Ultrasound imaging method, apparatus, device, and storage medium

Abstract

The application relates to the technical field of signal processing, and discloses an ultrasonic imaging method, device, equipment and storage medium, the method comprising the following steps: acquiring a first time-domain ultrasonic signal received by a receiving array element in an ultrasonic array; performing Fourier transform on the first time-domain ultrasonic signal to obtain a first frequency-domain ultrasonic signal; acquiring a first apodization coefficient and a first signal transmission delay of a transmitting array element in the ultrasonic array; processing the first frequency-domain ultrasonic signal based on the first apodization coefficient and the first signal transmission delay to obtain a second frequency-domain ultrasonic signal corresponding to the transmitting array element of the receiving array element; performing inverse Fourier transform on the second frequency-domain ultrasonic signal to obtain a second time-domain ultrasonic signal; and performing beam synthesis based on the second time-domain ultrasonic signal to obtain an ultrasonic image. The application can solve the problem of unstable image quality of an ultrasonic image generated by dynamic focusing.

Description

Technical Field

[0001] This invention relates to the field of signal processing technology, and more specifically to ultrasonic imaging methods, apparatus, devices, and storage media. Background Technology

[0002] Ultrasound imaging typically employs focused wave emission. Each time a focused wave is emitted, a dynamically focused wave is received at the corresponding location to synthesize a scan line. Then, multiple synthesized scan lines are stitched together to form a complete ultrasound image, following the geometrical movement sequence during focused wave emission. However, since a single focused wave emission can only focus at one depth, and ultrasound images typically achieve optimal resolution only at the focal point, the resolution of ultrasound images is poor at locations far from the focal point. Therefore, related technologies propose synthesizing multiple scan lines after a single focused wave emission, achieving dynamic focusing through a weighted summation of the multiple scan lines obtained from different emission emission methods to improve ultrasound image quality. However, this dynamic focusing ultrasound imaging method relies heavily on the combination of parameters such as the number of scan lines synthesized in a single emission, the position of the synthesized scan lines in a single emission, the optimization of the weighting coefficients, the number of emission emission cycles for weighted summation, and the corresponding emission line number, leading to unstable image quality in the generated ultrasound images. Summary of the Invention

[0003] In view of this, the present invention provides an ultrasound imaging method, apparatus, device and storage medium to solve the problem of unstable image quality of ultrasound images generated by dynamic focusing.

[0004] In a first aspect, the present invention provides an ultrasound imaging method, the method comprising:

[0005] Acquire the first time-domain ultrasonic signal received by the receiving element in the ultrasonic array;

[0006] Perform a Fourier transform on the first time-domain ultrasonic signal to obtain the first frequency-domain ultrasonic signal;

[0007] Obtain the first apodization coefficient and the first signal transmission delay of the transmitting element in the ultrasonic array;

[0008] Based on the first apodization coefficient and the first signal transmission delay, the first frequency domain ultrasonic signal is processed to obtain the second frequency domain ultrasonic signal of the receiving array element corresponding to the transmitting array element.

[0009] Perform an inverse Fourier transform on the second frequency domain ultrasonic signal to obtain the second time domain ultrasonic signal;

[0010] Beamforming is performed based on the second time-domain ultrasonic signal to obtain an ultrasonic image.

[0011] In this method, only the first time-domain ultrasonic signal received by the receiving element in the ultrasonic array, the first apodization coefficient of the transmitting element, and the first signal transmission delay are needed. Then, the second frequency-domain ultrasonic signal corresponding to the transmitting element can be calculated by inversely using the first time-domain ultrasonic signal, the first apodization coefficient, and the first signal transmission delay. This allows for the generation of the second time-domain ultrasonic signal based on inverse Fourier transform. An ultrasonic image is then obtained by beamforming the second time-domain ultrasonic signal. Therefore, it eliminates the need to rely on the combination of parameters such as the number of scan lines in a single transmission, the position of the scan lines in a single transmission, the optimization of weighting coefficients, the number of transmissions for weighted summation, and the corresponding transmission line number, thus ensuring the stability of the image quality of the ultrasonic image ultimately generated by dynamic focusing.

[0012] In one optional implementation, processing the first frequency-domain ultrasonic signal based on the first apodization coefficient and the first signal transmission delay to obtain the second frequency-domain ultrasonic signal corresponding to the transmitting element of the receiving array element includes:

[0013] A first ultrasonic signal matrix is ​​constructed using the first frequency domain ultrasonic signal corresponding to the receiving array element as elements;

[0014] Based on the first apodization coefficient and the first signal transmission delay of the transmitting array element, the signal weighting coefficient of the transmitting array element is calculated;

[0015] A weighting coefficient matrix is ​​constructed using the signal weighting coefficients of the aforementioned transmitting array elements.

[0016] The second ultrasound signal matrix is ​​obtained by calculating based on the first ultrasound signal matrix and the weighting coefficient matrix.

[0017] From the second ultrasonic signal matrix, the second frequency domain ultrasonic signal corresponding to the transmitting element of the receiving element is obtained, and the second frequency domain ultrasonic signal corresponding to the transmitting element of the receiving element is an element of the second ultrasonic signal matrix.

[0018] In this method, the signal weighting coefficient of the transmitting array element is calculated by using the first apodization coefficient and the first signal transmission delay. Then, based on linear acoustic theory, the second frequency domain ultrasonic signal of the receiving array element corresponding to the transmitting array element is obtained by inverse solution based on the first ultrasonic signal matrix and the weighting coefficient matrix corresponding to the first frequency domain ultrasonic signal and the signal weighting coefficient. The calculation process is simple.

[0019] In one alternative implementation, the signal weighting coefficients are calculated using the following formula:

[0020]

[0021] Among them, cm,i a is the signal weighting coefficient of the i-th transmitting element during the m-th ultrasonic wave transmission. m,i σt is the first apodization coefficient of the i-th transmitting element during the m-th ultrasonic wave transmission. m,i ω is the first signal transmission delay of the i-th transmitting array element during the m-th ultrasonic wave transmission, where ω is the angular frequency and j is the imaginary number.

[0022] In this method, since the ultrasonic signal emitted by the transmitting element is delayed to a certain extent when it is received by the receiving element, and each receiving element contributes differently to the final beamformed ultrasonic image, the signal weighting coefficient corresponding to the transmitting element is calculated based on the first apodization coefficient and the first signal transmission delay of the transmitting element at each ultrasonic transmission. This is to recover the second frequency domain ultrasonic signal of the receiving element corresponding to the transmitting element, thereby improving the image quality of the final beamformed ultrasonic image to a certain extent.

[0023] In one optional implementation, the step of calculating the second ultrasound signal matrix based on the first ultrasound signal matrix and the weighting coefficient matrix includes:

[0024] Obtain the number of rows and columns of the first ultrasound signal matrix or the weighting coefficient matrix;

[0025] Based on the relationship between the number of rows and the number of columns, the first ultrasonic signal matrix and the weighting coefficient matrix are calculated to obtain the second ultrasonic signal matrix.

[0026] In this method, the first ultrasound signal matrix and the weighting coefficient matrix are calculated based on the relationship between the number of rows and columns of the first ultrasound signal matrix or the weighting coefficient matrix to obtain the second ultrasound signal matrix. Therefore, the calculation process of the second ultrasound signal matrix can be simplified to a certain extent and the calculation efficiency can be improved.

[0027] In one optional implementation, the step of calculating the second ultrasound signal matrix based on the relationship between the number of rows and the number of columns, using the first ultrasound signal matrix and the weighting coefficient matrix, includes:

[0028] When the number of rows is greater than or equal to the number of columns, the first ultrasonic signal matrix and the weighting coefficient matrix are calculated based on the least squares method or regularization optimization algorithm to obtain the second ultrasonic signal matrix;

[0029] When the number of rows is less than the number of columns, the first ultrasound signal matrix and the weighting coefficient matrix are calculated based on norm minimization to obtain the second ultrasound signal matrix.

[0030] In this approach, an appropriate matrix solving method is adaptively selected based on the relationship between the number of rows and columns of the first ultrasonic signal matrix or the weighted coefficient matrix, thereby reducing the difficulty of solving the second ultrasonic signal matrix.

[0031] In one optional implementation, the step of beamforming based on the second time-domain ultrasound signal to obtain an ultrasound image includes:

[0032] Obtain the second apodization coefficient and the second signal transmission delay of the receiving array element corresponding to the transmitting array element;

[0033] Based on the second apodization coefficient and the second signal transmission delay, beamforming is performed on the second time-domain ultrasonic signal of the receiving array element corresponding to the transmitting array element to obtain the beamforming signal of the target imaging region.

[0034] The beamforming signal is subjected to envelope extraction and logarithmic compression to obtain an ultrasound image.

[0035] In this method, based on the second apodization coefficient and the second signal transmission delay of the receiving array element corresponding to the transmitting array element, the second time-domain ultrasound signal of the receiving array element corresponding to the transmitting array element is subjected to delayed superposition beamforming. Therefore, it is possible to improve the image quality of the ultrasound image in a dynamic focusing manner while reducing the sidelobe level of the beamforming signal, thereby further improving the image quality of the ultrasound image.

[0036] In one optional implementation, the beamforming signal of the target imaging region is calculated using the following formula:

[0037]

[0038] in, Location in the target imaging region The beamforming signal, where N is the total number of elements in the ultrasonic array, w i,k tp is the second apodization coefficient corresponding to the i-th transmitting element for the k-th receiving element. i,k Location of the target imaging region When the second signal transmission delay of the k-th receiving array element corresponds to that of the i-th transmitting array element, x i,k The second time-domain ultrasonic signal of the k-th receiving array element corresponds to the i-th transmitting array element, where t is the time.

[0039] In a second aspect, the present invention provides an ultrasound imaging device, the device comprising:

[0040] The signal acquisition module is used to acquire the first time-domain ultrasonic signal received by the receiving element in the ultrasonic array;

[0041] The first transformation module is used to perform a Fourier transform on the first time-domain ultrasonic signal to obtain a first frequency-domain ultrasonic signal;

[0042] The parameter acquisition module is used to acquire the first apodization coefficient and the first signal transmission delay of the transmitting array element in the ultrasonic array;

[0043] The reverse solving module is used to process the first frequency domain ultrasonic signal based on the first apodization coefficient and the first signal transmission delay to obtain the second frequency domain ultrasonic signal of the receiving array element corresponding to the transmitting array element.

[0044] The second transformation module is used to perform an inverse Fourier transform on the second frequency domain ultrasonic signal to obtain a second time domain ultrasonic signal.

[0045] The beamforming module is used to perform beamforming based on the second time-domain ultrasound signal to obtain an ultrasound image.

[0046] Thirdly, the present invention provides a computer device, comprising: a memory and a processor, the memory and the processor being communicatively connected to each other, the memory storing computer instructions, and the processor executing the computer instructions to perform the ultrasound imaging method of the first aspect or any corresponding embodiment described above.

[0047] Fourthly, the present invention provides a computer-readable storage medium storing computer instructions for causing a computer to perform the ultrasound imaging method of the first aspect or any corresponding embodiment thereof. Attached Figure Description

[0048] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0049] Figure 1 This is a schematic flowchart of a first ultrasound imaging method according to an embodiment of the present invention;

[0050] Figure 2 This is a schematic flowchart of a second ultrasound imaging method according to an embodiment of the present invention;

[0051] Figure 3 This is a flowchart illustrating the third ultrasound imaging method according to an embodiment of the present invention;

[0052] Figure 4 This is a schematic flowchart of the fourth ultrasound imaging method according to an embodiment of the present invention;

[0053] Figure 5 This is a structural block diagram of an ultrasound imaging device according to an embodiment of the present invention;

[0054] Figure 6 This is a schematic diagram of the hardware structure of a computer device according to an embodiment of the present invention. Detailed Implementation

[0055] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0056] Related technologies synthesize multiple scan lines after emitting a single focused wave, and achieve dynamic focusing of the emission by weighted summation of multiple scan lines obtained from different emission to improve the quality of ultrasound images. However, the ultrasound imaging method relies on the combination and selection of parameters such as the number of scan lines synthesized in a single emission, the position of the scan lines synthesized in a single emission, the optimization of the weighting coefficients, the number of emission for weighted summation, and the corresponding emission line number, which leads to unstable image quality of the generated ultrasound images.

[0057] In view of this, according to an embodiment of the present invention, an embodiment of an ultrasound imaging method is provided. It should be noted that the steps shown in the flowchart in the accompanying drawings can be executed in a computer system such as a set of computer-executable instructions. Furthermore, although a logical order is shown in the flowchart, in some cases, the steps shown or described may be executed in a different order than that shown here.

[0058] This embodiment provides an ultrasound imaging method that can be used in an ultrasound imaging device. Figure 1 This is a flowchart of a first ultrasound imaging method according to an embodiment of the present invention, as follows: Figure 1 As shown, the process includes the following steps:

[0059] Step S101: Obtain the first time-domain ultrasonic signal received by the receiving element in the ultrasonic array.

[0060] Step S102: Perform Fourier transform on the first time-domain ultrasonic signal to obtain the first frequency-domain ultrasonic signal.

[0061] Step S103: Obtain the first apodization coefficient and the first signal transmission delay of the transmitting element in the ultrasonic array.

[0062] It should be noted that the first apodization coefficient and the first signal transmission delay of the transmitting array element are not limited to focused wave transmission, but can also be applied to ultrasonic signal transmission methods such as plane wave transmission and spherical wave transmission.

[0063] In this embodiment, steps S101 to S102 are used to determine the first frequency domain ultrasonic signal, and step S103 is used to obtain the transmission array element parameters (including the first apodization coefficient and the first signal transmission delay). It can be understood that the process of determining the first frequency domain ultrasonic signal and the process of obtaining the transmission array element parameters can be executed in parallel or sequentially. This embodiment does not limit this, as long as the first apodization coefficient, the first signal transmission delay and the first frequency domain ultrasonic signal are obtained before executing step S104.

[0064] like Figure 1 As shown, the process of determining the first frequency domain ultrasonic signal and the process of obtaining the transmission array element parameters can be executed in parallel, that is, steps S101 to S102 and step S103 can be executed in parallel; or, steps S101, S102 and S103 can be executed in the order of step S103, S101 and S102. This embodiment does not limit the execution order.

[0065] Step S104: Process the first frequency domain ultrasonic signal based on the first apodization coefficient and the first signal transmission delay to obtain the second frequency domain ultrasonic signal of the receiving array element corresponding to the transmitting array element.

[0066] Step S105: Perform an inverse Fourier transform on the second frequency domain ultrasonic signal to obtain the second time domain ultrasonic signal.

[0067] For example, let the second frequency domain ultrasonic signal of the k-th receiving element corresponding to the i-th transmitting element be X. i,k (f), then for X i,k (f) Performing an inverse Fourier transform yields the second time-domain ultrasonic signal x corresponding to the i-th transmitting element for the k-th receiving element. i,k f(t) represents the ultrasonic echo signal emitted by the i-th transmitting element and received by the k-th receiving element; where f is the frequency.

[0068] Step S106: Beamforming is performed based on the second time-domain ultrasound signal to obtain an ultrasound image.

[0069] The ultrasound imaging method provided in this embodiment only needs to obtain the first time-domain ultrasound signal received by the receiving element in the ultrasound array, the first apodization coefficient of the transmitting element, and the first signal transmission delay. It can then inversely solve for the second frequency-domain ultrasound signal corresponding to the transmitting element based on the first time-domain ultrasound signal, the first apodization coefficient, and the first signal transmission delay. Furthermore, it obtains the second time-domain ultrasound signal based on inverse Fourier transform, and then performs beamforming on the second time-domain ultrasound signal to obtain an ultrasound image. Therefore, it does not rely on the combination and selection of parameters such as the number of scan lines synthesized in a single transmission, the position of the scan lines synthesized in a single transmission, the optimization of weighting coefficients, the number of transmissions for weighted summation, and the corresponding transmission line number, thereby ensuring the stability of the image quality of the ultrasound image ultimately generated by dynamic focusing.

[0070] Figure 2 This is a flowchart of a second ultrasound imaging method according to an embodiment of the present invention, such as... Figure 2 As shown, step S104 above includes:

[0071] Step S1041: Construct a first ultrasonic signal matrix using the first frequency domain ultrasonic signal corresponding to the receiving array element as the element.

[0072] Specifically, assuming the total number of array elements in the ultrasonic array is N, and the number of ultrasonic wave transmissions is M, let the first time-domain ultrasonic signal received by the k-th receiving array element during the m-th ultrasonic wave transmission be y. m,k (t), then for y m,k After performing a Fourier transform on (t), the first frequency domain ultrasonic signal Y corresponding to the k-th receiving element at the m-th ultrasonic transmission can be obtained. m,k (f), Y m,k (f) is used as an element of the first ultrasound signal matrix to construct a first ultrasound signal matrix Y(f) of size M*N.

[0073] For example, such as Figure 2 As shown, after obtaining the first frequency domain ultrasound signal in step S102, step S1041 can be executed to construct the first ultrasound signal matrix.

[0074] Step S1042: Calculate the signal weighting coefficient of the transmitting array element based on the first apodization coefficient and the first signal transmission delay.

[0075] Specifically, the signal weighting coefficients in step S1042 above are calculated using the following formula:

[0076]

[0077] Among them, c m,i Let a be the signal weighting coefficient of the i-th transmitting element during the m-th ultrasonic wave transmission. m,iLet σt be the first apodization coefficient of the i-th transmitting element during the m-th ultrasonic wave transmission. m,i ω represents the first signal transmission delay of the i-th transmitting element during the m-th ultrasonic wave transmission, where ω is the angular frequency and j is the imaginary number.

[0078] Step S1043: Construct a weighted coefficient matrix using the signal weighting coefficients of the transmitting array elements as elements.

[0079] It should be noted that the first ultrasound signal matrix and the weighting coefficient matrix have the same number of rows and columns.

[0080] Specifically, with c m,i Construct a signal weighting vector for the m-th ultrasonic wave emission for each element. The signal weighting vector C corresponding to the m-th ultrasonic wave emission is... m As elements of the m-th row of the weighted coefficient matrix, construct a weighted coefficient matrix C of size M*N.

[0081] For example, such as Figure 2 As shown, after obtaining the first apodization coefficient and the first signal transmission delay in step S103, steps S1042 and S1043 can be executed to construct the weighted coefficient matrix.

[0082] It is understandable that the first ultrasound signal matrix and the weighting coefficient matrix can be constructed in parallel, i.e., as follows: Figure 2 As shown, steps S1041 and S1042 to S1043 are executed in parallel. Alternatively, the two matrices can be constructed sequentially; for example, the first ultrasound signal matrix can be constructed first, followed by the weighting coefficient matrix, i.e., step S1041 is executed first, followed by steps S1042 to S1043; or, the weighting coefficient matrix can be constructed first, followed by the first ultrasound signal matrix, i.e., steps S1042 to S1043 are executed first, followed by step S1041. This embodiment does not limit the execution order, as long as the first ultrasound signal matrix and the weighting coefficient matrix are constructed before step S1044.

[0083] Step S1044: Calculate the second ultrasound signal matrix based on the first ultrasound signal matrix and the weighting coefficient matrix.

[0084] Specifically, the first ultrasound signal matrix is ​​equal to the product of the weighting coefficient matrix and the second ultrasound signal matrix.

[0085] It should be noted that, according to linear acoustic theory x i,k (t) and y m,k (t) has the following relation: right Performing a Fourier transform yields: Y m.k (f)=Cm X k (f); where X k (f) = [X 1,k (f),X 2,k (f),...,X i,k (f),...,X N,k (f)]T,X i,k (f) represents the second frequency domain ultrasonic signal corresponding to the i-th transmitting element for the k-th receiving element, X. k (f) is the second frequency domain ultrasonic vector corresponding to the k-th receiving element and all transmitting elements. Let X be the second frequency domain ultrasonic vector corresponding to the k-th receiving element and all transmitting elements. k (f) is the element of the k-th column of the second ultrasonic signal matrix, which yields a second ultrasonic signal matrix X(f) of size N*N. Assuming the number of ultrasonic wave transmissions is M, then for M ultrasonic wave transmissions, the above relationship exists for all N receiving elements in the ultrasonic array, i.e., Y(f) = CX(f). Therefore, the second ultrasonic signal matrix can be obtained by inversely solving the first ultrasonic signal matrix and the weighting coefficient matrix, and the second frequency domain ultrasonic signal corresponding to the transmitting element can be extracted from the second ultrasonic signal matrix.

[0086] Step S1045: Obtain the second frequency domain ultrasonic signal corresponding to the transmitting element from the receiving element in the second ultrasonic signal matrix. The second frequency domain ultrasonic signal corresponding to the transmitting element is an element of the second ultrasonic signal matrix.

[0087] The ultrasonic imaging method provided in this embodiment calculates the signal weighting coefficient of the transmitting array element by using the first apodization coefficient and the first signal transmission delay. Then, based on linear acoustic theory, and using the first ultrasonic signal matrix and weighting coefficient matrix corresponding to the first frequency domain ultrasonic signal and the signal weighting coefficient, the second frequency domain ultrasonic signal of the receiving array element corresponding to the transmitting array element is obtained by reverse calculation. The calculation process is simple.

[0088] Figure 3 This is a flowchart of a third ultrasound imaging method according to an embodiment of the present invention, such as... Figure 3 As shown, step S1044 above includes:

[0089] Step a1: Obtain the number of rows and columns of the first ultrasound signal matrix or weighted coefficient matrix.

[0090] Step a2: Based on the relationship between the number of rows and columns, calculate the first ultrasound signal matrix and the weighting coefficient matrix to obtain the second ultrasound signal matrix.

[0091] It should be noted that the number of rows in the first ultrasound signal matrix and the weighting coefficient matrix is ​​the number of times ultrasound waves were emitted when the ultrasound image was generated, and the number of columns in the first ultrasound signal matrix and the weighting coefficient matrix is ​​the total number of array elements in the ultrasound array.

[0092] It should be noted that the elements of an ultrasonic array can act as transmitting elements to emit ultrasonic waves or as receiving elements to receive ultrasonic echo signals, thus achieving single-element transmission and single-element reception of ultrasonic signals. Therefore, the total number of elements in an ultrasonic array is the same as the total number of transmitting elements and the total number of receiving elements.

[0093] The ultrasound imaging method provided in this embodiment calculates the first ultrasound signal matrix and the weighting coefficient matrix based on the relationship between the number of rows and columns of the first ultrasound signal matrix or the weighting coefficient matrix to obtain the second ultrasound signal matrix. Therefore, it can simplify the calculation process of the second ultrasound signal matrix to a certain extent and improve the calculation efficiency.

[0094] Furthermore, step a2 above includes:

[0095] Step a21: When the number of rows is greater than or equal to the number of columns, the first ultrasonic signal matrix and the weighted coefficient matrix are calculated based on the least squares method or regularization optimization algorithm to obtain the second ultrasonic signal matrix.

[0096] It should be noted that when the number of rows is greater than or equal to the number of columns, the above formula Y(f)=CX(f) is an overdetermined system of equations. Therefore, the least squares method or regularization optimization algorithm can be used to calculate the first ultrasonic signal matrix and the weighting coefficient matrix to obtain the second ultrasonic signal matrix.

[0097] Step a22: When the number of rows is less than the number of columns, the first ultrasound signal matrix and the weighting coefficient matrix are calculated based on norm minimization to obtain the second ultrasound signal matrix.

[0098] It should be noted that when the number of rows is less than the number of columns, the above formula Y(f)=CX(f) is an underdetermined system of equations. Therefore, a norm minimization optimization algorithm can be used to solve it. Preferably, an L1 norm minimization optimization algorithm, such as the basis pursuit algorithm, is used.

[0099] Furthermore, step a21 above includes:

[0100] Step a211: When the number of rows is greater than or equal to the number of columns, calculate the transpose of the weighted coefficient matrix.

[0101] Step a212: Calculate the product of the transpose of the weighted coefficient matrix and the weighted coefficient matrix to obtain the target matrix.

[0102] Step a213: When the condition number of the target matrix is ​​less than or equal to a preset threshold, the first ultrasonic signal matrix and the weighting coefficient matrix are calculated based on the least squares method to obtain the second ultrasonic signal matrix.

[0103] Specifically, step a213 above calculates the second ultrasound signal matrix using the following formula:

[0104] X(f)=(C T C) -1 C T Y(f);

[0105] Among them, C T This is the transpose of the weighted coefficient matrix.

[0106] Step a214: When the condition number of the target matrix is ​​greater than the preset threshold, the first ultrasonic signal matrix and the weighting coefficient matrix are calculated based on the regularization optimization algorithm to obtain the second ultrasonic signal matrix.

[0107] Specifically, step a214 above calculates the second ultrasound signal matrix using the following formula:

[0108] X(f)=(C T C+λI) -1 C T Y(f);

[0109] Where I is an N*N identity matrix and λ is the regularization coefficient.

[0110] Figure 4 This is a flowchart of the fourth ultrasound imaging method according to an embodiment of the present invention, such as... Figure 4 As shown, step S106 above includes:

[0111] Step S1061: Obtain the second apodization coefficient and the second signal transmission delay of the receiving array element corresponding to the transmitting array element.

[0112] Specifically, the second signal transmission delay is obtained using the following formula:

[0113]

[0114] Among them, tp i,k Location of the target in the imaging region The second signal transmission delay of the k-th receiving element corresponds to that of the i-th transmitting element. Let i be the position of the i-th transmitting element. Let be the position of the k-th receiving element, and c be the speed of sound of the ultrasonic wave.

[0115] Step S1062: Based on the second apodization coefficient and the second signal transmission delay, beamforming is performed on the second time-domain ultrasonic signal of the receiving array element corresponding to the transmitting array element to obtain the beamforming signal of the target imaging area.

[0116] Specifically, the beamforming signal of the target imaging region in step S1062 above is calculated using the following formula:

[0117]

[0118] in, Location in the target imaging region The beamforming signal, where N is the total number of elements in the ultrasonic array, w i,k tp is the second apodization coefficient corresponding to the i-th transmitting element for the k-th receiving element. i,k Location of the target in the imaging region The second signal transmission delay of the k-th receiving element corresponds to that of the i-th transmitting element, x. i,k Let t be the second time-domain ultrasonic signal of the k-th receiving element corresponding to the i-th transmitting element.

[0119] Step S1063: Envelope extraction and logarithmic compression are performed on the beamforming signal to obtain an ultrasound image.

[0120] The ultrasound imaging method provided in this embodiment performs delayed superposition beamforming on the second time-domain ultrasound signal corresponding to the transmitting element of the receiving element based on the second apodization coefficient and the second signal transmission delay of the receiving element. Therefore, it can improve the image quality of the ultrasound image in a dynamic focusing manner while reducing the sidelobe level of the beamforming signal, thereby further improving the image quality of the ultrasound image.

[0121] This embodiment also provides an ultrasound imaging device for implementing the above embodiments and preferred embodiments; details already described will not be repeated. As used below, the term "module" can refer to a combination of software and / or hardware that performs a predetermined function. Although the device described in the following embodiments is preferably implemented in software, hardware implementation, or a combination of software and hardware, is also possible and contemplated.

[0122] This embodiment provides an ultrasound imaging device, such as... Figure 5 As shown, it includes:

[0123] Signal acquisition module 201 is used to acquire the first time-domain ultrasonic signal received by the receiving element in the ultrasonic array;

[0124] The first transformation module 202 is used to perform Fourier transform on the first time-domain ultrasonic signal to obtain the first frequency-domain ultrasonic signal;

[0125] Parameter acquisition module 203 is used to acquire the first apodization coefficient and the first signal transmission delay of the transmitting array element in the ultrasonic array, wherein the transmitting array element corresponds to the receiving array element;

[0126] The reverse solving module 204 is used to process the first frequency domain ultrasonic signal based on the first apodization coefficient and the first signal transmission delay to obtain the second frequency domain ultrasonic signal of the receiving array element corresponding to the transmitting array element.

[0127] The second transformation module 205 is used to perform an inverse Fourier transform on the second frequency domain ultrasonic signal to obtain a second time domain ultrasonic signal.

[0128] The beamforming module 206 is used to perform beamforming based on the second time-domain ultrasound signal to obtain an ultrasound image.

[0129] In some optional implementations, the inverse solver module 204 includes:

[0130] An ultrasound matrix construction unit is used to construct a first ultrasound signal matrix using the first frequency domain ultrasound signal corresponding to the receiving array element as the element;

[0131] The weighting coefficient calculation unit is used to calculate the signal weighting coefficient of the transmitting array element based on the first apodization coefficient and the first signal transmission delay of the transmitting array element;

[0132] The coefficient matrix construction unit is used to construct a weighted coefficient matrix using the signal weighting coefficients of the transmitted array elements as elements;

[0133] The ultrasonic matrix solving unit is used to calculate the second ultrasonic signal matrix based on the first ultrasonic signal matrix and the weighting coefficient matrix.

[0134] The ultrasonic signal extraction unit is used to obtain the second frequency domain ultrasonic signal corresponding to the transmitting element from the second ultrasonic signal matrix. The second frequency domain ultrasonic signal corresponding to the transmitting element is an element of the second ultrasonic signal matrix.

[0135] In some optional implementations, the signal weighting coefficients of the weighting coefficient calculation unit are calculated using the following formula:

[0136]

[0137] Among them, c m,i Let a be the signal weighting coefficient of the i-th transmitting element during the m-th ultrasonic wave transmission. m,i Let σt be the first apodization coefficient of the i-th transmitting element during the m-th ultrasonic wave transmission. m,i ω represents the first signal transmission delay of the i-th transmitting element during the m-th ultrasonic wave transmission, where ω is the angular frequency and j is the imaginary number.

[0138] In some alternative implementations, the ultrasonic matrix solving unit includes:

[0139] The information acquisition subunit is used to acquire the number of rows and columns of the first ultrasound signal matrix or the weighting coefficient matrix;

[0140] The matrix solving sub-unit is used to calculate the second ultrasound signal matrix based on the relationship between the number of rows and columns, using the first ultrasound signal matrix and the weighting coefficient matrix.

[0141] In some alternative implementations, the matrix solving subunit is specifically used for:

[0142] When the number of rows is greater than or equal to the number of columns, the first ultrasonic signal matrix and the weighting coefficient matrix are calculated based on the least squares method or regularization optimization algorithm to obtain the second ultrasonic signal matrix;

[0143] When the number of rows is less than the number of columns, the first ultrasound signal matrix and the weighting coefficient matrix are calculated based on norm minimization to obtain the second ultrasound signal matrix.

[0144] In some alternative implementations, the beamforming module 206 includes:

[0145] The information acquisition unit is used to acquire the second apodization coefficient and the second signal transmission delay of the receiving array element corresponding to the transmitting array element;

[0146] The beamforming unit is used to perform beamforming on the second time-domain ultrasonic signal of the receiving array element corresponding to the transmitting array element based on the second apodization coefficient and the second signal transmission delay, so as to obtain the beamforming signal of the target imaging area.

[0147] The image generation unit is used to extract the envelope and logarithmically compress the beamforming signal to obtain an ultrasound image.

[0148] In some optional implementations, the beamforming signal of the target imaging region of the beamforming unit is calculated using the following formula:

[0149]

[0150] in, Location in the target imaging region The beamforming signal, where N is the total number of elements in the ultrasonic array, w i,k tp is the second apodization coefficient corresponding to the i-th transmitting element for the k-th receiving element. i,k Location of the target in the imaging region The second signal transmission delay of the k-th receiving element corresponds to that of the i-th transmitting element, x. i,kLet t be the second time-domain ultrasonic signal of the k-th receiving element corresponding to the i-th transmitting element.

[0151] Further functional descriptions of the above modules and units are the same as those in the corresponding embodiments described above, and will not be repeated here.

[0152] In this embodiment, the ultrasound imaging device is presented in the form of a functional unit. Here, a unit refers to an ASIC (Application Specific Integrated Circuit) circuit, a processor and memory that execute one or more software or fixed programs, and / or other devices that can provide the above functions.

[0153] This invention also provides a computer device having the above-described features. Figure 5 The ultrasound imaging device shown.

[0154] Please see Figure 6 , Figure 6 This is a schematic diagram of the structure of a computer device provided in an optional embodiment of the present invention, such as... Figure 6 As shown, the computer device includes one or more processors 10, memory 20, and interfaces for connecting the components, including high-speed interfaces and low-speed interfaces. The components communicate with each other via different buses and can be mounted on a common motherboard or otherwise installed as needed. The processors can process instructions executed within the computer device, including instructions stored in or on memory to display graphical information of a GUI on external input / output devices (such as display devices coupled to the interfaces). In some alternative implementations, multiple processors and / or multiple buses can be used with multiple memories and multiple memory modules, if desired. Similarly, multiple computer devices can be connected, each providing some of the necessary operations (e.g., as a server array, a group of blade servers, or a multiprocessor system). Figure 6 Take a processor 10 as an example.

[0155] Processor 10 may be a central processing unit, a network processor, or a combination thereof. Processor 10 may further include a hardware chip. The hardware chip may be an application-specific integrated circuit (ASIC), a programmable logic device (PLD), or a combination thereof. The programmable logic device may be a complex programmable logic device (CAMP), a field-programmable gate array (FPGA), a general-purpose array logic (GDA), or any combination thereof.

[0156] The memory 20 stores instructions executable by at least one processor 10 to cause at least one processor 10 to perform the method shown in the above embodiments.

[0157] The memory 20 may include a program storage area and a data storage area. The program storage area may store the operating system and applications required for at least one function; the data storage area may store data created based on the use of the computer device. Furthermore, the memory 20 may include high-speed random access memory and may also include non-transitory memory, such as at least one disk storage device, flash memory device, or other non-transitory solid-state storage device. In some alternative embodiments, the memory 20 may optionally include memory remotely located relative to the processor 10, and these remote memories may be connected to the computer device via a network. Examples of such networks include, but are not limited to, the Internet, intranets, local area networks, mobile communication networks, and combinations thereof.

[0158] The memory 20 may include volatile memory, such as random access memory; the memory may also include non-volatile memory, such as flash memory, hard disk or solid-state drive; the memory 20 may also include a combination of the above types of memory.

[0159] The computer device also includes an input device 30 and an output device 40. The processor 10, memory 20, input device 30, and output device 40 can be connected via a bus or other means. Figure 6 Taking the example of a connection between China and Israel via a bus.

[0160] Input device 30 can receive input numerical or character information, and generate key signal inputs related to user settings and function control of the computer device, such as a touchscreen, keypad, mouse, trackpad, touchpad, joystick, one or more mouse buttons, trackball, joystick, etc. Output device 40 may include display devices, auxiliary lighting devices (e.g., LEDs), and haptic feedback devices (e.g., vibration motors). The aforementioned display devices include, but are not limited to, liquid crystal displays, light-emitting diodes, displays, and plasma displays. In some alternative embodiments, the display device may be a touchscreen.

[0161] This invention also provides a computer-readable storage medium. The methods described above according to embodiments of the invention can be implemented in hardware or firmware, or implemented as computer code that can be recorded on a storage medium, or implemented as computer code downloaded via a network and originally stored on a remote storage medium or a non-transitory machine-readable storage medium and then stored on a local storage medium. Thus, the methods described herein can be processed by software stored on a storage medium using a general-purpose computer, a dedicated processor, or programmable or dedicated hardware. The storage medium can be a magnetic disk, optical disk, read-only memory, random access memory, flash memory, hard disk, or solid-state drive, etc.; further, the storage medium can also include combinations of the above types of memory. It is understood that computers, processors, microprocessor controllers, or programmable hardware include storage components capable of storing or receiving software or computer code, which, when accessed and executed by the computer, processor, or hardware, implements the methods shown in the above embodiments.

[0162] Although embodiments of the invention have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the invention, and such modifications and variations all fall within the scope defined by the appended claims.

Claims

1. An ultrasound imaging method, characterized in that, The method includes: Acquire the first time-domain ultrasonic signal received by the receiving element in the ultrasonic array; Perform a Fourier transform on the first time-domain ultrasonic signal to obtain the first frequency-domain ultrasonic signal; Obtain the first apodization coefficient and the first signal transmission delay of the transmitting element in the ultrasonic array; Based on the first apodization coefficient and the first signal transmission delay, the first frequency domain ultrasonic signal is processed to obtain the second frequency domain ultrasonic signal of the receiving array element corresponding to the transmitting array element. Perform an inverse Fourier transform on the second frequency domain ultrasonic signal to obtain the second time domain ultrasonic signal; Beamforming is performed based on the second time-domain ultrasonic signal to obtain an ultrasonic image; Specifically, beamforming is performed based on the second time-domain ultrasonic signal corresponding to the transmitting element of the receiving array element to obtain an ultrasonic image, including: Obtain the second apodization coefficient and the second signal transmission delay of the receiving array element corresponding to the transmitting array element; Based on the second apodization coefficient and the second signal transmission delay, beamforming is performed on the second time-domain ultrasonic signal of the receiving array element corresponding to the transmitting array element to obtain the beamforming signal of the target imaging region. Envelope extraction and logarithmic compression are performed on the beamforming signal to obtain an ultrasound image; The beamforming signal of the target imaging region is calculated using the following formula: ； in, Location in the target imaging region The beamforming signal, where N is the total number of elements in the ultrasonic array. The second apodization coefficient of the k-th receiving element corresponds to the i-th transmitting element. Location of the target imaging region The second signal transmission delay of the k-th receiving array element corresponds to that of the ith transmitting array element. The second time-domain ultrasonic signal of the k-th receiving array element corresponds to the i-th transmitting array element, where t is the time.

2. The method according to claim 1, characterized in that, The step of processing the first frequency domain ultrasonic signal based on the first apodization coefficient and the first signal transmission delay to obtain the second frequency domain ultrasonic signal corresponding to the transmitting array element for the receiving array element includes: A first ultrasonic signal matrix is ​​constructed using the first frequency domain ultrasonic signal corresponding to the receiving array element as elements; Based on the first apodization coefficient and the first signal transmission delay of the transmitting array element, the signal weighting coefficient of the transmitting array element is calculated; A weighting coefficient matrix is ​​constructed using the signal weighting coefficients of the aforementioned transmitting array elements. The second ultrasound signal matrix is ​​obtained by calculating based on the first ultrasound signal matrix and the weighting coefficient matrix. From the second ultrasonic signal matrix, the second frequency domain ultrasonic signal corresponding to the transmitting element of the receiving element is obtained, and the second frequency domain ultrasonic signal corresponding to the transmitting element of the receiving element is an element of the second ultrasonic signal matrix.

3. The method according to claim 2, characterized in that, The signal weighting coefficients are calculated using the following formula: ； in, is the signal weighting coefficient of the i-th transmitting element during the m-th ultrasonic wave transmission. Let be the first apodization coefficient of the i-th transmitting element during the m-th ultrasonic wave transmission. The first signal transmission delay of the i-th transmitting element during the m-th ultrasonic wave transmission. ω is the angular frequency, and j is the imaginary number.

4. The method according to claim 2, characterized in that, The step of calculating the second ultrasound signal matrix based on the first ultrasound signal matrix and the weighting coefficient matrix includes: Obtain the number of rows and columns of the first ultrasound signal matrix or the weighting coefficient matrix; Based on the relationship between the number of rows and the number of columns, the first ultrasonic signal matrix and the weighting coefficient matrix are calculated to obtain the second ultrasonic signal matrix.

5. The method according to claim 4, characterized in that, The step of calculating the second ultrasound signal matrix based on the relationship between the number of rows and the number of columns, using the first ultrasound signal matrix and the weighting coefficient matrix, includes: When the number of rows is greater than or equal to the number of columns, the first ultrasonic signal matrix and the weighting coefficient matrix are calculated based on the least squares method or regularization optimization algorithm to obtain the second ultrasonic signal matrix; When the number of rows is less than the number of columns, the first ultrasound signal matrix and the weighting coefficient matrix are calculated based on norm minimization to obtain the second ultrasound signal matrix.

6. An ultrasonic imaging device, characterized in that, The device includes: The signal acquisition module is used to acquire the first time-domain ultrasonic signal received by the receiving element in the ultrasonic array; The first transformation module is used to perform a Fourier transform on the first time-domain ultrasonic signal to obtain a first frequency-domain ultrasonic signal; The parameter acquisition module is used to acquire the first apodization coefficient and the first signal transmission delay of the transmitting array element in the ultrasonic array; The reverse solving module is used to process the first frequency domain ultrasonic signal based on the first apodization coefficient and the first signal transmission delay to obtain the second frequency domain ultrasonic signal of the receiving array element corresponding to the transmitting array element. The second transformation module is used to perform an inverse Fourier transform on the second frequency domain ultrasonic signal to obtain a second time domain ultrasonic signal. A beamforming module is used to perform beamforming based on the second time-domain ultrasound signal to obtain an ultrasound image; The beamforming module includes: The information acquisition unit is used to acquire the second apodization coefficient and the second signal transmission delay of the receiving array element corresponding to the transmitting array element; The beamforming unit is used to perform beamforming on the second time-domain ultrasonic signal of the receiving array element corresponding to the transmitting array element based on the second apodization coefficient and the second signal transmission delay, so as to obtain the beamforming signal of the target imaging area. The image generation unit is used to extract the envelope and logarithmically compress the beamforming signal to obtain an ultrasound image. The beamforming signal of the target imaging region of the beamforming unit is calculated using the following formula: ； in, Location in the target imaging region The beamforming signal, where N is the total number of elements in the ultrasonic array. The second apodization coefficient of the k-th receiving element corresponds to the i-th transmitting element. Location of the target imaging region The second signal transmission delay of the k-th receiving array element corresponds to that of the ith transmitting array element. The second time-domain ultrasonic signal of the k-th receiving array element corresponds to the i-th transmitting array element, where t is the time.

7. A computer device, characterized in that, include: A memory and a processor are communicatively connected, the memory storing computer instructions, and the processor executing the computer instructions to perform the ultrasound imaging method of any one of claims 1 to 5.

8. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores computer instructions for causing the computer to perform the ultrasound imaging method according to any one of claims 1 to 5.

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