ffmpeg/libavcodec/timecode.h

103 lines
3.8 KiB
C

/*
* Copyright (C) 2006 Smartjog S.A.S, Baptiste Coudurier <baptiste.coudurier@gmail.com>
* Copyright (C) 2011 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 AVCODEC_TIMECODE_H
#define AVCODEC_TIMECODE_H
#include <stdint.h>
#include "avcodec.h"
#include "libavutil/rational.h"
#define TIMECODE_OPT(ctx, flags) \
"timecode", "set timecode value following hh:mm:ss[:;.]ff format, " \
"use ';' or '.' before frame number for drop frame", \
offsetof(ctx, tc.str), \
AV_OPT_TYPE_STRING, {.str=NULL}, CHAR_MIN, CHAR_MAX, flags
struct ff_timecode {
char *str; ///< string following the hh:mm:ss[:;.]ff format
int start; ///< timecode frame start
int drop; ///< drop flag (1 if drop, else 0)
AVRational rate; ///< Frame rate in rationnal form
};
/**
* @brief Adjust frame number for NTSC drop frame time code
* @param frame_num Actual frame number to adjust
* @return Adjusted frame number
* @warning Adjustment is only valid in NTSC 29.97
*/
int avpriv_framenum_to_drop_timecode(int frame_num);
/**
* @brief Convert frame id (timecode) to SMPTE 12M binary representation
* @param frame Frame number
* @param fps Frame rate
* @param drop Drop flag
* @return The actual binary representation
*/
uint32_t avpriv_framenum_to_smpte_timecode(unsigned frame, int fps, int drop);
/**
* @brief Load timecode string in buf
* @param buf Destination buffer
* @param tc Timecode struct pointer
* @param frame Frame id (timecode frame is computed with tc->start+frame)
* @return a pointer to the buf parameter
* @note timecode representation can be a negative timecode and have
* more than 24 hours.
* @note buf must have enough space to store the timecode representation: 16
* bytes is the minimum required size.
*/
char *avpriv_timecode_to_string(char *buf, const struct ff_timecode *tc, unsigned frame);
/**
* Check if timecode rate is valid and consistent with the drop flag.
*
* @return 0 on success, negative value on failure
*/
int avpriv_check_timecode_rate(void *avcl, AVRational rate, int drop);
/**
* Parse SMTPE 12M time representation (hh:mm:ss[:;.]ff). str and rate fields
* from tc struct must be set.
*
* @param avcl A pointer to an arbitrary struct of which the first field is a
* pointer to an AVClass struct (used for av_log).
* @param tc Timecode struct pointer
* @return 0 on success, negative value on failure
* @warning Adjustement is only valid in NTSC 29.97
*/
int avpriv_init_smpte_timecode(void *avcl, struct ff_timecode *tc);
#if FF_API_OLD_TIMECODE
attribute_deprecated int ff_framenum_to_drop_timecode(int frame_num);
attribute_deprecated uint32_t ff_framenum_to_smtpe_timecode(unsigned frame, int fps, int drop);
attribute_deprecated int ff_init_smtpe_timecode(void *avcl, struct ff_timecode *tc);
#endif
#endif /* AVCODEC_TIMECODE_H */