Writing text

Encode text. More...

Functions
int	lqt_add_text_track (quicktime_t *file, int timescale)
	Add a text track. More...
void	lqt_set_text_language (quicktime_t *file, int track, const char *language)
	Set the language for a text track. More...
void	lqt_set_chapter_track (quicktime_t *file, int track)
	Make a text track a chapter track. More...
void	lqt_set_text_box (quicktime_t *file, int track, uint16_t top, uint16_t left, uint16_t bottom, uint16_t right)
	Set the text box of a text track. More...
void	lqt_set_text_fg_color (quicktime_t *file, int track, uint16_t r, uint16_t g, uint16_t b, uint16_t a)
	Set the foreground color of a text track. More...
void	lqt_set_text_bg_color (quicktime_t *file, int track, uint16_t r, uint16_t g, uint16_t b, uint16_t a)
	Set the background color of a text track. More...
int	lqt_write_text (quicktime_t *file, int track, const char *text, int64_t duration)
	Write a text sample. More...
void	lqt_set_text_pts_offset (quicktime_t *file, int track, int64_t offset)
	Set an video pts offset. More...

Detailed Description

Encode text.

Function Documentation

int lqt_add_text_track	(	quicktime_t *	file,
		int	timescale
	)

Add a text track.

Parameters

file	A quicktime handle
timescale	The timescale, in which timestamps will be given.

void lqt_set_text_language	(	quicktime_t *	file,
		int	track,
		const char *	language
	)

Set the language for a text track.

Parameters

file	A quicktime handle
track	Track index (starting with 0)
language	ISO-639 Language code

The language code is a 3-character code, English is "eng", Japanese is "jpn".

void lqt_set_chapter_track	(	quicktime_t *	file,
		int	track
	)

Make a text track a chapter track.

Parameters

file	A quicktime handle
track	Track index (starting with 0)

By default, text tracks are subtitles. By calling this function, you tell libquicktime, that the text track should be a chapter track.

void lqt_set_text_box	(	quicktime_t *	file,
		int	track,
		uint16_t	top,
		uint16_t	left,
		uint16_t	bottom,
		uint16_t	right
	)

Set the text box of a text track.

Parameters

file	A quicktime handle
track	Track index (starting with 0)
top	Top border
left	Left border
bottom	Bottom border
right	Right border

void lqt_set_text_fg_color	(	quicktime_t *	file,
		int	track,
		uint16_t	r,
		uint16_t	g,
		uint16_t	b,
		uint16_t	a
	)

Set the foreground color of a text track.

Parameters

file	A quicktime handle
track	Track index (starting with 0)
r	Red
g	Green
b	Blue
a	Alpha

Color values are between 0x0000 and 0xffff. The alpha value is only used for mp4.

void lqt_set_text_bg_color	(	quicktime_t *	file,
		int	track,
		uint16_t	r,
		uint16_t	g,
		uint16_t	b,
		uint16_t	a
	)

Set the background color of a text track.

Parameters

file	A quicktime handle
track	Track index (starting with 0)
r	Red
g	Green
b	Blue
a	Alpha

Color values are between 0x0000 and 0xffff. The alpha value is only used for mp4. For Quicktime, the text box is set to transparent if the alpha value is below 0x8000.

int lqt_write_text	(	quicktime_t *	file,
		int	track,
		const char *	text,
		int64_t	duration
	)

Write a text sample.

Parameters

file	A quicktime handle
track	Track index (starting with 0)
text	A null-terminated UTF-8 string
duration	The duration associated with this sample

Returns

0 if a the text sample could be written to the file, nonzero else

void lqt_set_text_pts_offset	(	quicktime_t *	file,
		int	track,
		int64_t	offset
	)

Set an video pts offset.

Parameters

file	A quicktime handle
track	Track index (starting with 0)
offset	PTS offset of the subtitles (in timescale units)