'); if (ptr) { av_strlcpy(basename, &ptr[1], sizeof(basename)); ptr[1] = '\0'; } else { c->dirname[0] = '\0'; av_strlcpy(basename, s->filename, sizeof(basename)); } ptr = strrchr(basename, '.'); if (ptr) *ptr = '\0'; c->streams = av_mallocz(sizeof(*c->streams) * s->nb_streams); if (!c->streams) { ret = AVERROR(ENOMEM); goto fail; } if ((ret = parse_adaptation_sets(s)) < 0) goto fail; for (i = 0; i < s->nb_streams; i++) { OutputStream *os = &c->streams[i]; AdaptationSet *as = &c->as[os->as_idx - 1]; AVFormatContext *ctx; AVStream *st; AVDictionary *opts = NULL; char filename[1024]; os->bit_rate = s->streams[i]->codecpar->bit_rate; if (os->bit_rate) { snprintf(os->bandwidth_str, sizeof(os->bandwidth_str), " bandwidth=\"%d\"", os->bit_rate); } else { int level = s->strict_std_compliance >= FF_COMPLIANCE_STRICT ? AV_LOG_ERROR : AV_LOG_WARNING; av_log(s, level, "No bit rate set for stream %d\n", i); if (s->strict_std_compliance >= FF_COMPLIANCE_STRICT) { ret = AVERROR(EINVAL); goto fail; } } // copy AdaptationSet language and role from stream metadata dict_copy_entry(&as->metadata, s->streams[i]->metadata, "language"); dict_copy_entry(&as->metadata, s->streams[i]->metadata, "role"); ctx = avformat_alloc_context(); if (!ctx) { ret = AVERROR(ENOMEM); goto fail; } // choose muxer based on codec: webm for VP8/9 and opus, mp4 otherwise // note: os->format_name is also used as part of the mimetype of the // representation, e.g. video/ if (s->streams[i]->codecpar->codec_id == AV_CODEC_ID_VP8 || s->streams[i]->codecpar->codec_id == AV_CODEC_ID_VP9 || s->streams[i]->codecpar->codec_id == AV_CODEC_ID_OPUS || s->streams[i]->codecpar->codec_id == AV_CODEC_ID_VORBIS) { snprintf(os->format_name, sizeof(os->format_name), "webm"); } else { snprintf(os->format_name, sizeof(os->format_name), "mp4"); } ctx->oformat = av_guess_format(os->format_name, NULL, NULL); if (!ctx->oformat) { ret = AVERROR_MUXER_NOT_FOUND; goto fail; } os->ctx = ctx; ctx->interrupt_callback = s->interrupt_callback; ctx->opaque = s->opaque; ctx->io_close = s->io_close; ctx->io_open = s->io_open; if (!(st = avformat_new_stream(ctx, NULL))) { ret = AVERROR(ENOMEM); goto fail; } avcodec_parameters_copy(st->codecpar, s->streams[i]->codecpar); st->sample_aspect_ratio = s->streams[i]->sample_aspect_ratio; st->time_base = s->streams[i]->time_base; ctx->avoid_negative_ts = s->avoid_negative_ts; if ((ret = avio_open_dyn_buf(&ctx->pb)) < 0) goto fail; if (c->single_file) { if (c->single_file_name) dash_fill_tmpl_params(os->initfile, sizeof(os->initfile), c->single_file_name, i, 0, os->bit_rate, 0); else snprintf(os->initfile, sizeof(os->initfile), "%s-stream%d.m4s", basename, i); } else { dash_fill_tmpl_params(os->initfile, sizeof(os->initfile), c->init_seg_name, i, 0, os->bit_rate, 0); } snprintf(filename, sizeof(filename), "%s%s", c->dirname, os->initfile); ret = s->io_open(s, &os->out, filename, AVIO_FLAG_WRITE, NULL); if (ret < 0) goto fail; os->init_start_pos = 0; if (!strcmp(os->format_name, "mp4")) { av_dict_set(&opts, "movflags", "frag_custom+dash+delay_moov", 0); } else { dict_set_int(&opts, "cluster_time_limit", c->min_seg_duration / 1000, 0); dict_set_int(&opts, "cluster_size_limit", 5 * 1024 * 1024, 0); // set a large cluster size limit } if ((ret = avformat_write_header(ctx, &opts)) < 0) { goto fail; } os->ctx_inited = 1; avio_flush(ctx->pb); av_dict_free(&opts); av_log(s, AV_LOG_VERBOSE, "Representation %d init segment will be written to: %s\n", i, filename); // Flush init segment // except for mp4, since delay_moov is set and the init segment // is then flushed after the first packets if (strcmp(os->format_name, "mp4")) { flush_init_segment(s, os); } s->streams[i]->time_base = st->time_base; // If the muxer wants to shift timestamps, request to have them shifted // already before being handed to this muxer, so we don't have mismatches // between the MPD and the actual segments. s->avoid_negative_ts = ctx->avoid_negative_ts; if (st->codecpar->codec_type == AVMEDIA_TYPE_VIDEO) c->has_video = 1; set_codec_str(s, st->codecpar, os->codec_str, sizeof(os->codec_str)); os->first_pts = AV_NOPTS_VALUE; os->max_pts = AV_NOPTS_VALUE; os->last_dts = AV_NOPTS_VALUE; os->segment_index = 1; } if (!c->has_video && c->min_seg_duration <= 0) { av_log(s, AV_LOG_WARNING, "no video stream and no min seg duration set\n"); ret = AVERROR(EINVAL); } ret = write_manifest(s, 0); if (!ret) av_log(s, AV_LOG_VERBOSE, "Manifest written to: %s\n", s->filename); fail: if (ret) dash_free(s); return ret; } static int add_segment(OutputStream *os, const char *file, int64_t time, int duration, int64_t start_pos, int64_t range_length, int64_t index_length) { int err; Segment *seg; if (os->nb_segments >= os->segments_size) { os->segments_size = (os->segments_size + 1) * 2; if ((err = av_reallocp(&os->segments, sizeof(*os->segments) * os->segments_size)) < 0) { os->segments_size = 0; os->nb_segments = 0; return err; } } seg = av_mallocz(sizeof(*seg)); if (!seg) return AVERROR(ENOMEM); av_strlcpy(seg->file, file, sizeof(seg->file)); seg->time = time; seg->duration = duration; if (seg->time < 0) { // If pts<0, it is expected to be cut away with an edit list seg->duration += seg->time; seg->time = 0; } seg->start_pos = start_pos; seg->range_length = range_length; seg->index_length = index_length; os->segments[os->nb_segments++] = seg; os->segment_index++; return 0; } static void write_styp(AVIOContext *pb) { avio_wb32(pb, 24); ffio_wfourcc(pb, "styp"); ffio_wfourcc(pb, "msdh"); avio_wb32(pb, 0); /* minor */ ffio_wfourcc(pb, "msdh"); ffio_wfourcc(pb, "msix"); } static void find_index_range(AVFormatContext *s, const char *full_path, int64_t pos, int *index_length) { uint8_t buf[8]; AVIOContext *pb; int ret; ret = s->io_open(s, &pb, full_path, AVIO_FLAG_READ, NULL); if (ret < 0) return; if (avio_seek(pb, pos, SEEK_SET) != pos) { ff_format_io_close(s, &pb); return; } ret = avio_read(pb, buf, 8); ff_format_io_close(s, &pb); if (ret < 8) return; if (AV_RL32(&buf[4]) != MKTAG('s', 'i', 'd', 'x')) return; *index_length = AV_RB32(&buf[0]); } static int update_stream_extradata(AVFormatContext *s, OutputStream *os, AVCodecParameters *par) { uint8_t *extradata; if (os->ctx->streams[0]->codecpar->extradata_size || !par->extradata_size) return 0; extradata = av_malloc(par->extradata_size); if (!extradata) return AVERROR(ENOMEM); memcpy(extradata, par->extradata, par->extradata_size); os->ctx->streams[0]->codecpar->extradata = extradata; os->ctx->streams[0]->codecpar->extradata_size = par->extradata_size; set_codec_str(s, par, os->codec_str, sizeof(os->codec_str)); return 0; } static int dash_flush(AVFormatContext *s, int final, int stream) { DASHContext *c = s->priv_data; int i, ret = 0; int cur_flush_segment_index = 0; if (stream >= 0) cur_flush_segment_index = c->streams[stream].segment_index; for (i = 0; i < s->nb_streams; i++) { OutputStream *os = &c->streams[i]; char filename[1024] = "", full_path[1024], temp_path[1024]; int range_length, index_length = 0; if (!os->packets_written) continue; // Flush the single stream that got a keyframe right now. // Flush all audio streams as well, in sync with video keyframes, // but not the other video streams. if (stream >= 0 && i != stream) { if (s->streams[i]->codecpar->codec_type != AVMEDIA_TYPE_AUDIO) continue; // Make sure we don't flush audio streams multiple times, when // all video streams are flushed one at a time. if (c->has_video && os->segment_index > cur_flush_segment_index) continue; } if (!os->init_range_length) { flush_init_segment(s, os); } if (!c->single_file) { dash_fill_tmpl_params(filename, sizeof(filename), c->media_seg_name, i, os->segment_index, os->bit_rate, os->start_pts); snprintf(full_path, sizeof(full_path), "%s%s", c->dirname, filename); snprintf(temp_path, sizeof(temp_path), "%s.tmp", full_path); ret = s->io_open(s, &os->out, temp_path, AVIO_FLAG_WRITE, NULL); if (ret < 0) break; if (!strcmp(os->format_name, "mp4")) write_styp(os->ctx->pb); } else { snprintf(full_path, sizeof(full_path), "%s%s", c->dirname, os->initfile); } ret = flush_dynbuf(os, &range_length); if (ret < 0) break; os->packets_written = 0; if (c->single_file) { find_index_range(s, full_path, os->pos, &index_length); } else { ff_format_io_close(s, &os->out); ret = ff_rename(temp_path, full_path); if (ret < 0) break; } if (!os->bit_rate) { // calculate average bitrate of first segment int64_t bitrate = (int64_t) range_length * 8 * AV_TIME_BASE / (os->max_pts - os->start_pts); if (bitrate >= 0) { os->bit_rate = bitrate; snprintf(os->bandwidth_str, sizeof(os->bandwidth_str), " bandwidth=\"%d\"", os->bit_rate); } } add_segment(os, filename, os->start_pts, os->max_pts - os->start_pts, os->pos, range_length, index_length); av_log(s, AV_LOG_VERBOSE, "Representation %d media segment %d written to: %s\n", i, os->segment_index, full_path); os->pos += range_length; } if (c->window_size || (final && c->remove_at_exit)) { for (i = 0; i < s->nb_streams; i++) { OutputStream *os = &c->streams[i]; int j; int remove = os->nb_segments - c->window_size - c->extra_window_size; if (final && c->remove_at_exit) remove = os->nb_segments; if (remove > 0) { for (j = 0; j < remove; j++) { char filename[1024]; snprintf(filename, sizeof(filename), "%s%s", c->dirname, os->segments[j]->file); unlink(filename); av_free(os->segments[j]); } os->nb_segments -= remove; memmove(os->segments, os->segments + remove, os->nb_segments * sizeof(*os->segments)); } } } if (ret >= 0) ret = write_manifest(s, final); return ret; } static int dash_write_packet(AVFormatContext *s, AVPacket *pkt) { DASHContext *c = s->priv_data; AVStream *st = s->streams[pkt->stream_index]; OutputStream *os = &c->streams[pkt->stream_index]; int ret; ret = update_stream_extradata(s, os, st->codecpar); if (ret < 0) return ret; // Fill in a heuristic guess of the packet duration, if none is available. // The mp4 muxer will do something similar (for the last packet in a fragment) // if nothing is set (setting it for the other packets doesn't hurt). // By setting a nonzero duration here, we can be sure that the mp4 muxer won't // invoke its heuristic (this doesn't have to be identical to that algorithm), // so that we know the exact timestamps of fragments. if (!pkt->duration && os->last_dts != AV_NOPTS_VALUE) pkt->duration = pkt->dts - os->last_dts; os->last_dts = pkt->dts; // If forcing the stream to start at 0, the mp4 muxer will set the start // timestamps to 0. Do the same here, to avoid mismatches in duration/timestamps. if (os->first_pts == AV_NOPTS_VALUE && s->avoid_negative_ts == AVFMT_AVOID_NEG_TS_MAKE_ZERO) { pkt->pts -= pkt->dts; pkt->dts = 0; } if (os->first_pts == AV_NOPTS_VALUE) os->first_pts = pkt->pts; if ((!c->has_video || st->codecpar->codec_type == AVMEDIA_TYPE_VIDEO) && pkt->flags & AV_PKT_FLAG_KEY && os->packets_written && av_compare_ts(pkt->pts - os->start_pts, st->time_base, c->min_seg_duration, AV_TIME_BASE_Q) >= 0) { int64_t prev_duration = c->last_duration; c->last_duration = av_rescale_q(pkt->pts - os->start_pts, st->time_base, AV_TIME_BASE_Q); c->total_duration = av_rescale_q(pkt->pts - os->first_pts, st->time_base, AV_TIME_BASE_Q); if ((!c->use_timeline || !c->use_template) && prev_duration) { if (c->last_duration < prev_duration*9/10 || c->last_duration > prev_duration*11/10) { av_log(s, AV_LOG_WARNING, "Segment durations differ too much, enable use_timeline " "and use_template, or keep a stricter keyframe interval\n"); } } if ((ret = dash_flush(s, 0, pkt->stream_index)) < 0) return ret; } if (!os->packets_written) { // If we wrote a previous segment, adjust the start time of the segment // to the end of the previous one (which is the same as the mp4 muxer // does). This avoids gaps in the timeline. if (os->max_pts != AV_NOPTS_VALUE) os->start_pts = os->max_pts; else os->start_pts = pkt->pts; } if (os->max_pts == AV_NOPTS_VALUE) os->max_pts = pkt->pts + pkt->duration; else os->max_pts = FFMAX(os->max_pts, pkt->pts + pkt->duration); os->packets_written++; return ff_write_chained(os->ctx, 0, pkt, s); } static int dash_write_trailer(AVFormatContext *s) { DASHContext *c = s->priv_data; if (s->nb_streams > 0) { OutputStream *os = &c->streams[0]; // If no segments have been written so far, try to do a crude // guess of the segment duration if (!c->last_duration) c->last_duration = av_rescale_q(os->max_pts - os->start_pts, s->streams[0]->time_base, AV_TIME_BASE_Q); c->total_duration = av_rescale_q(os->max_pts - os->first_pts, s->streams[0]->time_base, AV_TIME_BASE_Q); } dash_flush(s, 1, -1); if (c->remove_at_exit) { char filename[1024]; int i; for (i = 0; i < s->nb_streams; i++) { OutputStream *os = &c->streams[i]; snprintf(filename, sizeof(filename), "%s%s", c->dirname, os->initfile); unlink(filename); } unlink(s->filename); } dash_free(s); return 0; } #define OFFSET(x) offsetof(DASHContext, x) #define E AV_OPT_FLAG_ENCODING_PARAM static const AVOption options[] = { { "adaptation_sets", "Adaptation sets. Syntax: id=0,streams=0,1,2 id=1,streams=3,4 and so on", OFFSET(adaptation_sets), AV_OPT_TYPE_STRING, { 0 }, 0, 0, AV_OPT_FLAG_ENCODING_PARAM }, { "window_size", "number of segments kept in the manifest", OFFSET(window_size), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, INT_MAX, E }, { "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 }, { "min_seg_duration", "minimum segment duration (in microseconds)", OFFSET(min_seg_duration), AV_OPT_TYPE_INT64, { .i64 = 5000000 }, 0, INT_MAX, E }, { "remove_at_exit", "remove all segments when finished", OFFSET(remove_at_exit), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, 1, E }, { "use_template", "Use SegmentTemplate instead of SegmentList", OFFSET(use_template), AV_OPT_TYPE_INT, { .i64 = 1 }, 0, 1, E }, { "use_timeline", "Use SegmentTimeline in SegmentTemplate", OFFSET(use_timeline), AV_OPT_TYPE_INT, { .i64 = 1 }, 0, 1, E }, { "single_file", "Store all segments in one file, accessed using byte ranges", OFFSET(single_file), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, 1, E }, { "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 }, { "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 }, { "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 }, { "utc_timing_url", "URL of the page that will return the UTC timestamp in ISO format", OFFSET(utc_timing_url), AV_OPT_TYPE_STRING, { 0 }, 0, 0, AV_OPT_FLAG_ENCODING_PARAM }, { NULL }, }; static const AVClass dash_class = { .class_name = "dash muxer", .item_name = av_default_item_name, .option = options, .version = LIBAVUTIL_VERSION_INT, }; AVOutputFormat ff_dash_muxer = { .name = "dash", .long_name = NULL_IF_CONFIG_SMALL("DASH Muxer"), .priv_data_size = sizeof(DASHContext), .audio_codec = AV_CODEC_ID_AAC, .video_codec = AV_CODEC_ID_H264, .flags = AVFMT_GLOBALHEADER | AVFMT_NOFILE | AVFMT_TS_NEGATIVE, .write_header = dash_write_header, .write_packet = dash_write_packet, .write_trailer = dash_write_trailer, .codec_tag = (const AVCodecTag* const []){ ff_mp4_obj_type, 0 }, .priv_class = &dash_class, };