CN101645167A - Method and device for frame correlation coefficient control and frame correlation processing, and ultrasonic imaging system - Google Patents

Abstract

The invention discloses a method and a device for frame correlation coefficient control and frame correlation processing, and an ultrasonic imaging system. The method for the frame correlation coefficient control comprises the following steps: comparing the amplitude-frequency response of a current filter at a current imaging frame rate with the amplitude-frequency response of a reference filter at a reference imaging frame rate; acquiring the difference between the amplitude-frequency response of the current filter and the amplitude-frequency response of the reference filter in an overlappedfrequency band; and judging the frame correlation coefficient corresponding to the amplitude-frequency response of the current filter when the difference is minimum to be the best frame correlation coefficient corresponding to the current imaging frame rate. The method and the device for the frame correlation coefficient control and the frame correlation processing can obtain the frame correlationcoefficient accurately, make the frame correlation processing results of images very close to each other when the imaging frame rate changes dramatically, ensure the noise filtering effect of an ultrasonic image, and improve the signal-to-noise ratio of the image effectively.

Description

Frame correlation coefficient control and frame correlation processing method, device and ultrasonic image-forming system

Technical field

The present invention relates to the optimisation technique field of ultrasonoscopy time domain smothing filtering coefficient in the ultrasonic system, in particular, a kind of control method of frame correlation coefficient and device thereof and the frame correlation processing method and the ultrasonic image-forming system that utilize this method.

Background technology

Ultrasonoscopy is owing to exist bigger circuit noise and spot (Speckle) noise (wherein, speckle noise is owing to the scattered signal coherence stack of taking measurements greatly less than the particle of ultrasound wave wavelength forms, this is intrinsic problem in the ultrasonoscopy system), so need smoothing processing, to improve the signal to noise ratio (S/N ratio) of image through some time domains and spatial domain.Wherein, the smoothing processing of time domain also claims the frame relevant treatment usually.The mode that frame relevant treatment commonly used adopts previous frame output image and present frame image to do weighted sum realizes that be a kind of simple recursive filtering method, it can be expressed as:

y(t)＝ay(t-1)+(1-a)x(t) (1)

Wherein, the image of y (t) for exporting after the present frame frame relevant treatment, x (t) is the present frame image, and y (t-1) is the output image of previous frame, and a is a frame correlation coefficient.

In fact, the frame relevant treatment belongs to a kind of filtering method, and it can be described as a first order IIR (Infinite Impulse Response) digital filter in the signal Processing field, and the transfer function H (z) in this digital filter Z territory can be expressed as:

$H\left(z\right)=\frac{1-a}{1-{\mathrm{az}}^{-1}}---\left(2\right)$

With z=exp{j2 π f ' }, the above-mentioned H of substitution (z) promptly obtains the frequency response H (f ') of wave filter.Generally, only consider the amplitude-frequency response of this wave filter during the frame relevant treatment, i.e. the amplitude of said frequencies response | and H (f ') |, wherein, f ' is the normalization numerical frequency.

According to the frequency response of above-mentioned wave filter as can be known, this wave filter is a low-pass filter, because the circuit noise of different frame is normally independent, and the speckle noise of different frame moving owing to tissue or probe, cause the speckle noise of different frame also to have more weak correlativity, and the image of the tissue of different frame or blood flow has stronger correlativity, therefore can effectively suppress noise in the image by this wave filter, and the enhancing useful signal, thereby improve the contrast resolution of image.Can realize in various degree squelch by different frame correlation coefficient a is set, along with the increase of frame correlation coefficient a, noise suppression effect is remarkable more, but also causes the fuzzy of motor tissue image easily.Same frame correlation coefficient a shows different squelch and motor tissue blur effect under different image imaging frame per second, as when imaging frame rate is higher, bigger frame correlation coefficient a is set then can reduces picture noise effectively, and can not cause motion blur, but when imaging frame rate was lower, same frame correlation coefficient a then can cause tangible motion blur.

In the existing compuscan, normal frame correlation coefficient a is set to the exponential function of imaging frame rate, and it specifically is expressed as

a＝exp{-1/k×Fr} (3)

Wherein, k is the relevant control coefrficient of frame, and Fr is an imaging frame rate.As seen, along with the reduction of imaging frame rate Fr, frame correlation coefficient a also decreases, and has improved the imaging frame rate Fr influence level and smooth to the image time domain to a certain extent.

The frame correlation coefficient a that formula (3) is represented is updated in the transport function in the represented digital filter Z territory of aforementioned formula (2),

Wherein, $\begin{array}{c}z=\exp \left\{\mathrm{<figure-callout\; id="2"\; label="j"\; filenames="A2008101427870026H1.png,A2008101427870027H2.png"\; state="\{\{state\}\}">j</figure-callout>}2\mathrm{\&pi;}{f}^{\&prime;}\right\}\\ f^{\&prime;}=f/\mathrm{Fr},f\&Element;[0,\mathrm{Fr}/2]\end{array},$ Can obtain corresponding wave filter amplitude-frequency response | H (f) |.As an example, under the different imaging frame rates, the relevant pairing wave filter amplitude-frequency response of control coefrficient k of same number of frames as shown in Figure 1, it has provided the relevant control coefrficient k of frame respectively is 0.02, frame per second is 15Hz, 30Hz is under the situation of 45Hz and 60Hz, by four amplitude-frequency responses of said method acquisition.The frequency range of the amplitude-frequency response correspondence of real coefficient digital filter is zero to 1/2nd of current imaging frame rate, i.e. f=0～Fr _t/ 2, as seen from Figure 1, amplitude-frequency response under the different frame per second is along with the wave filter that reduction obtains of the frame per second inhibition ability to high frequency noise also decreases, the noise suppression effect difference also more greatly when frame per second changed more greatly, therefore when frame per second changes greatly, the high frequency attenuation of frame relevant treatment obviously descends, thereby has reduced the relevant inhibiting effect to speckle noise and circuit noise of frame.

According to above-mentioned analysis, when imaging frame rate Fr variation is little, adopt above-mentioned formula (3) simply to find the solution frame correlation coefficient a when carrying out the frame relevant treatment, its frame relevant effect is close, but, when imaging frame rate Fr changes greatly, the situation that the noise suppression effect variation just may occur, switch to the color flow angiography pattern such as compuscan from organizing gray scale (B-mode) imaging pattern, be generally image-to-frame ratio Fr and drop to several frames from tens frames, organize this moment the noise of gray level image to increase suddenly, carry out the frame relevant treatment if at this moment also adopt above-mentioned formula (3) simply to find the solution frame correlation coefficient a, just can't guarantee the frame relevant effect of image, image fault can occur, reduce the filtration result of picture noise.

As seen, also there is certain drawback in the method that obtains frame correlation coefficient a in the prior art, needs to improve further.

Summary of the invention

The frame correlation processing method and the ultrasonic image-forming system that the object of the present invention is to provide a kind of control method and device thereof of frame correlation coefficient and utilize this method, it can obtain frame correlation coefficient, and when imaging frame rate alters a great deal, the frame correlation coefficient that uses the present invention to obtain can make the frame relevant treatment result of image very approaching, guarantee the ultrasonic image noise filtration result, and the signal to noise ratio (S/N ratio) of effectively improving image.

To achieve these goals, the present invention adopts following technical scheme:

The invention provides a kind of control method of frame correlation coefficient, described method comprises: the reference filter amplitude-frequency response under a pre-filter amplitude-frequency response and a benchmark imaging frame rate under A, the more current imaging frame rate obtains described when pre-filter amplitude-frequency response and the difference of reference filter amplitude-frequency response in overlapping bands; B, with described difference be hour when the pairing frame correlation coefficient of pre-filter amplitude-frequency response, be judged to be the pairing optimum frame related coefficient of current imaging frame rate.

Based on the above method, the present invention also provides a kind of frame correlation coefficient controller, and described controller comprises: first module is used for according to the frame correlation coefficient under the default benchmark imaging frame rate calculating benchmark imaging frame rate; Unit second, the frame correlation coefficient that is used for obtaining according to first module calculates the reference filter amplitude-frequency response; And Unit the 3rd, be used for more current imaging frame rate under when pre-filter amplitude-frequency response and the difference of described reference filter amplitude-frequency response in overlapping bands, that exports described difference and be hour works as the pairing frame correlation coefficient of pre-filter amplitude-frequency response.

Based on the above method, the present invention also provides a kind of ultrasonoscopy frame correlation processing method, said method comprising the steps of:

The reference filter amplitude-frequency response under a pre-filter amplitude-frequency response and a benchmark imaging frame rate under S1, the more current imaging frame rate obtains described when pre-filter amplitude-frequency response and the difference of reference filter amplitude-frequency response in overlapping bands;

S2, with described difference be hour when the pairing frame correlation coefficient of pre-filter amplitude-frequency response, be judged to be the pairing optimum frame related coefficient of current imaging frame rate;

The optimum frame related coefficient that S3, utilization obtain is carried out the frame related operation, the current frame image after obtaining to handle.

At said method, the present invention also provides a kind of ultrasonic image-forming system, and described system comprises: ultrasonoscopy processing module and the probe that is used to obtain ultrasonoscopy; Be provided with a frame correlation coefficient controller and a frame relevant treatment unit in the described ultrasonoscopy processing module, this controller comprises: first module is used for according to the frame correlation coefficient under the default benchmark imaging frame rate calculating benchmark imaging frame rate; Unit second, the frame correlation coefficient that is used for obtaining according to first module calculates the reference filter amplitude-frequency response; And Unit the 3rd, be used for more current imaging frame rate under when pre-filter amplitude-frequency response and the difference of described reference filter amplitude-frequency response in overlapping bands, that exports described difference and be hour works as the pairing frame correlation coefficient of pre-filter amplitude-frequency response; Described frame relevant treatment unit is used to receive the frame correlation coefficient of described Unit the 3rd output, and utilizes this frame correlation coefficient to carry out the frame related operation, the current frame image after obtaining to handle.

In addition, the present invention also provides a kind of ultrasonic image-forming system, and described system comprises: ultrasonoscopy processing module and the probe that is used to obtain ultrasonoscopy; Be provided with a storage medium in the described ultrasonoscopy processing module, search a unit and a frame relevant treatment unit, described storage medium is preserved a relation table, this table record has optimum frame related coefficient under current imaging frame rate, the current imaging frame rate, and characterizes corresponding relation between the relevant control coefrficient three of frame of frame relevant effect, the difference minimum of reference filter amplitude-frequency response in overlapping bands under a pre-filter amplitude-frequency response and a benchmark imaging frame rate of described optimum frame related coefficient correspondence; Described frame relevant treatment unit links to each other with described storage medium by the described unit of searching, the described unit of searching is used for searching described relation table and current imaging frame rate and the corresponding optimum frame related coefficient of the relevant control coefrficient of present frame, and this optimum frame related coefficient is sent in the described frame relevant treatment unit; Described frame relevant treatment unit is used to utilize described optimum frame related coefficient to carry out the frame related operation, the current frame image after obtaining to handle.

From technique scheme as can be known, the present invention is by setting up the minimum difference principle of reference filter amplitude-frequency response in overlapping bands under a pre-filter amplitude-frequency response and a benchmark imaging frame rate, select best frame correlation coefficient, frame relevant treatment in order to ultrasonoscopy, in terms of existing technologies, the present invention adopts the frame correlation coefficient of reverse thinking from the effect calculating optimum that will obtain, thereby can obtain the frame correlation coefficient more suitable than prior art, optimize ultrasonoscopy time domain smothing filtering coefficient, feasible frame correlation processing method and the ultrasonic image-forming system thereof that utilizes this method, has better filter effect, and when imaging frame rate alters a great deal, also can guarantee the display effect of image, and make the frame relevant treatment result of image very approaching.

Description of drawings

Fig. 1 is the wave filter amplitude-frequency response characteristic figure that prior art obtains;

Fig. 2 is the process flow diagram of frame correlation coefficient control method of the present invention;

Fig. 3 is the method flow diagram of the embodiment of the invention 1 to 3;

Fig. 4 be the present invention to utilize the relevant control coefrficient k of the frame that method obtained of embodiment 1 be 0.02, frame per second is followed successively by the pairing amplitude-frequency response characteristic figure of 15Hz, 30Hz, 45Hz and 60Hz;

Fig. 5 be the present invention to utilize the relevant control coefrficient k of the frame that method obtained of embodiment 4 be 0.02, frame per second is followed successively by the pairing amplitude-frequency response characteristic figure of 15Hz, 30Hz, 45Hz and 60Hz;

Fig. 6 is the structural representation of frame correlation coefficient controller of the present invention;

Fig. 7 is the inner structure synoptic diagram of Unit the 3rd among Fig. 6;

Fig. 8 is the structural representation that relates to image processing section in a kind of ultrasonic image-forming system provided by the invention;

Fig. 9 is the structural representation that relates to image processing section in the another kind of ultrasonic image-forming system provided by the invention.

Embodiment

For when imaging frame rate alters a great deal, can guarantee that also the frame relevant treatment result of image is very approaching, the present invention has provided a kind of control method of frame correlation coefficient, its accurate Calculation the frame correlation coefficient under the current frame rate.As shown in Figure 2, the main process of the given frame correlation coefficient control method of the present invention is as follows:

At first, more current imaging frame rate Fr _tUnder when the pre-filter amplitude-frequency response | H (f) | with a benchmark imaging frame rate Fr ₀Under the reference filter amplitude-frequency response | H ₀(f) |, obtain when the pre-filter amplitude-frequency response | H (f) | with the reference filter amplitude-frequency response | H ₀(f) | the difference E in overlapping bands, promptly E=F (| H (f) |, | H ₀(f) |), F represents difference function;

Then, with described difference E be hour when the pre-filter amplitude-frequency response | H (f) | pairing frame correlation coefficient is judged to be the pairing optimum frame related coefficient of current imaging frame rate Frt.

As seen, the present invention on the basis of existing technology, provided a kind of new frame correlation coefficient computing method, this method has defined a minimum difference principle, and it calculates the frame correlation coefficient that obtains and makes when the pre-filter amplitude-frequency response | H (f) | with the reference filter amplitude-frequency response | H ₀(f) | difference minimum that is to say this moment in overlapping bands, and wave filter is at current imaging frame rate Fr _tWith benchmark imaging frame rate Fr ₀Has close amplitude-frequency response characteristic down.Only guarantee when Flame Image Process that the wave filter amplitude-frequency response under the different imaging frame rates all approaches the benchmark amplitude-frequency response, could guarantee in overlapping bands, to have close amplitude-frequency response characteristic between the wave filter amplitude-frequency response under the different imaging frame rates, thereby effectively guarantee the smoothing processing effect and the Noise Suppression effect of Flame Image Process.

As shown in Figure 2, frame correlation coefficient control method of the present invention need be set the frequency Fr of a benchmark ₀Frame correlation coefficient a (Fr under (as real-time imaging frame rate, i.e. 50HZ or 60H) ₀).This frame correlation coefficient a (Fr ₀) can be according to aforementioned formula (3), determine to calculate the relevant gear of frame of the corresponding ultrasonic image-forming system of the relevant control coefrficient k of frame, the frame relevant effect of its token image by selecting the relevant control coefrficient k of frame.With frame correlation coefficient a (Fr ₀) corresponding amplitude-frequency response | H ₀(f) | as the reference function, as current imaging frame rate Fr _tGreater than Fr ₀The time, smoothing processing requires current imaging frame rate Fr _tFollowing frame correlation coefficient a (Fr _t) corresponding wave filter amplitude-frequency response | H (f) | at 0～Fr ₀Has close response in/2 the scope; And, as current imaging frame rate Fr _tLess than Fr ₀The time, require current imaging frame rate Fr _tFollowing frame correlation coefficient a (Fr _t) corresponding wave filter amplitude-frequency response | H (f) | at 0～Fr _tHas close response in/2 scopes.As seen, the overlapping bands of two wave filter amplitude-frequency responses can be expressed as [0, min (Fr ₀/ 2, Fr _t/ 2)], by setting current imaging frame rate Fr _tUnder frame correlation coefficient a (Fr _t) make corresponding wave filter amplitude-frequency response frequency band [0, min (Fr ₀/ 2, Fr _t/ 2) close], realize the smoothing processing of image, thereby guarantee under imaging frame rate variation situation greatly, also can obtain the frame relevant treatment effect of basically identical.

The control method of frame correlation coefficient shown in Figure 2, according to difference function E=F (| H (f) |, | H ₀(f) |) the mode of setting up, can have multiple implementation, below be elaborated at several modes commonly used.

Embodiment 1: as shown in Figure 3, the E of difference described in the present embodiment is: the reference filter amplitude-frequency response | H ₀(f) | with when the pre-filter amplitude-frequency response | H (f) | difference overlapping bands [0, min (Fr ₀/ 2, Fr _t/ 2)] Nei quadratic sum, promptly

$E=\underset{f\&Element;[0,\min ({\mathrm{Fr}}_0/2,{\mathrm{Fr}}_t/2)]}{\mathrm{\&Sigma;}}{\left(\right|H\left(f\right)|-|H_0\left(f\right)\left|\right)}^2.---\left(4\right)$

As shown in Figure 3, the detailed process of present embodiment is as follows:

Step 200, predefined benchmark imaging frame rate Fr ₀, the benchmark imaging frame rate Fr here ₀Be the real time imagery frame per second, as 50HZ or 60HZ.

Step 210 is with predefined benchmark imaging frame rate Fr ₀, calculate its frame correlation coefficient a (Fr in the substitution aforementioned formula (3) ₀), the result is as follows:

a(Fr ₀)＝exp{-1/k×Fr ₀}

Wherein, k is the relevant control coefrficient of frame, and it is determined that by experience this k value has determined the frame relevant effect of image, and corresponding with the relevant gear of frame of supersonic sounding instrument, and its span is 0～1.

Step 220 obtains frame correlation coefficient a (Fr with aforementioned calculation ₀) be input in the transfer function model of digital filter the benchmark amplitude-frequency response of calculating filter | H ₀(f) |, its corresponding frequency band range is 0～Fr ₀/ 2.

Here, the transfer function model that belongs to single order infinite impulse response (InfiniteImpulse Response) digital filter Z territory with the transfer function model of digital filter is an example, describes the benchmark amplitude-frequency response in detail | H ₀(f) | computation process.

According to aforementioned formula (2)

$H\left(z\right)=\frac{1-a}{1-{\mathrm{az}}^{-1}}$

With z=exp{j2 π f ' }, f '=f/Fr, f ∈ [0, Fr/2] promptly obtains the frequency response H (f) of wave filter, the amplitude-frequency response of its amplitude correspondence among the above-mentioned H of substitution (z) | H (f) | expression formula is:

$\left|H\left(f\right)\right|=\frac{1-a}{\sqrt{{(1-a\cos (2\mathrm{\&pi;f}/\mathrm{Fr}))}^2+a^2{\sin }^2(2\mathrm{\&pi;f}/\mathrm{Fr})}}---\left(5\right)$

Wherein, f ' is the normalization numerical frequency, and f is an actual frequency, and Fr is an imaging frame rate.

According to above-mentioned formula, with frame correlation coefficient a (Fr ₀), benchmark imaging frame rate Fr ₀Be updated in the above-mentioned formula (5), can obtain about benchmark imaging frame rate Fr ₀Under the benchmark amplitude-frequency response | H ₀(f) | function expression.

Step 230 is set current imaging frame rate Fr _tUnder N candidate frame related coefficient a` (Fr <sub>t</sub>), wherein N is the natural number greater than 2; And then respectively with this N candidate frame related coefficient a` (Fr _t) be input in the transfer function model (transfer function model in the single order infinite impulse response digital filter Z territory shown in above-mentioned formula (5)) of digital filter, calculate each candidate frame related coefficient a` (Fr _t) the corresponding current amplitude-frequency response of wave filter | H (f) |, its corresponding frequency band range is 0～Fr _t/ 2.

The N here candidate frame related coefficient a` (Fr _t) can rule of thumb come to determine, also can come in such a way to determine:

The first step is calculated current imaging frame rate Fr according to conventional method _tUnder frame correlation coefficient estimated value a (Fr _t), for example, in the exponential function with frame correlation coefficient shown in the current imaging frame rate Frt substitution aforementioned formula (3) and imaging frame rate, calculate its frame correlation coefficient estimated value a (Fr _t), the result is as follows:

a(Fr _t)＝exp{-1/k×Fr _t}。

From above-mentioned formula as can be seen, the candidate frame related coefficient a` (Fr of the different corresponding different frame relevant effect of the relevant control coefrficient k of frame _t), calculating this estimated value a (Fr _t) time, its k value can be with reference to selected value in the step 210.

Second step is at described estimated value a (Fr _t) near N of selection value as candidate frame related coefficient a` (Fr <sub>t</sub>), this N is the natural number more than or equal to 2.For example, with a (Fr <sub>t</sub>) value is for getting 100 numerical value in the interval at center, as candidate frame related coefficient a` (Fr _t).

Step 240, at the benchmark amplitude-frequency response | H ₀(f) | and current amplitude-frequency response | H (f) | overlapping bands in, more described respectively benchmark amplitude-frequency response | H ₀(f) | with each candidate frame related coefficient a` (Fr <sub>t</sub>) the current amplitude-frequency response of pairing wave filter | H (f) | between difference E, promptly according to above-mentioned formula (4) calculate [0, min (Fr <sub>0</sub>/ 2, Fr <sub>t</sub>/ 2) each a` (Fr] _t) pairing E value, according to the minimum principle of difference, from each candidate frame related coefficient a` (Fr <sub>t</sub>) the middle current imaging frame rate Fr of conduct that selects an optimum <sub>t</sub>Under optimum frame related coefficient a (Fr <sub>t</sub>), be about to the E value hour | H (f) | pairing candidate frame related coefficient a` (Fr _t) as current imaging frame rate Fr _tUnder optimum frame related coefficient a (Fr _t).

The present embodiment filter coefficient is according to when the pre-filter amplitude-frequency response | H (f) | frequency band [0, min (Fr ₀/ 2, Fr _t/ 2)] interior and a (Fr ₀) corresponding wave filter amplitude-frequency response | H ₀(f) | have that minimum square error principle determines.As seen, the amplitude-frequency response function is the nonlinear function of frame correlation coefficient a and frequency f, current imaging frame rate Fr _tFollowing corresponding frame correlation coefficient a (Fr _t) can pass through numerical methods of solving.The amplitude-frequency response that utilizes the frame correlation coefficient correspondence under the different imaging frame rates that the implementation of present embodiment obtains as shown in Figure 4.As seen from Figure 4, the amplitude-frequency response in overlapping bands, under the different frame per second is also very close, has guaranteed that the fog-level of different frame per second situation undertissue motion is close, and noise also had suppresses effect preferably.

The account form of certain above-mentioned difference has more than a kind of, asks for an interview following embodiment.

Embodiment 2: the difference of present embodiment and embodiment 1 is that in step 240, the E of difference described in the present embodiment is: the reference filter amplitude-frequency response | H ₀(f) | with when the pre-filter amplitude-frequency response | H (f) | difference overlapping bands [0, min (Fr ₀/ 2, Fr _t/ 2)] Nei absolute value sum, promptly

$E=\underset{f\&Element;[0,\min ({\mathrm{<figure-callout\; id="0"\; label="Fr"\; filenames="A2008101427870026H1.png,A2008101427870027H2.png"\; state="\{\{state\}\}">Fr</figure-callout>}}_0/2,{\mathrm{Fr}}_t/2)]}{\mathrm{\&Sigma;}}\left|\right|H\left(f\right)|-|H_0\left(f\right)\left|\right|.---\left(6\right)$

By the size of this difference value E relatively, with this difference value E be hour when the pre-filter amplitude-frequency response | H (f) | pairing candidate frame related coefficient a` (Fr _t) be defined as current imaging frame rate Fr _tUnder optimum frame related coefficient a (Fr _t).All the other steps of present embodiment are identical with embodiment 1.The present embodiment filter coefficient is according to when the pre-filter amplitude-frequency response | H (f) | frequency band [0, min (Fr ₀/ 2, Fr _t/ 2)] interior and a (Fr ₀) corresponding wave filter amplitude-frequency response | H ₀(f) | have that the principle of minimum Error Absolute Value sum determines.With embodiment 1, current frame rate Fr _tFollowing corresponding frame correlation coefficient a (Fr _t) can find the solution by numerical method.Utilize amplitude-frequency response and the Fig. 4 of the frame correlation coefficient correspondence under the different imaging frame rates that the implementation of present embodiment obtains similar.

Embodiment 3: the difference of present embodiment and embodiment 1 is that in step 240, the E of difference described in the present embodiment is: overlapping bands [0, min (Fr ₀/ 2, Fr _t/ 2)], at a setpoint frequency f ₁Following reference filter amplitude-frequency response | H ₀(f) | with when the pre-filter amplitude-frequency response | H (f) | the absolute value of difference, promptly

E＝||H(f ₁)|-|H ₀(f ₁)||， (7)

Wherein, setpoint frequency f ₁For above-mentioned overlapping bands (0, min (Fr ₀/ 2, Fr _t/ 2) the arbitrary value] except that zero.By setting a frequency f ₁, calculate according to above-mentioned formula (7) then and the size of comparing difference value E, with this difference value E be hour work as the pre-filter amplitude-frequency response | H (f) | pairing candidate frame related coefficient a` (Fr _t) be defined as current imaging frame rate Fr _tUnder optimum frame related coefficient a (Fr _t).All the other steps of present embodiment are identical with embodiment 1.The present embodiment filter coefficient be according to frequency band [0, min (Fr ₀/ 2, Fr _t/ 2) work as the pre-filter amplitude-frequency response] | H (f) | with a (Fr ₀) corresponding wave filter amplitude-frequency response | H ₀(f) the minimum principle of the absolute value of | difference is determined.With embodiment 1, current frame rate Fr _tFollowing corresponding frame correlation coefficient a (Fr _t) can find the solution by numerical method.

Embodiment 4: the difference of present embodiment and embodiment 3 is that in step 240, difference described in the present embodiment is meant for minimum situation: at a setpoint frequency f ₁Following reference filter amplitude-frequency response | H ₀(f) | with when the pre-filter amplitude-frequency response | H (f) | difference be zero, promptly

E＝|H(f ₁)|-|H ₀(f ₁)|＝0， (8)

Just, at setpoint frequency f ₁On make | H ₀(f) |=H (f) |, this moment is when the pre-filter amplitude-frequency response | H (f) | and pairing candidate frame related coefficient a` (Fr _t) be judged as current imaging frame rate Fr _tUnder optimum frame related coefficient a (Fr _t), f wherein ₁=(0, min (Fr ₀/ 2, Fr _t/ 2)].All the other steps of present embodiment are identical with embodiment 3, and these all the other steps are meant except that step 230 setting candidate frame related coefficient, reach the step relevant with the candidate frame related coefficient.

This example is by setting a (Fr _t) make when the pre-filter amplitude-frequency response | H (f) | in certain predefined frequency f ₁(f ₁Be not equal to 0) on have and the reference filter amplitude-frequency response | H ₀(f) | identical numerical value, even | H ₀(f)=| H (f) |, wherein, frequency f ₁Optimum may be selected to be min (Fr ₀/ 2, Fr _t/ 2), i.e. Fr ₀/ 2 and Fr _t/ 2 smallers among both.And, by with a (Fr ₀), f ₁Substitution amplitude-frequency response function | H ₀(f) |, and with f1 substitution amplitude-frequency response function | H (f) |, find the solution above-mentioned equation (8) by parsing and promptly obtain current imaging frame rate Fr _tUnder optimum frame related coefficient a (Fr _t).

Present embodiment belongs to a kind of special circumstances among the embodiment 3, after the parsing of employing present embodiment is found the solution, can simplify above-mentioned computation rule as shown in Figure 3, as reducing step of setting the candidate frame related coefficient or the like, because above-mentioned formula (8) is a definite equation, it can directly calculate optimum frame related coefficient a (Fr _t).Present embodiment is for embodiment 1 to 3, and the implementation of present embodiment can be by imaging system software according to current imaging frame rate Fr because calculated amount is less _tThe relevant control coefrficient k of the frame of relevant gear correspondence with frame calculates in real time and obtains current imaging frame rate Fr _tFrame correlation coefficient a (Fr _t).The amplitude-frequency response that utilizes the frame correlation coefficient correspondence under the different imaging frame rates that the implementation of present embodiment obtains as shown in Figure 5.As seen from Figure 5, amplitude-frequency response is also very close in overlapping bands, has guaranteed that the fog-level of different frame per second situation undertissue motion is close, and noise also had suppresses effect preferably.

Embodiment 5: in order to simplify calculation procedure, present embodiment also increases the following table step of building on the basis of the foregoing description 1,2,3 or 4:

Determined optimum frame related coefficient a (Fr under the current imaging frame rate Frt by embodiment 1,2,3 or 4 _t) after, with this optimum frame related coefficient a (Fr _t) be stored in the relation table the current imaging frame rate Fr of this table record _t, current imaging frame rate Fr _tUnder optimum frame related coefficient a (Fr _t), and characterize corresponding relation between the relevant control coefrficient k three of frame of frame relevant effect;

Then, when realtime graphic is handled, can search described relation table, determine current imaging frame rate Fr in real time according to current imaging frame rate Frt and the relevant control coefrficient k of frame _tUnder optimum frame related coefficient a (Fr _t).The relation table about the optimum frame related coefficient that utilizes present embodiment to set up can be stored in the computer-readable recording medium.

Because the numerical methods of solving operand of the foregoing description 1 to 3 is bigger, so present embodiment is stored as a coefficient table by calculating the optimum frame related coefficient under the good different imaging frame rates in advance with these frame correlation coefficients.When needs are provided with different frame relevant effect, can be by change benchmark frame per second Fr ₀Under the relevant control coefrficient k of frame, obtain different | H ₀(f) |, numerical evaluation goes out corresponding different imaging frame rate Fr then _tUnder frame correlation coefficient a, thereby formed a two-dimentional coefficient table of different frame relevant effect and different imaging frame rates, will utilize the optimum frame related coefficient a (Fr under the current imaging frame rate that embodiment 1,2 or 3 solves then _t) add wherein, can obtain the above-mentioned relation table.Ultrasonic image-forming system is tabled look-up to the above-mentioned relation table according to the gear and the imaging frame rate of different frame relevant effect, can obtain the frame correlation coefficient under the current imaging frame rate.

The account form of common several species diversity has just been enumerated in above-mentioned analysis, and how the present invention calculates difference and unrestrictedly.Such as, according to saying that the difference mathematical model of above-mentioned each embodiment can be summarized, the mathematical model of difference E can be expressed as the reference filter amplitude-frequency response | H ₀(f) | with when the pre-filter amplitude-frequency response | H (f) | difference absolute value overlapping bands [0, min (Fr ₀/ 2, Fr _t/ 2)] Nei n power sum, promptly

$E=\underset{f\&Element;[0,\min ({\mathrm{<figure-callout\; id="0"\; label="Fr"\; filenames="A2008101427870026H1.png,A2008101427870027H2.png"\; state="\{\{state\}\}">Fr</figure-callout>}}_0/2,{\mathrm{Fr}}_t/2)]}{\mathrm{\&Sigma;}}{\left|\right|H\left(f\right)|-|H_0\left(f\right)\left|\right|}^n,---\left(9\right)$

Wherein, n is the natural number greater than zero.In the above-mentioned formula (9) during n=1, i.e. situation shown in the foregoing description 2; When n=2, i.e. situation shown in the foregoing description 1; When n=3, also can adopt, just calculate relative complex some.In addition, according to mathematical model and the formula (9) of above-mentioned each difference E, also have a kind of situation of equivalence in fact, promptly the mathematical model of difference E can be expressed as the reference filter amplitude-frequency response | H ₀(f) | with when the pre-filter amplitude-frequency response | H (f) | difference overlapping bands [0, min (Fr ₀/ 2, Fr _t/ 2)] Nei 2n power sum, promptly

$E=\underset{f\&Element;[0,\min ({\mathrm{<figure-callout\; id="0"\; label="Fr"\; filenames="A2008101427870026H1.png,A2008101427870027H2.png"\; state="\{\{state\}\}">Fr</figure-callout>}}_0/2,{\mathrm{Fr}}_t/2)]}{\mathrm{\&Sigma;}}{\left(\right|H\left(f\right)|-|H_0\left(f\right)\left|\right)}^{2n},---\left(10\right)$

Wherein, n is the natural number greater than zero.In the above-mentioned formula (10) during n=1, i.e. situation shown in the foregoing description 1; When n=2, equally also be desirable account form.

Therefore, the control method of the frame correlation coefficient that the present invention proposes is not limited to organizes the gray scale imaging processing, can also be applicable to all kinds of imaging patterns such as color flow angiography, tissue doppler imaging, it can determine the optimum frame related coefficient accurately in order in the frame relevant treatment, guarantees the effect of picture smooth treatment.

Usually effectively image information changes between consecutive frame not quite, invalid noise information then changes bigger usually, utilize the relevant low-pass filter characteristic that is adopted of frame, can better keep interframe to change the little effective image information of low frequency, and suppress the interframe variation invalid noise of high frequency greatly.Adopt in the frame correlation filter amplitude-frequency response shown in Figure 1 of prior art acquisition, can find out significantly between each curve to differ greatly, have more noise information; And adopt in Fig. 4 that method of the present invention obtains and the frame correlation filter amplitude-frequency response shown in Figure 5, have consistent frame relevant effect between each adjacent curve substantially, and each curve has similar amplitude versus frequency characte in overlapped frequency band.As seen, the present invention passes through different imaging frame rates, thereby the corresponding frame correlation coefficient of optimized choice obtains the frame relevant effect of the basically identical under the different imaging frame rates, has guaranteed the smoothing processing effect and the Noise Suppression effect of Flame Image Process effectively.

Control method according to above-mentioned frame correlation coefficient, the present invention is also corresponding to provide a kind of frame correlation coefficient controller, the optimum frame related coefficient that it can directly obtain under the current imaging frame rate guarantees that the wave filter amplitude-frequency response under the different imaging frame rates has close frequency response characteristic in overlapping bands.As shown in Figure 6, described controller comprises:

First module 300 is used for according to default benchmark imaging frame rate Fr ₀Calculate benchmark imaging frame rate Fr ₀Under frame correlation coefficient a (Fr ₀);

Second unit 310 is used for the frame correlation coefficient a (Fr that obtains according to first module 300 ₀) calculating reference filter amplitude-frequency response | H ₀(f) |; And

The 3rd unit 320 is used for more current imaging frame rate Fr _tUnder when the pre-filter amplitude-frequency response | H (f) | with described reference filter amplitude-frequency response | H ₀(f) | the difference E in overlapping bands, export described difference E for hour when the pre-filter amplitude-frequency response | H (f) | pairing frame correlation coefficient a (Fr _t).

The parameter a (Fr here ₀), Fr ₀, | H ₀(f) |, Fr _t, E, | H (f) |, a (Fr _t), the calculating or the setting principle of overlapping bands, can be referring to the implementation process of the control method of above-mentioned frame correlation coefficient.

As shown in Figure 7, for calculated difference E, can in the 3rd unit 320 of controller, set up with lower unit:

Differential pattern unit 321 is used to store described when the pre-filter amplitude-frequency response | H (f) | with described reference filter amplitude-frequency response | H ₀(f) | difference mathematical model E=F (| H (f) |, | H ₀(f) |), and it is described when the pre-filter amplitude-frequency response to utilize this mathematic(al) mode to calculate | H (f) | with described reference filter amplitude-frequency response | H ₀(f) | difference E; And

Comparing unit 322 is used for more described difference E, export described difference E for hour when the pre-filter amplitude-frequency response | H (f) | pairing frame correlation coefficient.Adopt this structure, and utilize the foregoing description 4, promptly can realize calculating in real time the optimum frame related coefficient under the current imaging frame rate; If but adopt the foregoing description 1,2 or at 3 o'clock, relate in the time of from a plurality of candidate frame related coefficients, to select, described the 3rd unit 320 just need increase following unit again on the basis of differential pattern unit 321 and comparing unit 322, as shown in Figure 7, described the 3rd unit 320 also comprises:

Candidate set computing module 323 is used to generate current imaging frame rate Fr _tUnder candidate frame related coefficient a` (Fr _t);

Wave filter amplitude-frequency response computing module 324 is used for described candidate frame related coefficient a` (Fr <sub>t</sub>) be input in the transfer function model 325 of digital filter calculated candidate frame correlation coefficient a` (Fr _t) corresponding to the pre-filter amplitude-frequency response | H (f) |, with this when the pre-filter amplitude-frequency response | H (f) | be input to and carry out difference in the described differential pattern unit 321 and calculate, and relatively obtain corresponding frame correlation coefficient in the back by comparing unit 322.

Need to preserve and set up quick demand with relation table based on data result, frame correlation coefficient controller of the present invention can increase by a storage unit 330 on the basis of structure shown in Figure 6, and it is used to write down current imaging frame rate Fr _tUnder optimum frame related coefficient a (Fr _t), this optimum frame related coefficient a (Fr _t) be described difference E for hour when the pre-filter amplitude-frequency response | H (f) | pairing frame correlation coefficient, promptly from selecting frame correlation coefficient a` (Fr _t) in the frame correlation coefficient selected according to the minimum principle of difference.The storage unit 330 here can be provided with a relation table, and with the optimum frame related coefficient a (Fr that writes down _t) add wherein, utilize this relation table to write down current imaging frame rate Fr _t, current imaging frame rate Fr _tUnder optimum frame related coefficient a (Fr _t), and characterize corresponding relation between the relevant control coefrficient k three of frame of frame relevant effect.

From the structrual description of above-mentioned frame correlation coefficient controller as can be seen, it mainly is to utilize the control method of above-mentioned frame correlation coefficient and set up a kind of product, this product adopts the control method of above-mentioned frame correlation coefficient can obtain optimum frame related coefficient under the current frame rate, utilizing this frame correlation coefficient to carry out ultrasonoscopy handles, can guarantee that the wave filter amplitude-frequency response under the different imaging frame rates has close frequency response characteristic in overlapping bands, and effectively guarantee the smooth effect and the noise suppression effect of Flame Image Process.

Based on the application of control method in the frame relevant treatment of above-mentioned frame correlation coefficient, the present invention also provides a kind of ultrasonoscopy frame correlation processing method, and this method may further comprise the steps:

Step S1 adopts the control method of above-mentioned frame correlation coefficient to obtain current imaging frame rate Fr _tPairing optimum frame related coefficient a (Fr _t);

Step S2 is with the optimum frame related coefficient a (Fr that obtains _t) be input in the mathematical model of frame relevant treatment, carry out the frame related operation, the current frame image after obtaining to handle.The frame relevant treatment mathematical model here can adopt aforementioned formula (1), and its specific embodiment can be referring to Fig. 3.As seen from Figure 3, calculate optimum frame related coefficient a (Fr at the foregoing description 1,2 or 3 _t) after, as long as utilize this frame correlation coefficient to carry out the frame relevant treatment of image.

In the ultrasonoscopy frame correlation processing method proposed by the invention, about optimum frame related coefficient a (Fr _t) computation process with and the technical scheme expanded referring to above-mentioned explanation, in this no longer repeat specification about the frame correlation coefficient control method.

On the basis of above-mentioned frame correlation coefficient control method and frame correlation processing method thereof, the present invention also provides a kind of new ultrasonic image-forming system, as shown in Figure 8, described ultrasonic image-forming system comprises: ultrasonoscopy processing module and the probe that is used to obtain ultrasonoscopy; Be provided with a frame correlation coefficient controller 400 and a frame relevant treatment unit 410 in the described ultrasonoscopy processing module, the structure that the frame correlation coefficient controller 400 here adopts as shown in Figure 6 specifically can be referring to above stated specification; Described frame relevant treatment unit 410 is used for the frame correlation coefficient of Unit the 3rd 320 outputs of received frame related coefficient controller 400, and this frame correlation coefficient is input in the mathematical model of frame relevant treatment and carries out the frame related operation, obtain the current frame image after the smoothing processing.In this ultrasonic image-forming system, about the content of frame correlation coefficient controller 400 with and the technical scheme expanded referring to above-mentioned explanation, in this no longer repeat specification about frame correlation coefficient controller shown in Figure 6.

Based on the implementation that above-mentioned optimum frame related coefficient can adopt lookup table mode to carry out, the present invention also provides a kind of new ultrasonic image-forming system, as shown in Figure 9, comprises in this system: ultrasonoscopy processing module and the probe that is used to obtain ultrasonoscopy; And, in the ultrasonoscopy processing module, be provided with a storage medium 430, search a unit 420 and a frame relevant treatment unit 410 shown in Figure 6, described storage medium 430 is preserved a relation table, this table record has optimum frame related coefficient under current imaging frame rate, the current imaging frame rate, and characterizes corresponding relation between the relevant control coefrficient three of frame of frame relevant effect, the difference minimum of reference filter amplitude-frequency response in overlapping bands under a pre-filter amplitude-frequency response and a benchmark imaging frame rate of described optimum frame related coefficient correspondence; Described frame relevant treatment unit 410 links to each other with described storage medium 430 by the described unit 420 of searching, the described unit 420 of searching is used for searching described relation table and current imaging frame rate and the corresponding optimum frame related coefficient of the relevant control coefrficient of present frame, and this optimum frame related coefficient is sent in the described frame relevant treatment unit 410; Described frame relevant treatment unit 410 is used for the mathematical model that described optimum frame related coefficient is input to the frame relevant treatment is carried out the frame related operation, the current frame image after obtaining to handle.

Ultrasonic image-forming system shown in Figure 9 is: the optimum frame related coefficient that adopts above-mentioned frame correlation coefficient control method to be obtained is set up a relation table, the corresponding frame correlation coefficient of acquisition is used for tabling look-up in real time when Flame Image Process, do like this and can reduce calculated amount, improve the speed of Flame Image Process.How the key issue of building table is the calculating optimum frame correlation coefficient, and it can be referring to above-mentioned specifying about the frame correlation coefficient control method.Such as: adopt the mode of the foregoing description 1,2 or 3 as figure, the optimum frame related coefficient can adopt following method to obtain:

At first, set a plurality of candidate frame related coefficients under the current imaging frame rate, the system of selection of this candidate frame related coefficient is as follows:

According to the exponential function of frame correlation coefficient and imaging frame rate, calculate the frame correlation coefficient estimated value under the current imaging frame rate; Select N value as the candidate frame related coefficient near described estimated value, this N is the natural number more than or equal to 2;

Then, respectively described N candidate frame related coefficient is input in the transfer function model of digital filter, calculate each candidate frame related coefficient correspondence when the pre-filter amplitude-frequency response;

At last, comparing when pre-filter amplitude-frequency response and described reference filter amplitude-frequency response (its computation process can referring to the related description of the foregoing description 1) described N candidate frame related coefficient correspondence respectively, according to working as pre-filter amplitude-frequency response and the difference of described reference filter amplitude-frequency response in overlapping bands is minimum principle, from described N candidate frame related coefficient, select one as the pairing optimum frame related coefficient of current imaging frame rate, promptly described difference be hour when the pairing candidate frame related coefficient of pre-filter amplitude-frequency response.If implement 4 or 5 but adopt, then can specify referring to above-mentioned.

In sum, the present invention is by setting the frame correlation coefficient under the different frame per second, feasible corresponding wave filter amplitude-frequency response has close frequency response characteristic in overlapping frequency band requirement, a kind of computing method of frame correlation coefficient are provided, based on these computing method, the present invention has derived a kind of frame correlation control unit that can make stand-alone product and be used to obtain the optimum frame related coefficient again, a kind of ultrasonic image-forming system that utilizes the frame correlation processing method of above-mentioned frame correlation coefficient computing method and utilize this method, and a kind of employing contains the ultrasonic image-forming system of the storage medium of optimum frame related coefficient relation table.For last ultrasonic image-forming system, the optimum frame related coefficient relation table that contains in its storage medium adopts above-mentioned frame correlation coefficient computing method to obtain.The whole bag of tricks disclosed in this invention and system, all can calculate the optimum frame related coefficient that obtains under the current imaging frame rate according to the minimum difference principle, and be used for subsequent image processing, make the present invention when bigger change takes place imaging frame rate, the treatment effect that ultrasonic image frame is relevant remains unchanged substantially.

Should be understood that, for those of ordinary skills, can be improved according to the above description or conversion, and all these improvement and conversion all should belong to the protection domain of claims of the present invention.

Claims (22)

1, a kind of control method of frame correlation coefficient is characterized in that, described method comprises:

The reference filter amplitude-frequency response under a pre-filter amplitude-frequency response and a benchmark imaging frame rate under A, the more current imaging frame rate obtains described when pre-filter amplitude-frequency response and the difference of reference filter amplitude-frequency response in overlapping bands;

B, with described difference be hour when the pairing frame correlation coefficient of pre-filter amplitude-frequency response, be judged to be the pairing optimum frame related coefficient of current imaging frame rate.

2, method according to claim 1 is characterized in that, the scope of described overlapping bands is zero closed interval to the T value, and this T value is Fr ₀/ 2 and Fr _t/ 2 smallers among both, wherein Fr ₀Be benchmark imaging frame rate, Fr _tBe current imaging frame rate.

3, method according to claim 1 is characterized in that, described steps A may further comprise the steps:

A plurality of candidate frame related coefficients under A1, the current imaging frame rate of setting;

A2, according to the transport function of digital filter, calculate each candidate frame related coefficient correspondence when the pre-filter amplitude-frequency response;

A3, respectively with the comparing when pre-filter amplitude-frequency response and described reference filter amplitude-frequency response of described each candidate frame related coefficient correspondence, obtain each and work as pre-filter amplitude-frequency response and the difference of reference filter amplitude-frequency response in overlapping bands;

And, among the described step B,, obtain minimum described difference by comparing the pairing described difference of each candidate frame related coefficient.

4, according to claim 1,2 or 3 described methods, it is characterized in that, described difference is: described reference filter amplitude-frequency response and the described n power sum of absolute value in overlapping bands of working as the difference of pre-filter amplitude-frequency response, wherein, n is the natural number greater than zero.

5, according to claim 1,2 or 3 described methods, it is characterized in that described difference is: described reference filter amplitude-frequency response under a setpoint frequency and described poor when the pre-filter amplitude-frequency response.

6, method according to claim 5 is characterized in that, described setpoint frequency is the arbitrary value except that zero in the described overlapping bands.

7, method according to claim 5 is characterized in that, described difference is meant for minimum situation: described reference filter amplitude-frequency response under a setpoint frequency and the described difference of working as the pre-filter amplitude-frequency response are zero.

8, method according to claim 7 is characterized in that, described setpoint frequency is Fr ₀/ 2 and Fr _t/ 2 smallers among both.

9, method according to claim 3 is characterized in that, the system of selection of described candidate frame related coefficient may further comprise the steps:

According to the exponential function of frame correlation coefficient and imaging frame rate, calculate the frame correlation coefficient estimated value under the current imaging frame rate;

Select N value as the candidate frame related coefficient near described estimated value, this N is the natural number more than or equal to 2.

10, according to claim 1,2 or 3 described methods, it is characterized in that described method is further comprising the steps of:

C, described optimum frame related coefficient is stored in the relation table, the optimum frame related coefficient under the current imaging frame rate of this table record, the current imaging frame rate, and characterizes corresponding relation between the relevant control coefrficient three of frame of frame relevant effect;

D, according to the relevant control coefrficient of current imaging frame rate and frame, search described relation table, determine the optimum frame related coefficient under the current imaging frame rate.

11, a kind of frame correlation coefficient controller is characterized in that, described controller comprises:

First module is used for according to the frame correlation coefficient under the default benchmark imaging frame rate calculating benchmark imaging frame rate;

Unit second, the frame correlation coefficient that is used for obtaining according to first module calculates the reference filter amplitude-frequency response; And

Unit the 3rd, be used under the more current imaging frame rate when pre-filter amplitude-frequency response and the difference of described reference filter amplitude-frequency response in overlapping bands, export described difference for hour work as the pairing frame correlation coefficient of pre-filter amplitude-frequency response.

12, controller according to claim 11 is characterized in that, described Unit the 3rd comprises:

The differential pattern unit is used to calculate described difference when pre-filter amplitude-frequency response and described reference filter amplitude-frequency response; And

Comparing unit is used for more described difference, export described difference for hour when the pairing frame correlation coefficient of pre-filter amplitude-frequency response.

13, controller according to claim 12 is characterized in that, described Unit the 3rd also comprises:

The candidate set computing module is used to generate the candidate frame related coefficient under the current imaging frame rate; And

Wave filter amplitude-frequency response computing module, be used for described candidate frame related coefficient is input to the transport function of digital filter, calculated candidate frame correlation coefficient correspondence when the pre-filter amplitude-frequency response, this is input in the described differential pattern unit when the pre-filter amplitude-frequency response.

14, according to claim 11 or 12 described controllers, it is characterized in that described controller also comprises:

Be provided with the storage unit of a relation table, described relation table is used to write down optimum frame related coefficient under current imaging frame rate, the current imaging frame rate, and characterizes corresponding relation between the relevant control coefrficient three of frame of frame relevant effect; This optimum frame related coefficient be described difference for hour when the pairing frame correlation coefficient of pre-filter amplitude-frequency response.

15, a kind of ultrasonoscopy frame correlation processing method is characterized in that, said method comprising the steps of:

The reference filter amplitude-frequency response under a pre-filter amplitude-frequency response and a benchmark imaging frame rate under S1, the more current imaging frame rate obtains described when pre-filter amplitude-frequency response and the difference of reference filter amplitude-frequency response in overlapping bands;

S2 with described difference be hour when the pairing frame correlation coefficient of pre-filter amplitude-frequency response, be judged to be the pairing optimum frame related coefficient of current imaging frame rate;

The optimum frame related coefficient that S3, utilization obtain is carried out the frame related operation, the current frame image after obtaining to handle.

16, method according to claim 15 is characterized in that, may further comprise the steps between described step S2 and the step S3:

Described optimum frame related coefficient is stored in the relation table, the optimum frame related coefficient under the current imaging frame rate of this table record, the current imaging frame rate, and characterizes corresponding relation between the relevant control coefrficient three of frame of frame relevant effect;

According to current imaging frame rate and the relevant control coefrficient of frame, search described relation table, determine the optimum frame related coefficient under the current imaging frame rate.

17, a kind of ultrasonic image-forming system, described system comprises: ultrasonoscopy processing module and the probe that is used to obtain ultrasonoscopy; It is characterized in that be provided with a frame correlation coefficient controller and a frame relevant treatment unit in the described ultrasonoscopy processing module, this controller comprises:

First module is used for according to the frame correlation coefficient under the default benchmark imaging frame rate calculating benchmark imaging frame rate;

Unit second, the frame correlation coefficient that is used for obtaining according to first module calculates the reference filter amplitude-frequency response; And

Unit the 3rd, be used under the more current imaging frame rate when pre-filter amplitude-frequency response and the difference of described reference filter amplitude-frequency response in overlapping bands, export described difference for hour work as the pairing frame correlation coefficient of pre-filter amplitude-frequency response;

Described frame relevant treatment unit is used to receive the frame correlation coefficient of described Unit the 3rd output, and utilizes this frame correlation coefficient to carry out the frame related operation, the current frame image after obtaining to handle.

18, ultrasonic image-forming system according to claim 17 is characterized in that, described Unit the 3rd comprises:

The differential pattern unit is used to calculate described difference when pre-filter amplitude-frequency response and described reference filter amplitude-frequency response; And

Comparing unit is used for more described difference, export described difference for hour when the pairing candidate frame related coefficient of pre-filter amplitude-frequency response.

19, ultrasonic image-forming system according to claim 18 is characterized in that, described Unit the 3rd also comprises:

The candidate set computing module is used to generate the candidate frame related coefficient under the current imaging frame rate; And

Wave filter amplitude-frequency response computing module, be used for described candidate frame related coefficient is input to the transport function of digital filter, calculated candidate frame correlation coefficient correspondence when the pre-filter amplitude-frequency response, this is input in the described differential pattern unit when the pre-filter amplitude-frequency response.

20, according to claim 17 or 18 described ultrasonic image-forming systems, it is characterized in that described ultrasonic image-forming system also comprises:

Be provided with the storage unit of a relation table, described relation table is used to write down optimum frame related coefficient under current imaging frame rate, the current imaging frame rate, and characterizes corresponding relation between the relevant control coefrficient three of frame of frame relevant effect; This optimum frame related coefficient be described difference for hour when the pairing frame correlation coefficient of pre-filter amplitude-frequency response.

21, a kind of ultrasonic image-forming system, described system comprises: ultrasonoscopy processing module and the probe that is used to obtain ultrasonoscopy; It is characterized in that, be provided with a storage medium in the described ultrasonoscopy processing module, search a unit and a frame relevant treatment unit,

Described storage medium is preserved a relation table, this table record has optimum frame related coefficient under current imaging frame rate, the current imaging frame rate, and characterizes corresponding relation between the relevant control coefrficient three of frame of frame relevant effect, the difference minimum of reference filter amplitude-frequency response in overlapping bands under a pre-filter amplitude-frequency response and a benchmark imaging frame rate of described optimum frame related coefficient correspondence;

Described frame relevant treatment unit links to each other with described storage medium by the described unit of searching, the described unit of searching is used for searching described relation table and current imaging frame rate and the corresponding optimum frame related coefficient of the relevant control coefrficient of present frame, and this optimum frame related coefficient is sent in the described frame relevant treatment unit;

Described frame relevant treatment unit is used to utilize described optimum frame related coefficient to carry out the frame related operation, the current frame image after obtaining to handle.

22, ultrasonic image-forming system according to claim 21 is characterized in that, the computation process of described optimum frame related coefficient may further comprise the steps:

A plurality of candidate frame related coefficients under C1, the current imaging frame rate of setting, the system of selection of this candidate frame related coefficient is as follows:

According to the exponential function of frame correlation coefficient and imaging frame rate, calculate the frame correlation coefficient estimated value under the current imaging frame rate; Select N value as the candidate frame related coefficient near described estimated value, this N is the natural number more than or equal to 2;

C2, according to the transport function of digital filter, calculate each candidate frame related coefficient correspondence when the pre-filter amplitude-frequency response;

C3, comparing when pre-filter amplitude-frequency response and described reference filter amplitude-frequency response described N candidate frame related coefficient correspondence respectively, with described difference be hour when the pairing candidate frame related coefficient of pre-filter amplitude-frequency response, be judged to be described optimum frame related coefficient.

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