Image registration using fourier phase matching

A system for image frame registration comprising:

• a memory for storing first and second image frames of pixel values;
• and
• an image registration processor programmed to perform the steps of:
• (a) transforming said first and second image frames into first and second frequency domain representations respectively using a two-dimensional Fast Fourier transformation;
• (b) processing said first and second frequency domain representations to determine a rotation parameter and a scaling parameter needed for said first image frame to be in registration with said second image frame;
• (c) rotating said first image frame in accordance with said rotation parameter;
• and
• (d) scaling said first image frame in accordance with said scaling parameter.

An ultrasound imaging system comprising:

• an ultrasound transducer array comprising a multiplicity of transducer elements;
• a transmit beamformer for pulsing selected transducer elements during first and second series of transmit firings constituting first and second scans respectively;
• a receive beamformer coupled to selected transducer elements of said transducer array for acquiring a respective receive signal subsequent to each transmit firing;
• a signal processor programmed to form first and second sets of processed signals from said receive signals for said first and second scans respectively;
• a converter for converting said first and second sets of processed signals into said first and second image frames respectively;
• a memory for storing first and second image frames of pixel values;
• and
• a computer programmed to rotate, scale and translate said second image frame to be in registration with said first image frame based on phase matching of frequency domain representations derived from said first and second image frames, and produce a final image frame of pixel data which is a function of said first image frame and said rotated, scaled and translated second image frame;
• and
• a display device comprising a multiplicity of pixels for displaying said final image frame.

An ultrasound imaging system comprising:

• a memory for storing first and second image frames of ultrasound pixel data;
• a computer programmed to rotate, scale and translate said second image frame to be in registration with said first image frame based on phase matching of frequency domain representations derived from said first and second image frames, and produce a final image frame of pixel data which is a function of said first image frame and said rotated, scaled and translated second image frame;
• and
• a display device comprising a multiplicity of pixels for displaying said final image frame.

A method for ultrasound imaging comprising the steps of:

• storing first and second image frames of ultrasound imaging data;
• rotating, scaling and translating said second image frame to be in registration with said first image frame based on phase matching of frequency domain representations derived from said first and second image frames;
• producing a final image frame of pixel data which is a function of said first image frame and said rotated, scaled and translated second image frame;
• and
• displaying said final image frame.

An imaging system comprising:

• a memory for storing first and second image frames of pixel values;
• a computer programmed to perform the steps of:
• (a) transforming said first and second image frames into first and second frequency domain representations respectively using a two-dimensional Fast Fourier transformation;
• (b) processing said first and second frequency domain representations to determine a rotation parameter and a scaling parameter needed for said first image frame to be in registration with said second image frame;
• (c) rotating said first image frame in accordance with said rotation parameter;
• (d) scaling said first image frame in accordance with said scaling parameter;
• and
• (e) producing a final image frame of pixel data which is a function of said rotated and scaled first image frame and said second image frame;
• and
• a display device comprising a multiplicity of pixels for displaying said final image frame.

An imaging system comprising:

• a memory for storing first and second image frames of pixel values;
• means for transforming said first and second image frames into first and second frequency domain representations respectively using a two-dimensional Fast Fourier transformation;
• means for processing said first and second frequency domain representations to determine a rotation parameter and a scaling parameter needed for said first image frame to be in registration with said second image frame;
• means for rotating said first image frame in accordance with said rotation parameter;
• means for scaling said first image frame in accordance with said scaling parameter;
• and
• means for producing a final image frame of pixel data which is a function of said rotated and scaled first image frame and said second image frame;
• and
• a display device comprising a multiplicity of pixels for displaying said final image frame.

A method for image frame registration, comprising the steps of:

• storing first and second image frames of pixel values;
• edge detecting said first and second image frames to form first and second edge-detected image frames respectively;
• transforming said first and second edge-detected image frames into first and second frequency domain representations respectively using a two-dimensional Fast Fourier transformation;
• processing said first and second frequency domain representations to determine a rotation parameter and a scaling parameter needed for said first image frame to be in registration with said second image frame;
• rotating said first image frame in accordance with said rotation parameter;
• and
• scaling said first image frame in accordance with said scaling parameter.

A system for image frame registration comprising:

• a memory for storing first and second image frames of pixel values;
• and
• an image registration processor programmed to perform the steps of:
• (a) edge detecting said first and second image frames to form first and second edge-detected image frames respectively;
• (b) transforming said first and second edge-detected image frames into first and second frequency domain representations respectively using a two-dimensional Fast Fourier transformation;
• (c) processing said first and second frequency domain representations to determine a rotation parameter and a scaling parameter needed for said first image frame to be in registration with said second image frame;
• (d) rotating said first image frame in accordance with said rotation parameter;
• and
• (e) scaling said first image frame in accordance with said scaling parameter.