Method for ultrasonic panoramic imaging
AssigneeMedlander Medical Technology Inc.
InventorsKun Peng, Feng Yin
Life of this patent
Estimating the term…
Abstract
The present application discloses a method for ultrasonic panoramic imaging. Through processes such as coordinate mapping calculation, interpolation, and secondary correction of two images, the to-be-stitched image becomes more accurate, and it is also possible to avoid problems that may arise from noise, tissue movement leading to abnormal images. Furthermore, after a first stitching is completed, the to-be-stitched image is saved as a reference image for use in a next registration. Due to the improved accuracy of the reference image, the continuity and accuracy of subsequent panoramic imaging processes can be ensured.
Claims10
A method for ultrasonic panoramic imaging, comprising:
- (1) acquiring one frame from to-be-stitched images, determining whether this frame is a first frame among a plurality of the to-be-stitched images, and directly using it as an initial reference image C if it is the first frame or otherwise proceeding to step (2) if it is not the first frame;
- (2) acquiring an image A other than the reference image C, expanding a perimeter of the image A based on values of neighboring pixels thereof to generate an image A*, and expanding a perimeter of the reference image C based on values of neighboring pixels thereof to generate an image C*;
- (3) dividing the image A* and the image C* equally into n areas, calculating by a sum of absolute differences (SAD) method an average offset of image A* relative to the image C* in each area, where n is a positive integer;
- (4) obtaining average offset values in X and Y directions of image coordinates in image A* relative to the image C* for each of the n areas, adding corresponding average offsets to the coordinates of the center points of each area respectively to acquire a new coordinate of n points for the image A relative to the image C, obtaining average offsets of the overall image by averaging the new coordinates of the n points, and obtaining coordinate mapping values for all points of image A relative to the image C after interpolation is performed on the new coordinates of the n points;
- (5) traversing each pixel of the image A based on the obtained coordinate mapping values, performing a mapping thereon according to corresponding coordinates and deforming it into a registered image B;
- (6) traversing each pixel of the registered image B and the reference image C by calculating a difference of pixels at corresponding positions to obtain a set of pixel differences;
- traversing the set of pixel differences by comparing the set with 99 respectively and taking the smaller value to obtain a new set of differences;
- (7) obtaining a lookup table based on a calibration curve;
- (8) correcting the registered image B to obtain a to-be-stitched image B*;
- and
- (9) stitching, by weighted average method for overlapping areas, the to-be-stitched image B* with one previous panoramic resulting image C based on overall average offset, to obtain a composite image D.
Dependencies are inferred from the claim text.