subtitles.h File Reference

#include <stdint.h>
#include <stddef.h>
#include "avformat.h"
#include "libavutil/bprint.h"

Go to the source code of this file.

Data Structures
struct	FFTextReader
struct	FFDemuxSubtitlesQueue

Enumerations
enum	sub_sort { SUB_SORT_TS_POS = 0, SUB_SORT_POS_TS }
enum	ff_utf_type { FF_UTF_8, FF_UTF16LE, FF_UTF16BE }

Functions
void	ff_text_init_avio (void *s, FFTextReader *r, AVIOContext *pb)
	Initialize the FFTextReader from the given AVIOContext.
void	ff_text_init_buf (FFTextReader *r, void *buf, size_t size)
	Similar to ff_text_init_avio(), but sets it up to read from a bounded buffer.
int64_t	ff_text_pos (FFTextReader *r)
	Return the byte position of the next byte returned by ff_text_r8().
int	ff_text_r8 (FFTextReader *r)
	Return the next byte.
int	ff_text_eof (FFTextReader *r)
	Return non-zero if EOF was reached.
int	ff_text_peek_r8 (FFTextReader *r)
	Like ff_text_r8(), but don't remove the byte from the buffer.
void	ff_text_read (FFTextReader *r, char *buf, size_t size)
	Read the given number of bytes (in UTF-8).
AVPacket *	ff_subtitles_queue_insert (FFDemuxSubtitlesQueue *q, const uint8_t *event, int len, int merge)
	Insert a new subtitle event.
void	ff_subtitles_queue_finalize (FFDemuxSubtitlesQueue *q)
	Set missing durations and sort subtitles by PTS, and then byte position.
int	ff_subtitles_queue_read_packet (FFDemuxSubtitlesQueue *q, AVPacket *pkt)
	Generic read_packet() callback for subtitles demuxers using this queue system.
int	ff_subtitles_queue_seek (FFDemuxSubtitlesQueue *q, AVFormatContext *s, int stream_index, int64_t min_ts, int64_t ts, int64_t max_ts, int flags)
	Update current_sub_idx to emulate a seek.
void	ff_subtitles_queue_clean (FFDemuxSubtitlesQueue *q)
	Remove and destroy all the subtitles packets.
int	ff_smil_extract_next_text_chunk (FFTextReader *tr, AVBPrint *buf, char *c)
	SMIL helper to load next chunk ("<...>" or untagged content) in buf.
const char *	ff_smil_get_attr_ptr (const char *s, const char *attr)
	SMIL helper to point on the value of an attribute in the given tag.
void	ff_subtitles_read_chunk (AVIOContext *pb, AVBPrint *buf)
	Same as ff_subtitles_read_text_chunk(), but read from an AVIOContext.
void	ff_subtitles_read_text_chunk (FFTextReader *tr, AVBPrint *buf)
	Read a subtitles chunk from FFTextReader.
static av_always_inline int	ff_subtitles_next_line (const char *ptr)
	Get the number of characters to increment to jump to the next line, or to the end of the string.
ptrdiff_t	ff_subtitles_read_line (FFTextReader *tr, char *buf, size_t size)
	Read a line of text.

Enumeration Type Documentation

enum sub_sort

Enumerator:

SUB_SORT_TS_POS	sort by timestamps, then position
SUB_SORT_POS_TS	sort by position, then timestamps

Definition at line 29 of file subtitles.h.

enum ff_utf_type

Enumerator:

FF_UTF_8
FF_UTF16LE
FF_UTF16BE

Definition at line 34 of file subtitles.h.

Function Documentation

void ff_text_init_avio	(	void *	s,
		FFTextReader *	r,
		AVIOContext *	pb
	)

Initialize the FFTextReader from the given AVIOContext.

This function will read some bytes from pb, and test for UTF-8 or UTF-16 BOMs. Further accesses to FFTextReader will read more data from pb. If s is not NULL, the user will be warned if a UTF-16 conversion takes place.

The purpose of FFTextReader is to transparently convert read data to UTF-8 if the stream had a UTF-16 BOM.

Parameters

s	Pointer to provide av_log context
r	object which will be initialized
pb	stream to read from (referenced as long as FFTextReader is in use)

Definition at line 27 of file subtitles.c.

Referenced by ass_read_header(), ff_text_init_buf(), realtext_read_header(), sami_read_header(), and srt_read_header().

void ff_text_init_buf	(	FFTextReader *	r,
		void *	buf,
		size_t	size
	)

Similar to ff_text_init_avio(), but sets it up to read from a bounded buffer.

Parameters

r	object which will be initialized
buf	buffer to read from (referenced as long as FFTextReader is in use)
size	size of buf

Definition at line 53 of file subtitles.c.

Referenced by ass_probe(), realtext_probe(), sami_probe(), and srt_probe().

int64_t ff_text_pos

(

FFTextReader *

r

)

Return the byte position of the next byte returned by ff_text_r8().

For UTF-16 source streams, this will return the original position, but it will be incorrect if a codepoint was only partially read with ff_text_r8().

Definition at line 60 of file subtitles.c.

Referenced by get_line(), realtext_read_header(), sami_read_header(), and srt_read_header().

int ff_text_r8

(

FFTextReader *

r

)

Return the next byte.

The return value is always 0 - 255. Returns 0 on EOF. If the source stream is UTF-16, this reads from the stream converted to UTF-8. On invalid UTF-16, 0 is returned.

Definition at line 65 of file subtitles.c.

Referenced by ff_smil_extract_next_text_chunk(), ff_subtitles_read_line(), ff_subtitles_read_text_chunk(), ff_text_peek_r8(), ff_text_read(), get_line(), and srt_probe().

int ff_text_eof

(

FFTextReader *

r

)

Return non-zero if EOF was reached.

Definition at line 92 of file subtitles.c.

Referenced by ff_subtitles_read_line(), realtext_read_header(), sami_read_header(), and srt_read_header().

int ff_text_peek_r8

(

FFTextReader *

r

)

Like ff_text_r8(), but don't remove the byte from the buffer.

Definition at line 97 of file subtitles.c.

Referenced by ff_subtitles_read_line(), and srt_probe().

void ff_text_read	(	FFTextReader *	r,
		char *	buf,
		size_t	size
	)

Read the given number of bytes (in UTF-8).

On error or EOF, \0 bytes are written.

Definition at line 86 of file subtitles.c.

Referenced by ass_probe(), realtext_probe(), and sami_probe().

AVPacket* ff_subtitles_queue_insert	(	FFDemuxSubtitlesQueue *	q,
		const uint8_t *	event,
		int	len,
		int	merge
	)

Insert a new subtitle event.

Parameters

event	the subtitle line, may not be zero terminated
len	the length of the event (in strlen() sense, so without '\0')
merge	set to 1 if the current event should be concatenated with the previous one instead of adding a new entry, 0 otherwise

Definition at line 111 of file subtitles.c.

Referenced by aqt_read_header(), ass_read_header(), jacosub_read_header(), lrc_read_header(), microdvd_read_header(), mpl2_read_header(), mpsub_read_header(), parse_file(), pjs_read_header(), realtext_read_header(), sami_read_header(), srt_read_header(), stl_read_header(), subviewer1_read_header(), subviewer_read_header(), vplayer_read_header(), and webvtt_read_header().

void ff_subtitles_queue_finalize

(

FFDemuxSubtitlesQueue *

q

)

Set missing durations and sort subtitles by PTS, and then byte position.

Definition at line 169 of file subtitles.c.

Referenced by aqt_read_header(), ass_read_header(), jacosub_read_header(), lrc_read_header(), microdvd_read_header(), mpl2_read_header(), mpsub_read_header(), pjs_read_header(), realtext_read_header(), sami_read_header(), srt_read_header(), stl_read_header(), subviewer1_read_header(), subviewer_read_header(), tedcaptions_read_header(), vplayer_read_header(), and webvtt_read_header().

int ff_subtitles_queue_read_packet	(	FFDemuxSubtitlesQueue *	q,
		AVPacket *	pkt
	)

Generic read_packet() callback for subtitles demuxers using this queue system.

Definition at line 181 of file subtitles.c.

Referenced by aqt_read_packet(), ass_read_packet(), jacosub_read_packet(), lrc_read_packet(), microdvd_read_packet(), mpl2_read_packet(), mpsub_read_packet(), pjs_read_packet(), realtext_read_packet(), sami_read_packet(), srt_read_packet(), stl_read_packet(), subviewer1_read_packet(), subviewer_read_packet(), tedcaptions_read_packet(), vplayer_read_packet(), and webvtt_read_packet().

int ff_subtitles_queue_seek	(	FFDemuxSubtitlesQueue *	q,
		AVFormatContext *	s,
		int	stream_index,
		int64_t	min_ts,
		int64_t	ts,
		int64_t	max_ts,
		int	flags
	)

Update current_sub_idx to emulate a seek.

Except the first parameter, it matches AVInputFormat->read_seek2 prototypes.

Definition at line 218 of file subtitles.c.

Referenced by aqt_read_seek(), ass_read_seek(), jacosub_read_seek(), lrc_read_seek(), microdvd_read_seek(), mpl2_read_seek(), mpsub_read_seek(), pjs_read_seek(), realtext_read_seek(), sami_read_seek(), srt_read_seek(), stl_read_seek(), subviewer1_read_seek(), subviewer_read_seek(), tedcaptions_read_seek(), vplayer_read_seek(), and webvtt_read_seek().

void ff_subtitles_queue_clean

(

FFDemuxSubtitlesQueue *

q

)

Remove and destroy all the subtitles packets.

Definition at line 270 of file subtitles.c.

Referenced by aqt_read_close(), ass_read_close(), jacosub_read_close(), lrc_read_close(), microdvd_read_close(), mpl2_read_close(), mpsub_read_close(), pjs_read_close(), realtext_read_close(), sami_read_close(), srt_read_close(), stl_read_close(), subviewer1_read_close(), subviewer_read_close(), tedcaptions_read_close(), tedcaptions_read_header(), vplayer_read_close(), and webvtt_read_close().

int ff_smil_extract_next_text_chunk	(	FFTextReader *	tr,
		AVBPrint *	buf,
		char *	c
	)

SMIL helper to load next chunk ("<...>" or untagged content) in buf.

Parameters

c	cached character, to avoid a backward seek

Definition at line 280 of file subtitles.c.

Referenced by realtext_read_header(), and sami_read_header().

const char* ff_smil_get_attr_ptr	(	const char *	s,
		const char *	attr
	)

SMIL helper to point on the value of an attribute in the given tag.

Parameters

s	SMIL tag ("<...>")
attr	the attribute to look for

Definition at line 303 of file subtitles.c.

Referenced by realtext_read_header(), and sami_read_header().

void ff_subtitles_read_chunk	(	AVIOContext *	pb,
		AVBPrint *	buf
	)

Same as ff_subtitles_read_text_chunk(), but read from an AVIOContext.

Definition at line 370 of file subtitles.c.

Referenced by mpsub_read_header(), and webvtt_read_header().

void ff_subtitles_read_text_chunk	(	FFTextReader *	tr,
		AVBPrint *	buf
	)

Read a subtitles chunk from FFTextReader.

A chunk is defined by a multiline "event", ending with a second line break. The trailing line breaks are trimmed. CRLF are supported. Example: "foo\r\nbar\r\n\r\nnext" will print "foo\r\nbar" into buf, and pb will focus on the 'n' of the "next" string.

Parameters

tr	I/O context
buf	an initialized buf where the chunk is written

Note

buf is cleared before writing into it.

Definition at line 328 of file subtitles.c.

Referenced by ff_subtitles_read_chunk(), and srt_read_header().

static av_always_inline int ff_subtitles_next_line ( const char *  ptr )

static

Get the number of characters to increment to jump to the next line, or to the end of the string.

The function handles the following line breaks schemes: LF, CRLF (MS), or standalone CR (old MacOS).

Definition at line 185 of file subtitles.h.

Referenced by get_pts(), jacosub_probe(), microdvd_probe(), mpl2_probe(), mpsub_probe(), and stl_probe().

ptrdiff_t ff_subtitles_read_line	(	FFTextReader *	tr,
		char *	buf,
		size_t	size
	)

Read a line of text.

Discards line ending characters. The function handles the following line breaks schemes: LF, CRLF (MS), or standalone CR (old MacOS).

Returns the number of bytes written to buf. Always writes a terminating 0, similar as with snprintf.

Note

returns a negative error code if a \0 byte is found

Definition at line 379 of file subtitles.c.

Referenced by srt_probe().