rational.c File Reference

---

Detailed Description

Rational numbers.

Author:

Michael Niedermayer <michaelni@gmx.at>

Definition in file rational.c.

Go to the source code of this file.

Functions
int	av_reduce (int *dst_nom, int *dst_den, int64_t nom, int64_t den, int64_t max)
	Reduce a fraction.
AVRational	av_mul_q (AVRational b, AVRational c)
	Multiplies two rationals.
AVRational	av_div_q (AVRational b, AVRational c)
	Divides one rational by another.
AVRational	av_add_q (AVRational b, AVRational c)
	Adds two rationals.
AVRational	av_sub_q (AVRational b, AVRational c)
	Subtracts one rational from another.
AVRational	av_d2q (double d, int max)
	Converts a double precision floating point number to a rational.

---

Function Documentation

int av_reduce	(	int *	dst_nom,
		int *	dst_den,
		int64_t	nom,
		int64_t	den,
		int64_t	max
	)

Reduce a fraction.

This is useful for framerate calculations.

Parameters:

	dst_nom	destination numerator
	dst_den	destination denominator
	nom	source numerator
	den	source denominator
	max	the maximum allowed for dst_nom & dst_den

Returns:

1 if exact, 0 otherwise

Definition at line 35 of file rational.c.

Referenced by asf_read_header(), av_add_q(), av_d2q(), av_find_stream_info(), av_mul_q(), avcodec_string(), MPEG2fixup::BuildFrame(), decode_slice_header(), dxa_read_header(), matroska_read_header(), mpeg_decode_postinit(), smacker_read_header(), vmd_read_header(), yuv4_generate_header(), and yuv4_read_header().

AVRational av_mul_q	(	AVRational	b,
		AVRational	c
	)

Multiplies two rationals.

Parameters:

	b	first rational.
	c	second rational.

Returns:

b*c.

Definition at line 77 of file rational.c.

Referenced by av_div_q(), and mkv_write_tracks().

AVRational av_div_q	(	AVRational	b,
		AVRational	c
	)

Divides one rational by another.

Parameters:

	b	first rational.
	c	second rational.

Returns:

b/c.

Definition at line 82 of file rational.c.

Referenced by mpeg_decode_postinit().

AVRational av_add_q	(	AVRational	b,
		AVRational	c
	)

Adds two rationals.

Parameters:

	b	first rational.
	c	second rational.

Returns:

b+c.

Definition at line 86 of file rational.c.

Referenced by av_sub_q().

AVRational av_sub_q	(	AVRational	b,
		AVRational	c
	)

Subtracts one rational from another.

Parameters:

	b	first rational.
	c	second rational.

Returns:

b-c.

Definition at line 91 of file rational.c.

AVRational av_d2q	(	double	d,
		int	max
	)

Converts a double precision floating point number to a rational.

Parameters:

	d	double to convert
	max	the maximum allowed numerator and denominator

Returns:

(AVRational) d.

Definition at line 95 of file rational.c.

Referenced by av_get_q(), av_opt_set_defaults2(), av_parse_video_frame_rate(), av_set_number(), mpeg_decode_postinit(), nuv_header(), and thp_read_header().