JP2015084861A - Signal processing device and method, and computer program and recording medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a signal processing device capable of displaying an input signal in a further easily viewable mode.SOLUTION: A signal processing device 10 includes: recognition means 113 that recognizes a period of an input signal with periodicity; generation means 104 that generates display data for displaying characteristics of the input signal for n-number (where, n represents an integer of 1 or more) of continuous periods on the basis of periods recognized by the recognition means, in a display mode where a display size of the characteristics of the input signal for the n-number of continuous periods and the display size along a direction corresponding to a temporal axis turns out a fixed size regardless of the length of the n-number of continuous periods; and output means that outputs display data to a display device.

Description

  The present invention relates to a signal processing apparatus and method for processing an input signal such as a respiratory sound signal, and a technical field of a computer program and a recording medium.

  A body sound such as a breathing sound is used as one of indices when a doctor diagnoses a pathological condition of the body. For this reason, in order to favorably assist diagnosis of medical conditions by medical personnel such as doctors, a display device that displays characteristics (for example, signal intensity) of body sounds (in other words, visualizes body sounds) has been proposed. Yes. When the display device displays the characteristics of the body sound, the medical staff can recognize the body sound suitably or relatively easily.

  Note that Patent Documents 1 to 2 are cited as prior art documents related to the present invention. Patent Document 1 discloses a method of processing an unsteady signal including a segment having an amplitude that increases or decreases representing a physiological characteristic of a subject having a sense, although it is not a display device that displays a biological sound signal indicating a biological sound. A method is disclosed for detecting a segment that includes a portion where the amplitude of the signal changes from increasing to decreasing or vice versa by determining an instant when the time derivative of the signal is approximately equal to zero. Patent Document 2 is an apparatus for assisting and promoting patient respiration performed in a repetitive breathing cycle having an inhalation phase and an expiration phase, although it is not a display device that displays a body sound signal indicating a body sound. In determining the point of inhalation in the patient's breathing cycle and the point at which subsequent exhalation begins, the time reference is normalized taking into account that the inhalation time varies with each breath. An apparatus for normalizing a time reference for respiratory admittance using a template is disclosed.

JP 2005-506115 A JP-A-6-503484

  In order for a medical staff to diagnose a pathological condition, information on how the characteristics of the body sound change (so-called changes in the characteristics of the body sound over time) can be useful information. Therefore, it is preferable that the display device that displays the characteristics of the body sound displays the characteristics of the body sound in a manner that allows the change in the characteristics over time to be identified.

  By the way, biological sounds often have periodicity (that is, characteristics change periodically). That is, the biological sound often has a periodicity that its characteristics change while repeating increase and decrease periodically.

  Here, a display device that displays the characteristics of the body sound for each period as a signal waveform as it is (that is, displays the characteristics of the body sound for one period as a signal waveform for each period) is taken as an example. In this case, when the period of the body sound changes (that is, becomes longer or shorter), the display size (that is, the length) along the time axis of the signal waveform indicating the characteristics of the body sound for each period changes. become. Specifically, the display size along the time axis of the signal waveform indicating the characteristic of the biological sound having a period of 4 seconds is the display size along the time axis of the signal waveform indicating the characteristic of the biological sound having a period of 5 seconds. Smaller than size. When the display size along the time axis of the signal waveform indicating the characteristics of the biological sound for each period changes, the display position where the characteristic waveform of the biological sound for one period appears changes. There is a risk that. That is, it is assumed that if a characteristic waveform of biological sound for one cycle is originally displayed at the same display position, the characteristic waveform is easily recognized (for example, easy to compare) at a certain timing. If the characteristic waveform is displayed at the first display position and the characteristic waveform is displayed at the second display position at another subsequent timing, the characteristic waveform that should originally show the same characteristic is displayed. A technical problem arises that the waveform may be misrecognized as a different waveform.

  Furthermore, each period of the body sound may be further subdivided according to the characteristics of the body sound. For example, when focusing on a breathing sound that is an example of a biological sound, each cycle of the breathing sound may be subdivided into a period in which expiration is performed and a period in which inspiration is performed. Such subdivided periods can also vary with cycle variations. Accordingly, a similar technical problem occurs in a display device that displays the characteristics of biological sounds for each period obtained by subdividing the cycle as a signal waveform.

  It should be noted that not only the body sound but also the characteristics of any periodic input signal (that is, an arbitrary input signal whose characteristics such as signal intensity change periodically) are displayed on the display device. Problems arise.

  The present invention has been made in view of, for example, the conventional problems described above, and provides a signal processing apparatus and method, a computer program, and a recording medium capable of displaying the characteristics of an input signal in a more easily viewable manner, for example. This is the issue.

  In order to solve the above-described problem, the first signal processing apparatus includes a recognition unit that recognizes a cycle of an input signal having periodicity, and n (where n is 1) based on the cycle recognized by the recognition unit. (Integer above) The characteristic of the input signal for the number of consecutive periods is the display size of the characteristic of the input signal for the number n of consecutive periods, and the display size along the direction corresponding to the time axis Includes generation means for generating display data for display in a display mode having a fixed size regardless of the length of n consecutive cycles, and output means for outputting the display data to a display device.

  In order to solve the above-mentioned problem, the second signal processing device recognizes a segmentation period obtained by subdividing each cycle of an input signal having periodicity, and the recognition unit recognizes the segmentation period. Based on the subdivision period, the characteristics of the input signal for m consecutive subdivision periods (where m is an integer of 1 or more) are the characteristics of the input signal for the m consecutive subdivision periods. Generating display data for display in a display mode in which the display size along the direction corresponding to the time axis is a fixed size regardless of the length of m consecutive subdivision periods Means and output means for outputting the display data to a display device.

  In order to solve the above problems, a first signal processing method includes a recognition step of recognizing a cycle of an input signal having periodicity, and n (where n is 1) based on the cycle recognized by the recognition step. (Integer above) The characteristic of the input signal for the number of consecutive periods is the display size of the characteristic of the input signal for the number n of consecutive periods, and the display size along the direction corresponding to the time axis Includes a generation step of generating display data for display in a display mode having a fixed size regardless of the length of n consecutive cycles, and an output step of outputting the display data to a display device.

  In order to solve the above-described problem, a second signal processing method includes a recognition step of recognizing a subdivision period obtained by subdividing each cycle of an input signal having periodicity, and the recognition step recognized Based on the subdivision period, the characteristics of the input signal for m consecutive subdivision periods (where m is an integer of 1 or more) are the characteristics of the input signal for the m consecutive subdivision periods. Generating display data for display in a display mode in which the display size along the direction corresponding to the time axis is a fixed size regardless of the length of m consecutive subdivision periods A process, and an output process for outputting the display data to a display device.

  In order to solve the above-mentioned problem, a first computer program is a computer program executed by a computer, and a recognition step for recognizing a cycle of an input signal having periodicity, and a cycle recognized by the recognition step. Based on the characteristic of the input signal for n consecutive periods (where n is an integer equal to or greater than 1), the display size of the characteristic of the input signal for the n consecutive periods and the time A generation step of generating display data for display in a display mode in which the display size along the direction corresponding to the axis is a fixed size regardless of the length of n consecutive cycles, and the display data And causing the computer to execute an output step of outputting to the computer.

  In order to solve the above-mentioned problem, the second computer program is a computer program executed by a computer, and recognizes a subdivision period obtained by subdividing each period of an input signal having periodicity And m (where m is an integer equal to or greater than 1) consecutive subdivided periods, the characteristics of the input signal corresponding to the m subdivided periods recognized by the recognition step and the recognition step. In a display mode in which the display size of the characteristics of the input signal for the subdivision period and the display size along the direction corresponding to the time axis is a fixed size regardless of the length of m consecutive subdivision periods The computer is caused to execute a generation step of generating display data for display and an output step of outputting the display data to a display device.

  In order to solve the above problems, a first recording medium is a recording medium on which a computer program executed by a computer is recorded, and a recognition step for recognizing a period of an input signal having periodicity, and the recognition Based on the period recognized by the process, the characteristics of the input signal for n consecutive periods (where n is an integer equal to or greater than 1) are expressed as the characteristics of the input signal for the n consecutive periods. A generation step of generating display data for display in a display mode which is a display size and the display size along the direction corresponding to the time axis is a fixed size regardless of the length of n consecutive cycles; The computer program which makes the said computer perform the output process which outputs the said display data to a display apparatus is recorded.

  In order to solve the above problems, a second recording medium is a recording medium on which a computer program executed by a computer is recorded, and is obtained by subdividing each period of an input signal having periodicity. Based on the recognition step for recognizing the subdivision period, and the subdivision period recognized by the recognition step, the characteristics of the input signal for m (where m is an integer of 1 or more) consecutive subdivision periods are obtained. The display size of the characteristic of the input signal for the m consecutive subdivision periods and the display size along the direction corresponding to the time axis is irrespective of the length of the m consecutive subdivision periods. A computer program for causing a computer to execute a generation step of generating display data for display in a display mode having a fixed size, and an output step of outputting the display data to a display device It has been recorded.

It is a block diagram which shows the structure of the signal processing apparatus of a present Example. It is a flowchart which shows the flow of operation | movement of the signal processing apparatus of a present Example. It is the graph which shows an example of the mounting | wearing aspect with respect to the biological body of a signal acquisition part, and the graph which shows the waveform of a respiratory sound signal on a time axis. It is a schematic diagram which shows an example of the operation | movement which a signal memory | storage part memorize | stores a respiratory sound signal. It is a classification chart which shows the kind of breathing sound. Five types of breathing sounds (alveolar breathing sounds, low-pitched continuous rales (sounding sounds), high-pitched continuous rales (flute sounds), fine intermittent rales (twisting sounds), and coarse intermittent rales It is a graph which shows the waveform of five types of signal components equivalent to (water bubble sound)) on a time axis. It is a graph which shows the 1st aspect of a period determination process with the waveform of a respiratory sound signal. It is a graph which shows the 2nd aspect of a period determination process with the waveform of a respiratory sound signal. It is a top view which shows an example of the display mode of the signal component (respiration sound signal) implement | achieved by the display data which a display data production | generation part produces | generates. It is a schematic diagram which shows an example of the conversion process for making the display size (specifically display size along a time axis) of the alveolar respiratory sound component for 1 period into a fixed size. An example of a display mode in which the display size of the amplitude level of the signal component for one cycle does not become a fixed size (that is, the display size of the amplitude level of the signal component for one cycle varies according to the length of one cycle). FIG. It is a top view which shows an example of the display mode which displays the amplitude level of the signal component which comprises a respiratory sound signal using the display target object different from the pie chart shown in FIG. It is a top view which shows an example of the display mode which displays the amplitude level of the signal component which comprises a respiratory sound signal using the display target object different from the pie chart shown in FIG. It is a top view which shows an example of the display mode which displays the amplitude level of the signal component which comprises a respiratory sound signal using the display target object different from the pie chart shown in FIG.

  Hereinafter, embodiments of a signal processing apparatus and method, a computer program, and a recording medium will be described in order.

(Embodiment of signal processing apparatus)
<1>
The signal processing apparatus according to the first embodiment includes recognition means for recognizing the period of an input signal having periodicity, and n (where n is an integer of 1 or more) based on the period recognized by the recognition means. The characteristic of the input signal for the continuous period is the display size of the characteristic of the input signal for the n consecutive periods, and the display size along the direction corresponding to the time axis is n continuous. A generating unit configured to generate display data for display in a display mode having a fixed size regardless of the length of the cycle; and an output unit configured to output the display data to a display device.

  The signal processing apparatus according to the first embodiment performs signal processing for displaying characteristics of an input signal (that is, an arbitrary index that can specify the state of the input signal, for example, signal strength) on a display device. I do. That is, the signal processing device according to the first embodiment performs signal processing for displaying on the display device some display object capable of visually specifying the characteristics of the input signal.

  The input signal to be subjected to signal processing performed by the signal processing apparatus according to the first embodiment has periodicity. Here, “periodicity” means a property that characteristics (typically, signal strength) change periodically. More specifically, “periodicity” means a property in which characteristics change while repeating increase and decrease periodically. In other words, “periodicity” means a property in which characteristics change repeatedly in the same or similar manner or in the same or similar tendency.

  In particular, the signal processing apparatus according to the first embodiment includes at least a recognition unit, a generation unit, and an output unit in order to perform signal processing for displaying the characteristics of an input signal on a display device.

  The recognition means recognizes the period of the input signal. The “cycle” here means a period required for one change among repeated changes in the characteristics of the input signal. Therefore, when the change in the same mode of the input signal is repeated a plurality of times, the period required for one change in the same mode is a cycle.

  In the first embodiment, the period of the input signal may be always constant. In this case, the recognizing unit continuously recognizes a constant cycle (that is, a period) continuously as the cycle of the input signal. For example, the recognition unit continuously recognizes that the period at the second timing following the first timing is the first period after recognizing that the period at the first timing is the first period. It will be.

  Alternatively, the period of the input signal may vary with time. In this case, the recognizing unit continuously recognizes a cycle (that is, a period) that varies with the passage of time as the cycle of the input signal. For example, the recognizing unit recognizes that the period at the first timing is the first period, and then the second period after the first timing is different from the first period. It will be recognized that.

  The generation means generates display data for displaying the characteristics of the input signal on the display device based on the period of the input signal recognized by the recognition means. In the first embodiment, the generation unit generates display data for displaying the characteristics of the input signal for n consecutive periods (that is, for n consecutive periods recognized continuously by the recognition unit). To do. In other words, the generation means generates display data for displaying the characteristics of the input signal every n consecutive periods. In other words, the generation unit generates display data for displaying the characteristics of the input signal in a display unit of n consecutive periods.

  Furthermore, in the first embodiment, the generation unit displays the display size of the characteristics of the input signal for n consecutive periods (specifically, the display size along the direction corresponding to the time axis, and so on). Display data is generated so that a display mode with a fixed size is realized. In other words, the generating means displays the characteristic of the input signal for n consecutive periods in such a manner that the display size of the characteristic of the input signal for n consecutive periods is a fixed size. Generate data.

  The “fixed size” mentioned here is a size that does not vary regardless of the length of n consecutive cycles (that is, the time length of n consecutive cycles) (that is, the length of n consecutive cycles). The size is constant regardless of the presence or absence of fluctuations). Therefore, the generation means always has the same display size of the characteristic of the input signal for n consecutive periods even when the length of n consecutive periods varies with the passage of time. Thus, display data is generated. For example, even when the length of n consecutive cycles varies from A second to B seconds with the passage of time, the generation unit corresponds to the first time length (for example, A seconds). The display size of the characteristic of the input signal for n consecutive periods is the same as the display size of the characteristic of the input signal for n consecutive periods corresponding to the second time length (for example, B seconds). Display data is generated so that

  More specifically, for example, the generation means uses n pie charts in which the circumferential direction is associated with the time axis and the radiation direction is associated with the characteristics of the input signal. A case where display data for displaying the characteristics of the input signal is generated will be described as an example. In this case, the display size (that is, the display size along the circumference) of the characteristic of the input signal for n consecutive periods is, for example, a fixed size (that is, regardless of the length of n consecutive periods). Fixed length). For example, the display size of the characteristic of the input signal for n consecutive periods corresponding to a first time length (for example, A seconds) and n consecutive times corresponding to a second time length (for example, B seconds) Both the display sizes of the characteristics of the input signal for the period to be a fixed size (for example, fixed length X) corresponding to the entire circumference of the pie chart.

  Alternatively, for example, the generation unit may calculate the characteristics of the input signal for n consecutive periods using a bar graph in which the horizontal axis is associated with the time axis and the vertical axis is associated with the characteristics of the input signal. A case where display data for display is generated will be described as an example. In this case, the display size (that is, the display size along the horizontal axis) of the characteristics of the input signal for n consecutive cycles is, for example, a fixed size (that is, the display size along the horizontal axis). Fixed length). For example, the display size of the characteristic of the input signal for n consecutive periods corresponding to a first time length (for example, A seconds) and n consecutive times corresponding to a second time length (for example, B seconds) Both the display sizes of the characteristics of the input signal for the period to be a fixed size (for example, a fixed length Y) corresponding to the length of at least a part of the horizontal axis.

  The output means outputs the display data generated by the generation means to the display device. As a result, the display device displays the characteristics of the input signal based on the display data generated by the generation unit. In other words, the display device fixes the characteristics of the input signal for n consecutive periods regardless of the length of the period of n consecutive periods where the display size of the characteristics of the input signal for the n consecutive periods is fixed. It can be displayed in a display mode that is a size.

  Here, in describing the technical effect of the signal processing apparatus of the first embodiment, it will be described in comparison with the signal processing apparatus of the first comparative example. Note that the signal processing device of the first comparative example shows the characteristics of the input signal for n consecutive periods, and the display size of the characteristics of the input signal for n consecutive periods is the length of n consecutive periods. It is assumed that display data to be displayed in a display mode that varies depending on the size is generated. The display device that operates based on the display data generated by the signal processing device of the first comparative example has the characteristics of the input signal for n consecutive periods and the characteristics of the input signal for n consecutive periods. The display size of the characteristic is displayed in a display mode that varies according to the length of n consecutive cycles. That is, the display device that operates based on the display data generated by the signal processing device of the first comparative example displays the characteristics of the input signal for n consecutive periods as a signal waveform as it is. As a result, in the first comparative example, when the period of the input signal varies, the display size of the characteristic of the input signal for n consecutive periods varies along the direction corresponding to the time axis. Specifically, the display size of the characteristic of the input signal for n consecutive periods corresponding to the first time length (for example, 4 seconds) is set to a second time length longer than the first time length ( For example, the display size of the characteristic of the input signal for n consecutive periods corresponding to 5 seconds) is smaller. If the display size changes in this way, the display position at which a characteristic waveform (that is, a signal component) of the input signals for n consecutive periods appears may change. That is, it is assumed that if a characteristic waveform of input signals for n consecutive periods is originally displayed at the same display position, the characteristic waveform is easily recognized (for example, easy to compare). However, a characteristic waveform is displayed at the first display position at a certain timing, and a characteristic waveform is displayed at the second display position at another subsequent timing.

  However, according to the first embodiment, even if the cycle of the input signal varies, the display size of the characteristic of the input signal for n consecutive cycles does not vary. That is, even if the cycle of the input signal varies, the display size of the characteristics of the input signal for n consecutive cycles does not vary along the direction corresponding to the time axis. Specifically, the display size of the characteristic of the input signal for n consecutive periods corresponding to the first time length (for example, 4 seconds) is set to a second time length different from the first time length ( For example, the display size of the characteristic of the input signal for n consecutive periods corresponding to 5 seconds) is the same. Since the display size is fixed in this way, the display position at which a characteristic waveform (that is, signal component) among the input signals for n consecutive periods appears is due to the fluctuation of the period of the input signal. Thus, there is little or no fluctuation. That is, in the first embodiment, the characteristic waveform of the input signals for n consecutive cycles is displayed (or easily displayed) at the same or substantially the same display position. An observer who observes the apparatus can appropriately recognize the characteristics of the input signal.

  Thus, according to the signal processing device of the first embodiment, the characteristics of the input signal are suitably displayed.

<2>
In another aspect of the signal processing apparatus according to the first embodiment, the generation unit performs the conversion process of compressing or expanding the input signal for the n consecutive periods along a time axis, thereby performing the display. Generate data.

  According to this aspect, the generation unit performs the conversion process of compressing or expanding the input signal for n consecutive periods along the time axis, thereby obtaining the characteristic of the input signal for n consecutive periods. Display data can be generated so that a display mode in which the display size is a fixed size is realized.

<3>
As described above, in another aspect of the signal processing apparatus that generates display data by performing a conversion process of compressing or expanding an input signal for n consecutive periods along the time axis, the n consecutive periods are used. The characteristics of the input signal in minutes are indicated by M (where M is an integer greater than or equal to 1) sample values, and the characteristics of the input signal for the n consecutive periods are respectively When one sample value can be displayed and displayed using N (N is an integer greater than or equal to 1 and less than or equal to M) areas arranged in the direction corresponding to the time axis The generating means generates the display data by performing the conversion process so that an average value of M / N sample values is displayed in each region portion.

  According to this aspect, the generation unit performs the conversion process (substantially the same process as the process of compressing the input signal along the time axis) to calculate the average value of the sample values of the input signal, Display data can be generated.

<4>
In another aspect of the signal processing device according to the first embodiment, the generation unit has a fixed position on the display screen from a display start position where the position of the display device on the display screen is fixed. On the display screen in which a direction toward a predetermined display end position is associated with a time axis, display of the input signal characteristics for the n consecutive periods from the display start position is started. The display data is generated so that the display of the characteristics of the input signal for the n consecutive periods at the end position can be ended.

  According to this aspect, even if the period of the input signal varies, (i) the display size of the characteristic of the input signal for n consecutive periods does not vary, and (ii) n consecutive The display start position and display end position of the characteristics of the input signal for the period to be changed do not change. For this reason, the display position at which a characteristic waveform (that is, a signal component) of the input signals for n consecutive periods appears is largely fluctuated due to fluctuations in the period of the input signal. Or not at all. Therefore, the various effects described above are favorably enjoyed.

<5>
In another aspect of the signal processing apparatus according to the first embodiment, the generation means includes (i) a circumferential direction associated with a time axis, and (ii) a display aspect according to the characteristics of the input signal. The display data for displaying the characteristics of the input signal for the n consecutive periods is generated using a circular graph in which the changing display object extends in the radial direction.

  According to this aspect, the generating means uses the circular graph in which the circumferential direction is associated with the time axis and the radial direction is associated with the characteristics of the input signal, for n consecutive periods. Display data for displaying the characteristics of the input signal can be generated.

<6>
In another aspect of the signal processing apparatus of the first embodiment, the input signal is a biological sound signal corresponding to a sound caused by a biological activity, and the period is a part of a biological activity that is repeatedly performed a plurality of times. This is the period required for one activity.

  According to this aspect, the signal processing apparatus can perform the signal processing described above on the biological sound signal.

  As an example of the biological sound signal, for example, a respiratory sound signal corresponding to a respiratory sound caused by the activity of respiration of a living body can be given. Such a period of the breathing sound signal may be a period required for one breath out of repeated breathing. Alternatively, as the body sound signal, for example, a heart sound signal corresponding to a heart sound caused by the activity of a heart beat of a living body can be given as an example. Such a period of the heart sound signal may be a period required for one beat of the repeated heart beats. Alternatively, as a biological sound signal, for example, a pulsating sound signal corresponding to a pulsating sound caused by the activity of a heart beat of a living body, or a blood flow sound corresponding to a blood flow sound caused by an activity of a heart beat of a living body An example is a signal. The period of the pulsation sound signal and the blood flow sound signal may be the same as the period of the heart sound signal.

<7>
In another aspect of the signal processing apparatus of the first embodiment, the input signal is a respiratory sound signal corresponding to a respiratory sound of a living body, and the period is a period required for one continuous exhalation and inspiration.

  According to this aspect, the signal processing device can perform the above-described signal processing on the respiratory sound signal.

<8>
In another aspect of the signal processing apparatus of the first embodiment, the period of the input signal varies with the passage of time.

  According to this aspect, even if the period of the input signal fluctuates, the generation unit realizes a display aspect in which the display size of the characteristic of the input signal for n consecutive periods is a fixed size. In addition, display data can be generated. For this reason, the display position at which a characteristic waveform (that is, a signal component) among the input signals for n consecutive periods appears is hardly changed due to the fluctuation of the period of the input signal. Not at all. Therefore, the various effects described above are favorably enjoyed.

<9>
The signal processing apparatus according to the second embodiment is based on a recognition unit for recognizing a subdivision period obtained by subdividing each cycle of an input signal having periodicity, and the subdivision period recognized by the recognition unit. , M (where m is an integer equal to or greater than 1), the characteristic of the input signal for the consecutive subdivided periods, and the display size of the characteristic of the input signal for the m consecutive subdivided periods, And generating means for generating display data for display in a display mode in which the display size along the direction corresponding to the time axis is a fixed size regardless of the length of m consecutive subdivision periods; and the display data Output means for outputting to the display device.

  Similar to the signal processing device of the first embodiment, the signal processing device of the second embodiment performs signal processing for displaying the characteristics of the input signal on the display device.

  Compared with the signal processing device of the first embodiment, the signal processing device of the second embodiment is obtained by subdividing the cycle of the input signal by the recognition means instead of recognizing the cycle of the input signal. It is different in that it recognizes the subdivision period that is generated. Furthermore, in the signal processing device according to the second embodiment, the generation unit generates display data for displaying the characteristics of the input signal for n consecutive periods as compared with the signal processing device according to the first embodiment. Instead, it is different in that display data for generating the characteristics of input signals for m consecutive subdivision periods is generated. Other components of the signal processing device of the second embodiment may be the same as other components of the signal processing device of the first embodiment.

  Here, the “subdivision period” means a period obtained by subdividing the period according to the characteristics of the input signal. For example, the subdivision period may mean a period obtained by subdividing the cycle according to the change tendency of the input signal (typically, the change tendency of the signal strength of the input signal over time). Good. Therefore, in the second embodiment, each cycle includes one or more subdivided periods.

  For this reason, in the second embodiment, the generation unit displays the display size of the characteristics of the input signal for m consecutive subdivision periods (specifically, the display size along the direction corresponding to the time axis, Display data is generated so that a display mode in which the same applies hereinafter is a fixed size is realized. In other words, the generation means displays the input signal characteristics for m consecutive subdivision periods in a display mode in which the display size of the input signal characteristics for m consecutive subdivision periods is a fixed size. Thus, display data is generated.

  The “fixed size” here means a size that does not vary regardless of the length of m consecutive subdivision periods (that is, the time length of m consecutive subdivision periods) (that is, m consecutive subdivision periods). This means a size that is constant regardless of whether or not the length of the subdivision period varies. Therefore, the generation means has a display size of the characteristic of the input signal for m consecutive subdivision periods even when the length of m consecutive subdivision periods varies with time. Display data is generated so as to be always the same. For example, even when the length of m consecutive subdivision periods varies from 4 seconds to 5 seconds with the passage of time, the generation means sets the first time length (for example, 4 seconds). The display size of the characteristic of the input signal corresponding to m consecutive subdivided periods and the characteristic of the input signal corresponding to m continuous subdivided periods corresponding to the second time length (for example, 5 seconds) Display data is generated so that the display size is the same.

  Here, in describing the technical effect of the signal processing apparatus of the second embodiment, it will be described in comparison with the signal processing apparatus of the second comparative example. Note that the signal processing apparatus of the second comparative example displays the characteristics of the input signal for m consecutive subdivision periods and the display size of the characteristics of the input signal for m consecutive subdivision periods. Display data for display in a display mode that varies according to the length of the subdivision period to be generated is generated. The display device that operates based on the display data generated by the signal processing device of the second comparative example has the characteristics of the input signal for m consecutive subdivision periods for m continuous subdivision periods. The display size of the characteristic of the input signal is displayed in a display mode that varies according to the length of m consecutive subdivision periods. That is, the display device that operates based on the display data generated by the signal processing device of the second comparative example displays the characteristics of the input signal for m consecutive subdivision periods as it is as a signal waveform. As a result, in the second comparative example, when the period of the input signal varies, the display size of the characteristics of the input signal for m consecutive subdivision periods varies along the direction corresponding to the time axis. . Specifically, the display size of the characteristic of the input signal for m consecutive subdivision periods corresponding to a first time length (for example, 4 seconds) is a second time longer than the first time length. It becomes smaller than the display size of the characteristic of the input signal for m consecutive subdivision periods corresponding to the long (for example, 5 seconds). If the display size changes in this way, the display position at which a characteristic waveform (that is, a signal component) of the input signals for m consecutive subdivision periods appears may change. That is, it is assumed that if a characteristic waveform among the input signals for m consecutive subdivision periods is originally displayed at the same display position, the characteristic waveform is easy to see (for example, easy to compare). However, a characteristic waveform is displayed at the first display position at a certain timing, and a characteristic waveform is displayed at the second display position at another subsequent timing.

  However, according to the second embodiment, even if the cycle of the input signal varies, the display size of the characteristics of the input signal for m consecutive subdivision periods does not vary. That is, even if the cycle of the input signal varies, the display size of the characteristics of the input signal for m consecutive subdivision periods does not vary along the direction corresponding to the time axis. Specifically, the display size of the characteristic of the input signal for m consecutive subdivision periods corresponding to a first time length (for example, 4 seconds) is a second time different from the first time length. This is the same as the display size of the characteristics of the input signal for m consecutive subdivision periods corresponding to a long length (for example, 5 seconds). Since the display size is fixed in this way, the display position at which a characteristic waveform (that is, signal component) of the input signals for m consecutive subdivision periods appears is the fluctuation of the cycle of the input signal. There is little or no significant variation due to. That is, in the second embodiment, the characteristic waveform of the input signals for m consecutive subdivision periods is displayed (or easily displayed) at the same or substantially the same display position. The observer who observes the display device can preferably recognize the characteristics of the input signal.

  Thus, according to the signal processing device of the second embodiment, the characteristics of the input signal are suitably displayed.

<10>
In another aspect of the signal processing apparatus according to the second embodiment, the generation unit performs a conversion process of compressing or expanding the input signal for the m consecutive subdivision periods along a time axis. The display data is generated.

  According to this aspect, the generation unit performs the conversion process of compressing or expanding the input signal for m consecutive subdivision periods along the time axis, thereby inputting the input for m continuous subdivision periods. Display data can be generated so as to realize a display mode in which the display size of the signal characteristics is a fixed size.

<11>
As described above, in another aspect of the signal processing apparatus that generates display data by performing conversion processing that compresses or expands input signals for m consecutive subdivision periods along a time axis, the m continuous signals are generated. The characteristic of the input signal for the subdivided period is indicated by M (where M is an integer of 1 or more) sample values, and the input signal for the m consecutive subdivided periods N regions (where N is an integer greater than or equal to 1 and less than or equal to M) arranged in the direction corresponding to the time axis, each of which is capable of displaying one sample value. In the case of using and displaying, the generation means generates the display data by performing the conversion process so that an average value of M / N sample values is displayed in each region portion.

  According to this aspect, the generation unit performs the conversion process (substantially the same process as the process of compressing the input signal along the time axis) to calculate the average value of the sample values of the input signal, Display data can be generated.

<12>
In another aspect of the signal processing device according to the second embodiment, the generation unit has a fixed position on the display screen from a display start position where the position of the display device on the display screen is fixed. On the display screen in which the direction toward the predetermined display end position is associated with the time axis, after starting the display of the characteristics of the input signal for the m consecutive subdivision periods from the display start position The display data is generated so that the display of the characteristics of the input signal for the m consecutive subdivision periods can be ended at the display end position.

  According to this aspect, even if the cycle of the input signal changes, the display size of the characteristics of the input signal for m consecutive subdivision periods does not change, and (ii) m The display start position and display end position of the characteristics of the input signal for the consecutive subdivision periods are not changed. For this reason, the display position where a characteristic waveform (that is, a signal component) of the input signals for m consecutive subdivided periods appears greatly fluctuates due to the fluctuation of the cycle of the input signal. There is little or no. Therefore, the various effects described above are favorably enjoyed.

<13>
In another aspect of the signal processing apparatus according to the second embodiment, the generation means includes (i) a circumferential direction associated with a time axis, and (ii) a display aspect according to the characteristics of the input signal. The display data for displaying the characteristics of the input signal for the m consecutive subdivision periods is generated using a circular graph in which the changing display object extends in the radial direction.

  According to this aspect, the generation means uses m circular subdivision periods using a circular graph in which the circumferential direction is associated with the time axis and the radiation direction is associated with the characteristics of the input signal. Display data for displaying the characteristics of the input signal of the minute can be generated.

<14>
In another aspect of the signal processing apparatus of the second embodiment, the input signal is a biological sound signal corresponding to a sound caused by a biological activity, and the period is a part of a biological activity that is repeatedly performed a plurality of times. It is a period required for one activity, and the plurality of segmentation periods are a plurality of segmentation periods obtained by segmenting the one activity according to the mode of the one activity.

  According to this aspect, the signal processing apparatus can perform the signal processing described above on the biological sound signal.

  As described above, respiratory sound signals, heart sound signals, pulsation sound signals, and blood flow sound signals are given as examples of biological sound signals. The subdivision period of the respiratory sound signal is a period obtained by subdividing a period required for one breath out of repeated breathing according to the mode of the one breath (for example, a period during which expiration is performed) And a period during which inhalation is performed). Alternatively, the period of the heart sound signal, the pulsation sound signal, and the blood flow sound signal is obtained by subdividing the period required for one beat among the repeated heart beats according to the mode of the one beat. (For example, a period during which the ventricle contracts and a period during which the ventricle contracts).

<15>
In another aspect of the signal processing device of the second embodiment, the input signal is a biological sound signal corresponding to a respiratory sound of a biological body, and the cycle is a period required for one continuous exhalation and inspiration. The plurality of subdivided periods include a period during which expiration is performed and a period during which inspiration is performed.

  According to this aspect, the signal processing device can perform the above-described signal processing on the respiratory sound signal.

<16>
In another aspect of the signal processing apparatus of the second embodiment, the period of the input signal varies with the passage of time.

  According to this aspect, even when the period of the input signal fluctuates, the generation unit realizes a display aspect in which the display size of the characteristics of the input signal for m consecutive subdivision periods is a fixed size. As shown, display data can be generated. For this reason, the display position at which a characteristic waveform (that is, a signal component) among the input signals for m consecutive subdivision periods appears varies due to fluctuations in the cycle of the input signal. Little or no. Therefore, the various effects described above are favorably enjoyed.

(Embodiment of signal processing method)
<17>
The signal processing method according to the first embodiment includes a recognition step for recognizing a cycle of an input signal having periodicity, and n (where n is an integer of 1 or more) based on the cycle recognized by the recognition step. The characteristic of the input signal for the continuous period is the display size of the characteristic of the input signal for the n consecutive periods, and the display size along the direction corresponding to the time axis is n continuous. A generation step of generating display data for display in a display mode having a fixed size regardless of the length of the cycle; and an output step of outputting the display data to a display device.

  According to the signal processing method of the first embodiment, it is possible to suitably enjoy the same effects as the various effects enjoyed by the signal processing device of the first embodiment described above.

  Incidentally, in response to various aspects that can be adopted by the signal processing apparatus of the first embodiment described above, the signal processing method of the first embodiment may also adopt various aspects.

<18>
The signal processing method according to the second embodiment is based on a recognition step of recognizing a subdivision period obtained by subdividing each cycle of an input signal having periodicity, and the subdivision period recognized by the recognition step. , M (where m is an integer equal to or greater than 1), the characteristic of the input signal for the consecutive subdivided periods, and the display size of the characteristic of the input signal for the m consecutive subdivided periods, And generating the display data for display in a display mode in which the display size along the direction corresponding to the time axis is a fixed size regardless of the length of m consecutive subdivision periods, and the display data Is output to the display device.

  According to the signal processing method of the second embodiment, it is possible to suitably enjoy the same effects as the various effects enjoyed by the signal processing device of the second embodiment described above.

  Incidentally, in response to various aspects that can be adopted by the signal processing apparatus of the second embodiment described above, the signal processing method of the second embodiment may also adopt various aspects.

(Embodiment of computer program)
<19>
The computer program according to the first embodiment is a computer program executed by a computer, and recognizes n (however, based on a recognition step for recognizing a cycle of an input signal having periodicity and the cycle recognized by the recognition step. , N is an integer greater than or equal to 1), the characteristic of the input signal for the number of consecutive periods is the display size of the characteristic of the input signal for the number n of consecutive periods and in a direction corresponding to the time axis. A generation process for generating display data for display in a display mode in which the display size along the display size is fixed regardless of the length of n consecutive cycles, and an output process for outputting the display data to a display device; Is executed by the computer.

  According to the computer program of the first embodiment, it is possible to suitably enjoy the same effects as the various effects enjoyed by the signal processing device of the first embodiment described above.

  Incidentally, in response to various aspects that can be adopted by the signal processing apparatus of the first embodiment described above, the computer program of the first embodiment may also adopt various aspects.

<20>
The computer program according to the second embodiment is a computer program executed by a computer, and a recognition step for recognizing a subdivision period obtained by subdividing each cycle of an input signal having periodicity, and the recognition step Based on the subdivision period recognized by, the characteristics of the input signal for m consecutive subdivision periods (where m is an integer equal to or greater than 1) are the same as the characteristics of the m subdivision periods. Display data for display in a display mode in which the display size of the characteristics of the input signal and the display size along the direction corresponding to the time axis is a fixed size regardless of the length of m consecutive subdivision periods The computer is caused to execute a generation process for generating the display data and an output process for outputting the display data to a display device.

  According to the computer program of the second embodiment, it is possible to suitably enjoy the same effects as the various effects enjoyed by the signal processing apparatus of the second embodiment described above.

  Incidentally, in response to various aspects that can be adopted by the signal processing apparatus of the second embodiment described above, the computer program of the second embodiment may also adopt various aspects.

(Embodiment of recording medium)
<21>
The recording medium according to the first embodiment is a recording medium on which a computer program to be executed by a computer is recorded, the recognition step for recognizing the cycle of an input signal having periodicity, and the cycle recognized by the recognition step Based on the above, the characteristic of the input signal for n consecutive periods (where n is an integer of 1 or more) is the display size of the characteristic of the input signal for the n consecutive periods, and A generation process for generating display data for display in a display mode in which the display size along the direction corresponding to the time axis is a fixed size regardless of the length of n consecutive cycles, and the display data is displayed. The computer program which makes the said computer perform the output process output to an apparatus is recorded.

  According to the recording medium of the first embodiment, it is possible to suitably enjoy the same effects as the various effects enjoyed by the signal processing device of the first embodiment described above.

  Incidentally, in response to various aspects that can be adopted by the signal processing apparatus of the first embodiment described above, the recording medium of the first embodiment may also adopt various aspects.

<22>
The recording medium of the second embodiment is a recording medium on which a computer program executed by a computer is recorded, and recognizes a subdivision period obtained by subdividing each period of an input signal having periodicity. Based on the recognition step and the subdivision period recognized by the recognition step, the characteristics of the input signal for m (where m is an integer of 1 or more) continuous subdivision periods A display mode in which the display size of the characteristics of the input signal is equal to the subdivision period and the display size along the direction corresponding to the time axis is a fixed size regardless of the length of m consecutive subdivision periods The computer program which makes the said computer perform the production | generation process which produces | generates the display data for displaying by this and the output process which outputs the said display data to a display apparatus is recorded.

  According to the recording medium of the second embodiment, it is possible to suitably enjoy the same effects as the various effects enjoyed by the signal processing apparatus of the second embodiment described above.

  Incidentally, in response to various aspects that can be adopted by the signal processing apparatus of the second embodiment described above, the recording medium of the second embodiment may also adopt various aspects.

  Such an operation and other advantages of the present embodiment will be further clarified from examples described below.

  As described above, the signal processing apparatus according to the first or second embodiment includes the recognition unit, the generation unit, and the output unit. The signal processing method of the first or second embodiment includes a recognition process, a generation process, and an output process. The computer program of the first or second embodiment causes a computer to execute a recognition process, a generation process, and an output process. The recording medium of the first or second embodiment is a recording medium on which a computer program that causes a computer to execute a recognition process, a generation process, and an output process is recorded. Therefore, the input signal is displayed in a more easily viewable manner.

  Hereinafter, embodiments of a signal processing apparatus and method, a computer program, and a recording medium will be described with reference to the drawings. In the following, it is assumed that a breathing sound signal indicating a breathing sound is used as the input signal. However, another biological sound signal different from the respiratory sound signal may be used as the input signal. Examples of other biological sound signals include, for example, a heart sound signal indicating a heart sound, a pulsation sound signal indicating a sound caused by a pulsation (in other words, a pulse wave), and a sound caused by an activity state of an internal organ officer (for example, Examples include a visceral sound signal indicating intestinal sound due to intestinal movement), a blood flow sound signal indicating sound due to blood flow, and the like. Alternatively, any signal other than the body sound signal (however, an arbitrary signal having periodicity) may be used as the input signal.

(1) Configuration of Signal Processing Device First, the configuration of the signal processing device 10 of this embodiment will be described with reference to FIG. FIG. 1 is a block diagram illustrating a configuration of a signal processing device 10 according to the present embodiment.

  As illustrated in FIG. 1, the signal processing device 10 according to the present exemplary embodiment includes a signal acquisition unit 101, a signal storage unit 102, a period determination unit 113 which is a specific example of “recognition unit”, a signal analysis unit 103, and the like. , A display data generation unit 104 that is a specific example of “recognition unit”, “generation unit”, and “output unit”, and a display unit 105 that is a specific example of “display device”.

  The signal acquisition unit 101 acquires a respiratory sound signal. For example, the signal acquisition unit 101 may directly acquire a respiratory sound signal by directly detecting a respiratory sound of a living body. In this case, the signal acquisition unit 101 may include a respiratory sound sensor that is attached to a living body and detects a respiratory sound of the living body. Such a respiratory sound sensor is typically a microphone (for example, a coil-type microphone, a capacitor-type microphone, a piezoelectric microphone, or the like). However, as long as the respiratory sound sensor can detect the respiratory sound, the respiratory sound sensor may be any type of sensor.

  FIG. 1 shows an example in which the signal processing apparatus 10 includes a signal acquisition unit 101. However, the signal processing apparatus 10 may not include the signal acquisition unit 101. In this case, it is preferable that the signal processing apparatus 10 acquires a respiratory sound signal from the signal acquisition unit 101 arranged outside the signal processing apparatus 10 via a wired or wireless communication line or a wired signal line. .

  The signal storage unit 102 temporarily stores the respiratory sound signal acquired by the signal acquisition unit 101. For this reason, the signal storage unit 102 may include a memory or a buffer. As will be described later, the signal storage unit 102 preferably stores the respiratory sound signals for a predetermined period among the respiratory sound signals sequentially acquired by the signal acquisition unit 101.

  FIG. 1 shows an example in which the signal processing apparatus 10 includes a signal storage unit 102. However, the signal processing apparatus 10 may not include the signal storage unit 102.

  The cycle determination unit 113 performs a predetermined cycle determination process on the respiratory sound signal stored in the signal storage unit 102.

  In the present embodiment, the predetermined cycle determination process may include a process of determining (in other words, specifying or detecting) the cycle of the respiratory sound signal. Specifically, in the predetermined cycle determination process, the amplitude level of the respiratory sound signal is equivalent to one cycle with respect to the respiratory sound signal in which the amplitude level (that is, the characteristic indicating the signal strength) changes while increasing and decreasing periodically. It may include processing for determining that the period required to change only the period of the respiratory sound signal. In other words, considering that the breathing sound signal is an audio signal corresponding to a sound caused by the biological activity of breathing, the predetermined cycle determination process is performed for one breath (one breath among a plurality of repeated breaths ( That is, it may include a process for determining that a period required for continuous exhalation and inspiration is a cycle of the breathing sound signal.

  In addition, in the predetermined cycle determination process executed for any biological sound signal other than the respiratory sound signal, the period required for one activity among the biological activities repeatedly performed a plurality of times is the cycle of the biological sound signal. It may include processing for determining that there is. For example, the predetermined cycle determination process is a process of determining that a period required for one beat of a heart beat repeatedly performed is a period of a heart sound signal, a pulsation sound signal, or a blood flow sound signal. May be included. The period determination process executed for other biological sound signals or input signals may also include a process for determining the period in the same manner.

  Furthermore, in the present embodiment, the predetermined cycle determination process may include a process of determining a subdivision period obtained by subdividing the period of the respiratory sound signal. For example, the predetermined cycle determination process may include a process of determining a subdivision period obtained by subdividing the cycle of the respiratory sound signal according to the tendency of change in the amplitude level of the respiratory sound signal. Specifically, one breath, which is an activity of the living body, is composed of one exhalation and one inspiration with different tendencies of change in amplitude level. Therefore, the predetermined cycle determination process is a process for determining an expiration period (that is, a period in which expiration is performed) and an inspiration period (that is, a period in which inspiration is performed) in each period of the respiratory sound signal. May be included.

  In addition, the predetermined | prescribed period determination process performed with respect to arbitrary biological sound signals other than a respiratory sound signal changes one activity of the biological activity performed repeatedly several times into the aspect of the said one activity. A process for determining a subdivision period obtained by subdividing according to the above may be included. For example, one heart pulsation, which is a biological activity, is composed of one ventricular contraction and one ventricular dilation in different modes of activity. For this reason, the predetermined period determination process executed for the heart sound signal, the pulsation sound signal, or the blood flow sound signal is performed during the period during which the ventricle is contracted and the ventricle is expanded in each period of the biological sound signal. It may include a process for determining a period of time. The period determination process executed for other biological sound signals or input signals may also include a process for determining the segmentation period in the same manner.

  FIG. 1 shows an example in which the signal processing apparatus 10 includes a period determination unit 113. However, the signal processing device 10 may not include the period determination unit 113. In this case, the signal processing device 10 is located outside the signal processing device 10 via a wired or wireless communication line or a wired signal line from the period determination unit 113 arranged outside the signal processing device 10. It is preferable to acquire the result of the cycle determination process executed by the cycle determination unit 113.

  The signal analysis unit 103 performs predetermined analysis processing on the respiratory sound signal stored in the signal storage unit 102. In the present embodiment, the predetermined analysis processing includes analysis processing for separating the respiratory sound signal into a plurality of types of signal components that can be distinguished from each other. In other words, the predetermined analysis processing includes analysis processing for extracting at least one of a plurality of types of signal components that can be distinguished from each other from the respiratory sound signal. In other words, the predetermined analysis process includes an analysis process for analyzing what kind of signal component is included in the respiratory sound signal.

  Specifically, for example, the predetermined analysis process may include an analysis process for separating a respiratory sound signal into a signal component corresponding to a normal sound and a signal component corresponding to an abnormal sound different from the normal sound. Good. In other words, for example, the predetermined analysis process may include an analysis process for extracting at least one of a signal component corresponding to a normal sound and a signal component corresponding to an abnormal sound from the respiratory sound signal.

  Alternatively, for example, the predetermined analysis process may include an analysis process for separating the respiratory sound signal into a plurality of types of signal components corresponding to a plurality of types of normal sounds that can be distinguished from each other. In other words, for example, the predetermined analysis process may include an analysis process for extracting at least one of a plurality of types of signal components corresponding to a plurality of types of normal sounds that can be distinguished from each other from the respiratory sound signal. .

  Alternatively, for example, the predetermined analysis process may include an analysis process for separating the respiratory sound signal into a plurality of types of signal components corresponding to a plurality of types of abnormal sounds that can be distinguished from each other. In other words, for example, the predetermined analysis process may include an analysis process for extracting at least one of a plurality of types of signal components corresponding to a plurality of types of abnormal sounds that can be distinguished from each other from the respiratory sound signal. .

  The signal analysis unit 103 outputs the result of the analysis processing (for example, information that can specify a plurality of types of signal components themselves) to the display data generation unit 104.

  FIG. 1 shows an example in which the signal processing apparatus 10 includes a signal analysis unit 103. However, the signal processing apparatus 10 may not include the signal analysis unit 103. In this case, the signal processing device 10 is located outside the signal processing device 10 from the signal analysis unit 103 disposed outside the signal processing device 10 via a wired or wireless communication line or a wired signal line. It is preferable to acquire the result of the analysis process executed by the signal analysis unit 103.

  Based on the results of the analysis processing executed by the signal analysis unit 103 and the cycle determination processing executed by the cycle determination unit 113, the display data generation unit 104 has characteristics of each of a plurality of types of signal components constituting the respiratory sound signal (for example, Display data (for example, an image signal) for displaying on the display unit 105 the amplitude level corresponding to the signal intensity). In other words, the display data generation unit 104 displays display data for displaying on the display unit 105 some display object capable of visually specifying the characteristics of each of a plurality of types of signal components constituting the respiratory sound signal. Is generated. Note that the display object may be any display object as long as the characteristics of the respiratory sound signal can be visually identified. For example, the display object may be a display object including text (for example, characters and numerical values) that visually specifies the characteristics of the respiratory sound signal. Alternatively, for example, the display object may be a display object including a graphic (for example, a graph or a chart) that visually specifies the characteristics of the respiratory sound signal.

  In the present embodiment, the display data generation unit 104 may generate display data for displaying the characteristics of signal components for n periods (where n is an integer of 1 or more) that are continuous in time. . In particular, the display data generation unit 104 displays the display size of characteristics of signal components for n consecutive periods in time (specifically, the display size along the direction corresponding to the time axis, and so on). It is preferable to generate display data for display so as to have a fixed size. That is, the display data generation unit 104 sets the display size of the characteristics of the signal components for n consecutive periods in time to a fixed size regardless of the time length of the n consecutive periods. It is preferable to generate display data.

  Furthermore, in the present embodiment, the display data generation unit 104 generates display data for displaying the characteristics of signal components for m subdivision periods that are continuous in time (where m is an integer of 1 or more). May be. In particular, the display data generation unit 104 displays the display size of the characteristics of signal components for m subdivided periods that are temporally continuous (specifically, the display size along the direction corresponding to the time axis, It is preferable to generate the display data so that the same is the fixed size. In other words, the display data generation unit 104 fixes the display size of the characteristics of the signal components for m continuous subdivision periods regardless of the time lengths of the m subdivided periods continuous in time. It is preferable to generate display data so as to have a size.

  In addition, the display data generation unit 104 outputs the generated display data to the display unit 105.

  The period determination unit 113, the signal analysis unit 103, and the display data generation unit 104 are processing blocks that are logically realized on a CPU (Central Processing Unit). However, the period determination unit 113, the signal analysis unit 103, and the display data generation unit 104 may each be a processing circuit physically realized by a semiconductor chip or the like.

  The display unit 105 is a display device that performs display processing based on the display data generated by the display data generation unit 104. As a result, the display unit 105 displays on the display screen of the display unit 105 the characteristics of each of a plurality of types of signal components constituting the respiratory sound signal.

  FIG. 1 shows an example in which the signal processing apparatus 10 includes a display unit 105. However, the signal processing apparatus 10 may not include the display unit 105. In this case, the signal processing device 10 generates display data generated by the display data generation unit 104 via a wired or wireless communication line or a wired signal line with respect to the display unit 105 located outside the signal processing device 10. It is preferable to transfer.

(2) Operation of Signal Processing Device 10 of the Present Example Next, the operation of the signal processing device 10 of the present example will be described with reference to FIGS. 2 to 11. FIG. 2 is a flowchart showing the operation flow of the signal processing apparatus 10 of the present embodiment. FIG. 3 is a schematic diagram illustrating an example of how the signal acquisition unit 101 is attached to the living body, and a graph illustrating the waveform of the respiratory sound signal on the time axis. FIG. 4 is a schematic diagram illustrating an example of an operation in which the signal storage unit 102 stores a respiratory sound signal. FIG. 5 is a classification chart showing the types of respiratory sounds. FIG. 6 shows five types of breathing sounds (alveolar breathing sounds, low-pitched continuous rales (similar sounds), high-pitched continuous rales (flute sounds), fine intermittent rales (haircut sounds), and rough sounds It is a graph which shows on the time-axis the waveform of five types of signal components equivalent to a discontinuous ra sound (water bubble sound). FIG. 7 is a graph showing a first aspect of the cycle determination process together with the waveform of the respiratory sound signal. FIG. 8 is a graph showing the second mode of the period determination process together with the waveform of the respiratory sound signal. FIG. 9 is a plan view illustrating an example of a display mode of a signal component (breathing sound signal) realized by display data generated by the display data generation unit 104. FIG. 10 is a schematic diagram illustrating an example of conversion processing for setting the display size of the alveolar respiratory sound component for one cycle (specifically, the display size along the time axis) to a fixed size. In FIG. 11, the display size of the amplitude level of the signal component for one cycle does not become a fixed size (that is, the display size of the amplitude level of the signal component for one cycle varies according to the length of one cycle). It is a top view which shows an example of an aspect.

  As shown in FIG. 2, the signal acquisition unit 101 first acquires a respiratory sound signal (step S101). For example, as shown in FIG. 3A, the signal acquisition unit 101 may be attached to the body surface of the living body (in the example shown in FIG. 3A, the body surface near the left breast). At this time, the mounting position of the signal acquisition unit 101 may be fixed. Alternatively, in consideration of appropriately changing the position of the stethoscope when the medical staff auscultates, the mounting position of the signal acquisition unit 101 may be changed as appropriate during the acquisition of the respiratory sound signal. . As a result, the signal acquisition unit 101 acquires a respiratory sound signal. At this time, the signal acquisition unit 101 may acquire a respiratory sound signal periodically according to a predetermined sampling frequency. That is, the signal acquisition unit 101 may periodically acquire a sample value of the respiratory sound signal. However, the signal acquisition unit 101 may acquire a respiratory sound signal aperiodically or continuously. As a result, the signal acquisition unit 101 can acquire a respiratory sound signal specified as a waveform on the time axis shown in FIG.

  As shown in FIG. 3B, considering that the respiration of the living body is a repetition of inspiration (that is, intake of air into the lung) and expiration (that is, exhalation of air from the lung), It can be said that the respiratory sound signal is a signal having periodicity. One cycle of the breathing sound signal is a period obtained by adding the inspiration period (that is, the period during which inspiration is performed) and the expiration period following the inspiration period (that is, the period during which expiration is performed). Needless to say, the period of the respiratory sound signal may vary with time.

  In parallel with the acquisition of the respiratory sound signal by the signal acquisition unit 101, the signal storage unit 102 temporarily stores the respiratory sound signal acquired by the signal acquisition unit 101 (step S102). At this time, the signal storage unit 102 has a larger size of the respiratory sound signal of the size necessary for analysis processing executed by the signal analysis unit 103 described later and the size required for cycle determination processing executed by the cycle determination unit 113. Is preferably stored temporarily. In this embodiment, it is assumed that the size of the respiratory sound signal necessary for the analysis processing executed by the signal analysis unit 103 is “1 second”. On the other hand, in this embodiment, the size required for the cycle determination process executed by the cycle determination unit 113 is 20 to 25 seconds (in other words, the size of the respiratory sound signal for five cycles, and the length of one cycle. Is about 4 to 5 seconds (4 to 5 seconds) × 5 cycles = 20 to 25 seconds). Therefore, in this case, it is preferable that the signal storage unit 102 temporarily stores at least the latest (in other words, the latest) 20 seconds of respiratory sound signals. In order to temporarily store the respiratory sound signal for the latest 20 seconds, it is preferable that the signal storage unit 102 includes a ring buffer. However, the size of the respiratory sound signal necessary for the analysis processing executed by the signal analysis unit 103 may be any time other than 1 second. Similarly, the size of the respiratory sound signal necessary for the cycle determination process executed by the signal analysis unit 103 may be an arbitrary time other than 20 seconds to 25 seconds.

  When a heart sound signal is used instead of the respiratory sound signal, the size required for the cycle determination process executed by the cycle determination unit 113 is, for example, 4 seconds to 5 seconds (in other words, the heart sound signal for 5 cycles). For a heart sound signal in which the length of one cycle is approximately 0.8 seconds to 1 second, 0.8 seconds to 1 second × 5 cycles = 4 seconds to 5 seconds). However, the size of the respiratory sound signal necessary for the cycle determination process executed by the signal analysis unit 103 may be any time other than 4 seconds to 5 seconds.

  For example, when the signal acquisition unit 101 acquires a respiratory sound signal in accordance with a sampling frequency of 44100 Hz, the signal storage unit 102 temporarily stores 44100 × 20 seconds = 882000 respiratory sound signal sample values. Remember. More specifically, as shown in FIG. 4, the signal storage unit 102 is acquired at the sample value S (t) of the respiratory sound signal acquired at the latest time (t) and at the time (t−1). The sample value S (t-1) of the respiratory sound signal, the sample value S (t-2) of the respiratory sound signal acquired at time (t-2), ..., at time (t-881999) The acquired sample value S (t-881999) of the respiratory sound signal is temporarily stored.

  In parallel with the acquisition of the respiratory sound signal by the signal acquisition unit 101, the signal analysis unit 103 performs a predetermined analysis process on the respiratory sound signal stored in the signal storage unit 102 (step S103a). That is, the signal analysis unit 103 performs an analysis process on the respiratory sound signal stored in the signal storage unit 102 to separate the respiratory sound signal into a plurality of types of signal components. However, the signal analysis unit 103 does not have to execute analysis processing for separating the respiratory sound signal into a plurality of types of signal components.

  Here, the types of breathing sounds will be described with reference to FIG. As shown in FIG. 5, breathing sounds in a broad sense (that is, lung sounds) are classified into a breathing sound in a narrow sense and a sub-noise that is an example of an abnormal sound. Narrowly defined respiratory sounds are classified into normal respiratory sounds, which are examples of normal sounds, and abnormal respiratory sounds, which are examples of abnormal sounds. Normal respiratory sounds are classified into alveolar respiratory sounds, bronchial respiratory sounds, bronchoalveolar respiratory sounds, and tracheal respiratory sounds. Abnormal breathing sounds are classified into breathing sounds caused by attenuation / disappearance, breathing sounds caused by enhancement, breathing sounds caused by exhaled breath, breathing sounds caused by bronchial breathing, and tracheal stenosis sounds. Is done. The sub-noise is classified into a ra sound and other sounds. The rales are classified into continuous rales and intermittent rales. The continuous rales are classified into low-pitched continuous rales (sounds), high-pitched continuous rales (flute sounds), and scwalks (inspiratory continuous rales). Intermittent rales are classified into fine intermittent rales (haircut sounds) and coarse intermittent rales (water bubbles). Other sounds are classified into pleural friction sounds and pulmonary vascular noise.

  In this embodiment, the signal analysis unit 103 uses the respiratory sound signal as an example of a signal component corresponding to an alveolar respiratory sound (hereinafter referred to as “alveolar respiratory sound component”) that is an example of a normal sound and an abnormal sound. Corresponding to the signal component (hereinafter referred to as “sound-like sound component”) corresponding to the low-pitched continuous ra sound (similar sound) and the high-sounding continuous ra sound (flute sound) as an example of the abnormal sound A signal component (hereinafter referred to as a “flute sound component”) and a signal component (hereinafter referred to as a “twist sound component”) corresponding to a fine intermittent rale (haircut sound) which is an example of an abnormal sound. Then, an analysis process is performed to separate into a signal component (hereinafter referred to as “water bubble sound component”) corresponding to a rough intermittent sound (water bubble sound) that is an example of an abnormal sound. In other words, the signal analysis unit 103 performs an analysis process of extracting at least one of the alveolar respiratory sound component, the analogy sound component, the whistle sound component, the hair-hair sound component, and the water bubble sound component from the respiratory sound signal. . The first graph in FIG. 6 shows an example of the alveolar respiratory sound component. The second graph in FIG. 6 shows an example of the analog sound component. The third graph in FIG. 6 shows an example of a whistle voice component. The graph in the fourth row in FIG. 6 shows an example of the haircut sound component. The fifth graph in FIG. 6 shows an example of the water bubble sound component.

  The signal analysis unit 103 may separate the respiratory sound signal into an alveolar respiratory sound component, an analogy sound component, a whistle sound component, a hairpin sound component, and a water bubble sound component from the following viewpoints. .

  Specifically, the frequency spectrum shape of the signal components corresponding to the alveolar respiratory sound component and the intermittent rar sound (that is, the hair hair sound component and the water bubble sound component) is relatively wideband and relatively smooth. On the other hand, there is a difference that the shape of the frequency spectrum of the signal component (that is, the analog sound component and the whistle sound component) corresponding to the continuous rar is relatively narrow band and relatively steep. Therefore, the signal analysis unit 103 pays attention to such a difference in the frequency spectrum shape, so that the respiratory sound signal is different from the signal component corresponding to the continuous ra sound and the signal component corresponding to the continuous ra sound. You may isolate | separate into a signal component (namely, the signal component corresponded to an alveolar respiration sound component and an intermittent rale).

  Further, there is a difference that the frequency of the whistle sound component is relatively high while the frequency of the analog sound component is relatively low. Therefore, the signal analysis unit 103 may separate the signal component corresponding to the continuous rale into an analog sound component and a whistle sound component by paying attention to such a difference in frequency.

  Further, the alveolar respiratory sound component is a signal component that is continuous in time (that is, continuous), whereas the signal component corresponding to the intermittent rar is a pulsed signal component that is intermittent in time. There is. Accordingly, the signal analysis unit 103 pays attention to such a difference in the distribution of the signal components on the time axis, and thereby converts a signal component different from the signal component corresponding to the continuous rales into an alveolar respiratory sound component. You may isolate | separate into the signal component corresponded to an intermittent rarity.

  In addition, there is a difference that the frequency of the frizzy sound component is relatively high while the frequency of the water bubble sound component is relatively low. Therefore, the signal analysis unit 103 may separate the signal component corresponding to the intermittent rattling sound into the water bubble sound component and the haircut sound component by paying attention to such a frequency difference.

  Note that the above-described method relating to analysis processing for separating a respiratory sound signal into five types of signal components (that is, an alveolar respiratory sound component, an analogy sound component, a whistle sound component, a haircut sound component, and a water bubble sound component) is merely an example. It is. Therefore, the signal analysis unit 103 may execute analysis processing for separating the respiratory sound signal into five types of signal components by other methods. Note that methods for separating a respiratory sound signal into a plurality of types of signal components (or extracting a specific type of signal component from the respiratory sound signal) are disclosed in, for example, JP-T-2004-531309 and JP-A-2005-66045. Gazettes, Special Tables 2001-505085, Special Tables 2007-508899, “Sparse representation of lung sound signals and application to intermittent sound separation, Sakai / Satomoto / Kiyan / Miyahara, Nagasaki University National Studies Report Vol. 41, No. 76 ”and the like. Therefore, the signal analysis unit 103 may separate the respiratory sound signal into a plurality of types of signal components using the methods disclosed in these documents.

  Further, the signal analysis unit 103 separates the respiratory sound signal into arbitrary plural types of signal components in addition to or instead of the analysis processing for separating the respiratory sound signal into the above-described five types of signal components (or the respiratory sound). An analysis process (extracting one or more arbitrary signal components from the signal) may be executed.

  Note that the respiratory sound signal that is the target of the analysis processing by the signal analysis unit 103 typically has a high possibility of always including an alveolar respiratory sound component. Because, as long as the living body is breathing, the breathing sound should contain alveolar breathing sound, which is an example of normal sound, regardless of whether or not abnormal sound is included. It is. On the other hand, the respiratory sound signal that is the target of the analysis processing by the signal analysis unit 103 may include all of the five types of signal components. Alternatively, the respiratory sound signal that is the target of analysis processing by the signal analysis unit 103 may include only a part of the five types of signal components. Alternatively, the respiratory sound signal that is the target of analysis processing by the signal analysis unit 103 may not include all of the five types of signal components. In any case, the signal analysis unit 103 can acquire each of the five types of signal components by executing an analysis process that separates the respiratory sound signal into the above-described five types of signal components. For example, the signal analysis unit 103 can acquire the signal component included in the respiratory sound signal by executing the analysis process, and the amplitude level of the signal component not included in the respiratory sound signal is zero. As a signal component.

  In parallel with the analysis process of the respiratory sound signal by the signal analysis unit 103, the cycle determination unit 113 performs a predetermined cycle determination process on the respiratory sound signal stored in the signal storage unit 102 (step S113). That is, the signal analysis unit 103 determines at least one of the period of the respiratory sound signal and the subdivision period (that is, the expiration period and the inspiration period) with respect to the respiratory sound signal stored in the signal storage unit 102. Execute the period determination process.

  The period determination unit 113 may determine at least one of the period of the respiratory sound signal and the subdivision period (that is, the expiration period and the inspiration period) from the following viewpoints.

  Specifically, as shown in FIG. 7, the cycle determination unit 113 is configured such that a silent portion where the absolute value of the amplitude level of the respiratory sound signal is equal to or less than a predetermined threshold A is at a boundary between at least one of the cycle and the segmentation period. By considering it as being, at least one of the period of the respiratory sound signal and the subdivision period (that is, the expiration period and the inspiration period) may be determined. In the example shown in FIG. 7, the cycle determination unit 113 determines the subdivision period (that is, the expiration period and the inspiration period) of the respiratory sound signal by regarding the silent part as the boundary of the subdivision period. Yes. However, in consideration of the fact that two consecutive subdivision periods correspond to one cycle, in the example shown in FIG. 7, the cycle determination unit 113 is one of the two silent units. It can be said that the period of the breathing sound signal is determined by regarding that is the boundary of the period.

  In addition, when it is considered that a silence part is a boundary of a period or a subdivision period, it is preferable that the time interval between the silence parts used as the said boundary is a fixed period or more. That is, it is preferable that the period determination unit 113 considers that one of the two silence parts whose time interval is less than a certain period is not a boundary of the period or the subdivision period. As a result, even if an abnormally small instantaneous value is mixed in with the respiratory sound signal, the period determining unit 113 can preferably determine at least one of the period and the subdivided period based on the silent part. it can.

  Alternatively, as illustrated in FIGS. 8A and 8B, the cycle determination unit 113 performs the period of the respiratory sound signal and the subdivision period (that is, the expiration period) based on the similarity of the waveform of the respiratory sound signal. And the intake period) may be determined. Specifically, when a waveform having a high degree of similarity (for example, relatively high or higher than a predetermined frequency) is repeated, the period determination unit 113 determines the period in which each waveform appears as a period and a subdivision. You may determine with it being at least one of the periods. For example, in the example illustrated in FIG. 8A, the period determination unit 113 determines that the waveform A, the waveform A ′, and the waveform A ″ are similar (that is, the degree of similarity is high) and the determination. Based on the result, it is determined that the period in which each of the waveform A, the waveform A ′, and the waveform A ″ appears is one intake period. Similarly, in the example illustrated in FIG. 8A, the period determination unit 113 determines that the waveform B and the waveform B ′ are similar (that is, has a high degree of similarity), and based on the determination result. The period in which each of the waveform B and the waveform B ′ appears is determined as one expiration period. Alternatively, in the example illustrated in FIG. 8B, the period determination unit 113 determines that the waveform a, the waveform a ′, and the waveform a ″ are similar (that is, the degree of similarity is high) and the determination. Based on the results, it is determined that the period in which each of the waveform a, the waveform a ′, and the waveform a ″ appears is one cycle.

  Thereafter, the display data generation unit 104, based on the result of the analysis process executed by the signal analysis unit 103 and the result of the cycle determination process executed by the cycle determination unit 113, each of a plurality of types of signal components constituting the respiratory sound signal. Display data for displaying the above characteristics on the display unit 105 is generated (step S104). The display data is data indicating a display object displayed by the display unit 105. Such display data includes, for example, at least text (for example, characters and numerical values) and graphics (for example, graphs and charts) that visually specify the amplitude level of each signal component constituting the respiratory sound signal. Data corresponding to an image signal indicating one (or any signal having a format different from the image signal) may be used.

  At this time, as described above, the display data generation unit 104 may generate the display data so that the display size of the characteristics of the signal components for n consecutive periods in time is a fixed size. Alternatively, the display data generation unit 104 may generate the display data so that the display size of the characteristics of the signal components for m continuous subdivision periods is a fixed size.

  In the following description, the display data generation unit 104 will be described using an example in which display data is generated so that the display size of the characteristic of the signal component for one cycle becomes a fixed size. That is, the display data generation unit 104 (i) the display size of the characteristics of the alveolar respiratory sound component for one cycle becomes the first size fixed regardless of the variation of the cycle of the respiratory sound signal, and (ii) The display size of the characteristics of the analog sound component for one cycle is fixed regardless of the fluctuation of the cycle of the respiratory sound signal (however, the second size may be the same as the first size) (Iii) The third size (however, the third size) in which the display size of the characteristics of the whistle sound component for one cycle is fixed regardless of the variation of the cycle of the respiratory sound signal. (Iv) may be the same as or different from at least one of the first size and the second size), and (iv) the display size of the characteristics of the hair component for one cycle is breathing Fixed fourth size regardless of fluctuations in the period of the sound signal However, the fourth size may be the same as or different from at least one of the first size to the third size), and (v) display of characteristics of the water bubble sound component for one cycle The fifth size is fixed regardless of the fluctuation of the cycle of the respiratory sound signal (however, the fifth size may be the same as or different from at least one of the first size to the fourth size) Display data should be generated so that it may be.

  However, the display data generation unit 104 may generate the display data so that the display size of the characteristics of the signal components for two or more cycles that are temporally continuous becomes a fixed size. Alternatively, the display data generation unit 104 may generate display data such that the display size of the signal component characteristics for one subdivision period is a fixed size. Alternatively, the display data generation unit 104 may generate the display data so that the display size of the characteristics of the signal components for two or more subdivision periods that are temporally continuous becomes a fixed size.

  Further, in the following description, the description proceeds by using an example in which the characteristic of the signal component displayed on the display unit 105 is an amplitude level (that is, a characteristic indicating the signal strength). However, it goes without saying that the characteristic of the signal component may be a characteristic different from the amplitude level (in other words, an index (variable) capable of specifying the state of the signal component).

  In the following description, the display data generation unit 104 includes five types of signal components included in the respiratory sound signal (that is, the alveolar respiratory sound component, the analogy sound component, the whistle sound component, the haircut sound component, and the water bubble sound) The description will be given using an example of generating display data for displaying each characteristic of the component. However, the display data generation unit 104 may generate display data for displaying the characteristics of the respiratory sound signal itself. That is, the display data generation unit 104 has characteristics of respiratory sound signals for one period (or two or more periods continuous in time or one or two or more subdivision periods continuous in time). The display data may be generated so that the display size of the image becomes a fixed size. When the display data generation unit 104 generates display data for displaying the characteristics of the respiratory sound signal itself, the signal analysis unit 103 does not have to execute a predetermined analysis process.

  Here, referring to FIG. 9, a display mode realized by display data generated by the display data generation unit 104 (that is, a display mode in which the display size of the amplitude level of the signal component for one period is a fixed size). An example will be described.

  As shown in FIG. 9, in this embodiment, the amplitude level of the signal component for one cycle may be displayed using a pie chart whose circumferential direction corresponds to the time axis. The pie chart has a plurality of arc-shaped unit display portions D (k (where k is 1 or more and indicates the number of unit display portions) each having the same shape and arranged along the circumferential direction. It may contain any integer)) that: The display mode (for example, contrast, brightness, brightness, hue, saturation, etc.) of the plurality of arc-shaped unit display portions D (k) changes according to the amplitude level of the signal component for one cycle. Is preferred.

  Here, considering that one cycle includes one expiration period and one expiration period, the plurality of arc-shaped unit display portions D (k) may be distinguished from the following viewpoints. Specifically, among the plurality of arc-shaped unit display portions D (k), the lower half unit display portion (that is, unit display portion D (1) to unit display portion D (N / 2)) is one cycle. May be used as a unit display portion D (k) for displaying the amplitude level of the signal component in the inspiratory period. On the other hand, among the plurality of arc-shaped unit display portions D (k), the lower half unit display portion (that is, the unit display portion D ((N / 2) +1) to the unit display portion D (N)) is 1 It may be used as a unit display portion D (k) for displaying the amplitude level of the signal component in the expiration period of the cycle.

  In this case, the display of the amplitude level of the signal component for one cycle may be sequentially performed from the unit display portion D (1) toward the unit display portion D (N). In other words, the amplitude level of the signal component for one cycle is clockwise with the passage of time with the unit display portion D (1) as the display start position and the unit display portion D (N) as the display end position. May be displayed sequentially.

  After the display of the amplitude level of the signal component for one cycle is completed, the display of the amplitude level of the signal component for the next cycle may be newly started. In this case, after all the display of the amplitude level of the signal component for the previous one cycle is once erased (for example, after the display screen of the display unit 105 is reset to the black level), the signal component for the next one cycle. The display of the amplitude level may be newly started. Alternatively, the amplitude level of the signal component for the next cycle is gradually overwritten by the display of the amplitude level of the signal component for the next cycle. May be newly started.

  In the present embodiment, as described above, the display size of the amplitude level of the signal component for one period is a fixed size. Therefore, as shown in FIG. 9, the display size of the amplitude level of the signal component for one cycle having the first time length (for example, 4 seconds) (in the example shown in FIG. (Length) is the same as the display size of the amplitude level of the signal component for one period having a second time length (for example, 5 seconds) different from the first time length. That is, in this embodiment, even if the cycle of the respiratory sound signal varies, the circumference of the pie chart does not change. In consideration of the fact that the circumference of the pie chart substantially depends on the number of unit display portions D (k), in this embodiment, even when the cycle of the respiratory sound signal varies. It can also be said that the size and number of the unit display portions D (k) constituting the pie chart do not change.

  In order to generate display data that realizes such a display mode, the display data generation unit 104 performs a conversion process of compressing (or expanding) each signal component constituting the respiratory sound signal along the time axis. May be.

  Specifically, as shown in FIG. 10, it is assumed that the number of sample values Sa of signal components for one cycle (in the example shown in FIG. 10, alveolar respiratory sound components) is M. That is, it is assumed that the alveolar respiratory sound component for one cycle is composed of the sample value Sa (1) to the sample value Sa (M). In this case, the display data generation unit 104 converts the M sample values Sa into N sample values Sa ′ equal to the number of unit display area portions D (k). For example, the display data generation unit 104 classifies the M sample values Sa into M / N sample values Sa and calculates an average value Sa ′ of the M / N sample values Sa. The M sample values Sa may be converted into N sample values Sa ′. More specifically, the display data generation unit 104 may convert M sample values Sa into N sample values Sa ′ using Equation 1 below. As a result, the amplitude level indicated by the converted N sample values Sa ′ (k) is displayed in the N unit display areas D (k).

  Needless to say, similar conversion processing may be performed not only on the alveolar respiratory sound component but also on other signal components.

  Moreover, the conversion process mentioned above is an example to the last. Therefore, the display data generation unit 104 may perform an arbitrary conversion process for converting M sample values Sa into N sample values Sa ′ that is the same as the number of unit display region portions D (k). Alternatively, the display data generation unit 104 may perform an arbitrary conversion process that can realize displaying the amplitude levels indicated by the M sample values Sa in the N unit display area portions D (N). Good.

  Thereafter, display data is generated. The display data generation unit 104 outputs the generated display data to the display unit 105 as appropriate.

  In parallel with the generation of display data by the display data generation unit 104, the display unit 105 performs a display process based on the display data generated by the display data generation unit 104 (step S105). As a result, the display unit 105 displays the amplitude levels of the five types of signal components using the pie chart shown in FIG. That is, the display unit 105 sets the amplitude levels of the five types of signal components so that the display sizes of the five types of signal components (that is, the display sizes along the direction corresponding to the time axis) are fixed sizes. To display.

  The operations from step S101 to step S105 described above are repeated until the operation of the signal processing device (10) is completed (step S106). At this time, when the operation from step S101 to step S105 is repeated, each operation from step S101 to step S105 is preferably performed periodically, aperiodically, or continuously. That is, each operation from step S101 to step S105 is preferably performed in real time or dynamically.

  Here, in describing the technical effect of the signal processing apparatus 10 of the present embodiment, it will be described in comparison with the signal processing apparatus of the comparative example. The signal processing apparatus of the comparative example displays the amplitude level of the signal component for one cycle in a display mode in which the display size of the amplitude level of the signal component for one cycle varies according to the time length of one cycle. Generate display data. As shown in FIGS. 11A and 11B, the display unit that performs display processing based on display data generated by the signal processing device of the comparative example sets the amplitude level of the signal component for one cycle to one cycle. The display size of the amplitude level of the minute signal component is displayed in a display mode that varies according to the time length of one cycle. As a result, in the comparative example, when the cycle of the respiratory sound signal varies, the display size of the amplitude level of the signal component for one cycle is along the direction corresponding to the time axis (circumferential direction in the example shown in FIG. 11). Will fluctuate. Specifically, as shown in FIG. 11A, the display size of the amplitude level of the signal component for one cycle corresponding to the first time length (for example, 4.0 seconds) is “A”. . On the other hand, the display size of the amplitude level of the signal component for one period corresponding to the second time length (for example, 4.5 seconds) longer than the first time length is shorter than “B”. " Thus, when the display size of the amplitude level of the signal component for one cycle changes, a characteristic waveform of the signal component for one cycle (in the example shown in FIG. 11, from waveform # 1 to waveform # 3). )) Appears (the rotation phase position in the example shown in FIG. 11) may fluctuate. That is, when a characteristic waveform of signal components for one period is originally displayed at the same display position, the characteristic waveform is assumed to be easily recognized (for example, easy to compare). Then, at a certain timing, a characteristic waveform is displayed at the first display position as shown in FIG. 11A, and at another subsequent timing, a characteristic waveform as shown in FIG. It is displayed at a second display position different from the display position.

  However, in this embodiment, even if the cycle of the respiratory sound signal fluctuates, as shown in FIG. 9, the display size of the amplitude level of the signal component for one cycle does not fluctuate. That is, even if the cycle of the respiratory sound signal varies, the display size of the amplitude level of the signal component for one cycle varies along the direction corresponding to the time axis (circumferential direction in the example shown in FIG. 9). There is nothing. Specifically, the display size of the amplitude level of the signal component for one cycle corresponding to the first time length (for example, 4 seconds) is a second time length (for example, 5 times) different from the first time length. The display size of the amplitude level of the signal component for one cycle corresponding to (second) is the same. Since the amplitude level display size of the signal component for one cycle is a fixed size in this way, as shown in FIG. 9, the display position where the characteristic waveform of the signal component for one cycle appears is the respiratory sound. There is little or no fluctuation due to fluctuations in the signal period. That is, in this embodiment, the characteristic waveform of the signal components for one cycle is displayed at the same or substantially the same display position (or is easily displayed), so the display unit 105 is observed. An observer (for example, a medical worker such as a doctor) can appropriately recognize the amplitude level of the signal component.

  In addition, the display mode of the amplitude level of the signal component which comprises the respiratory sound signal shown in FIG. 9 is an example to the last. Therefore, the display data generation unit 104 may generate display data for displaying the amplitude level of the signal component constituting the respiratory sound signal using a display object different from the pie chart shown in FIG. Hereinafter, an example of a display mode for displaying the amplitude level of the signal component constituting the respiratory sound signal using a display object different from the pie chart shown in FIG. 9 will be described with reference to FIGS. 12 to 14 are plan views illustrating examples of display modes for displaying the amplitude levels of the signal components constituting the respiratory sound signal using display objects different from the pie chart illustrated in FIG. 9.

  For example, as shown in FIG. 12, a circular graph in which the circumferential direction corresponds to the time axis and the longer the amplitude level of the signal component is, the longer the bar extends along the radial direction is 1 The amplitude level of the signal component for the period may be displayed.

  Alternatively, for example, as illustrated in FIG. 13, the amplitude level of the signal component for one cycle may be displayed using a bar graph in which the horizontal axis direction corresponds to the time axis. The bar graph has a plurality of rectangular unit display portions D (k (where k is one or more and indicates the number of unit display portions) having the same shape and arranged along the horizontal axis direction. It may contain any integer)). The display mode (for example, contrast, brightness, lightness, hue, saturation, etc.) of the plurality of rectangular unit display portions D (k) changes according to the amplitude level of the signal component for one cycle. Is preferred.

  Alternatively, for example, as shown in FIG. 14, a bar graph in which the horizontal axis direction corresponds to the time axis and the longer the amplitude level of the signal component is, the longer the bar extends along the vertical axis direction. The amplitude level of the signal component for one period may be displayed.

  In addition, the present invention can be appropriately changed without departing from the gist or concept of the invention that can be read from the claims and the entire specification, and a signal processing apparatus and method, a computer program, and a recording accompanying such a change. The medium is also included in the technical idea of the present invention.

DESCRIPTION OF SYMBOLS 10 Signal processing apparatus 101 Signal acquisition part 102 Signal storage part 103 Signal analysis part 104 Display data generation part 105 Display part 113 Period determination part

Claims (22)

Recognition means for recognizing the period of the input signal having periodicity;
Based on the period recognized by the recognizing means, the characteristic of the input signal for n consecutive periods (where n is an integer of 1 or more) is obtained from the characteristics of the input signal for the n consecutive periods. Generating means for generating display data for display in a display mode in which the display size of the characteristic and the display size along the direction corresponding to the time axis is a fixed size regardless of the length of n consecutive cycles When,
An output means for outputting the display data to a display device. The said generation | production means produces | generates the said display data by performing the conversion process which compresses or expand | extends the said input signal for the said n continuous period along a time-axis. Signal processing equipment. The characteristic of the input signal for the n consecutive periods is indicated by M (where M is an integer of 1 or more) sample values, and the input for the n consecutive periods is performed. N (where N is an integer greater than or equal to 1 and less than or equal to M) number of region portions whose signal characteristics can each display one sample value and are arranged along the direction corresponding to the time axis The display means generates the display data by performing the conversion process so that an average value of M / N sample values is displayed in each area portion. The signal processing apparatus according to claim 2. The generation means associates a direction from a display start position where the position on the display screen of the display device is fixed to a predetermined display end position where the position on the display screen is fixed to a time axis. On the display screen, the input for the n consecutive periods is started at the display end position after starting the display of the characteristics of the input signal for the n consecutive periods from the display start position. The signal processing apparatus according to any one of claims 1 to 3, wherein the display data is generated so that display of signal characteristics can be terminated. The generating means uses a circular graph in which (i) the circumferential direction is associated with the time axis, and (ii) the display object whose display mode changes according to the characteristics of the input signal extends in the radial direction. The signal processing apparatus according to any one of claims 1 to 4, wherein the display data for displaying characteristics of the input signal for the n consecutive periods is generated. The input signal is a biological sound signal corresponding to a sound caused by biological activity,
6. The signal processing apparatus according to claim 1, wherein the period is a period required for one activity among biological activities performed a plurality of times repeatedly. The input signal is a respiratory sound signal corresponding to a respiratory sound of a living body,
The signal processing device according to any one of claims 1 to 6, wherein the period is a period required for one continuous exhalation and inspiration. The signal processing apparatus according to claim 1, wherein the cycle of the input signal varies with the passage of time. Recognizing means for recognizing a subdivision period obtained by subdividing each period of an input signal having periodicity;
Based on the subdivision period recognized by the recognition means, the characteristics of the input signal for m (where m is an integer of 1 or more) continuous subdivision periods are represented by the m consecutive subdivision periods. The display size of the input signal characteristics for a minute and the display size along the direction corresponding to the time axis is displayed in a display mode in which the display size is fixed regardless of the length of m consecutive subdivision periods Generating means for generating display data of
An output means for outputting the display data to a display device. The said generation means produces | generates the said display data by performing the conversion process which compresses or expand | extends the said input signal for the said m continuous subdivision periods along a time axis. A signal processing device according to 1. The characteristics of the input signal for the m consecutive segmentation periods are indicated by M (where M is an integer of 1 or more) sample values, and the m consecutive segmentation periods Minutes of the input signal, each of which can display one sample value and is arranged along a direction corresponding to the time axis (where N is an integer of 1 or more and M or less) In the case where display is performed using a plurality of area portions, the generation unit performs the conversion process so that an average value of M / N sample values is displayed in each area portion, whereby the display data is displayed. The signal processing apparatus according to claim 10, wherein: The generation means associates a direction from a display start position where the position on the display screen of the display device is fixed to a predetermined display end position where the position on the display screen is fixed to a time axis. On the display screen, the m consecutive subdivision periods are displayed at the display end position after starting the display of the characteristics of the input signal for the m continuous subdivision periods from the display start position. The signal processing apparatus according to any one of claims 9 to 11, wherein the display data is generated so that display of the characteristics of the input signal for a minute can be completed. The generating means uses a circular graph in which (i) the circumferential direction is associated with the time axis, and (ii) the display object whose display mode changes according to the characteristics of the input signal extends in the radial direction. The signal processing apparatus according to any one of claims 9 to 12, wherein the display data for displaying the characteristics of the input signal for the m consecutive subdivision periods is generated. The input signal is a biological sound signal corresponding to a sound caused by biological activity,
The period is a period required for one activity among biological activities performed a plurality of times,
The plurality of subdivided periods are a plurality of subdivided periods obtained by subdividing the one activity according to the mode of the one activity. The signal processing device according to claim 1. The input signal is a biological sound signal corresponding to a respiratory sound of a biological body,
The period is a period required for one continuous exhalation and inspiration,
The signal processing device according to any one of claims 9 to 14, wherein the plurality of subdivided periods include a period during which expiration is performed and a period during which inspiration is performed. The signal processing apparatus according to claim 9, wherein the period of the input signal varies with time. A recognition step for recognizing the period of the input signal having periodicity;
Based on the period recognized by the recognition step, the characteristics of the input signal for n consecutive periods (where n is an integer equal to or greater than 1) are determined as the characteristics of the input signal for the n consecutive periods. A generation step of generating display data for display in a display mode in which a display size of a characteristic and a display size along a direction corresponding to a time axis is a fixed size regardless of the length of n consecutive cycles When,
An output step of outputting the display data to a display device. A recognition step for recognizing a subdivision period obtained by subdividing each cycle of an input signal having periodicity;
Based on the subdivision period recognized by the recognition step, the characteristics of the input signal for m (where m is an integer of 1 or more) continuous subdivision periods are represented by the m continuous subdivision periods. The display size of the input signal characteristics for a minute and the display size along the direction corresponding to the time axis is displayed in a display mode in which the display size is fixed regardless of the length of m consecutive subdivision periods A generation process for generating display data of
An output step of outputting the display data to a display device. A computer program executed by a computer,
A recognition step for recognizing the period of the input signal having periodicity;
Based on the period recognized by the recognition step, the characteristics of the input signal for n consecutive periods (where n is an integer equal to or greater than 1) are determined as the characteristics of the input signal for the n consecutive periods. A generation step of generating display data for display in a display mode in which a display size of a characteristic and a display size along a direction corresponding to a time axis is a fixed size regardless of the length of n consecutive cycles When,
A computer program causing the computer to execute an output step of outputting the display data to a display device. A computer program executed by a computer,
A recognition step for recognizing a subdivision period obtained by subdividing each cycle of an input signal having periodicity;
Based on the subdivision period recognized by the recognition step, the characteristics of the input signal for m (where m is an integer of 1 or more) continuous subdivision periods are represented by the m continuous subdivision periods. The display size of the input signal characteristics for a minute and the display size along the direction corresponding to the time axis is displayed in a display mode in which the display size is fixed regardless of the length of m consecutive subdivision periods A generation process for generating display data of
A computer program causing the computer to execute an output step of outputting the display data to a display device. A recording medium on which a computer program to be executed by a computer is recorded,
A recognition step for recognizing the period of the input signal having periodicity;
Based on the period recognized by the recognition step, the characteristics of the input signal for n consecutive periods (where n is an integer equal to or greater than 1) are determined as the characteristics of the input signal for the n consecutive periods. A generation step of generating display data for display in a display mode in which a display size of a characteristic and a display size along a direction corresponding to a time axis is a fixed size regardless of the length of n consecutive cycles When,
A recording medium in which a computer program for causing the computer to execute an output step of outputting the display data to a display device is recorded. A recording medium on which a computer program to be executed by a computer is recorded,
A recognition step for recognizing a subdivision period obtained by subdividing each cycle of an input signal having periodicity;
Based on the subdivision period recognized by the recognition step, the characteristics of the input signal for m (where m is an integer of 1 or more) continuous subdivision periods are represented by the m continuous subdivision periods. The display size of the input signal characteristics for a minute and the display size along the direction corresponding to the time axis is displayed in a display mode in which the display size is fixed regardless of the length of m consecutive subdivision periods A generation process for generating display data of
A recording medium in which a computer program for causing the computer to execute an output step of outputting the display data to a display device is recorded.

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