DE102014007712A1 - Method for the semi-automatic generation of a rhythmic output signal from an input signal comprising individual pulses, apparatus for carrying out such a method and program product - Google Patents

Abstract

A method for automatically generating a rhythmic output signal from an input signal (ES) having single pulses (EP, EP ') is described. The method comprises the following steps: 1. Generating a trigger signal (TS, TS ') for each individual pulse (EP, EP') which exceeds a predetermined signal strength. 2. Measuring the time interval length (.DELTA.t1) between each two consecutive trigger signals (TS, TS '), wherein the time interval terminating trigger signal (TS') further defines a start time. 3. Calculating a delay time (1/2 Δt1) which is a multiple of the last measured time interval length (Δt1), the value of the multiple being between 0 and 1. 4. Generating and outputting the output signal (AS), which has for each trigger signal (TS, TS ') a simultaneous first output event (EA, EA') and second output events (ZA), wherein until the termination of the generation of the output signal (AS) every other output event (ZA) is output delayed by the delay time (1/2 Δt1) after the last start time. The method allows a musician to accompany himself rhythmically, with the musician dictating the clock speed.

Description

The invention relates to a method for the semi-automatic generation of a rhythmic output signal from a single-pulse input signal according to claim 1, a device for its implementation according to claim 7 and a program product according to claim 10.

In particular, in solo musicians, but also in smaller groups of music, which occur without drummers or percussionists, there is often the desire to accompany themselves rhythmically. There are currently two options for this:
On the one hand, there are programmable rhythm computers that specify the speed and type of rhythm. Such rhythm computers have the advantage that the using musician does not have to take care of them during his play, since the accompaniment rhythm is generated completely automatically. The disadvantage is that the speed is constant over the entire piece played. This leads to a sometimes somewhat artificial and "sterile" overall impression, which can stand in a certain contrast to the "handmade" character of a live performance. In addition, the musician is tied to the selected speed over the duration of the played piece of music.

Furthermore, it is possible to play a simple rhythm, especially in the form of a bar, yourself. For musicians who need both hands to operate their instrument, especially for guitarists, so-called stompp boxes are known for this purpose. Such a stomp box essentially consists of a housing in which a signal generator in the form of a microphone or a piezoelectric sensor is accommodated. About an output jack, the signal generated by the signal generator can be tapped and processed, in particular amplified, or even changed electronically. The beat speed is generated here by the musician himself. This usually results in a certain (often unwanted) fluctuation of the tempo, which usually leads to a more natural overall impression. On the other hand, the musician can willingly change the speed within a piece. A disadvantage of this type of self-accompaniment, however, is that it is not possible for most musicians (which are usually not trained percussionists in this case) to play more complex rhythms, such as "shuffled" rhythms, which makes this type of rhythmic self-accompaniment something can seem monotonous.

On this basis, the present invention has the object to provide a method for generating a rhythmic output signal, which overcomes the disadvantages of the prior art just described.

This object is achieved by a method having the features of claim 1. An apparatus for carrying out this method is specified in claim 7. A program product with a program loadable on a data processing device which enables the data processing device to carry out the method according to the invention is specified in claim 10

According to the invention, a rhythmic output signal is generated partially automatically from an input signal having individual pulses. In this case, the input signal having the individual pulses is generally the "knocked-out" clock, wherein the input signal can be provided in particular by a stompp box. To further process the input signal digitally, a trigger signal is first generated for each individual pulse which exceeds a predetermined signal strength.

According to the invention, the rhythmic output signal comprises two types of output events, the output event being any type of signal which can be converted into an audible sound or an audible sound.

The first output events are output at the same time as the trigger signals generated from the individual pulses of the input signal. It should be emphasized that the term "at the same time" should also apply to minimally delayed events since, due to the necessary electronic data processing, there may be a minimum delay in the range of microseconds or milliseconds. It should also be emphasized that the usually electronically generated output events - usually one sample each - usually have a length that exceeds the length of the trigger signals. The term "at the same time" is therefore to be understood as meaning that the start time of the respective output event coincides with the trigger signal generated from the incoming single pulse in time (or is minimally delayed in time to this).

The second output events are generated automatically and are output between the first output events. The time of the output is calculated by means of a processor, the calculation taking place according to the following scheme: The length of the time interval between in each case two consecutive trigger signals is measured and stored temporarily, the triggering signal terminating the time interval furthermore defining a start time. From the last measured time interval length becomes a Delay time calculated, which is a multiple of the last measured time interval length, which is the value of the multiple between 0 and 1 and preferably 1/2 or 2/3. The time of the output is delayed by the delay time after the last start time.

In principle, several second output events can also be generated and output per time interval, it being possible in this case to calculate more than one delay time per preceding time interval. For the sake of clarity, however, only one second output event per preceding time interval will be discussed below, which should also be the most frequent application case.

As a result, a relatively complex output rhythm can be generated, which adjusts itself to the speed of the musician and which is very easily generated by the musician by "knocking" the clock.

Preferably, the output events are stored samples, and it is further preferable that the sample for the first output events be different from the sample for the second output events.

It is further preferable that the musician selects from a number of different samples for both the first output events and the second output events by means of a selector switch.

The method can be dynamic in terms of velocity, so that at least the first output events have a variable volume, which depends on the amplitude of the associated output signal.

Since the method according to the invention is intended in particular for live performances, the method is preferably carried out by a device specially designed for this purpose, which has an input for the input signal, usually in the form of an input socket, an output for the output signal, as a rule Form of an output jack - and an electronic circuit (electronics unit), which carries out the steps just described has.

However, the method may also be performed by a freely programmable computer or other data processing device to which a corresponding program has been loaded.

The invention will now be explained in more detail with reference to an initial example with reference to the figures. Hereby show:

1 : a schematically illustrated timing of an embodiment of the method according to the invention and

2 FIG. 2: a schematic block circuit diagram of an exemplary embodiment of a device according to the invention.

First, it should be emphasized that both figures are highly schematic and that both figures show only one embodiment, to which, however, numerous variations are possible. It should also be noted that the reference symbols Δt _{1 ,} Δt ₂ , Δt _{3 are} used both for the time intervals and for their time length (time interval length), since this appears clearer.

It is first on the in 2 illustrated device received, with reference also to the 1 is taken.

The device 10 has an input jack 12 for supplying a signal, preferably an analog signal. Furthermore, the device 10 an output jack 32 to output an analogue output signal. In operation, the input jack is usually connected to a stompp box or similar signal generator while the output jack 32 is connected to an amplifier, which in turn is coupled to a speaker. Furthermore, the device 10 various controls and switches, which will be discussed later. It should be emphasized that in the following the term "controller" will be used in a rather colloquial manner, namely, as the term "volume control" is used in connection with a radio or an amplifier. Controller is not to be understood in such a way that a real control circuit must necessarily be present. The input jack 12 is via an electronics unit described below with the output jack 32 indirectly connected.

The input jack 12 is with an amplifier 14 connected, which in turn with a discriminator 16 and a first digital-to-analog converter. It's one with the discriminator 16 connected sensitivity regulator 18 provided, with the aid of the sensitivity of the device can be adjusted to allow the musician to determine from which "footfall" an incoming input pulse is to be utilized. The discriminator 16 generates upon triggering the - in the illustrated embodiment adjustable - trigger threshold TT each have a trigger signal TS, TS ', ... and forwards this to a computing unit 24 which is bidirectional with a sample memory 26 connected is. The arithmetic unit 24 outputs the signals generated by it either to the aforementioned first digital-to-analog converter or to a second digital-to-analog converter 29 which sends its signals via a mixer 30 to the output jack 32 pass on. Each of the two digital-to-analog converters 28 . 29 is a volume control 20 . 22 assigned. Furthermore, a sound selector switch 34 and a rhythm selector 36 provided, which with the arithmetic unit 24 are connected.

It is at this point to emphasize that many of the elements just described, in particular the arithmetic unit 24 and the sample unit 26 can be summarized in a common microchip so that they do not have to be formed as physically separate elements, but merely as functional elements.

The course of the method according to the invention will now be described with reference to the 1 and 2 explains:
The 1 schematically shows the input signal ES, which in the input jack 12 is fed and the output signal AS, which at the output jack 32 can be tapped and strengthened. The 1 is not to scale, in particular, the individual pulses EP, EP '... the input signal ES are too wide, so shown too long in time. In 1 is shown for better understanding a "song beginning".

About the input jack 12 an individual signal ES having individual pulses is fed. The individual pulses EP, EP ', EP''... are generated here by a musician, for example by means of a so-called stomp box. The time intervals between two adjacent individual pulses are mostly relatively constant, but may vary somewhat over time (as shown), and these time intervals may vary over the entire duration of a track being played, namely when the musician deliberately accelerates or slows down the track. Furthermore, the individual impulses EP, EP ', EP "... usually have different amplitudes A from one another. This too may be due to a deliberate influence on the musician or even unwillingly justified.

As already mentioned, the input signals ES, ES ', ... are first the amplifier 14 fed. This gives a correspondingly amplified signal on the one hand to the discriminator 16 and on the other to the first digital-to-analog converter 28 or (not shown) a separate amplifier connected downstream of the first digital-to-analog converter. By means of the sensitivity regulator 18 becomes the trigger threshold TT of the discriminator 16 set. The musician adjusts the trigger threshold in such a way that willfully generated individual impulses (generated for example by the occurrence of a foot on a stompp box) from the discriminator 16 be recognized as "allowed". As soon as the trigger threshold TT is exceeded, the discriminator outputs 16 a trigger signal TS, TS ', TS''; ... to the arithmetic unit 24 further. Here's what happens: first, the arithmetic unit reads 24 a first sample from the sample memory 26 (which sample should be selected can be selected by the musician using the sound selector 34 preset) and at the same time as the trigger signal TS, TS ', TS ", ... (or minimum technical delay) are input, this first sample is sent to the first digital-to-analog converter 28 Furthermore, which an analog signal, which further the amplitude A of the associated single pulse EP, ... EP ', ... and one by means of the first volume control 20 adjusted value, to the mixer 30 (which may also include a preamplifier) on which the now analog signal, namely the first output event EA to the output jack 32 passes.

Furthermore, each trigger signal TS sets a time interval measurement in progress, which will now be explained with reference to the "song start". With the first trigger signal TS begins a first time interval .DELTA.t ₁ , which lasts until the next trigger signal TS '. The arithmetic unit 24 measures the length of this time interval Δt ₁ and calculates a multiple thereof, the value of the multiple lying between 0 and 1. In the embodiment shown, the multiple is ½, another preferred value is 2/3. The value can be selected by means of the rhythm selection switch 36 to be selected. 'Ends, as already stated, the first time interval .DELTA.t _1, starts a new time interval At _2, which until the next trigger signal TS' the second trigger signal TS continues', and further defines a start time S. The arithmetic unit 24 Now, after the expiration of the multiple of the last measured time interval (here 1 / 2Δt ₁ ) after the last start time - here S -, a second sample (which contains the arithmetic unit 24 from the sample memory 26 reads out) to the second digital-to-analog converter 29 which, accordingly, an analog second output event ZA to the mixer 30 passes, so this second output event ZA at the output jack 32 is issued.

This process is repeated again and again, except for at start and end (the start just described) each trigger signal (EP ', EP'',EP''', EP '''') both the beginning and the end of a Defines time interval and each also defines a start time S, S ', S''. This is explained again with reference to an example: the trigger signal TS '' determines the start of the time interval Δt ₃ , the end of the preceding time interval Δt ₂ and the start time S '. After the elapse of ½Δt ₂ after the start time S ', the second output event ZA' is output. The end of the time interval Δt ₃ is determined by the trigger signal TS ''', which in turn is also the start time S''for the next delay time (½Δt ₃ ), etc.

In general, it is undesirable that after the end of a song, an output event is issued, so there may be a possibility of how the music player aborts the process. For this purpose, for example, a separate button may be provided (not shown). Another possibility would be that with two trigger signals, which follow each other within a short, defined time, the method by the arithmetic unit 24 is canceled.

In general, it will be preferable to perform the method in a device, for example, as described above, wherein the device thus has at least one input and at least one output and at least one arithmetic unit. In principle, however, it is also possible to run the method in a computer by means of special software, which maps the method just described.

LIST OF REFERENCE NUMBERS

10

contraption

12

input jack

14

amplifier

16

discriminator

18

sensitivity control

20

first volume control

22

second volume control

24

computer unit

26

Sample storage

28

first digital-to-analog converter

29

second digital-to-analog converter

30

mixer

32

output jack

34

Sound selector

36

Rhythm selector

TT

trigger threshold

TS

trigger signal

IT

input

AS

output

EP, EP '...

single pulses

EA, EA '

first initial events

ZA, ZA '

second output events

Claims (10)

Method for the semi-automatic generation of a rhythmic output signal (AS) from an individual input signal (EP, EP ', EP'',EP''', EP '''') comprising the following steps: - generating a trigger signal (TS, TS ', TS'',TS''', TS '''') to each individual pulse (EP, EP ', EP'',EP''', EP ''''), which a predetermined signal strength (trigger threshold TT ), measuring the time interval length (Δt ₁ , Δt ₂ , Δt ₃ ) between any two consecutive trigger signals (TS, TS ', TS'',TS''', TS ''''), which is the time interval (ΔT ₁ , Δt ₂ , Δt ₃ ) terminating trigger signal (EP ', EP'',EP''', EP '''') further defines a start time (S, S ', S'',S''') Calculating at least one delay time, which is a multiple of the last measured time interval length (Δt ₁ , Δt ₂ , Δt ₃ ), wherein the value of the multiple lies between 0 and 1. - Generating and outputting the output signal (AS), which until the abort of the generation of the output signal (AS) comprises: - for each trigger signal (TS, TS ', TS'',TS''', TS '''') a simultaneous first output event (EA, EA ', EA'',EA''', EA '''') - second output events (ZA, ZA ', ZA''), each second output event (ZA, ZA', ZA '') ) is output delayed by the delay time after the last starting time (S, S ', S''). Method according to Claim 1, characterized in that each output event (EA, EA ', EA'',EA''', EA '''', ZA, ZA ', ZA'') is a stored sample. Method according to Claim 2, characterized in that the first output events (EA, EA ', EA'',EA''', EA '''') comprise a first sample and the second output events (ZA, ZA ', ZA'') are a second sample different from the first sample. Method according to one of the preceding claims, characterized in that the multiple is 1/2. Method according to one of claims 1 to 3, characterized in that the multiple is 2/3. Method according to one of the preceding claims, characterized in that the amplitudes (A) of the individual pulses (EP, EP ', EP'',EP''', EP '''') are measured and the output amplitude of each first output event (EA, EA ', EA'',EA''', EA '''') depends on the amplitude of the underlying individual pulse (EP, EP ', EP'',EP''', EP ''''). Contraption ( 10 ) for carrying out the method according to one of claims 1 to 6, wherein the device has an input, in particular in the form of an input socket ( 12 ), an output, in particular in the form of an output socket ( 32 ); and an input and output connecting electronics unit that performs the method. Apparatus according to claim 7, characterized in that the electronic unit is a computing unit ( 24 ) and a sample memory ( 26 ) having. Device according to one of claims 7 or 8, characterized in that it comprises at least one sensitivity regulator ( 18 ) for the input signal (ES). Program product having a program loadable on a data processing device, which enables the data processing device to carry out the method according to one of claims 1 to 6.

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