JPS6097277A - Spectrum display apparatus - Google Patents

Abstract

PURPOSE:To dispense with memory having to store a max. level and to make it possible to shorten a time until display, by calculating diference level data when a real time level is smaller than the previous level. CONSTITUTION:The input audio signal arriving a terminal 1 is supplied to a multiplexer 3 through band zone filters 2a, 2b and supplied to an AD converter 6 while selected in a time series manner. When AD converting operation is performed predetermined times, FFT operation and power spectrum operation are performed in an operation and pitch-of-sound analytical part 9 and a pitch-of- sound level is judged. The output of each frequency band zone is compared with the previous level by a level comparing part 10 and, when smaller than the previous level, the level difference and pattern data corresponding to a this time level are taken out and a real time level pattern based on real time level data and a max. value level pattern based on the difference level data are simultaneously displayed by CRT16.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a spectrum display device, and more particularly to a spectrum display device that displays the level of an input audio signal at a predetermined position on a display screen for each different frequency band.

Prior Art The present applicant has previously proposed an apparatus that converts an input audio signal into a digital signal, performs frequency analysis to determine pitch, and displays the level of each frequency on a CRT in real time. This device performs FFT processing on audio signal data that has been converted into a digital signal, then calculates the result into a power spectrum to obtain a spectral value, judges the pitch, and uses this judgment result as a video display processor ( V.D.
P) to the video ram (V-RAM) and preset different frequencies (e.g. 50H2,
751-1z, 100H1,..., 12kf
-1z.

16 kHz2, 20kHz'z) Shun k1. The real-time level is displayed in the form of a bar graph and the maximum level is displayed in the form of points on the cRT display screen.

Problems to be Solved by the Invention However, the above device requires a memory to store the data necessary to display the maximum level, the amount of programs increases, and furthermore, it takes time to store the data. , so there were problems such as a certain amount of time required for display.

Means for Solving the Problems The present invention provides means for comparing the currently determined level with the previously determined level at predetermined intervals, and the currently determined level value as real-time level data. If the level is smaller than the previously determined level, a means for determining the difference between the real time level and the previously determined level as difference level data, and a bar displaying a real time level pattern on the display screen based on the real time level data. This system solves the above problems by having a configuration that displays the maximum level pattern simultaneously with the real-time level on the display screen based on the difference level data while displaying it in a graph. An example will be explained.

Embodiment FIG. 1 shows a block system diagram of an embodiment of the spectrum display device according to the present invention. In the same figure, the input audio signal coming into terminal 1 has a frequency of 50 Hz to 1.5 kl-1.
z bandpass filter 2a, 2kl-1z ~ 20kl-I
After unnecessary frequency components are removed by the Z bandpass filter 2b, the signals are supplied to the multiplexer 3. Initial setting is performed in the control unit 4 (step 30 in FIG. 2), and the bandpass filter 2a.

The signal from which 2b is extracted is selected and extracted in time series based on the switching signal from the switching signal generator 5, and is supplied to the AD converter 6. A conversion is performed (step 31) and the digital signal is stored in RAM8.

When the ΔD conversion operation has been performed a predetermined number of times, an FFT calculation is performed in the calculation and pitch analysis section 9 (step 32).
The calculation result is stored in the RAM 8, and then a power spectrum calculation is performed (step 33). Based on this calculation, the pitch level is determined (step 34).
It is stored in the RAM 8 for each frequency of ~20kHz.

Next, 50 Hz of each frequency band to be displayed is set (step 35), and compared with the previous level in the level comparing section 10 (step 36).

Here, if the level is higher than the previous level, a pattern data command signal corresponding to the larger level is extracted each time from the pattern data command section 11 and supplied to the pattern data determining section 12, and the pattern data corresponding to the above level is It is taken out (step 37). On the other hand, if it is smaller than the previous level, a pattern data command signal corresponding to the level difference between the previous level and the current level (substantially the difference between the real-time level and the maximum level) is extracted from the pattern data command unit 11. The pattern data is supplied to the pattern data determining section 12, and pattern data corresponding to this level difference and pattern data corresponding to the current level are extracted (step 38).

Next, it is determined whether the above operation has been performed up to 20 kHz of the frequency band to be displayed (step 39), and if it has not been performed for all frequencies yet, the next frequency of 75 Hz is set (step 40). , the same operation as above is repeated for each frequency band.

By the way, the present invention provides a mode in which the real-time level and the maximum level are displayed simultaneously on the same display screen (simultaneous display mode).
and a mode in which only the real-time level is displayed (single display mode) can be selected using the mode setting key 13. In the pattern data command section 11, a key scan is performed (step 41), and it is determined whether or not the simultaneous display mode is selected (step 42).If the mode is the single display mode, the maximum value level created in step 38, the actual While the time level difference data is replaced with transparent pattern data (described later) (step 43), in the simultaneous display mode, the level difference data is replaced with, for example, white pattern data (
(described later) (step 471), and these replaced pattern data are sent to the TV-TV via the VDP 14.
It is supplied to the RAM 15 and written into a predetermined table.

As shown in FIG. 3, the memory map of the V-RAM 15 includes a sprite generator table SGT and a pattern generator table PGT, which store a plurality of types of patterns necessary for spectrum display, and a CR shown in FIG. 4.
Tl6 is a pattern name table PNT1 having a capacity corresponding to each section of the display surface (32 columns x 24 rows), a sprite attribute table SAT that stores information on the vertical position and horizontal position of the display surface, and a color that stores color information. It is composed of tables CT and unused tables.

Here, one of the sections shown in Fig. 4 has, for example, a blue pattern b in the center and a transparent pattern (in the case of single display mode) or a white pattern (in the case of simultaneous display mode) on both sides, as shown in Fig. 6. The width of the blue pattern b corresponds to bar graph patterns P+ and P2 that display the real-time level.

The width ((Δ) in FIG. 5), which is two widths of the transparent pattern or the white pattern S, corresponds to the width between each of the bar graph patterns. Furthermore, the height of one section is a number.
It has the size of

In the VDP 14, a display 1 is displayed on the display screen of the CRT 16 in accordance with the data written in the pattern name table PNT and the sprite attribute table SAT in the v-RAM 15, and the pattern movement mode is specified.
Then, a composite video signal is created and supplied to the CRTl 6, where a bar graph pattern is displayed for each frequency at a predetermined position on the display surface thereof (steps 45 and 46).

For example, in the single display mode, FIGS.
), the previous level was 21. When the current level is 22, the maximum level, real-time level level difference pattern d, and both side patterns S in the same figure (A) are replaced with transparent patterns as shown in the same figure (B), while the current level is the previous level. If it is larger than the current level, the pattern S on both sides is replaced with a transparent pattern, and only the blue pattern b is made to have a size corresponding to the current level. In addition, in the simultaneous display mode, while the level difference pattern d and both side patterns S in the same figure (A>) are both replaced with the white pattern W as shown in the same figure (C), if the current level is higher than the previous level, The both-side patterns S are replaced with white patterns, and the blue pattern b is made to have a size corresponding to the current level.

Here, the background color of the display surface of the CRT 16 is preset to black, for example, and in the case of the single display mode, as shown in FIG. 5 (△), real-time level patterns P+, P2, . . . ... is displayed in the form of a blue bar graph, and even if there is a level difference pattern or a pattern on both sides, this part will be displayed in black on the background. In the case of simultaneous display mode, real-time level patterns P+ and P2 are displayed as shown in FIG. 5(B'').

... are displayed in the form of a blue bar graph, and the level difference pattern and both-side patterns are displayed in white with a black background around the patterns P+, P2, ....

In other words, in the simultaneous display mode, the real-time level is a bar graph pattern P+, P2 with white on both sides and blue in the center.
,... is displayed at the beginning of J:, and the maximum level is a pattern Q+, Q2 in which the level pattern is shortened and replaced with white when the real-time level decreases.
, ... is displayed by the beginning of the . In this way, the maximum level data uses the pattern data when the real-time level decreases, and both the real-time level data and the maximum level data can be written in the pattern name table of the V-RAM 15 with the same pattern name. It takes less time, can be displayed faster, and does not require special memory to store the maximum value level.

In addition, the 9 frequencies on the level scale, the letters, etc. are in the ROM.
17 is displayed in advance on a black background.

When the maximum level and real-time level are displayed in the simultaneous display mode, the entire display surface of the CRT 16 is cleared and then the level scale 2 frequency.

Other characters are displayed (step 47) in preparation for the next set mode display.

Modified Example Note that the pattern for displaying the maximum level is not limited to a white pattern as in the above embodiment, but as shown in FIG. A configuration in which r is regularly arranged may also be used. This is pattern P+ because the dot pattern arranged in the level direction can be used as it is as a level scale.

P2. It is easier to compare the sizes of..., and it is easier to read the level of the white pattern W only compared to.

Effects As described above, the spectrum display device according to the present invention includes a means for comparing the currently determined level with the previously determined level at predetermined intervals, and uses the currently determined level value as real-time level data. If the real-time level is smaller than the previously determined level, a means for determining the difference between the real-time level and the previously determined level as difference level data, and a display screen that displays a real-time level pattern based on the real-time level data. 1) means to display the maximum level pattern simultaneously with the real-time level on the display screen based on the difference level data, so that the maximum level data is displayed when the real-time level decreases. Using the pattern data of
Both real-time level data and maximum level data can be written to the pattern name table in the memory with the same pattern name, so writing time is short and display can be made faster, and special memory is not required to store the maximum level. For this reason, the program is simple, and we have selected a simultaneous display mode in which the real-time level and the maximum level are displayed on the display screen at the same time, and an independent display mode in which only the real-time level is displayed on the display screen. When the simultaneous display mode is selected, the real-time level pattern is displayed in the form of a bar graph on the display screen based on the real-time level data, while the real-time level pattern is displayed simultaneously on the display screen based on the difference level data. When the value level pattern is displayed and the single display mode is selected, the real-time level pattern is displayed on the display screen in the form of a bar graph based on the real-time level data, while the same as the background is displayed on the display screen based on the difference level data. Since colors or patterns are displayed, the image display mode can be arbitrarily selected as required, and has features such as ease of use.

[Brief explanation of drawings]

FIG. 1 is a block system diagram of one embodiment of the device of the present invention, and FIG.
3 is a flowchart for explaining the operation of the apparatus of the present invention, FIG. 3 is a memory map of the V-RAM, FIG. 4 is an explanatory diagram of sections of a CRT display screen, and FIG. 5(A). (B) is a diagram of the CRT display screen in single display mode and simultaneous display mode, respectively. Figure 6 is a diagram of one section of the CRT display surface. Figures 7 (A) to (C) are the real time level and maximum value level. FIG. 8 is a diagram illustrating the main part of a CRT display screen according to another embodiment of the apparatus of the present invention. 1... Audio signal input terminal, 4... Control device,
6...△D converter, 7... Conversion command and digital signal output section, 8... RAM, 9... Calculation and pitch analysis section, 10... Level comparison section, 11... Pattern data command section, 12... Pattern data determination section, 13...
・Mode setting key, 14...Video display・
Processor, 15...V-RAM, 16...CRT
XP+. P2...Real time level pattern, Q+,,Q2...
Maximum level pattern, b...blue pattern, S...
・Both sides pattern, d...level difference pattern, W...
white pattern.・

Claims (4)

[Claims] (1) Convert the input audio signal to a digital signal,
Based on the digital signal, the pitch and level are determined by frequency analysis and level analysis at a predetermined period, and the level of the audio signal is displayed on the display screen for each frequency band according to the determined pitch and level. A spectral display device that displays a spectrum, comprising means for comparing a currently determined level with a previously determined level at each predetermined period, and using the currently determined level value as real-time level data;
If the real time level is smaller than the previously determined level, means for determining the value of the difference between the real time 111 novel and the previously determined level as difference level data; It is characterized by comprising means for displaying the real-time level pattern in the form of a bar graph on the display surface, and displaying a maximum level pattern simultaneously with the real-time level on the display surface based on the difference level data. spectrum display device. (2) The maximum level is displayed in a color different from the color of the display pattern of the real-time level and the background color of the display surface, or in a color different from the display pattern of the real-time level and the back pattern of the display surface. A spectral display device according to claim 1, characterized in that the spectral display device has different patterns. (3) Convert the input audio signal to a digital signal,
Based on the digital signal, the pitch and level are determined by frequency analysis and level analysis at a predetermined period, and the level of the audio signal is displayed on the display screen for each frequency according to the determined pitch and level. In a spectral display device that displays a spectrum (spectrum), the currently determined level is compared with the previously determined level at each predetermined period, and the currently determined level value is used as real-time level data. If the real time level is smaller than the previously determined level, means for determining the difference between the real time level and the previously determined level as difference level data, and simultaneously determining the real time level and the maximum level. means for selecting a simultaneous display mode for displaying on the display screen and a single display mode for displaying only the real time level on the display screen, and when selecting the simultaneous display mode, the real time level is displayed based on the real time level data While the level pattern is displayed in the form of a bar graph on the display screen, a maximum level pattern is displayed simultaneously with the real time level on the display screen based on the difference level data, and when the individual display mode is selected, the maximum level pattern is displayed on the display screen based on the difference level data. Displaying the real-time level pattern in the form of a bar graph on the display surface based on the time level data;
A spectral display device d0 comprising means for displaying the same color or pattern as the background on the display surface based on the difference level data. (4) The maximum level is displayed in a color different from the display pattern of the real-time level and the background color of the display surface, or in a color different from the display pattern of the real-time level and the back pattern of the display surface. 4. A spectral display device according to claim 3, characterized in that the spectral display device has different patterns.