US 12,423,780 B2
Wavelet denoising using signal location windowing
Madhur Srivastava, Ithaca, NY (US); and Jack H. Freed, Ithaca, NY (US)
Assigned to CORNELL UNIVERSITY, Ithaca, NY (US)
Appl. No. 18/012,426
Filed by CORNELL UNIVERSITY, Ithaca, NY (US)
PCT Filed Jun. 24, 2021, PCT No. PCT/US2021/038933
§ 371(c)(1), (2) Date Dec. 22, 2022,
PCT Pub. No. WO2021/263006, PCT Pub. Date Dec. 30, 2021.
Claims priority of provisional application 63/043,447, filed on Jun. 24, 2020.
Prior Publication US 2023/0260087 A1, Aug. 17, 2023
Int. Cl. G06T 5/70 (2024.01); G06F 17/14 (2006.01)
CPC G06T 5/70 (2024.01) [G06F 17/148 (2013.01); G06T 2207/20016 (2013.01); G06T 2207/20064 (2013.01)] 32 Claims
OG exemplary drawing
 
1. A method of denoising a signal comprising:
transforming a signal using an undecimated discrete wavelet transformation into at least a first wavelet component, the first wavelet component having a plurality of coefficients, the first wavelet component having a plurality of decomposition level, where a number of the plurality of coefficients in each level are the same;
for each decomposition level determined for thresholding, comparing each coefficient of the plurality of coefficients with a threshold, and selectively changing a value of the coefficient based on the comparison thereby generating a first modified first wavelet component having changed coefficients and unchanged coefficients for a decomposition level;
positioning one or more windows on the first modified first wavelet component for a highest decomposition level determined for thresholding, by evaluating the changed coefficients and unchanged coefficients in the first modified first wavelet component for the highest decomposition level;
changing coefficients in the first modified first wavelet component for the highest decomposition level determined for thresholding to its original value when the coefficients are within the one or more windows while keeping the coefficients outside the one or more windows the same as in the first modified first wavelet component to generate a second modified first wavelet component for the highest decomposition level determined for thresholding;
positioning the one or more windows on the first modified first wavelet component for a subset of other decomposition levels of the plurality of decomposition levels at the same positions;
changing coefficients in the first modified first wavelet component for each of the subset of other decomposition levels to its original value when the coefficients are within the one or more windows while keeping the coefficients outside the one or more windows the same as the first modified first wavelet component to generate a third modified first wavelet component, respectively, for each decomposition level of the subset of other decomposition levels; and
transforming, using an inverse undecimated discrete wavelet transformation, the first modified first wavelet component for decomposition levels other than the subset of other decomposition levels and the highest decomposition level, respectively, the second modified first wavelet component for the highest decomposition level and the third modified first wavelet component for the subset of other decomposition levels, respectively, into a denoised signal.