EP0644696A2
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EP
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Method for temporal filtering of video signals using a motion adaptive spatial filter
Assignee: WiniaDaewoo Co Ltd
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Filing: 1994-09-16
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Granted: —
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Expires: 2014-09-16
Abstract
Abstract A motion adaptive spatial filtering method is employed as a prefilter in an image coding apparatus, which processes the temporal band-limitation of a video signal without temporal aliasing by using a spatial filter having a band-limitation characteristic according to a desired temporal cutoff frequency. <IMAGE>
Inventors
- 👤 Jong-Hoon Kim
- 👤 Seong-Dae Prof. Dept. of Elec.Eng. KAIST Kim
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-09 14:58
CPC Classifications
H; H04; H04N; H04N19/00; H04N19/50; H04N19/80; H04N5/00; H04N5/14; H04N5/21
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
115 words
A method for filtering a video signal having a plurality of pixels with a predetermined temporal cutoff frequency to achieve a temporal band-limitation thereof, comprising the steps of: (a1) determining a motion vector which represents the motion for a current pixel; (a2) calculating a spatial filter impulse response in the frequency domain based on the determined motion vector and the temporal cutoff frequency; (a3) determining an impulse response in the spatial domain based on the spatial filter impulse response in the frequency domain, thereby performing a filtering operation for the current pixel in the video signal; and (a4) repeating said steps (a1) to (a3) until all of the pixels in the video signal are processed.
Claim 2
Independent Claim
142 words
A method for filtering a video signal having a plurality of pixels with a predetermined temporal cutoff frequency to achieve a temporal band-limitation thereof, comprising the steps of: (b1) calculating a plurality of spatial filter impulse responses in the frequency domain based on a plurality of predetermined candidate motion vectors and the temporal cutoff frequency; (b2) determining a plurality of impulse responses in the spatial domain based on the spatial filter impulse responses in the frequency domain; (b3) determining one of said candidate motion vectors as a motion vector which represents the motion for a current pixel; (b4) selecting one of said impulse responses based on the determined motion vector, thereby performing a filtering operation for the current pixel in the video signal; and (b5) repeating said steps (b3) to (b4) until all of the pixels in the video signal are processed.
Claim 3
Dependent Claim
134 words
The method of claim 1 or 2, wherein the filtered video signal g(l, m, n) is represented as follows: wherein l and m represent the position of a pixel in the video signal; n is a frame number; the impulse response h s (k1, k2) are determined by inverse Fourier transforming the spatial filter impulse response H s (f x , f y ) in the frequency domain which is defined as wherein v x and v y denote a motion vector for a corresponding pixel and f t c denotes the temporal cutoff frequency; k1 and k2 are indexes for the 2-dimensional filter h s (·) whose absolute values are not greater that L and M, respectively; positive integers L and M represent the respective lengths of a 2-dimensional filter h s (·).
References Cited (Backward Citations)
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