| Line | Branch | Exec | Source |
|---|---|---|---|
| 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/rational.h" | ||
| 32 | #include "libavutil/time_internal.h" | ||
| 33 | |||
| 34 | #include "avc.h" | ||
| 35 | #include "avformat.h" | ||
| 36 | #include "avio_internal.h" | ||
| 37 | #include "internal.h" | ||
| 38 | #include "isom.h" | ||
| 39 | #include "os_support.h" | ||
| 40 | #include "url.h" | ||
| 41 | #include "dash.h" | ||
| 42 | |||
| 43 | ✗ | static DASHTmplId dash_read_tmpl_id(const char *identifier, char *format_tag, | |
| 44 | size_t format_tag_size, const char **ptr) { | ||
| 45 | const char *next_ptr; | ||
| 46 | ✗ | DASHTmplId id_type = DASH_TMPL_ID_UNDEFINED; | |
| 47 | |||
| 48 | ✗ | if (av_strstart(identifier, "$$", &next_ptr)) { | |
| 49 | ✗ | id_type = DASH_TMPL_ID_ESCAPE; | |
| 50 | ✗ | *ptr = next_ptr; | |
| 51 | ✗ | } else if (av_strstart(identifier, "$RepresentationID$", &next_ptr)) { | |
| 52 | ✗ | id_type = DASH_TMPL_ID_REP_ID; | |
| 53 | // default to basic format, as $RepresentationID$ identifiers | ||
| 54 | // are not allowed to have custom format-tags. | ||
| 55 | ✗ | av_strlcpy(format_tag, "%d", format_tag_size); | |
| 56 | ✗ | *ptr = next_ptr; | |
| 57 | } else { // the following identifiers may have an explicit format_tag | ||
| 58 | ✗ | if (av_strstart(identifier, "$Number", &next_ptr)) | |
| 59 | ✗ | id_type = DASH_TMPL_ID_NUMBER; | |
| 60 | ✗ | else if (av_strstart(identifier, "$Bandwidth", &next_ptr)) | |
| 61 | ✗ | id_type = DASH_TMPL_ID_BANDWIDTH; | |
| 62 | ✗ | else if (av_strstart(identifier, "$Time", &next_ptr)) | |
| 63 | ✗ | id_type = DASH_TMPL_ID_TIME; | |
| 64 | else | ||
| 65 | ✗ | id_type = DASH_TMPL_ID_UNDEFINED; | |
| 66 | |||
| 67 | // next parse the dash format-tag and generate a c-string format tag | ||
| 68 | // (next_ptr now points at the first '%' at the beginning of the format-tag) | ||
| 69 | ✗ | if (id_type != DASH_TMPL_ID_UNDEFINED) { | |
| 70 | ✗ | const char *number_format = (id_type == DASH_TMPL_ID_TIME) ? PRId64 : "d"; | |
| 71 | ✗ | if (next_ptr[0] == '$') { // no dash format-tag | |
| 72 | ✗ | snprintf(format_tag, format_tag_size, "%%%s", number_format); | |
| 73 | ✗ | *ptr = &next_ptr[1]; | |
| 74 | } else { | ||
| 75 | const char *width_ptr; | ||
| 76 | // only tolerate single-digit width-field (i.e. up to 9-digit width) | ||
| 77 | ✗ | if (av_strstart(next_ptr, "%0", &width_ptr) && | |
| 78 | ✗ | av_isdigit(width_ptr[0]) && | |
| 79 | ✗ | av_strstart(&width_ptr[1], "d$", &next_ptr)) { | |
| 80 | // yes, we're using a format tag to build format_tag. | ||
| 81 | ✗ | snprintf(format_tag, format_tag_size, "%s%c%s", "%0", width_ptr[0], number_format); | |
| 82 | ✗ | *ptr = next_ptr; | |
| 83 | } else { | ||
| 84 | ✗ | av_log(NULL, AV_LOG_WARNING, "Failed to parse format-tag beginning with %s. Expected either a " | |
| 85 | "closing '$' character or a format-string like '%%0[width]d', " | ||
| 86 | "where width must be a single digit\n", next_ptr); | ||
| 87 | ✗ | id_type = DASH_TMPL_ID_UNDEFINED; | |
| 88 | } | ||
| 89 | } | ||
| 90 | } | ||
| 91 | } | ||
| 92 | ✗ | return id_type; | |
| 93 | } | ||
| 94 | |||
| 95 | ✗ | void ff_dash_fill_tmpl_params(char *dst, size_t buffer_size, | |
| 96 | const char *template, int rep_id, | ||
| 97 | int number, int bit_rate, | ||
| 98 | int64_t time) { | ||
| 99 | ✗ | int dst_pos = 0; | |
| 100 | ✗ | const char *t_cur = template; | |
| 101 | ✗ | while (dst_pos < buffer_size - 1 && *t_cur) { | |
| 102 | char format_tag[7]; // May be "%d", "%0Xd", or "%0Xlld" (for $Time$), where X is in [0-9] | ||
| 103 | ✗ | int n = 0; | |
| 104 | DASHTmplId id_type; | ||
| 105 | ✗ | const char *t_next = strchr(t_cur, '$'); // copy over everything up to the first '$' character | |
| 106 | ✗ | if (t_next) { | |
| 107 | ✗ | int num_copy_bytes = FFMIN(t_next - t_cur, buffer_size - dst_pos - 1); | |
| 108 | ✗ | av_strlcpy(&dst[dst_pos], t_cur, num_copy_bytes + 1); | |
| 109 | // advance | ||
| 110 | ✗ | dst_pos += num_copy_bytes; | |
| 111 | ✗ | t_cur = t_next; | |
| 112 | } else { // no more DASH identifiers to substitute - just copy the rest over and break | ||
| 113 | ✗ | av_strlcpy(&dst[dst_pos], t_cur, buffer_size - dst_pos); | |
| 114 | ✗ | break; | |
| 115 | } | ||
| 116 | |||
| 117 | ✗ | if (dst_pos >= buffer_size - 1 || !*t_cur) | |
| 118 | break; | ||
| 119 | |||
| 120 | // t_cur is now pointing to a '$' character | ||
| 121 | ✗ | id_type = dash_read_tmpl_id(t_cur, format_tag, sizeof(format_tag), &t_next); | |
| 122 | ✗ | switch (id_type) { | |
| 123 | ✗ | case DASH_TMPL_ID_ESCAPE: | |
| 124 | ✗ | av_strlcpy(&dst[dst_pos], "$", 2); | |
| 125 | ✗ | n = 1; | |
| 126 | ✗ | break; | |
| 127 | ✗ | case DASH_TMPL_ID_REP_ID: | |
| 128 | ✗ | n = snprintf(&dst[dst_pos], buffer_size - dst_pos, format_tag, rep_id); | |
| 129 | ✗ | break; | |
| 130 | ✗ | case DASH_TMPL_ID_NUMBER: | |
| 131 | ✗ | n = snprintf(&dst[dst_pos], buffer_size - dst_pos, format_tag, number); | |
| 132 | ✗ | break; | |
| 133 | ✗ | case DASH_TMPL_ID_BANDWIDTH: | |
| 134 | ✗ | n = snprintf(&dst[dst_pos], buffer_size - dst_pos, format_tag, bit_rate); | |
| 135 | ✗ | break; | |
| 136 | ✗ | case DASH_TMPL_ID_TIME: | |
| 137 | ✗ | n = snprintf(&dst[dst_pos], buffer_size - dst_pos, format_tag, time); | |
| 138 | ✗ | break; | |
| 139 | ✗ | case DASH_TMPL_ID_UNDEFINED: | |
| 140 | // copy over one byte and advance | ||
| 141 | ✗ | av_strlcpy(&dst[dst_pos], t_cur, 2); | |
| 142 | ✗ | n = 1; | |
| 143 | ✗ | t_next = &t_cur[1]; | |
| 144 | ✗ | break; | |
| 145 | } | ||
| 146 | // t_next points just past the processed identifier | ||
| 147 | // n is the number of bytes that were attempted to be written to dst | ||
| 148 | // (may have failed to write all because buffer_size). | ||
| 149 | |||
| 150 | // advance | ||
| 151 | ✗ | dst_pos += FFMIN(n, buffer_size - dst_pos - 1); | |
| 152 | ✗ | t_cur = t_next; | |
| 153 | } | ||
| 154 | ✗ | } | |
| 155 | |||
| 156 | |||
| 157 |