edge_common.h File Reference

#include "avfilter.h"

Go to the source code of this file.

Macros
#define	PROTO_SOBEL(depth)
	Simple sobel operator to get rounded gradients. More...
#define	PROTO_GAUSSIAN_BLUR(depth)
	Applies gaussian blur. More...

Enumerations
enum	AVRoundedDirection { DIRECTION_45UP, DIRECTION_45DOWN, DIRECTION_HORIZONTAL, DIRECTION_VERTICAL }
	Rounded directions used in av_image_sobel() More...

Functions
void	ff_non_maximum_suppression (int w, int h, uint8_t *dst, int dst_linesize, const int8_t *dir, int dir_linesize, const uint16_t *src, int src_linesize)
	Filters rounded gradients to drop all non-maxima pixels in the magnitude image Expects gradients generated by av_image_sobel() Expects zero's in the destination buffer dst. More...
void	ff_double_threshold (int low, int high, int w, int h, uint8_t *dst, int dst_linesize, const uint8_t *src, int src_linesize)
	Filters all pixels in src to keep all pixels > high, and keep all pixels > low where all surrounding pixels > high. More...

Detailed Description

common functions for edge detection

Definition in file edge_common.h.

Macro Definition Documentation

PROTO_SOBEL

#define PROTO_SOBEL

(

depth

)

Value:

void ff_sobel_##depth(int w, int h,                                          \
                      uint16_t *dst, int dst_linesize,                       \
                      int8_t *dir, int dir_linesize,                         \
                      const uint8_t *src, int src_linesize, int src_stride);

Simple sobel operator to get rounded gradients.

Parameters

w	the width of the image in pixels
h	the height of the image in pixels
dst	data pointers to magnitude image
dst_linesize	linesizes for the magnitude image
dir	data pointers to direction image
dir_linesize	linesizes for the direction image
src	data pointers to source image
src_linesize	linesizes for the source image

Definition at line 51 of file edge_common.h.

PROTO_GAUSSIAN_BLUR

#define PROTO_GAUSSIAN_BLUR

(

depth

)

Value:

void ff_gaussian_blur_##depth(int w, int h,                                          \
                              uint8_t *dst, int dst_linesize,                        \
                              const uint8_t *src, int src_linesize, int src_stride);

Applies gaussian blur.

5x5 kernels, sigma = 1.4

Parameters

w	the width of the image in pixels
h	the height of the image in pixels
dst	data pointers to destination image
dst_linesize	linesizes for the destination image
src	data pointers to source image
src_linesize	linesizes for the source image

Definition at line 107 of file edge_common.h.

Enumeration Type Documentation

AVRoundedDirection

enum AVRoundedDirection

Rounded directions used in av_image_sobel()

Enumerator
DIRECTION_45UP
DIRECTION_45DOWN
DIRECTION_HORIZONTAL
DIRECTION_VERTICAL

Definition at line 32 of file edge_common.h.

Function Documentation

ff_non_maximum_suppression()

void ff_non_maximum_suppression	(	int	w,
		int	h,
		uint8_t *	dst,
		int	dst_linesize,
		const int8_t *	dir,
		int	dir_linesize,
		const uint16_t *	src,
		int	src_linesize
	)

Filters rounded gradients to drop all non-maxima pixels in the magnitude image Expects gradients generated by av_image_sobel() Expects zero's in the destination buffer dst.

Parameters

w	the width of the image in pixels
h	the height of the image in pixels
dst	data pointers to magnitude image
dst_linesize	linesizes for the magnitude image
dir	data pointers to direction image
dir_linesize	linesizes for the direction image
src	data pointers to source image
src_linesize	linesizes for the source image

Definition at line 60 of file edge_common.c.

Referenced by blurdetect_filter_frame(), and filter_frame().

ff_double_threshold()

void ff_double_threshold	(	int	low,
		int	high,
		int	w,
		int	h,
		uint8_t *	dst,
		int	dst_linesize,
		const uint8_t *	src,
		int	src_linesize
	)

Filters all pixels in src to keep all pixels > high, and keep all pixels > low where all surrounding pixels > high.

Parameters

low	the low threshold value
high	the hegh threshold value
w	the width of the image in pixels
h	the height of the image in pixels
dst	data pointers to destination image
dst_linesize	linesizes for the destination image
src	data pointers to source image
src_linesize	linesizes for the source image

Definition at line 89 of file edge_common.c.

Referenced by blurdetect_filter_frame(), and filter_frame().