Astronomical Image Processing

molassesitalianAI and Robotics

Nov 6, 2013 (3 years and 11 months ago)

87 views

Astronomical Image Processing

with

Visual Fortran







Outline


Visual Fortran Graphic Control



Histogram Equalization


Pseudocolouring


Sobel

Edge Detector


Laplacian

Edge Detector


Hough Transform



Visual Fortran Graphic Control


32
-
bit RGB color value


SETCOLORRGB


SETBKCOLORRGB


SETPIXELCOLOR


SETPIXELSCOLOR



Visual Fortran Graphic Control


LOADIMAGE


SAVEIMAGE


INTEGERTORGB


RGBTOINTEGER

Image Enhancing Techniques


IMSL 2D Fourier Transform


Histogram Equalization


Gray scale


Full color


RGBTOHSI


HSITORGB

7.1 Visual Fortran
Graphic Control

32
-
bit RGB color value


alpha channel


binary 1111111 = hex FF


#0000FF


full
-
intensity red,


#00FF00


full
-
intensity green,


#FF0000



full
-
intensity blue,


#FFFFFF




setcolorRGB

setcolorRGB.F90

setBKcolorRGB

setBKcolorRGB.F90

SETPIXELCOLOR

SETPIXELCOLOR.F90

SETPIXELSCOLOR

SETPIXELSCOLOR.F90

7.1.2 Image2010


Image2010



LOADIMAGE




result = SAVEIMAGE (
filename
,
ulxcoord
,
ulycoord
,
lrxcoord
,
lrycoord
)


Put
LOADIMAGE and
SAVEIMAGE
together

Image2010



CALL INTEGERTORGB (
rgb
, red,
green, blue)


result = RGBTOINTEGER (red,
green, blue)


Put
INTEGERTORGB and
RGBTOINTEGER

together


Image2010



Histogram
Equalization


Pseudocolouring

7.2
Histogram Equalization

7.3 Edge Detection
Algoritms

7.3.1
Prewittt

Masks

7.3.2
Sobel

Edge Detector

Extreme and zero crossing

7.3.3
Laplacian

Edge Detector

3 x 3 mask for 4
-
neighborhoods and 8
-
neighborhood


7.3.4
Hough Transform


Generalized Hough transform


Classical Hough transform


features specified in some
parametric forms


tolerant of gaps


relatively unaffected by image
noise

Straight line searching



An N
3

operation!



Representation in parameter space


y = ax +b



Polar representation



y = ax +b



xcosθ + ysinθ = r


Applications


Driver drowsiness

2D Fourier Forward Transform

Backward (Inverse) Transform

4.2 2D Fourier Transform

High/Low pass Filter


The End

Next: sequential and parallel
laplace solvers