ffmpeg/libavformat/demux.h

242 lines
8.1 KiB
C

/*
* copyright (c) 2001 Fabrice Bellard
*
* 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
*/
#ifndef AVFORMAT_DEMUX_H
#define AVFORMAT_DEMUX_H
#include <stdint.h>
#include "libavutil/rational.h"
#include "libavcodec/packet.h"
#include "avformat.h"
#define MAX_STD_TIMEBASES (30*12+30+3+6)
typedef struct FFStreamInfo {
int64_t last_dts;
int64_t duration_gcd;
int duration_count;
int64_t rfps_duration_sum;
double (*duration_error)[2][MAX_STD_TIMEBASES];
int64_t codec_info_duration;
int64_t codec_info_duration_fields;
int frame_delay_evidence;
/**
* 0 -> decoder has not been searched for yet.
* >0 -> decoder found
* <0 -> decoder with codec_id == -found_decoder has not been found
*/
int found_decoder;
int64_t last_duration;
/**
* Those are used for average framerate estimation.
*/
int64_t fps_first_dts;
int fps_first_dts_idx;
int64_t fps_last_dts;
int fps_last_dts_idx;
} FFStreamInfo;
/**
* Returned by demuxers to indicate that data was consumed but discarded
* (ignored streams or junk data). The framework will re-call the demuxer.
*/
#define FFERROR_REDO FFERRTAG('R','E','D','O')
#define RELATIVE_TS_BASE (INT64_MAX - (1LL << 48))
static av_always_inline int is_relative(int64_t ts)
{
return ts > (RELATIVE_TS_BASE - (1LL << 48));
}
/**
* Wrap a given time stamp, if there is an indication for an overflow
*
* @param st stream
* @param timestamp the time stamp to wrap
* @return resulting time stamp
*/
int64_t ff_wrap_timestamp(const AVStream *st, int64_t timestamp);
/**
* Read a transport packet from a media file.
*
* @param s media file handle
* @param pkt is filled
* @return 0 if OK, AVERROR_xxx on error
*/
int ff_read_packet(AVFormatContext *s, AVPacket *pkt);
void ff_read_frame_flush(AVFormatContext *s);
/**
* Perform a binary search using av_index_search_timestamp() and
* AVInputFormat.read_timestamp().
*
* @param target_ts target timestamp in the time base of the given stream
* @param stream_index stream number
*/
int ff_seek_frame_binary(AVFormatContext *s, int stream_index,
int64_t target_ts, int flags);
/**
* Update cur_dts of all streams based on the given timestamp and AVStream.
*
* Stream ref_st unchanged, others set cur_dts in their native time base.
* Only needed for timestamp wrapping or if (dts not set and pts!=dts).
* @param timestamp new dts expressed in time_base of param ref_st
* @param ref_st reference stream giving time_base of param timestamp
*/
void avpriv_update_cur_dts(AVFormatContext *s, AVStream *ref_st, int64_t timestamp);
int ff_find_last_ts(AVFormatContext *s, int stream_index, int64_t *ts, int64_t *pos,
int64_t (*read_timestamp)(struct AVFormatContext *, int , int64_t *, int64_t ));
/**
* Perform a binary search using read_timestamp().
*
* @param target_ts target timestamp in the time base of the given stream
* @param stream_index stream number
*/
int64_t ff_gen_search(AVFormatContext *s, int stream_index,
int64_t target_ts, int64_t pos_min,
int64_t pos_max, int64_t pos_limit,
int64_t ts_min, int64_t ts_max,
int flags, int64_t *ts_ret,
int64_t (*read_timestamp)(struct AVFormatContext *, int , int64_t *, int64_t ));
/**
* Internal version of av_index_search_timestamp
*/
int ff_index_search_timestamp(const AVIndexEntry *entries, int nb_entries,
int64_t wanted_timestamp, int flags);
/**
* Internal version of av_add_index_entry
*/
int ff_add_index_entry(AVIndexEntry **index_entries,
int *nb_index_entries,
unsigned int *index_entries_allocated_size,
int64_t pos, int64_t timestamp, int size, int distance, int flags);
void ff_configure_buffers_for_index(AVFormatContext *s, int64_t time_tolerance);
/**
* Ensure the index uses less memory than the maximum specified in
* AVFormatContext.max_index_size by discarding entries if it grows
* too large.
*/
void ff_reduce_index(AVFormatContext *s, int stream_index);
/**
* add frame for rfps calculation.
*
* @param dts timestamp of the i-th frame
* @return 0 if OK, AVERROR_xxx on error
*/
int ff_rfps_add_frame(AVFormatContext *ic, AVStream *st, int64_t dts);
void ff_rfps_calculate(AVFormatContext *ic);
/**
* Rescales a timestamp and the endpoints of an interval to which the temstamp
* belongs, from a timebase `tb_in` to a timebase `tb_out`.
*
* The upper (lower) bound of the output interval is rounded up (down) such that
* the output interval always falls within the intput interval. The timestamp is
* rounded to the nearest integer and halfway cases away from zero, and can
* therefore fall outside of the output interval.
*
* Useful to simplify the rescaling of the arguments of AVInputFormat::read_seek2()
*
* @param[in] tb_in Timebase of the input `min_ts`, `ts` and `max_ts`
* @param[in] tb_out Timebase of the ouput `min_ts`, `ts` and `max_ts`
* @param[in,out] min_ts Lower bound of the interval
* @param[in,out] ts Timestamp
* @param[in,out] max_ts Upper bound of the interval
*/
void ff_rescale_interval(AVRational tb_in, AVRational tb_out,
int64_t *min_ts, int64_t *ts, int64_t *max_ts);
void avpriv_stream_set_need_parsing(AVStream *st, enum AVStreamParseType type);
/**
* Add a new chapter.
*
* @param s media file handle
* @param id unique ID for this chapter
* @param start chapter start time in time_base units
* @param end chapter end time in time_base units
* @param title chapter title
*
* @return AVChapter or NULL on error
*/
AVChapter *avpriv_new_chapter(AVFormatContext *s, int64_t id, AVRational time_base,
int64_t start, int64_t end, const char *title);
/**
* Add an attached pic to an AVStream.
*
* @param st if set, the stream to add the attached pic to;
* if unset, a new stream will be added to s.
* @param pb AVIOContext to read data from if buf is unset.
* @param buf if set, it contains the data and size information to be used
* for the attached pic; if unset, data is read from pb.
* @param size the size of the data to read if buf is unset.
*
* @return 0 on success, < 0 on error. On error, this function removes
* the stream it has added (if any).
*/
int ff_add_attached_pic(AVFormatContext *s, AVStream *st, AVIOContext *pb,
AVBufferRef **buf, int size);
/**
* Add side data to a packet for changing parameters to the given values.
* Parameters set to 0 aren't included in the change.
*/
int ff_add_param_change(AVPacket *pkt, int32_t channels,
uint64_t channel_layout, int32_t sample_rate,
int32_t width, int32_t height);
/**
* Generate standard extradata for AVC-Intra based on width/height and field
* order.
*/
int ff_generate_avci_extradata(AVStream *st);
/**
* Allocate extradata with additional AV_INPUT_BUFFER_PADDING_SIZE at end
* which is always set to 0 and fill it from pb.
*
* @param size size of extradata
* @return >= 0 if OK, AVERROR_xxx on error
*/
int ff_get_extradata(void *logctx, AVCodecParameters *par, AVIOContext *pb, int size);
/**
* Find stream index based on format-specific stream ID
* @return stream index, or < 0 on error
*/
int ff_find_stream_index(const AVFormatContext *s, int id);
#endif /* AVFORMAT_DEMUX_H */