Edit File: timecode.h
/* * 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 header */ #ifndef AVUTIL_TIMECODE_H #define AVUTIL_TIMECODE_H #include <stdint.h> #include "rational.h" #define AV_TIMECODE_STR_SIZE 16 enum AVTimecodeFlag { AV_TIMECODE_FLAG_DROPFRAME = 1<<0, ///< timecode is drop frame AV_TIMECODE_FLAG_24HOURSMAX = 1<<1, ///< timecode wraps after 24 hours AV_TIMECODE_FLAG_ALLOWNEGATIVE = 1<<2, ///< negative time values are allowed }; typedef struct { int start; ///< timecode frame start (first base frame number) uint32_t flags; ///< flags such as drop frame, +24 hours support, ... AVRational rate; ///< frame rate in rational form unsigned fps; ///< frame per second; must be consistent with the rate field } AVTimecode; /** * Adjust frame number for NTSC drop frame time code. * * @param framenum frame number to adjust * @param fps frame per second, 30 or 60 * @return adjusted frame number * @warning adjustment is only valid in NTSC 29.97 and 59.94 */ int av_timecode_adjust_ntsc_framenum2(int framenum, int fps); /** * Convert frame number to SMPTE 12M binary representation. * * @param tc timecode data correctly initialized * @param framenum frame number * @return the SMPTE binary representation * * @note Frame number adjustment is automatically done in case of drop timecode, * you do NOT have to call av_timecode_adjust_ntsc_framenum2(). * @note The frame number is relative to tc->start. * @note Color frame (CF), binary group flags (BGF) and biphase mark polarity * correction (PC) bits are set to zero. */ uint32_t av_timecode_get_smpte_from_framenum(const AVTimecode *tc, int framenum); /** * Load timecode string in buf. * * @param buf destination buffer, must be at least AV_TIMECODE_STR_SIZE long * @param tc timecode data correctly initialized * @param framenum frame number * @return the buf parameter * * @note Timecode representation can be a negative timecode and have more than * 24 hours, but will only be honored if the flags are correctly set. * @note The frame number is relative to tc->start. */ char *av_timecode_make_string(const AVTimecode *tc, char *buf, int framenum); /** * Get the timecode string from the SMPTE timecode format. * * @param buf destination buffer, must be at least AV_TIMECODE_STR_SIZE long * @param tcsmpte the 32-bit SMPTE timecode * @param prevent_df prevent the use of a drop flag when it is known the DF bit * is arbitrary * @return the buf parameter */ char *av_timecode_make_smpte_tc_string(char *buf, uint32_t tcsmpte, int prevent_df); /** * Get the timecode string from the 25-bit timecode format (MPEG GOP format). * * @param buf destination buffer, must be at least AV_TIMECODE_STR_SIZE long * @param tc25bit the 25-bits timecode * @return the buf parameter */ char *av_timecode_make_mpeg_tc_string(char *buf, uint32_t tc25bit); /** * Init a timecode struct with the passed parameters. * * @param log_ctx a pointer to an arbitrary struct of which the first field * is a pointer to an AVClass struct (used for av_log) * @param tc pointer to an allocated AVTimecode * @param rate frame rate in rational form * @param flags miscellaneous flags such as drop frame, +24 hours, ... * (see AVTimecodeFlag) * @param frame_start the first frame number * @return 0 on success, AVERROR otherwise */ int av_timecode_init(AVTimecode *tc, AVRational rate, int flags, int frame_start, void *log_ctx); /** * Parse timecode representation (hh:mm:ss[:;.]ff). * * @param log_ctx a pointer to an arbitrary struct of which the first field is a * pointer to an AVClass struct (used for av_log). * @param tc pointer to an allocated AVTimecode * @param rate frame rate in rational form * @param str timecode string which will determine the frame start * @return 0 on success, AVERROR otherwise */ int av_timecode_init_from_string(AVTimecode *tc, AVRational rate, const char *str, void *log_ctx); /** * Check if the timecode feature is available for the given frame rate * * @return 0 if supported, <0 otherwise */ int av_timecode_check_frame_rate(AVRational rate); #endif /* AVUTIL_TIMECODE_H */