1/* 2 * Copyright (c) 2006 Smartjog S.A.S, Baptiste Coudurier <baptiste.coudurier@gmail.com> 3 * Copyright (c) 2011-2012 Smartjog S.A.S, Cl��ment B��sch <clement.boesch@smartjog.com> 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/** 23 * @file 24 * Timecode helpers 25 * @see https://en.wikipedia.org/wiki/SMPTE_time_code 26 * @see http://www.dropframetimecode.org 27 */ 28 29#include <stdio.h> 30#include "timecode.h" 31#include "log.h" 32#include "error.h" 33 34int av_timecode_adjust_ntsc_framenum2(int framenum, int fps) 35{ 36 /* only works for NTSC 29.97 and 59.94 */ 37 int drop_frames = 0; 38 int d, m, frames_per_10mins; 39 40 if (fps == 30) { 41 drop_frames = 2; 42 frames_per_10mins = 17982; 43 } else if (fps == 60) { 44 drop_frames = 4; 45 frames_per_10mins = 35964; 46 } else 47 return framenum; 48 49 d = framenum / frames_per_10mins; 50 m = framenum % frames_per_10mins; 51 52 return framenum + 9 * drop_frames * d + drop_frames * ((m - drop_frames) / (frames_per_10mins / 10)); 53} 54 55uint32_t av_timecode_get_smpte_from_framenum(const AVTimecode *tc, int framenum) 56{ 57 unsigned fps = tc->fps; 58 int drop = !!(tc->flags & AV_TIMECODE_FLAG_DROPFRAME); 59 int hh, mm, ss, ff; 60 61 framenum += tc->start; 62 if (drop) 63 framenum = av_timecode_adjust_ntsc_framenum2(framenum, tc->fps); 64 ff = framenum % fps; 65 ss = framenum / fps % 60; 66 mm = framenum / (fps*60) % 60; 67 hh = framenum / (fps*3600) % 24; 68 return 0 << 31 | // color frame flag (0: unsync mode, 1: sync mode) 69 drop << 30 | // drop frame flag (0: non drop, 1: drop) 70 (ff / 10) << 28 | // tens of frames 71 (ff % 10) << 24 | // units of frames 72 0 << 23 | // PC (NTSC) or BGF0 (PAL) 73 (ss / 10) << 20 | // tens of seconds 74 (ss % 10) << 16 | // units of seconds 75 0 << 15 | // BGF0 (NTSC) or BGF2 (PAL) 76 (mm / 10) << 12 | // tens of minutes 77 (mm % 10) << 8 | // units of minutes 78 0 << 7 | // BGF2 (NTSC) or PC (PAL) 79 0 << 6 | // BGF1 80 (hh / 10) << 4 | // tens of hours 81 (hh % 10); // units of hours 82} 83 84char *av_timecode_make_string(const AVTimecode *tc, char *buf, int framenum) 85{ 86 int fps = tc->fps; 87 int drop = tc->flags & AV_TIMECODE_FLAG_DROPFRAME; 88 int hh, mm, ss, ff, neg = 0; 89 90 framenum += tc->start; 91 if (drop) 92 framenum = av_timecode_adjust_ntsc_framenum2(framenum, fps); 93 if (framenum < 0) { 94 framenum = -framenum; 95 neg = tc->flags & AV_TIMECODE_FLAG_ALLOWNEGATIVE; 96 } 97 ff = framenum % fps; 98 ss = framenum / fps % 60; 99 mm = framenum / (fps*60) % 60; 100 hh = framenum / (fps*3600); 101 if (tc->flags & AV_TIMECODE_FLAG_24HOURSMAX) 102 hh = hh % 24; 103 snprintf(buf, AV_TIMECODE_STR_SIZE, "%s%02d:%02d:%02d%c%02d", 104 neg ? "-" : "", 105 hh, mm, ss, drop ? ';' : ':', ff); 106 return buf; 107} 108 109static unsigned bcd2uint(uint8_t bcd) 110{ 111 unsigned low = bcd & 0xf; 112 unsigned high = bcd >> 4; 113 if (low > 9 || high > 9) 114 return 0; 115 return low + 10*high; 116} 117 118char *av_timecode_make_smpte_tc_string(char *buf, uint32_t tcsmpte, int prevent_df) 119{ 120 unsigned hh = bcd2uint(tcsmpte & 0x3f); // 6-bit hours 121 unsigned mm = bcd2uint(tcsmpte>>8 & 0x7f); // 7-bit minutes 122 unsigned ss = bcd2uint(tcsmpte>>16 & 0x7f); // 7-bit seconds 123 unsigned ff = bcd2uint(tcsmpte>>24 & 0x3f); // 6-bit frames 124 unsigned drop = tcsmpte & 1<<30 && !prevent_df; // 1-bit drop if not arbitrary bit 125 snprintf(buf, AV_TIMECODE_STR_SIZE, "%02u:%02u:%02u%c%02u", 126 hh, mm, ss, drop ? ';' : ':', ff); 127 return buf; 128} 129 130char *av_timecode_make_mpeg_tc_string(char *buf, uint32_t tc25bit) 131{ 132 snprintf(buf, AV_TIMECODE_STR_SIZE, "%02u:%02u:%02u%c%02u", 133 tc25bit>>19 & 0x1f, // 5-bit hours 134 tc25bit>>13 & 0x3f, // 6-bit minutes 135 tc25bit>>6 & 0x3f, // 6-bit seconds 136 tc25bit & 1<<24 ? ';' : ':', // 1-bit drop flag 137 tc25bit & 0x3f); // 6-bit frames 138 return buf; 139} 140 141static int check_fps(int fps) 142{ 143 int i; 144 static const int supported_fps[] = {24, 25, 30, 48, 50, 60}; 145 146 for (i = 0; i < FF_ARRAY_ELEMS(supported_fps); i++) 147 if (fps == supported_fps[i]) 148 return 0; 149 return -1; 150} 151 152static int check_timecode(void *log_ctx, AVTimecode *tc) 153{ 154 if (tc->fps <= 0) { 155 av_log(log_ctx, AV_LOG_ERROR, "Timecode frame rate must be specified\n"); 156 return AVERROR(EINVAL); 157 } 158 if ((tc->flags & AV_TIMECODE_FLAG_DROPFRAME) && tc->fps != 30 && tc->fps != 60) { 159 av_log(log_ctx, AV_LOG_ERROR, "Drop frame is only allowed with 30000/1001 or 60000/1001 FPS\n"); 160 return AVERROR(EINVAL); 161 } 162 if (check_fps(tc->fps) < 0) { 163 av_log(log_ctx, AV_LOG_ERROR, "Timecode frame rate %d/%d not supported\n", 164 tc->rate.num, tc->rate.den); 165 return AVERROR_PATCHWELCOME; 166 } 167 return 0; 168} 169 170static int fps_from_frame_rate(AVRational rate) 171{ 172 if (!rate.den || !rate.num) 173 return -1; 174 return (rate.num + rate.den/2) / rate.den; 175} 176 177int av_timecode_check_frame_rate(AVRational rate) 178{ 179 return check_fps(fps_from_frame_rate(rate)); 180} 181 182int av_timecode_init(AVTimecode *tc, AVRational rate, int flags, int frame_start, void *log_ctx) 183{ 184 memset(tc, 0, sizeof(*tc)); 185 tc->start = frame_start; 186 tc->flags = flags; 187 tc->rate = rate; 188 tc->fps = fps_from_frame_rate(rate); 189 return check_timecode(log_ctx, tc); 190} 191 192int av_timecode_init_from_string(AVTimecode *tc, AVRational rate, const char *str, void *log_ctx) 193{ 194 char c; 195 int hh, mm, ss, ff, ret; 196 197 if (sscanf(str, "%d:%d:%d%c%d", &hh, &mm, &ss, &c, &ff) != 5) { 198 av_log(log_ctx, AV_LOG_ERROR, "Unable to parse timecode, " 199 "syntax: hh:mm:ss[:;.]ff\n"); 200 return AVERROR_INVALIDDATA; 201 } 202 203 memset(tc, 0, sizeof(*tc)); 204 tc->flags = c != ':' ? AV_TIMECODE_FLAG_DROPFRAME : 0; // drop if ';', '.', ... 205 tc->rate = rate; 206 tc->fps = fps_from_frame_rate(rate); 207 208 ret = check_timecode(log_ctx, tc); 209 if (ret < 0) 210 return ret; 211 212 tc->start = (hh*3600 + mm*60 + ss) * tc->fps + ff; 213 if (tc->flags & AV_TIMECODE_FLAG_DROPFRAME) { /* adjust frame number */ 214 int tmins = 60*hh + mm; 215 tc->start -= 2 * (tmins - tmins/10); 216 } 217 return 0; 218} 219