| CPC G06T 1/005 (2013.01) [G01N 29/0645 (2013.01); G01N 29/2437 (2013.01); G06T 1/0028 (2013.01); G10L 19/018 (2013.01); G01N 2291/0234 (2013.01); G01N 2291/106 (2013.01); G06T 2201/0052 (2013.01); G06T 2201/0065 (2013.01); G06T 2201/0202 (2013.01)] | 20 Claims |
|
1. A method comprising:
providing acoustic data comprising time-series representation of acoustic echo signals from an object under inspection using an acoustic transducer array, the acoustic data being arranged in a 3D arrangement;
generating a first volume of slices based on the acoustic data, the first volume slices comprising 2D slices, wherein a parameter of the 2D slices is based on a number of elements of the acoustic transducer array;
for each of the first volume of slices:
transforming a respective slice into a frequency domain representation using a discrete transform to obtain a respective transformed slice,
embedding a portion of a digital watermark into the transformed slice, wherein the digital watermark is based on a key, the embedding comprising:
determining an energy level of the transformed slice, and
setting a strength coefficient for application of the key for the transformed slice based on the energy level of the transformed slice, and
applying an inverted form of the discrete transform to the transformed slice with the embedded portion of the digital watermark to generate a respective marked slice;
arranging respective marked slices with respective embedded portions of the digital watermark into a second volume of marked slices; and
generating an image based on the second volume of marked slices, wherein the image illustrates echo representations from the object.
|