Methods and systems for filtering ultrasound image clutter

1. A method for generating a filtered ultrasound image, the method comprising:

obtaining channel data from an ultrasonic transducer array;

generating first image data from the channel data using a first apodization function;

generating second image data from the channel data using a second apodization function, wherein the second apodization function comprises a null filter exhibiting a null at a lobe location;

applying a minimizing function to the first and second image data;

generating third image data based on the minimized first and second image data; and

generating the filtered ultrasound image based on the first and third image data, wherein the generation of the filtered ultrasound image comprises:

subtracting the pixel values of the third image data from the pixel values of the first image data, thereby generating filtered pixels; and

constructing the filtered ultrasound image using the filtered pixels.

2. The method as claimed in claim 1 , wherein the minimization function comprises: comparing the first and second image data; and

for each pair of pixels from the first and second image data, selecting a pixel with the minimum pixel value based on the comparison.

3. The method as claimed in claim 2 , wherein the generation of the third image data comprises:

constructing the third image data using the selected pixels.

4. The method as claimed in claim 1 , wherein the method further comprises performing a log compression on the filtered ultrasound image.

5. The method as claimed in claim 1 , wherein the first apodization function comprises a rectangular function.

6. The method as claimed in claim 1 , wherein a scaling factor of the second apodization function is variable.

7. The method as claimed in claim 1 , wherein the method further comprises applying DAS beamforming to the first and second image data, the DAS beamforming comprising:

before the steps of generating the first and second image data, delaying the channel data;

after the steps of generating the first and second image data, summing the first image data and summing the second image data, respectively.

8. The method as claimed in claim 1 , wherein the method further comprises applying envelope detection to the first and second image data.

9. A computer program comprising computer program code means which is adapted, when said computer is run on a computer, to implement the method of claim 1 .

10. A method for generating a filtered ultrasound image, the method comprising:

obtaining channel data from an ultrasonic transducer array;

generating first image data from the channel data using a first apodization function;

generating second image data from the channel data using a second apodization function, wherein the second apodization function comprises a null filter;

applying a minimizing function to the first and second image data;

generating third image data based on the minimized first and second image data; and

generating the filtered ultrasound image based on the first and third image data, wherein the generation of the filtered ultrasound image comprises:

subtracting the pixel values of the third image data from the pixel values of the first image data, thereby generating filtered pixels; and

constructing the filtered ultrasound image using the filtered pixels, wherein the method further comprises performing a log compression on the filtered ultrasound image; and

wherein the method, after the step of performing a log compression on the filtered ultrasound image, further comprises:

applying a spatial low pass filter to the first image data;

applying a spatial low pass filter to the filtered ultrasound image;

generating a detail component of the first image data by subtracting the spatial low pass filtered first image data from the first image data; and

combining the detail component of the first image data with the spatial low pass filtered version of the filtered ultrasound image.

11. A controller for generating a filtered ultrasound image in an ultrasound system, wherein the controller is coupled to an ultrasonic transducer array and adapted to:

obtain channel data from the ultrasonic transducer array;

generate first image data from the channel data using a first apodization function;

generate second image data from the channel data using a second apodization function, wherein the second apodization function comprises a null filter exhibiting a null at a lobe location;

apply a minimizing function to the first and second image data;

generate third image data based on the minimized first and second image data; and

generate the filtered ultrasound image based on the first and third image data, wherein during the generation of the filtered ultrasound image the controller is further adapted to:

subtract the pixel values of the third image data from the pixel values of the first image data, thereby generating filtered pixels; and

construct the filtered ultrasound image using the filtered pixels.

12. An ultrasound system comprising:

an ultrasonic transducer array, wherein the ultrasonic transducer array is capable of emitting and receiving ultrasonic signals, based on which channel data are obtained;

a signal processor for compiling the received ultrasonic signals into an ultrasound image;

a controller as claimed in claim 11 ; and

an image output device for outputting the filtered ultrasound image.

13. The ultrasound system as claimed in claim 12 , wherein the ultrasound system further comprises:

a filter design processor, wherein the filter design processor is adapted to alter the second apodization function.