/* * Copyright (c) 2006 Smartjog S.A.S, Baptiste Coudurier * Copyright (c) 2011-2012 Smartjog S.A.S, Clément Bœsch * * This file is part of FFmpeg. * * FFmpeg 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. * * FFmpeg 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 FFmpeg; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ /** * @file * Timecode helpers * A few references: * https://en.wikipedia.org/wiki/SMPTE_time_code * http://www.dropframetimecode.org */ #include #include "timecode.h" #include "log.h" #include "error.h" int av_timecode_adjust_ntsc_framenum(int framenum) { /* only works for NTSC 29.97 */ int d = framenum / 17982; int m = framenum % 17982; //if (m < 2) m += 2; /* not needed since -2,-1 / 1798 in C returns 0 */ return framenum + 18 * d + 2 * ((m - 2) / 1798); } uint32_t av_timecode_get_smpte_from_framenum(const AVTimecode *tc, int framenum) { unsigned fps = tc->fps; int drop = !!(tc->flags & AV_TIMECODE_FLAG_DROPFRAME); int hh, mm, ss, ff; framenum += tc->start; if (drop) framenum = av_timecode_adjust_ntsc_framenum(framenum); ff = framenum % fps; ss = framenum / fps % 60; mm = framenum / (fps*60) % 60; hh = framenum / (fps*3600) % 24; return 0 << 31 | // color frame flag (0: unsync mode, 1: sync mode) drop << 30 | // drop frame flag (0: non drop, 1: drop) (ff / 10) << 28 | // tens of frames (ff % 10) << 24 | // units of frames 0 << 23 | // PC (NTSC) or BGF0 (PAL) (ss / 10) << 20 | // tens of seconds (ss % 10) << 16 | // units of seconds 0 << 15 | // BGF0 (NTSC) or BGF2 (PAL) (mm / 10) << 12 | // tens of minutes (mm % 10) << 8 | // units of minutes 0 << 7 | // BGF2 (NTSC) or PC (PAL) 0 << 6 | // BGF1 (hh / 10) << 4 | // tens of hours (hh % 10); // units of hours } char *av_timecode_make_string(const AVTimecode *tc, char *buf, int framenum) { int fps = tc->fps; int drop = tc->flags & AV_TIMECODE_FLAG_DROPFRAME; int hh, mm, ss, ff, neg = 0; framenum += tc->start; if (drop) framenum = av_timecode_adjust_ntsc_framenum(framenum); if (framenum < 0) { framenum = -framenum; neg = tc->flags & AV_TIMECODE_FLAG_ALLOWNEGATIVE; } ff = framenum % fps; ss = framenum / fps % 60; mm = framenum / (fps*60) % 60; hh = framenum / (fps*3600); if (tc->flags & AV_TIMECODE_FLAG_24HOURSMAX) hh = hh % 24; snprintf(buf, AV_TIMECODE_STR_SIZE, "%s%02d:%02d:%02d%c%02d", neg ? "-" : "", hh, mm, ss, drop ? ';' : ':', ff); return buf; } static unsigned bcd2uint(uint8_t bcd) { unsigned low = bcd & 0xf; unsigned high = bcd >> 4; if (low > 9 || high > 9) return 0; return low + 10*high; } char *av_timecode_make_smpte_tc_string(char *buf, uint32_t tcsmpte, int prevent_df) { unsigned hh = bcd2uint(tcsmpte & 0x3f); // 6-bit hours unsigned mm = bcd2uint(tcsmpte>>8 & 0x7f); // 7-bit minutes unsigned ss = bcd2uint(tcsmpte>>16 & 0x7f); // 7-bit seconds unsigned ff = bcd2uint(tcsmpte>>24 & 0x3f); // 6-bit frames unsigned drop = tcsmpte & 1<<30 && !prevent_df; // 1-bit drop if not arbitrary bit snprintf(buf, AV_TIMECODE_STR_SIZE, "%02u:%02u:%02u%c%02u", hh, mm, ss, drop ? ';' : ':', ff); return buf; } char *av_timecode_make_mpeg_tc_string(char *buf, uint32_t tc25bit) { snprintf(buf, AV_TIMECODE_STR_SIZE, "%02u:%02u:%02u%c%02u", tc25bit>>19 & 0x1f, // 5-bit hours tc25bit>>13 & 0x3f, // 6-bit minutes tc25bit>>6 & 0x3f, // 6-bit seconds tc25bit & 1<<24 ? ';' : ':', // 1-bit drop flag tc25bit & 0x3f); // 6-bit frames return buf; } static int check_timecode(void *log_ctx, AVTimecode *tc) { if (tc->fps <= 0) { av_log(log_ctx, AV_LOG_ERROR, "Timecode frame rate must be specified\n"); return AVERROR(EINVAL); } if ((tc->flags & AV_TIMECODE_FLAG_DROPFRAME) && tc->fps != 30) { av_log(log_ctx, AV_LOG_ERROR, "Drop frame is only allowed with 30000/1001 FPS\n"); return AVERROR(EINVAL); } switch (tc->fps) { case 24: case 25: case 30: return 0; default: av_log(log_ctx, AV_LOG_ERROR, "Timecode frame rate not supported\n"); return AVERROR_PATCHWELCOME; } } static int fps_from_frame_rate(AVRational rate) { if (!rate.den || !rate.num) return -1; return (rate.num + rate.den/2) / rate.den; } int av_timecode_init(AVTimecode *tc, AVRational rate, int flags, int frame_start, void *log_ctx) { memset(tc, 0, sizeof(*tc)); tc->start = frame_start; tc->flags = flags; tc->rate = rate; tc->fps = fps_from_frame_rate(rate); return check_timecode(log_ctx, tc); } int av_timecode_init_from_string(AVTimecode *tc, AVRational rate, const char *str, void *log_ctx) { char c; int hh, mm, ss, ff, ret; if (sscanf(str, "%d:%d:%d%c%d", &hh, &mm, &ss, &c, &ff) != 5) { av_log(log_ctx, AV_LOG_ERROR, "Unable to parse timecode, " "syntax: hh:mm:ss[:;.]ff\n"); return AVERROR_INVALIDDATA; } memset(tc, 0, sizeof(*tc)); tc->flags = c != ':' ? AV_TIMECODE_FLAG_DROPFRAME : 0; // drop if ';', '.', ... tc->rate = rate; tc->fps = fps_from_frame_rate(rate); ret = check_timecode(log_ctx, tc); if (ret < 0) return ret; tc->start = (hh*3600 + mm*60 + ss) * tc->fps + ff; if (tc->flags & AV_TIMECODE_FLAG_DROPFRAME) { /* adjust frame number */ int tmins = 60*hh + mm; tc->start -= 2 * (tmins - tmins/10); } return 0; }