#include "libavutil/common.h"
#include "libavutil/avassert.h"
#include "transform.h"

Macros
#define	INTERPOLATE_METHOD(name)

#define	PIXEL(img, x, y, w, h, stride, def)

Functions
	INTERPOLATE_METHOD (interpolate_nearest)
	Nearest neighbor interpolation. More...

	INTERPOLATE_METHOD (interpolate_bilinear)
	Bilinear interpolation. More...

	INTERPOLATE_METHOD (interpolate_biquadratic)
	Biquadratic interpolation. More...

void	ff_get_matrix (float x_shift, float y_shift, float angle, float scale_x, float scale_y, float *matrix)
	Get an affine transformation matrix from given translation, rotation, and zoom factors. More...

int	ff_affine_transform (const uint8_t src, uint8_t dst, int src_stride, int dst_stride, int width, int height, const float *matrix, enum InterpolateMethod interpolate, enum FillMethod fill)
	Do an affine transformation with the given interpolation method. More...

Detailed Description

transform input video

Definition in file transform.c.

Macro Definition Documentation

◆ INTERPOLATE_METHOD

#define INTERPOLATE_METHOD ( name )

Value:

static uint8_t name(float x, float y, const uint8_t *src, \

int width, int height, int stride, uint8_t def)

Definition at line 32 of file transform.c.

◆ PIXEL

#define PIXEL	(	img,
		x,
		y,
		w,
		h,
		stride,
		def
	)

Value:

    ((x) < 0 || (y) < 0) ? (def) : \
    (((x) >= (w) || (y) >= (h)) ? (def) : \
    img[(x) + (y) * (stride)])

Definition at line 36 of file transform.c.

Function Documentation

◆ INTERPOLATE_METHOD() [1/3]

INTERPOLATE_METHOD ( interpolate_nearest )

Nearest neighbor interpolation.

Definition at line 44 of file transform.c.

◆ INTERPOLATE_METHOD() [2/3]

INTERPOLATE_METHOD ( interpolate_bilinear )

Bilinear interpolation.

Definition at line 52 of file transform.c.

◆ INTERPOLATE_METHOD() [3/3]

INTERPOLATE_METHOD ( interpolate_biquadratic )

Biquadratic interpolation.

Definition at line 79 of file transform.c.

◆ ff_get_matrix()

void ff_get_matrix	(	float	x_shift,
		float	y_shift,
		float	angle,
		float	scale_x,
		float	scale_y,
		float *	matrix
	)

Get an affine transformation matrix from given translation, rotation, and zoom factors.

The matrix will look like:

[ scale_x * cos(angle), -sin(angle), x_shift, sin(angle), scale_y * cos(angle), y_shift, 0, 0, 1 ]

Parameters

x_shift	horizontal translation
y_shift	vertical translation
angle	rotation in radians
scale_x	x scale percent (1.0 = 100%)
scale_y	y scale percent (1.0 = 100%)
matrix	9-item affine transformation matrix

Definition at line 106 of file transform.c.

Referenced by filter_frame(), and transform_center_scale().

◆ ff_affine_transform()

int ff_affine_transform	(	const uint8_t *	src,
		uint8_t *	dst,
		int	src_stride,
		int	dst_stride,
		int	width,
		int	height,
		const float *	matrix,
		enum InterpolateMethod	interpolate,
		enum FillMethod	fill
	)

Do an affine transformation with the given interpolation method.

This multiplies each vector [x,y,1] by the matrix and then interpolates to get the final value.