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gpiv-imgproc.h File Reference

module for image processing More...

Go to the source code of this file.

Data Structures
struct	__GpivImageProcPar
	Image processing parameters. More...
Defines
#define	GPIV_IMGPROCPAR_MAX__THRESHOLD   255
#define	GPIV_IMGPROCPAR_MAX__WINDOW   50
#define	GPIV_IMGPROCPAR_KEY   "IMGPROC"
Typedefs
typedef __GpivImageProcPar	GpivImageProcPar
Enumerations
enum	GpivImgFilter {   GPIV_IMGFI_MKTESTIMG, GPIV_IMGFI_SUBACK, GPIV_IMGFI_SMOOTH, GPIV_IMGFI_HILO, GPIV_IMGFI_CLIP, GPIV_IMGFI_FFT, GPIV_IMGFI_INVFFT, GPIV_IMGFI_CORR, GPIV_IMGFI_CONV, GPIV_IMGFI_LOWPASS,   GPIV_IMGFI_HIGHPASS, GPIV_IMGFI_GETBIT }
enum	GpivImgSmoothOperator { GPIV_IMGOP_EQUAL, GPIV_IMGOP_SUBTRACT, GPIV_IMGOP_ADD, GPIV_IMGOP_MULTIPLY, GPIV_IMGOP_DIVIDE }
Functions
void	gpiv_imgproc_default_parameters (GpivImageProcPar *imgproc_par_default, const gboolean force)
void	gpiv_imgproc_read_parameters (FILE *fp_h, GpivImageProcPar *image_proc_par, const gboolean print_par)
gchar *	gpiv_imgproc_check_parameters_read (GpivImageProcPar *image_proc_par, const GpivImageProcPar *image_proc_par_default)
gchar *	gpiv_imgproc_test_parameters (const GpivImageProcPar *image_proc_par)
void	gpiv_imgproc_print_parameters (FILE *fp, const GpivImageProcPar *image_proc_par)
GpivImageProcPar *	gpiv_imgproc_cp_parameters (const GpivImageProcPar *imgproc_par)
GpivImage *	gpiv_imgproc_mktestimg (const GpivImagePar *image_par, const GpivImageProcPar *image_proc_par)
gchar *	gpiv_imgproc_subtractimg (const GpivImage *image_in, GpivImage *image_out)
gchar *	gpiv_imgproc_smooth (GpivImage *image, const GpivImageProcPar *image_proc_par)
gchar *	gpiv_imgproc_highpass (GpivImage *image, const GpivImageProcPar *image_proc_par)
gchar *	gpiv_imgproc_highlow (GpivImage *image, const GpivImageProcPar *image_proc_par)
gchar *	gpiv_imgproc_clip (GpivImage *image, const GpivImageProcPar *image_proc_par)
gchar *	gpiv_imgproc_getbit (GpivImage *image, const GpivImageProcPar *image_proc_par)
gchar *	gpiv_imgproc_fft (GpivImage *image, const GpivImageProcPar *image_proc_par)
gchar *	gpiv_imgproc_lowpass (GpivImagePar image_par, GpivImageProcPar image_proc_par, guint16 **img)
gchar *	gpiv_imgproc_correlate (GpivImagePar image_par, GpivImageProcPar image_proc_par, guint16 **img1_in, guint16 **img2_in, guint16 ***img_out)
gchar *	gpiv_imgproc_convolve (GpivImagePar image_par, GpivImageProcPar image_proc_par, guint16 **img1_in, guint16 **img2_in, guint16 ***img_out)
gchar *	gpiv_imgproc_deform (GpivImage *image, const GpivPivData *piv_data)

---

Detailed Description

module for image processing

SOURCE: lib/imgproc.c

LAST MODIFICATION DATE:

Id

imgproc.h,v 1.6 2007-06-06 16:59:02 gerber Exp

Definition in file gpiv-imgproc.h.

---

Define Documentation

#define GPIV_IMGPROCPAR_KEY   "IMGPROC"

Key of image processing parameters

Definition at line 69 of file gpiv-imgproc.h.

#define GPIV_IMGPROCPAR_MAX__THRESHOLD   255

Definition at line 66 of file gpiv-imgproc.h.

#define GPIV_IMGPROCPAR_MAX__WINDOW   50

Definition at line 67 of file gpiv-imgproc.h.

---

Typedef Documentation

typedef struct __GpivImageProcPar GpivImageProcPar

Definition at line 103 of file gpiv-imgproc.h.

---

Enumeration Type Documentation

enum GpivImgFilter

Image filter type

Enumerator:

GPIV_IMGFI_MKTESTIMG	Generate test image
GPIV_IMGFI_SUBACK	Subtract background image
GPIV_IMGFI_SMOOTH	Smooth filter
GPIV_IMGFI_HILO	High-low filter
GPIV_IMGFI_CLIP	Clipping
GPIV_IMGFI_FFT	FFT image
GPIV_IMGFI_INVFFT	Inverse FFT image
GPIV_IMGFI_CORR	Correlate
GPIV_IMGFI_CONV	Convolve
GPIV_IMGFI_LOWPASS	Low pass filter
GPIV_IMGFI_HIGHPASS	High pass filter
GPIV_IMGFI_GETBIT	Pointer operation to get the N least significant bits

Definition at line 74 of file gpiv-imgproc.h.

enum GpivImgSmoothOperator

Operator type when smoothing is performed

Enumerator:

GPIV_IMGOP_EQUAL	No action
GPIV_IMGOP_SUBTRACT	Subtract avarage
GPIV_IMGOP_ADD	Add avarage
GPIV_IMGOP_MULTIPLY	Multiply with avarage
GPIV_IMGOP_DIVIDE	Divide by avarage

Definition at line 94 of file gpiv-imgproc.h.

---

Function Documentation

gchar* gpiv_imgproc_check_parameters_read	(	GpivImageProcPar *	image_proc_par,
		const GpivImageProcPar *	image_proc_par_default
	)

Checks if all necessary image processing parameters have been read. Else they will be set to defaults.

Parameters:

[in]	image_proc_par_default	image processing parameters containing default values
[out]	image_proc_par	structure of image processing parameters

Returns:

NULL on success or error message on failure

gchar* gpiv_imgproc_clip	(	GpivImage *	image,
		const GpivImageProcPar *	image_proc_par
	)

Sets all pixel values lower than threshold to zero

Parameters:

[in]	image	image to be clipped in-place.
[in]	image_proc_par	structure of image processing parameters

Returns:

NULL on success or error message on failure

gchar* gpiv_imgproc_convolve	(	GpivImagePar	image_par,
		GpivImageProcPar	image_proc_par,
		guint16 **	img1_in,
		guint16 **	img2_in,
		guint16 ***	img_out
	)

Convolves two images

Parameters:

[in]	image_par	structure of image parameters
[in]	image_proc_par	structure of image processing parameters
[in]	img1_in	first input image. Needs to be allocated
[in]	img2_in	second input image. Needs to be allocated
[out]	img_out	pointer to output image. Not necessarily allocated

Returns:

NULL on success or error message on failure

gchar* gpiv_imgproc_correlate	(	GpivImagePar	image_par,
		GpivImageProcPar	image_proc_par,
		guint16 **	img1_in,
		guint16 **	img2_in,
		guint16 ***	img_out
	)

Correlates two images

Parameters:

[in]	image_par	structure of image parameters
[in]	image_proc_par	structure of image processing parameters
[in]	img1_in	first input image. Needs to be allocated
[in]	img2_in	second input image. Needs to be allocated
[out]	img_out	pointer to output image. Not necessarily allocated

Returns:

NULL on success or error message on failure

GpivImageProcPar* gpiv_imgproc_cp_parameters

(

const GpivImageProcPar *

imgproc_par

)

Copies image processing parameters.

Parameters:

[in]

imgproc_par

image processing parameters to be copied

Returns:

GpivImageProcPar or NULL on failure

void gpiv_imgproc_default_parameters	(	GpivImageProcPar *	imgproc_par_default,
		const gboolean	force
	)

Sets default parameter values

Parameters:

[in]	force	flag to enforce parameters set to defaults
[out]	imgproc_par_default	structure of image processing parameters

Returns:

void

gchar* gpiv_imgproc_deform	(	GpivImage *	image,
		const GpivPivData *	piv_data
	)

Image shifting and deformation routine for a single exposed, double frame PIV image pair with magnitude of PIV estimations at each pixel. Deforms first frame halfway forward and second frame halfway backward.

Parameters:

[in]	piv_data	PIV data
[in]	image	input image to be deformed in-place. Needs to be allocated

Returns:

NULL on success or error message on failure

gchar* gpiv_imgproc_fft	(	GpivImage *	image,
		const GpivImageProcPar *	image_proc_par
	)

Fast Fourier Transformation of image

Parameters:

[in]	image	input image to be modified in-place.
[in]	image_proc_par	structure of image processing parameters

Returns:

NULL on success or error message on failure

gchar* gpiv_imgproc_getbit	(	GpivImage *	image,
		const GpivImageProcPar *	image_proc_par
	)

Pointer operation to get the N least significant bits and moves them to most the significant bits

Parameters:

[in]	image	image to be filtered in-place
[in]	image_proc_par	structure of image processing parameters

Returns:

NULL on success or error message on failure

gchar* gpiv_imgproc_highlow	(	GpivImage *	image,
		const GpivImageProcPar *	image_proc_par
	)

High-low filter to maximize contrast by stretching pixel values to local max and min within window x window area

Parameters:

[in]	image	image to be filtered in-place
[in]	image_proc_par	structure of image processing parameters

Returns:

NULL on success or error message on failure

gchar* gpiv_imgproc_highpass	(	GpivImage *	image,
		const GpivImageProcPar *	image_proc_par
	)

Highpass filter on an image passing data from M - window,..,M/2, N - window,..,N/2

Parameters:

[in]	image	image to be be high-passed in-place
[in]	image_proc_par	structure of image processing parameters

Returns:

NULL on success or error message on failure

gchar* gpiv_imgproc_lowpass	(	GpivImagePar	image_par,
		GpivImageProcPar	image_proc_par,
		guint16 **	img
	)

Lowpass filter on an image

Parameters:

[in]	image_par	structure of image parameters
[in]	image_proc_par	structure of image processing parameters
[in]	img	input image to be filtered in-place. Needs to be allocated

Returns:

NULL on success or error message on failure

GpivImage* gpiv_imgproc_mktestimg	(	const GpivImagePar *	image_par,
		const GpivImageProcPar *	image_proc_par
	)

Genarates test image for image processing

Parameters:

[in]	image_par	structure of image parameters
[in]	image_proc_par	structure of image processing parameters

Returns:

GpivImage or NULL on failure

void gpiv_imgproc_print_parameters	(	FILE *	fp,
		const GpivImageProcPar *	image_proc_par
	)

Prints image processing parameters to file.

Parameters:

[in]	fp	file pointer to which paraeters will be printed. If NULL, stdout will be used
[in]	image_proc_par	structure of image processing parameters

Returns:

void

void gpiv_imgproc_read_parameters	(	FILE *	fp_h,
		GpivImageProcPar *	image_proc_par,
		const gboolean	print_par
	)

Reads image processing parameters

Parameters:

[in]	fp_h	file to be read
[in]	image_proc_par	pointer to structure of image processing parameters
[in]	print_par	prints parameters to stdout during reading
[out]	image_proc_par	pointer to structure of image processing parameters

Returns:

void

gchar* gpiv_imgproc_smooth	(	GpivImage *	image,
		const GpivImageProcPar *	image_proc_par
	)

Smoothing filter by taking mean value of surrounding window x window pixels

Parameters:

[in]	image	image to be smoothed in-place
[in]	image_proc_par	structure of image processing parameters

Returns:

NULL on success or error message on failure

gchar* gpiv_imgproc_subtractimg	(	const GpivImage *	image_in,
		GpivImage *	image_out
	)

Subtracts image intensities of img_in from img_out. To avoid swapping of intensities, output values are set to zero if img_in is larger than img_out. Images will have to be of identic dimensions.

Parameters:

[in]	image_in	image containing the intensities to be subtracted
[out]	image_out	modified image. will have to exist and allocated

Returns:

NULL on success or error message on failure

gchar* gpiv_imgproc_test_parameters

(

const GpivImageProcPar *

image_proc_par

)

Tests image processing parameters on validity.

Parameters:

[in]

image_proc_par

structure of image processing parameters

Returns:

NULL on success or error message on failure

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