IMAGES• There are two types of images• Vector Images• Digital Images
VECTOR IMAGES• Vector images made up of vectors which lead through locations called control points.• Each of these control points has define on the X and Y axes of the work plain.
DIGITAL IMAGES• A digital image is an 2 dim-array of real numbers.• 2-D image is divided into N-rows and M-columns.• The intersection of these rows & columns is known as pixels Origin x f(x,y) y
TYPES OF DIGITAL IMAGES• Binary Images (Black and White Images)• Gray scale Images• Color Images
BINARY IMAGES• Each pixel is just Black or White.• There is only two possible values for each pixel i.e. 0 or 1.
GRAY SCALE IMAGE• Each pixel value of gray scale images normally from 0 (Black) to 255 (White)
COLOR IMAGES• In color images each pixel has particular color; that color being described by the amount of red, blue and green in it.• Each of these components has a range 0-255.
HISTOGRAM• Histogram of image describe the intensity value of pixels that occur in an image.
IMAGE NOISE• Noise, in image, is any degradation in an image signal, caused by external disturbance while an image is being sent from one place to another place via Satellite, Wireless, and Network cable.
SOURCE OF IMAGE NOISE• Error occurs in image signal while an image is being sent electronically from one place to another.• Sensor heat while clicking an image.• ISO factor: ISO number indicates how quickly a camera’s sensor absorbs light, higher ISO used, mare chance of noticeable noise.• Size of the sensor.
TYPES OF IMAGE NOISE• Salt and Pepper Noise• Gaussian Noise• Speckle Noise• Periodic Noise
SALT AND PEPPER NOISE• Its also known as Impulse Noise. This noise can be caused by sharp & sudden disturbances in the image signal.• Its appearance is randomly scattered white or black (or both) pixel over the image.
GAUSSIAN NOISE• Gaussian Noise is caused by random fluctuations in the signal. its modeled by random values added to an image.
SPECKLE NOISE• Speckle noise can be modeled by random values multiplied by pixel values of an image.
PERIODIC NOISE• Periodic noise is appearance when signal is subject to a periodic, rather than a random disturbance.
NEIGHBORS OF PIXEL• In a 3X3 region a pixel p at coordinate (i,j) has 2 horizontal and vertical neighbor whose coordinates are given in the figure:
SALT AND PEPPER NOISE REMOVAL• Minimum Filtering• Maximum Filtering• Mean Filtering• Rank Order Filtering• Median Filtering• New Generated Filtering
MINIMUM FILTERING• Current pixel replace by minimum pixel value of its neighboring pixels.
MAXIMUM FILTERING• Current pixel replace by maximum pixel value of its neighboring pixels.
MEAN FILTERING• Current pixel replace by arithmetic mean of its neighboring pixels values.
RANK ORDER FILTERING• Current pixel replace by user define order of its neighboring pixels.
MEDIAN FILTERING• Current pixel replace by mid element of its neighboring pixels.
NEW GENERATED FILTERINGCurrent pixel replace by arithmetic meanmid-1,mid,m+1of its neighboring pixels.