Mumbai University > Electronics and telecommunication > Sem 7 > image and video processing

Marks: 05

Years: MAY 2016

The various Edge detection masks are:-

I. Roberts Mask

II. Prewitts Mask

III. Sobel Mask

I. Roberts Mask

i. Following is the Roberts Mask

$|∇ F | = |Z_5 – Z_9| + |Z_6 – Z_8|$

The values of the Roberts Mask are:

and

The values of the two Roberts Mask are:

II. Prewitts Mask

$∇ F =$ x- gradient + y-gradient

i.e.$ ∇ F = |(Z_7 + Z_8 + Z_9 ) – (Z_1 + Z_2 + Z_3)| + |(Z_3 + Z_6 + Z_9 ) – (Z_1 + Z_4 + Z_7)|$

Thus from this equation we get the Prewitts mask as:

III. Sobels Mask

∇ F = x- gradient + y-gradient

i.e. $∇ F = |(Z_7 + 2Z_8 + Z_9 ) – (Z_1 + 2Z_2 + Z_3)| + |(Z_3 + 2Z_6 + Z_9 ) – (Z_1 + 2Z_4 + Z_7)|$

From this equation, the sobels mask is as follows