US5409007A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Filter to reduce speckle artifact in ultrasound imaging
Assignee: General Electric Co
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Filing: 1993-11-26
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Granted: 1995-04-25
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Expires: 2013-11-26
Abstract
Abstract A method for reducing speckle artifact in an ultrasound image using a two-dimensional median filter having a diamond-shaped five-point kernel. The entire pixel image data is passed through the filter in a manner such that the center point of the kernel is effectively stepped down each range vector in sequence. The magnitudes of the pixel data at each of the five points in the kernel are compared and the value which has the middle magnitude is adopted as a new pixel value, which is substituted for the old pixel value at the center point. After a new filtered vector has been formed from the new pixel values produced at successive center points by stepping down one acoustic vector, the kernel is shifted by one vector and stepped down range again. This process continues through the entire set of vectors until a new set of filtered vectors is formed. This filter will remove speckle holes on the order of one pixel in size while preserving good edge definition.
Inventors
- 👤 Rowland F. Saunders
- 👤 Christopher J. Gilling
- 👤 James S. Lehouillier
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 20:37
CPC Classifications
G; G01; G01S; G01S7/00; G01S7/52; G01S7/52017; G01S7/52023; G01S7/52025; G01S7/52026; G01S7/52028; G01S15/00; G01S15/88; G01S15/89; G01S15/8906; G01S15/8979; G01S7/52077
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
158 words
An ultrasound imaging system comprising: a plurality of ultrasonic transducer elements for transmitting ultrasound beams along first, second and third paths of propagation through an object in a transmission mode; vector acquiring means for acquiring first, second and third vectors of image data, said image data of said first through third vectors being derived from the reflection by said object and the reception by said ultrasound transducer elements in a reception mode of portions of said ultrasound beams transmitted along said first through third paths of propagation respectively, each of said first through third vectors including at least first, second and third values acquired at first, second and third ranges respectively; median filtering means for substituting the middle value amongst said second values of said first and third vectors and said first through third values of said second vector for said second value of said second vector; and means for displaying image data which includes said middle value.
Claim 2
Dependent Claim
158 words
An ultrasound imaging system comprising: a plurality of ultrasonic transducer elements for transmitting ultrasound beams along first, second and third paths of propagation through an object in a transmission mode; vector acquiring means for acquiring first, second and third vectors of image data, said image data of said first through third vectors being derived from the reflection by said object and the reception by said ultrasound transducer elements in a reception mode of portions of said ultrasound beams transmitted along said first through third paths of propagation respectively, each of said first through third vectors including at least first, second and third values acquired at first, second and third ranges respectively; median filtering means for substituting the middle value amongst said second values of said first and third vectors and said first through third values of said second vector for said second value of said second vector; and means for displaying image data which includes said middle value.
Claim 3
Dependent Claim
62 words
The ultrasound imaging system as defined in claim 1, wherein said median filtering means comprises first through third shift registers, said first shift register storing said second value of said first vector, said second shift register storing said first through third values of said second vector, and said third shift register storing said second value of said third vector during a cycle.
Claim 4
Dependent Claim
44 words
The ultrasound imaging system as defined in claim 2, wherein said median filtering means further comprises a plurality of comparators for comparing said second values of said first and third vectors and said first through third values of said second vector with each other.
Claim 5
Dependent Claim
80 words
The ultrasound imaging system as defined in claim 3, wherein said median filtering means further comprises median combinational logic coupled to receive outputs from each of said comparators, and multiplexing means coupled to said first through third shift registers and to said median combinational logic for latching the middle value amongst said second values of said first and third vectors and said first through third values of said second vector in response to control signals from said median combinational logic.
Claim 6
Dependent Claim
46 words
The ultrasound imaging system as defined in claim 2, wherein said vector acquiring means comprises a latch, a FIFO and a shifter connected in series, said shifter having first through third 8-bit ports connected to said first through third shift registers of said median filtering means.
Claim 7
Dependent Claim
25 words
The ultrasound imaging system as defined in claim 1, wherein said vector acquiring means comprises a latch, a FIFO and a shifter connected in series.
Claim 8
Dependent Claim
28 words
The ultrasound imaging system as defined in claim 1, wherein said vector acquiring means comprises a latch, a FIFO, a shifter and a threshold offset connected in series.
Claim 9
Dependent Claim
38 words
The ultrasound imaging system as defined in claim 1, further comprising scan conversion means for generating addresses used to map the output of said median filtering means into a pixel value at a given X-Y coordinate for display.
Claim 10
Dependent Claim
17 words
The ultrasound imaging system as defined in claim 1, wherein said image data comprises ultrasound amplitude data.
Claim 11
Dependent Claim
18 words
The ultrasound imaging system as defined in claim 1, wherein said image data comprises ultrasound Doppler shift data.
Claim 12
Independent Claim
183 words
A method for reducing speckle artifact in an ultrasound image, comprising the steps of: transmitting ultrasound beams along first, second and third paths of propagation through an object by activation of a plurality of ultrasonic transducer elements in a transmission mode; acquiring first, second and third vectors of image data, said image data of said first through third vectors being derived from the reflection by said object and the reception by said ultrasound transducer elements in a reception mode of portions of said ultrasound beams transmitted along said first through third paths of propagation respectively, each of said first through third vectors including at least first, second and third values acquired at first, second and third ranges respectively; selecting said second values of said first and third vectors and said first through third values of said second vector; determining the middle value amongst said second values of said first and third vectors and said first through third values of said second vector; substituting said middle value for said second value of said second vector; and displaying image data which includes said middle value.
Claim 13
Independent Claim
183 words
A method for reducing speckle artifact in an ultrasound image, comprising the steps of: transmitting ultrasound beams along first, second and third paths of propagation through an object by activation of a plurality of ultrasonic transducer elements in a transmission mode; acquiring first, second and third vectors of image data, said image data of said first through third vectors being derived from the reflection by said object and the reception by said ultrasound transducer elements in a reception mode of portions of said ultrasound beams transmitted along said first through third paths of propagation respectively, each of said first through third vectors including at least first, second and third values acquired at first, second and third ranges respectively; selecting said second values of said first and third vectors and said first through third values of said second vector; determining the middle value amongst said second values of said first and third vectors and said first through third values of said second vector; substituting said middle value for said second value of said second vector; and displaying image data which includes said middle value.
Claim 14
Dependent Claim
153 words
The method for reducing speckle artifact in an ultrasound image as defined in claim 11, further comprising the steps of: acquiring said first through third vectors of image data so that each of said first through third vectors includes first through N-th values acquired at first through N-th ranges respectively, where N is a positive integer; selecting the n-th values of said first and third vectors and the (n-1)-th, n-th and (n+1)-th values of said second vector, whereby a five-point kernel is formed for each n-th value in the range n=2 to (N-1) inclusive, where n is a positive integer; for each kernel, determining the middle value amongst said n-th values of said first and third vectors and said (n-1)-th, n-th and (n+1)-th values of said second vector; and for each kernel, substituting said respective middle value for said n-th value of said second vector, whereby a new filtered second vector is formed.
Claim 15
Dependent Claim
194 words
The method for reducing speckle artifact in an ultrasound image as defined in claim 12, further comprising the steps of: directing ultrasound beams along fourth through M-th paths of propagation; acquiring first through M-th vectors of image data, said first through M-th vectors corresponding to ultrasound beams directed along said first through M-th paths of propagation respectively, where M is a positive integer, each of said first through M-th vectors including first through N-th values acquired at first through N-th ranges respectively; selecting the n-th values of said (m-1)-th and (m+1)-th vectors and the (n-1)-th, n-th and (n+1)th values of said m-th vector, whereby a five-point kernel is formed for each n-th value in the range n=2 to (N-1) inclusive for each m-th vector in the range m=2 to (M-1) inclusive, where m is a positive integer; for each kernel, determining the middle value amongst said n-th values of said (m-1)-th and (m+1)-th vectors and the (n-1)-th, n-th and (n+1)-th values of said m-th vector; and for each kernel, substituting said respective middle value for said n-th value of said m-th vector, whereby a new set of filtered second to (M-1)-th vectors are formed.
Claim 16
Dependent Claim
43 words
The method for reducing speckle artifact in an ultrasound image as defined in claim 13, further comprising the step of generating addresses used to map said new set of filtered second to (M-1)-th vectors into pixel values at given X-Y coordinates for display.
Claim 17
Dependent Claim
17 words
The ultrasound imaging system as defined in claim 11, wherein said image data comprises ultrasound amplitude data.
Claim 18
Dependent Claim
18 words
The ultrasound imaging system as defined in claim 11, wherein said image data comprises ultrasound Doppler shift data.
References Cited (Backward Citations)
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| 3.5 Years (Year 4) | 1998-04-24 | 1998-10-24 | 1999-04-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2002-04-24 | 2002-10-24 | 2003-04-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2006-04-24 | 2006-10-24 | 2007-04-25 | $7700.00 | Window Closed / Lapsed |