{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

08_ffilterx

# 08_ffilterx - H u v a ﬁlter transfer function g x y = f x...

This preview shows pages 1–8. Sign up to view the full content.

Frequency-Domain Filters COMP344 COMP344 Frequency-Domain Filters

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
Filtering in Frequency Domain One image, two representations f ( x , y ): spatial (a collection of pixels) F ( u , v ): frequency (rate of change of intensity values or grey level) COMP344 Frequency-Domain Filters
Continuous Convolution Convolution of f and g : ( f * g )( t ) = R b a f ( τ ) g ( t - τ ) d τ often a = -∞ and b = + ( demo1 ) ( demo1 ) COMP344 Frequency-Domain Filters

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
Discrete Convolution ( f * g )( t ) = R b a f ( τ ) g ( t - τ ) d τ Discrete convolution : ( f * g )( m ) = N n =1 f ( n ) g ( m - n ) ( demo ) COMP344 Frequency-Domain Filters
Convolution Theorem f ( x , y ) * h ( x , y ) F ( u , v ) H ( u , v ) the Fourier transform of a convolution is the product of the Fourier transforms COMP344 Frequency-Domain Filters

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
Filtering in Frequency Domain

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: H ( u , v ): a ﬁlter transfer function g ( x , y ) = f ( x , y ) * h ( x , y ) G ( u , v ) = H ( u , v ) F ( u , v ) (element-by-element multiplication) g ( x , y ) = F-1 { G ( u , v ) } COMP344 Frequency-Domain Filters Example: Lowpass Filter Reduce the high-frequency content – blurring or smoothing COMP344 Frequency-Domain Filters Example: Highpass Filter Increase the magnitude of high-frequency components relative to low-frequency components – sharpening COMP344 Frequency-Domain Filters...
View Full Document

{[ snackBarMessage ]}

### Page1 / 8

08_ffilterx - H u v a ﬁlter transfer function g x y = f x...

This preview shows document pages 1 - 8. Sign up to view the full document.

View Full Document
Ask a homework question - tutors are online