JPS582898A - Waveform compressor - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION This li@ is a waveform compression device that performs efficient compression using repetition of a human signal waveform in 41. Regarding.

Conventionally, there are eight known compression techniques that perform waveform compression using repetition of an audio signal waveform. The first is a method that separates and transmits or stores memo QK (repeated pitch) information and spectrum information, as typified by the LPG method. This method (Japanese Patent Laid-Open No. 56-4194, etc.) involves manually capturing and transmitting or storing the repeated pattern.

However, since the first method is based on the basic premise of extracting pitch information from repeated waveforms that have pitch information in voiced parts, if pitch information extraction fails, the original voice note waveform is It has one drawback: it produces a lot of noise when played back, and it impairs the clarity of the voice.

On the other hand, in the second method, most of the pitch information must be manually operated in order to extract it accurately, so it is difficult to compress it in real time.

The purpose of this 1IIJli is to repeat the input signal waveform (
It is an object of the present invention to provide a waveform compression device which causes little deterioration of a reproduced signal waveform even when pitch information (pitch information) of an audio signal waveform cannot be detected and can perform compression in real time.

This generation performs compression by outputting the unit waveform of the repetition, its time length, and the number of repetitions only when a repetition of the input signal waveform is detected, and when no repetition is detected. The feature is that the input signal waveform is output as is and no compression is performed. Therefore, since compression 4 is not performed when repetition cannot be detected, there is little deterioration such as a decrease in 87N of the reproduced signal liquid form or a decrease in clarity, and the dependence of the presence or absence of repetition on the compression of 41'il By reducing the degree, the amount of time required for the determination is relaxed, and manual determination is no longer necessary, allowing for more time-efficient processing.

An embodiment of this beak will be described below with reference to the drawings.

The first diagram shows the configuration of a waveform compression device according to the -111/IIA example of lI@, and a sampled input signal, such as an audio signal, is applied to the input terminal fK. This input signal M is applied to a repetition determiner 2 and a data processor 1. Repetition determiner 1 is composed of, for example, an autocorrelator, and determines whether or not there is repetition in the waveform of the input signal.It outputs signal 1 every time it detects repetition, and when it cannot detect repetition, it outputs signal 1 during that period. medium signal f
Continuously outputs.

Of the outputs of the repetition determiner 1, the signal ``is inputted to a counter, and the number of repetitions M of the input signal waveform or similar waveform is counted.The data of this repetition number M and the signal ``are inputted to the counter. -1 "is data processor IK
is input.

When the data processor 1 is given the signal 1, it sequentially outputs the repetitive unit waveform of the input signal m and its time length information to the output terminal e, and then temporarily stops the output. Then, the counter outputs information on the number of repetitions M that has been made up to that point to the terminal -
Transfer to.

Note that the repetition determination-2, data processor 1, and counter 4 operate with one clock pulse CILK9 generated by the clock oscillator I.

Next, a concrete example of the operation of this embodiment will be explained using a gm diagram. The purpose of II is to schematically show the waveforms of each part of ill. The waveform of the input signal M is shown continuously in □ for convenience, but the waveform of the input signal M is shown continuously in □ for convenience.
It is sampled with a period of L, and each sample value must be lI! digitized accordingly.

Now, the repetition judger 1 detects whether or not the □ waveform of the input signal is repeated along the time axis direction indicated by the arrow t.
(and the waveform at time t).

Tomu, Dogaoka - or something similar.

Therefore, the repetition determination amount S stops outputting the signal V at time t, and generates one signal 1. Waveforms that are the same or similar.

Mu1. Each one of these is called a unit liquid form with nine repeats.

At this time, the repetition judgment Wk1 is the time length (frame length) of this unit liquid type expressed by the number N of clock pulses CK input during that time (1irxll in the figure).
The waveform is temporarily stored in the built-in memory along with the waveform information. The repetition determiner 1 continues to determine the presence or absence of the waveform of the input signal M by referring to the waveform information of the waveform M or M, but in this example, the waveform M8 following the waveform M is used. The same or similar judgment is made for the waveform M, and then the waveform M appearing following the waveform M.

No similarity can be found for waveforms with the same frame length as the frame length of . Therefore, the repeated judgment goodwill is waveform 2. Mu1. tt * ' * 4
The signal 1 is generated at 'a, and the signal -f starts to be generated at the end time t of the waveform m. The counter 4 is counting the signal 1 during this time, and the count value at time t4 is the number of consecutive identical or similar waveforms up to that point, that is, the number of repetitions M
(M!4 in this example).

The data processor 1 has a built-in memory that stores the waveform of the input signal for a predetermined amount of time.

The contents of the memory are continuously output for a certain period of time as shown in B in response to the input signal. This extended delay time is set to be longer than the maximum possible frame of the input signal waveform, and when τ is expressed as the number of clock pulses CK, it is DEN, and - is Doll. The data set a set amount 1 sends an output signal such as C to the output terminal l based on the signal [, fK. That is, the period CFmI□s during which the signal - is given) 1d and f = @ t
During the period of reverberation (D-N) after becoming @, the 0-order Km outputs the liquid form of eccentric B one after another from the memory as it is, its weight, that is, the information of the liquid form in the human power system. After outputting the identification code FIIC to distinguish between the shape information and the next (((repeat information)), the first information N of the frame is output.

Output is stopped until F gate @ e @ is reached. Then, when it becomes f mouse * o @ again, after repeatedly outputting the information of the fixed number M, from the time t when it becomes FW'O"K, (D-N
) After a period of time has elapsed, the signal wave all
(Information on the liquid fist in the input signal) is output as is.

In this way, the waveform of the input signal K11Il-ma.

During the period in which similar waveforms or similar waveforms are repeated (during the period in which the repetition is detected by the repetition determiner 2), the information of the repeated unit waveform and the P .

Since the output can be stopped except during the period when each of the N and M information is output, waveform compression can be performed efficiently, and the transmission KIIL and transmission bit rate can be greatly reduced.

Also, if you want to store the output waveform in memory.

As shown in No. 311, by shortening the output stop period and allocating the memory, the memory capacity can be used efficiently and it is economical.

As explained above, according to the present invention, not only is it possible to compress real time, but even if there is repetition in the input signal waveform but the repetition cannot be detected, it is possible to There is an advantage that the original odd waveform can be reproduced with almost no deterioration in the readout 11 from the memory. In addition, repeated judgment 1) Kl required performance is loose 1
IJ! Ru.

[Brief explanation of the drawing]

No. ** is a configuration diagram of an embodiment of the present invention, and FIG. 8 and SS are waveform diagrams for explaining its operation. Applicant's agent Takeshi Suzue Diagram 1

Claims (1)

[Claims] A determination means for determining the presence or absence of a repetition of the input □Power Recruitment □Liquid fist on the time axis, and a determination means for detecting repetition i.
a stitch count means for counting the number of repetitions of the repetition, and a unit waveform of the repetition in the human input signal waveform and this unit waveform □ when the repetition is detected by the judgment means 1;
The length of time and the number of times counted by the marking means and the ship's side are output, and if the judgment means does not detect 〈9 occlusions, then the previous information during the period in which the repetition was not detected is outputted. □ A waveform compression device characterized by comprising: means for outputting input signal waveforms; and □.