JP2500876Y2 - Code progress analyzer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a chord progression analyzer, and more particularly to a technique for automatically analyzing the format of a piece of music from given chord progression information.

[Background] Musical works can only be perceptually understood by people with little musical knowledge. However, in order to enjoy the work deeply, not only sensory understanding but also intellectual understanding based on musical theory is necessary. For example, if the music format can be understood intelligently, it becomes possible to perceptually recognize the common features through appreciation of music having a similar format.

Unfortunately, acquiring musical knowledge is generally time consuming and labor intensive. Therefore, there is a demand for a device that can easily deepen the user's musical understanding by automatically analyzing music works.

[Object of the Invention] Therefore, an object of the present invention is to provide a chord progression analyzer that automatically analyzes the format of a song from the chord progression of the song.

[Summary of the Invention] In order to achieve the above object, the present invention divides the chord progression information of a music piece given by the chord progression imparting means into a plurality of equal-length sections, and divides the divided sections into sections. It is characterized in that the degree of coincidence of chord progression information is calculated by the music format analysis display means and the format of the music is analyzed and displayed.

[Embodiment] An embodiment of the present invention will be described below with reference to the drawings.

The overall structure is shown in FIG. 1 and the general flow is shown in FIG. In this embodiment, the chord progression information and the length of the section (block) are input from the input device 2 (see FIGS. 2 and 2).
-1, 2-2). The input chord progression information is stored in the chord progression memory 4. The CPU 1 divides the music into a plurality of blocks having the same length by the length of the given section, and calculates the degree of coincidence of chord progression information between the blocks (2-
3). The calculated coincidence data is the coincidence data memory 5
Placed in. Further, the CPU 1 generates the structural information of each block based on the calculated matching score data (2-
4). The generated structure information is stored in the structure information memory 6. Finally, the CPU 1 displays the generated structural information on the display device 3 in the form of music (2-5).

FIG. 3 shows a detailed flow of calculating the degree of coincidence. In this flow, CN ₀ is the total number of chords, CN is the chord name, and bar is the length of the block expressed by the number of bars (for example, 4 bars). V _ij is the chord progression of the i-th block and j
Indicates the degree of matching of chord progressions in the second block. The calculation of the degree of coincidence is performed in the order of V ₁₁ V ₁₂ ...... V _1n , V ₂₂ ...... V _2n , ...... V _nn .

In this flow, it is assumed that there is one code per bar, and the value obtained by dividing the number of times the corresponding bar codes of the i-th block and the j-th block match by the length of the block is used as the matching degree function. . Therefore, V becomes "1" when all the codes match. For example, V _ii is “1”.

In step 3-1, the total number n of blocks of music is calculated. If it is not divisible, cut it down. 3-2 is initialization of the block number of i in the i-th to j-th inter-block coincidence degree V _ij , and 3-3 is initialization of the block number of j. 3-4 is the first bar number of the i-th block and j
It is the calculation of the first bar number of the second block. 3-5
Is initialization of the counter v of the code matching number, and 3-6 is initialization of the bar number k in the block. 3-7 is a code comparison, and the counter v is incremented each time they match (3-8). In 3-11, the number of code matches between blocks stored in the counter v is divided by the block length bar to calculate V _ij . As it can be seen from 3-12,3-13,3-4, for a particular i blocks, by comparing the block to _{j = i~n, V ii, V} i, of the _{i + 1} ...... V _in Seeking the degree of coincidence. In V _ij , the block of i−1 or less is not used as j is based on V _ij = V _ji .

Therefore, the desired V _ij is V ₁₁ V ₁₂ V ₁₃ ...... V _1n Is. When i of V _ij exceeds 3 in 3-15, all the above V _ij are obtained.

FIG. 4 shows a detailed flow of structure information generation. The degree of matching V of the j-th block with the i-th block described above
The purpose of this flow is to convert _ij into the structural information h _j of the j-th block. In the case of this flow, the structural information h _j of the first block is always “1”. With _respect to this first block, the block having the degree of coincidence V _ij of 100% is structural information h _j.
Is assigned as “1”. The structural information of the block having the degree of coincidence V _ij of 70% or more is “1.5”. Further, the structural information of "2" is given to the block having the smallest number among the blocks having the degree of coincidence of less than 70%. Similarly, all blocks that 100% match the structural information of "2" are "2".
The structural information of is 70% to 100% of the block is structural information of "2.5".

Therefore, a, a ', which are often used in the form of music,
When compared with the symbolic expressions such as b, the correspondence of the h _j normal expression 1 a 1.5 a ′ 2 b 2.5 b ′ 3 c is established. That is, in the case of the flow of FIG. 4, a block that is 100% identical to a certain block is evaluated as a block having the same structure in terms of code progression, and a block that is 70% to 100% identical is evaluated as a modified block. A block having a degree of coincidence of less than is evaluated as a block having an independent structure.

Fl _i indicated by 4-1 in FIG. 4 is a flag indicating whether or not structural information has already been added to the i-th block (fl _i = 1) (fl _i = 0). In 4-2, 4-3, and 4-4, the first block among the blocks whose structure information is not determined is searched. Fl of 1 to n when j = n + 1 in 4-5
_Since all _j are "1" for confirming the structural information, the processing is ended. I = j in 4-6, and fl _j = between j = 0 and n
When it is 0, the structural information of the j-th block is set by the value of the degree of coincidence V _ij of the j-th block with respect to the i-th block (4-8 to 4-14).

FIG. 5 shows an operation example. This example was analyzed based on the chord progression of Yuming's "Graduation Photograph", and the analysis result in blocks of 4 bars was aaa'bcaa'bca'dda '.

In the above embodiment, the number of chords per bar is assumed to be 1 in the calculation of the degree of coincidence, but it is easy to modify it so that it can be applied to other cases (minimum chord duration time). Or, the code comparison may be performed every one-hundredth of that time). Further, instead of comparing the names of chords, the comparison may be performed at the level of the chord constituent sounds. Also,
Although the chord progression is input from the input device in the above embodiment, the chord progression may be obtained by means of extracting the chord progression from the melody of the song (for example, Japanese Patent Application No. 62-152348 relating to the present applicant). Use the device disclosed in No.

[Effect of Device] As described in detail above, by using the chord progression analyzer according to the present invention, even a person with no musical expertise can easily know the format of the music, and how to enjoy the music. Can be doubled. Moreover, it is a very useful tool for learners who want to acquire musical knowledge.

[Brief description of drawings]

FIG. 1 is an overall configuration diagram of a chord progression analyzer according to an embodiment of the present invention, FIG. 2 is a flowchart showing the overall operation of the embodiment, FIG.
FIG. 5 is a flow chart of structural information generation, and FIG. 5 is a diagram showing an analysis example according to the embodiment. 1 ... CPU, 2 ... input device, 4 ... code progression memory, 5 ... coincidence data memory, 6 ... structure information memory.

Claims (1)

(57) [Scope of utility model registration request] 1. A chord progression giving means for giving chord progression information of a piece of music, a section dividing means for dividing the piece of music into a plurality of sections of equal length, and the sections divided by the section dividing means,
A chord progression analysis machine comprising: music format analysis display means for analyzing and displaying the format of the music by calculating the degree of coincidence of the chord progression information.