/* * Copyright (c) 2006 Smartjog S.A.S, Baptiste Coudurier <baptiste.coudurier@gmail.com> * Copyright (c) 2011-2012 Smartjog S.A.S, Clément Bœsch <clement.boesch@smartjog.com> * * 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 * @see https://en.wikipedia.org/wiki/SMPTE_time_code * @see http://www.dropframetimecode.org */ #include <stdio.h>#include "timecode.h"#include "log.h"#include "error.h" int av_timecode_adjust_ntsc_framenum2(int framenum, int fps){    /* only works for NTSC 29.97 and 59.94 */    int drop_frames = 0;    int d, m, frames_per_10mins;     if (fps == 30) {        drop_frames = 2;        frames_per_10mins = 17982;    } else if (fps == 60) {        drop_frames = 4;        frames_per_10mins = 35964;    } else        return framenum;     d = framenum / frames_per_10mins;    m = framenum % frames_per_10mins;     return framenum + 9 * drop_frames * d + drop_frames * ((m - drop_frames) / (frames_per_10mins / 10));} 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_framenum2(framenum, tc->fps);    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_framenum2(framenum, fps);    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,             "%02"PRIu32":%02"PRIu32":%02"PRIu32"%c%02"PRIu32,             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_fps(int fps){    int i;    static const int supported_fps[] = {        24, 25, 30, 48, 50, 60, 100, 120, 150,    };     for (i = 0; i < FF_ARRAY_ELEMS(supported_fps); i++)        if (fps == supported_fps[i])            return 0;    return -1;} static int check_timecode(void *log_ctx, AVTimecode *tc){    if ((int)tc->fps <= 0) {        av_log(log_ctx, AV_LOG_ERROR, "Valid timecode frame rate must be specified. Minimum value is 1\n");        return AVERROR(EINVAL);    }    if ((tc->flags & AV_TIMECODE_FLAG_DROPFRAME) && tc->fps != 30 && tc->fps != 60) {        av_log(log_ctx, AV_LOG_ERROR, "Drop frame is only allowed with 30000/1001 or 60000/1001 FPS\n");        return AVERROR(EINVAL);    }    if (check_fps(tc->fps) < 0) {        av_log(log_ctx, AV_LOG_WARNING, "Using non-standard frame rate %d/%d\n",               tc->rate.num, tc->rate.den);    }    return 0;} 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_check_frame_rate(AVRational rate){    return check_fps(fps_from_frame_rate(rate));} 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 -= (tc->fps == 30 ? 2 : 4) * (tmins - tmins/10);    }    return 0;}