JP4412246B2 - Tuner and its program - Google Patents

Description

  The present invention relates to a tuner, and more particularly to a tuner that displays a display object indicating a deviation between a frequency of an acoustic waveform input from the outside and a tuning target frequency, and a program thereof.

  Conventionally known tuning instruments used for tuning natural instruments such as pianos, the pitch of the musical tone (instrument performance sound) emitted from the instrument is the tuning target frequency (frequency to be tuned). Some of them have a function of displaying whether or not the pitch is met. The operator can tune the instrument while watching the display on the tuner. In this type of tuner, the following methods are known as methods for measuring the pitch (pitch) of musical sounds emitted from musical instruments. That is, a binary reference waveform is created by shaping the input waveform into a rectangular pulse wave that is inverted to “1” or “0” for each zero cross point, and the created reference waveform is delayed by a predetermined time. There is known a method of measuring a pitch of an input waveform by creating a delayed waveform, obtaining a correlation between a reference waveform and a delay waveform, and setting a delay amount having a high correlation as a period of the input waveform. By measuring the pitch in this way, the shift amount between the tuning target frequency and the measured pitch (frequency of the input waveform) could be presented to the operator by display on a meter or the like (for example, the following patent document) 1).

Various types of methods for displaying the deviation between the tuning target frequency and the frequency of the input waveform are known. For example, it has a display device in which a plurality of LEDs are arranged in a row in association with a predetermined time range (phase range), and a rectangular pulse shaped wave of an input waveform over the time range (phase range) and a comparison reference rectangle By controlling the lighting / non-lighting of each LED based on the comparison with the pulse wave, the phase relationship between the two, that is, the frequency or cycle relationship, is displayed in an analog manner according to the lighting / non-lighting pattern. Some are updated every display update cycle (see Patent Document 2 below). According to this, when the frequency of the tuning target frequency (rectangular pulse wave for comparison reference) and the frequency of the input waveform are deviated, the position of the LED in the lighting state is sequentially changed, so that the appearance of the LED is apparently changed. The lighting is controlled so that the lighting pattern flows on the display. On the other hand, when the frequency to be tuned matches the frequency of the input waveform, the lighting pattern appears to stop at a certain position. To do.
Japanese Patent Laid-Open No. 9-257558 JP-A-5-313657

Since the pitch deviation display of the type disclosed in Patent Document 2 can determine whether or not the frequency to be tuned is different from the frequency of the input waveform (piano sound) by the movement of the LED lighting pattern on the display, it can be determined. However, it was advantageous in that it was good.
However, the tuner disclosed in Patent Document 2 has the following disadvantages. FIG. 9 is a diagram showing an outline of the principle of display control in the tuner disclosed in Patent Document 2. FIG. 9A shows the tuning target frequency (comparison reference rectangular pulse wave) and the frequency of the input waveform. In the case of coincidence, (b) shows a case where the tuning target frequency and the frequency of the input waveform are shifted. In (a), (1) is a waveform diagram of an input waveform 100a, and (2) is an LED based on a comparison between a rectangular pulse shaped wave of the input waveform 100a of (1) and a rectangular pulse wave for comparison reference. The lighting / non-lighting pattern 101a is shown. In the figure, for example, the colored portion of the lighting / non-lighting pattern 101a is regarded as LED lighting, and the white portion is regarded as LED non-lighting. When the tuning target frequency and the frequency of the input waveform match as shown in (a), it can be seen from the figure that the lighting pattern updated at each display update cycle has a certain periodicity. In this case, the lighting pattern of the LED seems to be stopped. On the other hand, in (b), the input waveform 100b in (3) is shifted from the tuning target frequency. This is apparent from the fact that the periodicity of the lighting / non-lighting pattern 101b shown in (4) deviates from the time range (phase range) of the display. However, in the case of (b), since the display update cycle of the display device has a relationship between the cycle of the frequency of the input waveform, the cycle of the tuning target frequency, and a common multiple, the lighting pattern updated at each display update cycle is constant. Will have a periodicity of. Therefore, even if the frequency of the input waveform 100b is different from the tuning target frequency, the lighting pattern appears to stop at a certain position. As described above, in the tuner disclosed in Patent Document 2, when the display update cycle has a relationship between the cycle of the frequency of the input waveform, the cycle of the tuning target frequency, and a common multiple, the frequency other than the tuning target frequency. Even if the input waveform is, the lighting pattern appears to stop at a fixed position, which makes it impossible to determine whether the tuning target frequency matches the frequency of the input waveform (piano sound). .

  The present invention has been made in view of the above points, and an object of the present invention is to provide a tuning device that can clearly indicate the deviation (match / mismatch) between the frequency of an external input waveform and the tuning target frequency. To do.

  The present invention is a tuning device having a display that updates and displays a display object indicating a deviation between a frequency of an acoustic waveform input from the outside and a predetermined tuning target frequency at a predetermined display update period, A waveform section over a predetermined time range for each period corresponding to the tuning target frequency having a resolution finer than the display update period. Extracting means for generating, display information creating means for creating display information that clearly indicates the periodicity of the waveform in the section for each of the extracted waveform sections, and the display section created in one cycle of the display update period. The tuning device is characterized by comprising display control means for superimposing the display information for each waveform section and causing the display to display in a display form corresponding to the superposed multi-value information.

  In the tuning information device according to the present invention, in the display information generating means, for each of the extracted waveform sections, the waveform in the section is binarized into binary information whose value is inverted at each zero cross point. And a display controller for superimposing the binarized information for each waveform section created within one display update period into multi-valued information. It is characterized by being displayed.

  Furthermore, the present invention causes a computer to execute a tuning process including a function of updating and displaying a display object indicating a deviation between a frequency of an acoustic waveform input from the outside and a predetermined tuning target frequency at a predetermined display update period. A software program, a procedure for inputting an external acoustic waveform, and a predetermined time range for each period according to the tuning target frequency having a resolution finer than the display update period from the input acoustic waveform Each of the extracted waveform sections, a procedure for creating display information that clearly indicates the periodicity of the waveform in each of the extracted waveform sections, and creation within one cycle of the display update period The display information for each of the waveform sections is superimposed and displayed on the display in a display form corresponding to the superimposed multi-value information. It may be configured as a program to be.

  According to the tuning device of the present invention, when an acoustic waveform is input from the outside, the extraction unit extracts, from the input acoustic waveform, every cycle corresponding to the tuning target frequency having a resolution smaller than the display update cycle. In addition, waveform sections over a predetermined time range are extracted. Display information creation means creates display information for each of the extracted waveform sections that clearly indicates the periodicity of the waveform within the section. Then, the display control means superimposes the display information for each waveform section created within one display update period, and displays the display in a display form according to the superimposed multi-value information. Display. When the frequency to be tuned and the frequency of the acoustic waveform match, the phase relationship of the waveforms in each waveform section extracted by the extraction means, that is, the periodicity, matches, so the multi-value information that overlaps them The corresponding display form is an image having the same periodicity as the waveform of each extracted waveform section, and is displayed as if it is stopped at a fixed position. On the other hand, when the frequency to be tuned and the frequency of the acoustic waveform are deviated, the waveforms of the respective waveform sections extracted by the extracting means are shifted in phase relationship, that is, periodicity, and thus these are overlapped. The display form according to the multi-value information is a multi-value grayscale image having multi-level (at least three levels) gray levels according to the phase relationship (phase shift) of the extracted waveform sections. Become. For this reason, even if the frequency of the acoustic waveform deviates from the tuning target frequency, there are many display forms of the display object even when the display object appears to stop at a certain position (see FIG. 9). By having gradations of stages (at least three stages or more), it is possible to clearly indicate that the frequency of the acoustic waveform is different from the tuning target frequency. Therefore, it is possible to clearly indicate whether or not the frequency of the acoustic waveform and the tuning target frequency match, and it is possible to cope with cases where the frequency matching / mismatching has been insufficient in the past. Has an effect.

An embodiment of the present invention will be described below with reference to the accompanying drawings. The tuning device according to this embodiment is typically used for tuning an acoustic piano.
FIG. 1 is a conceptual diagram for explaining the outline when the tuner according to one embodiment of the present invention is used. In FIG. 1, reference numeral 1 denotes a tuning device according to this embodiment, and reference numeral 2 denotes a keyboard instrument (upright piano) having an acoustic sound generation mechanism as an example of an instrument to be tuned. The tuner 1 is composed of, for example, a PDA (Personal Digital Assistant), and can execute a software program for realizing a tuning function according to this embodiment. The tuner 1 includes a display 3 (for example, a liquid crystal screen) 3 capable of displaying information and inputting an operation from the screen, as is common with known PDAs. The tuner 1 is connected to a microphone 4 for acquiring a piano performance sound produced on the piano 2. The sound picked up by the microphone 4 is supplied as an input waveform to the tuner 1. As will be described in detail later, according to the tuning function according to this embodiment, the tuner 1 is configured so that the phase relationship between the frequency of the input waveform supplied via the microphone 4 and the frequency for comparison (tuning target frequency), that is, the frequency. Alternatively, an image (display pattern) indicating the periodic relationship can be displayed on the display 3. In FIG. 1, for convenience of illustration and explanation, the microphone 4 is depicted as being externally connected to the tuner 1, but the microphone 4 may be configured to be incorporated in the tuner 1. .

FIG. 2 is a block diagram showing an outline of the electrical hardware configuration of the tuner 1. The tuner 1 includes a microcomputer including a CPU 10, a ROM 11, and a RAM 12, an interface 13 for capturing an input waveform supplied from the microphone 4, a display control unit 14, and an operation detection unit 15. 16 is connected. The interface 13 includes an amplifier and an AD converter. The analog audio waveform signal input via the microphone 4 is appropriately amplified and converted into a digital waveform signal and supplied to the signal processing system. The display control unit 14 controls display on the display 3 based on an instruction from the CPU 10. The display on the display 3 in the PDA is updated by software at a period of about 15 to 20 Hz, and this period is slower than the frequency of the lowest piano sound that can be input to the tuner 1. In addition, an instruction corresponding to an operation input on the display 3 or an input of another operation element is given to the CPU 1 via the operation detection unit 15.
The CPU 10 controls the overall operation of the tuner 1 and executes a software program for realizing the tuning function according to this embodiment. A software program for realizing the tuning function may be stored in a memory such as the ROM 11. The RAM 12 is used as a work area for storing various parameters and various data or a memory area for storing waveform data acquired via the microphone 4 when the CPU 10 executes signal processing.

  FIGS. 3A and 3B are diagrams showing an example of a display screen read out by the display device 3. The display screen 30 is provided with a waveform display unit 31 for displaying an image “display pattern 32” indicating a deviation between the tuning target frequency and the input waveform frequency (the phase relationship between the two). FIG. 3A shows a display pattern 32 when the tuning target frequency matches the frequency of the input waveform (piano sound), and FIG. 3B shows the case where the tuning target frequency and the input waveform frequency are shifted. The display pattern 32 is shown. The principle of display control and display operation of the display pattern 32 will be described later.

Further, the display screen 30 includes an operation input unit 33 including a group of button images for inputting information such as numerical values and pitch names (A to F). The user can input an operation by applying an operation tool such as a pen to the button image displayed on the screen. The user designates a pitch to be tuned and sets various parameters from the operation input unit 33. A set value display section 34 of the display screen 30 displays set values of various parameters such as pitches to be tuned.
As shown in the figure, the parameters displayed on the set value display section 34 include a note name (note), an octave (oct.), A key number (keyNo.), A cent value (cent), and a tuning target frequency (freq). ) The user can specify the pitch name (note) and octave (oct.) Values by inputting the pitch name / numerical value using the button image of the operation input unit 33 or the like. As is well known, the key numbers (key No.) are assigned to each of the 88 keys provided on the piano keyboard by sequentially assigning numbers 1 to 88 in order from the lowest key to the highest key. If the pitch is specified by the pitch name and the octave, the key number corresponding to the pitch is uniquely determined. That is, the user can designate the tuning target pitch to be tuned by designating the pitch name and the octave. The tuning target frequency basically corresponds to a frequency corresponding to the designated tuning target pitch. The regular frequency corresponding to the pitch is a predetermined value set in advance for each pitch, and may be set by referring to a table, for example. Hereinafter, in this embodiment, a parameter indicating the value of the tuning target frequency is referred to as “Hz value”. The cent value is a parameter for the user to arbitrarily correct the Hz value. Accordingly, the tuning value frequency (freq) column of the set value display unit 34 displays the Hz value obtained by correcting the frequency of the specified tuning target pitch with a cent value. For example, as shown in the figure, if the specified pitch is 5th octave A (key No. = 49) and the cent value is 0, the frequency to be adjusted is the frequency corresponding to the 5th octave A (this In the example, 440 Hz). As is well known, the cent value is a value representing a pitch difference in a logarithmic expression, and 100 cents corresponds to a 12-tone semitone.

  4 and 5 are conceptual diagrams for explaining the principle of display control of the display pattern 32. FIG. 4 (a) and 4 (b), waveforms indicated by reference numerals 40a and 40b are input waveforms (piano sound) input to the tuner 1. In the display control of the display pattern 32 according to this embodiment, a waveform section spans a time range (phase range) based on a window width parameter “W value” to be described later for each period of the tuning target frequency Hz from the input waveform. The process of extracting the waveform is performed, and display information that clearly indicates the periodicity of the waveform in the section is created for each extracted waveform section. The display information is binarized information (see FIG. 7 described later) obtained by inverting the waveform to “1” or “0” for each zero cross point, and the waveform periodicity for each section is 2 This is data that can be imaged at a step density. Then, the display information for each waveform section created within one display update period of the display screen 30 (display 3) is overlaid, and a display form corresponding to the superposed multi-value information is superimposed. The display pattern 32 is displayed on the display 3. The above is the outline of the principle of display pattern display control according to this embodiment.

In FIG. 4A, (1) shows a waveform diagram when an input waveform 40a having a frequency matching the tuning target frequency Hz is inputted, and (2) shows tuning from the input waveform 40a of (1). Waveforms 41a to 41e for each waveform section extracted for each cycle of the target frequency Hz. In the figure, the waveforms 41a to 41e for each waveform section are “1” or “0” for each zero-cross point of each waveform. The periodicity of each waveform is imaged with two levels of density (periodic pattern) by the binary display information inverted to "". Since the frequency of the input waveform 40a matches the tuning target frequency Hz, the extraction of the waveforms 41a to 41e in each waveform section is performed at a timing synchronized with the period of the input waveform 40a. Accordingly, waveforms having the same phase relationship, that is, having the same periodic characteristics are extracted as the waveforms 41a to 41e in each waveform section. When the images of the periodic patterns of the waveforms 41a to 41e in these waveform sections are superimposed, a display pattern 32a as shown in FIG. 5A can be obtained. Since the periodicity of each of the waveforms 41a to 41e is the same, the display pattern 32a obtained by superimposing these waveforms is a two-level gray image having the same periodicity as each of the waveforms 41a to 41e. It can be seen from.
On the other hand, in FIG. 4B, (3) shows a waveform diagram when an input waveform 40b having a frequency different from the tuning target frequency Hz is input (when the Hz value and the frequency of the input waveform are shifted). 4) shows a periodic pattern in which waveforms 41f to 41j for each waveform section extracted from the input waveform 40b of (3) for each period of the tuning target frequency Hz are imaged at two levels of density. In this case, since the input waveform 40b and the tuning target frequency Hz are deviated, periodic patterns having different phases are extracted as the waveforms 41f to 41j in the respective waveform sections. When the images of the periodic patterns of the waveforms 41f to 41j in these waveform sections are superimposed, a display pattern 32b as shown in FIG. 5B can be obtained. Since the phase relationship between the waveforms 41f to 41j is deviated, the display pattern 32b obtained by superimposing these waveforms has multiple levels (at least three or more levels) of light and shade according to the phase relationship deviation between the waveforms 41f to 41j. It becomes a multi-value grayscale image.

  Display patterns 32a and 32b shown in FIGS. 5A and 5B are obtained by superimposing waveforms 41a to 41e and 41f to 41j for each waveform section extracted within one display update period ( (Refer FIG. 4 (a), (b)). That is, in this embodiment, as many waveforms as possible within the display update cycle (five in the example in the figure) are extracted for each waveform section, and each extracted for each display update cycle is extracted. The display mode of the display pattern 32 is updated by superimposing the waveform display information for each waveform section. As shown in FIG. 5A, when the frequency of the input waveform 40a matches the tuning target frequency Hz, the display pattern 32a that is updated at each display update cycle has two stages with the same periodicity. Since it is a grayscale image, it appears to be stopped in the display mode of the display pattern 32a. On the other hand, as shown in FIG. 5B, when the frequency of the input waveform 40b is different from the tuning target frequency Hz, the periodicity of the display pattern 32b updated at each display update period is not constant. Therefore, the display pattern 32b appears to flow on the waveform display unit 31 (see FIG. 3), and the display mode does not stop in a fixed state. Even if the display pattern 32b appears to be stopped when the display update period of the display device has a relationship between the frequency period of the input waveform 40b, the period of the tuning target frequency Hz, and a common multiple, In the pattern 32b, a shift between the frequency of the input waveform 40b and the tuning target frequency Hz can be clearly indicated by a multi-value gray image having multi-level (at least three or more levels) gray levels. Details of the display control operation of the display pattern 32 will be described later.

  A time range (phase range) for extracting each waveform section from the input waveform, that is, a width (window width) for applying a window to the input waveform is set based on the window width parameter “W value”. The W value is a parameter that defines a time range (phase range) for extracting a waveform for each waveform section depending on how many cycles of the waveform of the tuning target frequency Hz are extracted. For example, in the example shown in FIGS. 4 to 5, the W value is set to extract 2.5 waveforms of the tuning target frequency Hz as the time range of the waveform section. If the period of the Hz value and the period of the input waveform 40a coincide with each other, a waveform of exactly 2.5 periods is extracted as the waveforms 41a to 41e, and a period of 2.5 periods is obtained as a display pattern 32a obtained by superimposing these waveforms. A pattern image is displayed (see FIGS. 4 to 5A). Further, when the period of the Hz value and the period of the input waveform 40b are deviated from each other, if they do not coincide with each other, the extracted waveforms 41f to 41j are represented by 2 as shown in FIG. The waveform does not become 5 cycles. By changing the setting of the W value, the display size of the display pattern 32 (see FIG. 3) in the waveform display unit 31 can be changed. If the time range for extracting the waveform for each waveform section is reduced, the display size of the display pattern 32 in the waveform display unit 31 is relatively increased. By enlarging the display size of the display pattern 32, the user can visually recognize even a slight deviation between the period of the Hz value and the period of the input waveform 40a, and there is an advantage that more precise tuning can be performed.

Next, an operation procedure for executing the tuning operation in the tuning device 1 according to this embodiment will be described with reference to the flowcharts of FIGS. 6 and 7.
In response to turning on the power of the tuner 1, the tuner 1 executes the processing shown in the flowchart of FIG. 6. In step S1 of FIG. 6, various parameters are initially set. The parameters that are initially set here are a reference pitch, a tuning target frequency (Hz value), a cent value, a W value, and the like. Assume that the initial setting values of the respective parameters are set to, for example, reference pitch = 440 Hz, tuning target frequency Hz = 440 Hz, cent value = 0 cent, and W value = 2.5 periods of the Hz value. In step S <b> 2, the operator inputs a reference pitch (standard pitch) for setting a scale in the tuner 1. That is, the frequency of the A sound (A of key number 49) at the center of the piano serving as the reference pitch can be arbitrarily selected from several candidates such as 440 Hz, 442 Hz, or 439 Hz. Subsequently, in the tuner 1, the display of the display pattern 32 is started on the waveform display unit 31 on the display screen 30 (see FIG. 3), and the display control operation (task) shown in FIG. Step S3 and Step S4). In FIG. 6, “display start” in step S3 and “task start” in step S4 are depicted as separate steps for convenience of illustration and description. Is responding to the start of
In step S5, selection of a tuning curve is accepted. The tuning curve is a data table that defines the frequency of the pitch corresponding to each of the 88 keys of the piano. As a tuning curve, a piano type (grand piano / upright piano) and a plurality of types of data tables corresponding to the size and the like are stored in appropriate memories such as ROM2 to RAM3. It may be possible to select a tuning curve according to. The frequency of each pitch described in the tuning curve is set so that the pitch on the high pitch side is higher than the theoretical value of the frequency based on the average rate in consideration of the characteristics of the piano. Based on the frequency set as the reference pitch in step S2, the theoretical value of the frequency of each pitch based on the average rate can be calculated. However, in actual piano tuning, it may be inappropriate to apply the theoretical value as it is as the frequency of each pitch. In that case, by using the tuning curve, it is possible to obtain a frequency for each pitch suitable for the characteristics of the piano and the type or size of the piano to be used.

  Steps S <b> 1 to S <b> 5 are processes corresponding to initial settings when the tuner 1 is used. That is, the execution order of these steps S1 to S5 is not limited to the order shown. The user sets various parameters in steps S6 to S11 described below.

When the pitch to be tuned is specified by the user's operation input (see FIG. 3 etc.) (yes in step S6), the tuning curve selected in step S5 or the theory based on the equal temperament is selected in step S7. Based on the value, the frequency of the designated pitch is obtained, and this value is set to the parameter “Hz value” of the tuning target frequency. When a cent value is input by a user's operation input (yes in step S8), in step S9, the tuning target frequency Hz is corrected according to the input cent value. In step S10, selection of the display size of the display pattern by changing the W value is accepted. According to this embodiment, the user can select either the normal size or the enlarged size as the display size of the display pattern. That is, when the W value is changed (Yes in Step S10), in Step S11, the W value is set according to the change. When the W value is changed, the time range for extracting the waveform section from the input waveform is changed, so that the display size of the display pattern can be arbitrarily changed. As a method of changing the display size, it is possible to use it when, for example, the tuning is performed roughly while viewing the normal size display, and then the display size is enlarged to see a subtle frequency shift.
Thereafter, while the tuner 1 is powered on, steps S6 to S11 are repeated, so that the Hz value change and display size change by the user can be accepted.

FIG. 7 is a flowchart showing the procedure of the display pattern display control operation that starts in steps S3 and S4 of FIG.
The process shown in FIG. 7 is a timer process that is activated at each activation timing corresponding to the display update cycle of the display 3 (display screen 30) of the tuner 1, and the waveform display unit 31 is activated at each activation opportunity of this process. The display pattern 32 (see FIG. 3) is updated. In this embodiment, as an example, the tuner 1 is configured by a PDA. As described above, the display on the display device 3 in the PDA is updated by software at a period of about 15 to 20 Hz. Therefore, the process is also started with a period of about 15 to 20 Hz.
In step S20, an input waveform (piano sound) input via the microphone 4 is sampled at a predetermined sampling period, and the piano sound is taken into the tuner 1. The sampling frequency is 44.1 kHz, for example. In step S21, the input waveform (digital waveform signal) sampled at each sampling timing is written in the memory area on the RAM 12. In step S22, it is determined whether or not waveform data sample data of a predetermined number of samples or more has been read into the memory area on the RAM 12. When the reading of the waveform signal sample data is less than the predetermined number of samples (no in step S22), the waveform signal is captured (steps S20 and S21) until the waveform signal sample data reaches the predetermined number of samples. repeat. On the other hand, when the sample data of the waveform signal read into the memory area on the RAM 12 reaches the predetermined number of samples (Yes in step S22), the process proceeds to the next step S23. The predetermined number of samples is about 1024 to 2048 samples.

  In step S23, the filter coefficient (passing bandwidth and center frequency) of the bandpass filter is set based on the parameter Hz value of the tuning target frequency set in step S7 or S9 of FIG. The waveform read into the memory area is subjected to band pass filter processing using the set filter coefficient. By this filtering process, harmonic components and the like included in the input waveform can be removed and the tuning frequency component can be extracted.

  In step S25, based on the W value set in step S11 of FIG. 5, the number of cycles for extracting the waveform for each waveform section (window width) is set. If the W value is set to 2.5 periods, the window width is a time range corresponding to 2.5 periods of the tuning target frequency Hz.

In step S26, the waveform of the waveform section having the window width set in step S25 is extracted (turned on the window) for each period of the tuning target frequency Hz value from the input waveform. Thereby, the waveform for every waveform section of the time range according to the W value is extracted for a plurality of sections according to the number of times the period of the Hz value arrives within one display update period.
In step S27, for each extracted waveform section, the waveform in the section is shaped into binary information that is inverted at each zero-cross point with values of “0” and “1”, so that the periodicity is obtained. Display information (“binarization information”) that is clearly indicated by binary shading is created. 8 (a) and 8 (b), a configuration example of the binarized information of the waveform for each extracted waveform section (binary information that is inverted with a value of “0” or “1” for each zero cross point). In addition, on the right side of each binarized information, each binarized information is shown as a periodic pattern consisting of two levels of shading. As shown in FIGS. 8A and 8B, the binarized information is composed of data in which each address is associated with a phase (time) in the waveform section. That is, in the example of the figure, the binarization information divides the time range of 2.5 cycles of the Hz value period into 25 stages of addresses, and the value “0” or “1” of each address This is data representing the periodicity of the waveform in the waveform section with two levels of density (“0” or “1”). FIG. 4A shows a case where the input waveform and the period of the Hz value coincide with each other, and FIG. 5B shows a case where the input waveform and the period of the Hz value are shifted. For convenience of illustration and explanation, each waveform section is shown. Similar to FIGS. 4 and 5, reference numerals 41 a to 41 e (FIG. 8A) and reference numerals 41 f to 41 j (FIG. 8B) are given to the respective waveforms.

In step S28, an arithmetic average of the binarized information for each waveform section created within one display update cycle is obtained to obtain multivalued information (multivalued) obtained by superimposing the binarized information. Information). In step S29, the display pattern 32 is displayed on the waveform display unit 31 in the display form based on the multi-value information created in step S28. The display pattern 32 is an image that shows a grayscale image based on multi-value information by luminance or hue difference (see the display screen 30 in FIGS. 3A and 3B).
As shown in FIG. 8A, when the frequency of the input waveform matches the tuning target frequency Hz, the multi-value information 42a that is an arithmetic average of the binarization information 41a to 41e is the waveform 41a. Binary data having the same periodicity as ˜41e (“0” or “5” in the figure). Therefore, the display pattern 32a displayed based on the multi-value information 42a is a two-level gray image. On the other hand, as shown in FIG. 8B, when the tuning target frequency Hz value and the frequency of the input waveform do not match, the multi-value quantization obtained as an arithmetic average of the binarization information 41f to 41j for each waveform section The information 42b is information having multi-stage values (three or more stages; “1”, “2”, “3” or “4” in the figure). Accordingly, the display pattern 32b displayed based on the multi-value information 42b is a gray image having multi-level (three or more levels) density changes.

  By executing the processes of steps S20 to S29 according to the display update cycle of the display screen 30, the display form of the display pattern 32 is updated for each display update cycle. Thus, when the tuning target frequency Hz and the frequency of the input waveform match (see FIG. 8A), the display pattern 32a having two levels of shades with the same periodicity is displayed for each display update cycle. Since it is repeatedly displayed, it appears that an image in a display form consisting of two levels of shade appears to stop at a certain position. On the other hand, when the tuning target frequency Hz and the frequency of the input waveform do not match (see FIG. 8B), the display pattern 32 is roughly displayed in the following two ways. That is, since the periodicity of the display pattern 32b updated at each display update cycle is not constant (the phase of the display pattern updated at each display update cycle is shifted), the display pattern 32b appears to be a waveform display. It seems that it is flowing on the part 31 (see FIG. 3), and its display mode does not stop in a constant state. Alternatively, when the display update cycle has a relationship between the frequency cycle of the input waveform and the cycle of the tuning target frequency Hz and a common multiple, the display pattern 32b is constant even if the frequency of the input waveform does not match the tuning target frequency Hz. Although it appears to be stopped at the position, according to this embodiment, the density of the grayscale image is displayed in multiple stages (three or more stages) as in the display pattern 32b, so that the frequency of the input waveform is displayed. It can be clearly shown that the tuning target frequency Hz is shifted. Therefore, the conventional inconvenience as described with reference to FIG. 9 can be solved.

  As described above, according to this embodiment, it appears that the display pattern 32 having two-level shading stops at a fixed position only when the tuning target frequency Hz value and the frequency of the input waveform match. When the tuning target frequency Hz value is different from the input waveform frequency, the display pattern 32 is an image having multiple levels (three or more levels), so the input waveform frequency and tuning target frequency Hz are shifted. This can be clearly recognized by the display form of the display pattern.

  In the above embodiment, in the process of applying a window to the input waveform, it has been described that the waveform of the waveform section over a predetermined time range is extracted for each period of the tuning target frequency Hz, but the period of extraction of the waveform section is The period of the Hz value does not need to be strictly limited, and the resolution may be extracted with an appropriately thinned period as long as the resolution is finer than the display update period of the display screen 30. Moreover, in the said Example, the number of the waveforms (41a-41e, 41f-41j) for every waveform area to superimpose in order to obtain a display pattern is decided according to a tuning object frequency (Hz value) and a display update period. However, this is not limited to this and is extracted and superimposed as many as possible within one display update cycle. However, the present invention is not limited to this. The number may be set to a predetermined number.

Further, in step S27 of FIG. 7 described above, the waveform for each of the plurality of waveform sections is shaped into binary information whose value is inverted at each zero cross, and display information that clearly indicates the periodicity of the waveform in the section is created. However, the display information created here is not limited to the example of binarizing the waveform for each section, but may be information that can display the periodicity (phase) of the waveform for each section as an image. For example, the information may be in any format such as multi-value information indicating the periodicity of the waveform for each section.
Further, in step S28 of FIG. 7 described above, multivalued information is created by calculating an arithmetic average of the binarized information for each of the plurality of extracted waveform sections, and in step S29, based on the multivalued information. Although the example which displays the display pattern 32 was demonstrated, the multi-value information for displaying the display pattern 32 is not restricted to the value of the arithmetic mean of binarization information, For example, binarization information is added and a total value It may be. In other words, the multilevel information may be any type of information as long as it can express multi-level shading obtained as a result of superposing a plurality of waveforms cut out from the input waveform.

Further, the display control shown in FIG. 7 is started in accordance with the display update cycle of the display 3, but this process may be a process that is started every cycle for updating the display of the display pattern 32. That is, it may be configured as a timer process having a routine for controlling the time interval of the display update cycle of the display pattern 32 in the process. In the above-described embodiment, the display pattern 32 is an image showing a grayscale image based on multi-value information by a difference in luminance or hue. However, the display pattern 32 is not limited to this. An appropriate multi-valued display mode such as expressing shades of steps may be applied.
As an example of changing the display pattern display control, in the case of a display pattern having multi-level shading (that is, when the frequency of the input waveform and the tuning target frequency Hz are shifted), the display color is changed. It may be. In this case, since it is possible to determine whether or not the tuning target frequency Hz value matches the frequency of the input waveform according to the display color of the display pattern, the display information for each waveform section is overlapped to be multi-valued. It is not necessary to display the displayed display pattern. That is, one of the display information extracted for each waveform section is used as a display pattern, and whether or not it has multi-level shading (whether the tuning target frequency Hz value and the frequency of the input waveform are shifted). The display color may be varied depending on

  In the above embodiment, the example in which the tuner according to the present invention is configured by a PDA (personal digital assistant) has been described. However, the present invention is not limited to this, and an apparatus capable of executing a software program that realizes the tuning function described above. As long as there is, it may be configured and implemented by a personal computer or other appropriate device. Moreover, you may comprise by the tuner etc. provided with the signal processing circuit which implement | achieves the tuning function mentioned above. Further, the display is not limited to the liquid crystal screen, and may be configured by a plurality of LEDs arranged in a row in association with a predetermined time range (phase range). Further, the present invention may be configured and implemented as a software program that realizes the tuning function described above in a computer.

The external view which shows the whole image at the time of using the tuner based on one Example of this invention. The block diagram which shows the electric hardware constitutions of the tuner based on the Example. It is a figure which shows an example of the display screen of the tuning device which concerns on the Example, Comprising: (a) is a state in which the frequency of a tuning object and the frequency of an input waveform correspond, (b) is the frequency of a tuning object frequency and an input waveform. Are inconsistent. It is a figure for demonstrating the outline | summary of the display control principle of the display pattern in the tuner which concerns on the Example, Comprising: (a) is a state in which the frequency of a tuning object frequency and the frequency of an input waveform correspond, (b) is a tuning. The target frequency does not match the input waveform frequency. FIG. 5 is a diagram showing that the input waveform shown in FIG. 4 and the extracted waveform sections extracted and overlaid are displayed temporarily. The flowchart which shows the outline | summary of the use procedure in the tuner based on the Example. The flowchart which shows the procedure of the display control in the tuner based on the Example. It is a conceptual diagram for demonstrating the binarization information created based on an input waveform in the tuner based on the Example, and multi-value information based on this binarization information, (a) is a tuning object frequency and The state in which the frequency of the input waveform matches, (b) is the state in which the frequency to be tuned and the frequency of the input waveform do not match. It is a figure for demonstrating the inconvenience in the conventional tuner, Comprising: (a) is a state in which the frequency of a tuning object and the frequency of an input waveform correspond, (b) is a frequency in which a tuning object frequency and the frequency of an input waveform do not correspond. Status.

Explanation of symbols

1 Tuner, 2 Piano, 3 Display, 4 Microphone, 10 CPU, 11 ROM, 12 RAM, 13 Interface, 14 Display control unit, 15 Operation detection unit, 30 Display screen, 31 Waveform display unit, 32 Display pattern

Claims (3)

A tuning device having a display for updating and displaying a display object indicating a deviation between a frequency of an acoustic waveform input from the outside and a predetermined tuning target frequency for each predetermined display update cycle,
An input means for inputting an external acoustic waveform;
Extraction means for extracting each waveform section over a predetermined time range from the input acoustic waveform for each period according to the tuning target frequency having a resolution finer than the display update period,
Display information creating means for creating display information that clearly indicates the periodicity of the waveform in the section for each extracted waveform section;
Display control means for superimposing the display information for each waveform section created within one period of the display update period, and causing the display to display in a display form according to the superimposed multi-value information; A tuning device characterized by comprising. The display information generating means further comprises means for binarizing the waveform in the extracted waveform section into binary information whose value is inverted at each zero cross point for each of the extracted waveform sections.
The display control means causes the display to display multivalued information by superimposing the binarized information for each waveform section created within one display update period. The tuning device according to claim 1, wherein: A software program for causing a computer to execute a tuning process including a function of updating and displaying a display object indicating a deviation between a frequency of an acoustic waveform input from the outside and a predetermined tuning target frequency for each predetermined display update cycle,
The procedure to input an external acoustic waveform,
From the input acoustic waveform, for each period according to the tuning target frequency having a resolution finer than the display update period, a procedure for extracting each waveform section over a predetermined time range;
For each of the extracted waveform sections, a procedure for creating display information that clearly indicates the periodicity of the waveform in the section;
A procedure for superimposing the display information for each waveform section created within one display update period and causing the display to display in a display form according to the superimposed multi-value information. A program characterized by

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