System for generating playable structured practice files for string instruments using constraint-based pattern synthesis

Abstract

(Independent system) System for generating playable structured practice files for a string instrument, including: - a processor and a memory connected to the processor containing instructions; - an input module (101) configured to receive user input and to transform the input into a set of quantifiable parameters, including at least tempo, rhythmic subdivision, technique type and difficulty level; - a pattern database (102) containing abstracted musical patterns, each indexed with metadata that includes tonal, rhythmic, technical and physical playability attributes; - a retrieval module (103) configured to retrieve patterns from the pattern database based on parameters derived from the input module; - a synthesis module (104) configured to combine and transform retrieved patterns into at least one candidate sequence; characterized in that the system further comprises: - a constraint module (105) configured to derive dynamic physical playability constraints as a function of the quantifiable parameters, wherein the constraints represent physical properties of the target instrument and biomechanical limits of the performer and include at least: (a) a string-specific maximum fret position, derived from the physical construction of the instrument, (b) a maximum grip span as a function of the difficulty level, derived from the biomechanical reach of the human hand, (c) a maximum positional shift along the fingerboard per time interval as a function of tempo and technique type; - a validation module (106) configured to check each candidate sequence against all constraints derived from the Constraint module and to reject or modify sequences that violate at least one constraint; - an output module (107) configured to encode validated sequences into an instrument-specific binary notation format that includes at least string assignment, fret position, time value and technique annotation for each note.

Description

1. Technical field

[0001] The invention relates to a computer-implemented system for generating structured practice data for stringed instruments, in particular guitar.

[0002] The system generates instrument-specific notation files that take into account and enforce the physical playability limitations of the target instrument - including fret geometry, string spacing and biomechanical finger spans - as technical constraints. 2. State of the art

[0003] Known systems for generating musical content typically focus on content creation without ensuring physical performance by a human interpreter. These include, in particular: - Algorithmic composition systems (e.g., rule-based or Markov chain-based melody generators) that produce sequences of notes without instrument-specific restrictions; - Tablature editors and practice software (e.g., Guitar Pro, TuxGuitar, Yousician) that display and play existing notation data but do not synthesize new playable practice material taking physical limitations into account; - Learning platforms with practice libraries (e.g. JustinGuitar, Fender Play) that provide static, author-generated content without parametric on-demand generation.

[0004] Known systems exhibit the following technical deficiencies: - They generate note sequences without regard to instrument-specific physical limitations (e.g. maximum finger span, string and fret-specific ranges); - They require manual post-processing by a specialist to ensure playability; - They do not model feasibility as a function of several interacting physical parameters such as tempo, note density, and required positional movement along the fingerboard.

[0005] This often results in machine-generated output that is physically unexecutable or requires subsequent correction. 3. Technical problem to be solved

[0006] The invention is based on the technical problem of providing a system that automatically generates structured practice data for stringed instruments that: - are adapted to user-defined technical parameters; - are structurally valid and parametrically consistent; - are physically executable on the target instrument by a human performer - without manual post-processing or correction. 4. Solution - Summary of the invention

[0007] The task is solved by a computer-implemented system that retrieves abstracted musical patterns from a structured database, recombines them under dynamically calculated physical playability constraints, and encodes the result into an instrument-specific binary notation format.

[0008] Playability is enforced by a constraint module that dynamically derives physical limitations of the target instrument – ​​including string-specific fret spacing, maximum permissible finger span, and tempo-dependent positional movement – ​​as technical boundary conditions from the input parameters.

[0009] Generated sequences are checked against all derived restrictions by a validation module before output, so that only physically executable material is output as a file. 5. Detailed description

[0010] The following description explains the structure and function of the system using a preferred embodiment as an example. However, the invention is not limited to this embodiment; the claims define the scope of protection.

[0011] Note: The drawings referenced in this description ( Fig. 1 - System architecture, Fig. 2 - Constraint evaluation) are attached as separate sheets. 5.1 System architecture (Fig. 1)

[0012] The system comprises the following functional modules, which run on a processor with associated memory: - Input module (101): Receives user input and converts it into quantifiable parameters. - Pattern database (102): Stores abstracted, indexed musical patterns. - Retrieval module (103): Retrieves suitable patterns from the database based on the derived parameters. - Synthesis module (104): Combines and transforms retrieved patterns into candidate sequences. - Constraint module (105): Derives dynamic physical playability restrictions from the input parameters. - Validation module (106): Checks generated candidate sequences against the derived constraints. - Output module (107): Encodes validated sequences into an instrument-specific binary notation format. 5.2 Data Acquisition and Pattern Representation

[0013] The system processes digital notation files (e.g., in Guitar Pro binary format) as input data. These are transformed into a normalized symbolic representation, including: - Pitch information (MIDI note values); - Time structure (note values, time signatures, tempo); - Instrument-specific position assignments (string and fret position for each note on the fingerboard). 5.3 Pattern Extraction and Abstraction

[0014] The retrieval module (103) segments the normalized data into reusable musical patterns at bar and phrase level (2-4 bar groups).

[0015] Each pattern is converted into a parameterized representation that: - preserves structural relationships (interval sequences, rhythmic relationships, relative fretboard positions); - uses a source-independent representation that allows reuse in any musical context.

[0016] The resulting patterns are stored in the pattern database (102). 5.4 Pattern Indexing

[0017] Each stored pattern is tagged with machine-readable metadata, including: - tonal attributes (fundamental tone, scale type); - rhythmic properties (note density, degree of subdivision); - technique-related features (e.g., sweep picking, legato, tapping, bending); - physical playability parameters (occupied frets, occupied strings, maximum finger span within the pattern, required positional shift). 5.5 Input processing

[0018] The input module (101) receives structured or text-based user input and transforms it into a set of quantifiable parameters, including: - Pace in beats per minute; - rhythmic subdivision (e.g. eighth notes, triplets, sixteenth notes); - Target grade density; - Technique type (e.g. Alternate Picking, Sweep, Legato); - Difficulty level; - Instrument tuning and number of strings.

[0019] If the input is incomplete, the input module fills in missing parameters with default values, which are optionally derived from an assigned parameter profile. 5.6 Pattern retrieval and combination

[0020] The retrieval module (103) retrieves from the pattern database (102) those patterns whose indexed metadata is compatible with the derived parameters.

[0021] The synthesis module (104) combines the retrieved patterns into a candidate sequence. The combination includes: - Transposition to the target key; - Adapting the time structure to the target pace; - Structural rearrangement to comply with formal requirements (e.g., number of bars, repetition structure). 5.7 Constraint-based playability models (Fig. 2)

[0022] The Constraint module (105) derives a set of dynamic physical playability constraints from the input parameters. These constraints represent measurable physical properties of the target instrument and human hand motor skills: (a) String-specific fret range: A maximum fret position is defined for each string of the instrument, resulting from the instrument's physical construction. Thus, the maximum achievable fret position on the high strings (strings 1-2) of a standard guitar is up to fret 24, while on the low strings (strings 5-6) a lower maximum value applies due to the body geometry (e.g., fret 21). Notes beyond these physical limits are rejected by the system. (b) Grip span limitation: The maximum permissible span between the lowest and highest frets to be gripped simultaneously or sequentially is limited as a function of the difficulty level. This limitation reflects the biomechanical reach of the human hand. In a preferred embodiment, the maximum span is 4 frets at a low difficulty level and 6 frets at a high difficulty level. (c) Tempo-dependent position shift: The maximum permissible shift of the fretting hand position along the fingerboard per time interval is limited as a function of tempo and technique type. At high tempos, only small position shifts are permissible, as the time available for physical hand movement decreases. (d) Tempo-dependent note density: The maximum number of notes produced per measure is limited as a function of tempo and rhythmic subdivision to avoid physically impossible note clusters. (e) Transition check: For each pair of consecutive notes or fingerings, it is checked whether the required change of position is physically feasible within the available time interval. Transitions that exceed the permissible movement per unit of time are rejected. 5.8 Validation and Iteration

[0023] The validation module (106) checks each candidate sequence generated by the synthesis module (104) against all constraints derived by the constraint module (105).

[0024] Sequences that violate one or more restrictions are either modified (e.g., by adjusting individual fret positions within the allowed limits) or discarded and regenerated by the synthesis module. This process is repeated iteratively until a sequence is obtained that satisfies all restrictions. 5.9 Output encoding

[0025] The output module (107) encodes validated sequences into a structured, instrument-specific binary notation format. In a preferred embodiment, the Guitar Pro binary format (.gp) is used, which encodes the following technical data for each note: - String assignment and fret position; - Time value and position in the beat; - instrument-specific technique annotations (e.g. hammer-on, pull-off, slide, bend); - Tempo information and time signature changes.

[0026] The encoding ensures syntactic correctness of the binary format as well as direct machine readability by playback software. 6. Technical effect

[0027] The system achieves the following technical effects: - Generation of instrument-specific notation data that can be physically executed on the target instrument without manual post-processing; - Elimination of invalid outputs by enforcing physical limits of the instrument and biomechanical limits of the performer as technical constraints; - Dynamic adjustment of restrictions as a function of input parameters, ensuring physical feasibility with different combinations of tempo, difficulty, and technique; - Encoding the results into a binary, machine-processable notation format with instrument-specific position information. 7. Examples of Implementation 7.1 Example 1 - Low difficulty, moderate pace

[0028] A user specifies the following parameters: - Tempo: 80 BPM - Rhythmic subdivision: Shuttle (triplet eighth notes) - Technique Type: Alternate Picking - Difficulty level: Beginner - Key: A minor pentatonic scale, standard tuning

[0029] The constraint module derives: - Maximum grip span: 4 frets - String-specific fret spacing: 21st fret (low strings), 24th fret (high strings) - Position shift: max. 2 frets per measure at 80 BPM - Maximum note density: 8 notes per bar (triplet eighth notes at 80 BPM)

[0030] The retrieval module selects compatible patterns, the synthesis module combines them, and the validation module confirms compliance with all restrictions. The output module encodes the sequence as a .gp file with correct string and fret positions, tempo annotation, and technique instructions. 7.2 Example 2 - High difficulty, high pace

[0031] A user specifies the following parameters: - Tempo: 160 BPM - Rhythmic subdivision: sixteenth notes - Technique type: Sweep picking - Difficulty level: Advanced - Key: E minor, standard tuning

[0032] The constraint module derives: - Maximum finger span: 6 frets - Additional restriction for sweep picking: only one diatonic chord shape per measure, string crossings must be strictly sequential. - Position shift: max. 3 frets per measure at 160 BPM - Maximum note density: 16 notes per bar (sixteenth notes at 160 BPM)

[0033] The validation module rejects candidate sequences where the sweep motion includes non-sequential string crossings or where the required positional shift between successive chord shapes exceeds the allowed movement per unit of time. After iterative adjustments, a physically executable sequence is exported as a .gp file. 8. Drawings

[0034] (Please attach as separate sheets) Fig. 1 - System architecture: Block diagram of modules (101)-(107) with data flow between input module, pattern database, retrieval module, synthesis module, constraint module, validation module and output module. Fig. 2 - Constraint evaluation: Flowchart of the validation process: Input parameters → Derivation of constraints (a)-(e) → Examination of the candidate sequence → Decision (pass / modify / reject) → iterative loop → Output.

Claims

(Independent - System) System for generating playable structured practice files for a string instrument, comprising: - a processor and memory associated with the processor containing instructions; - an input module (101) configured to receive user input and transform the input into a set of quantifiable parameters, including at least tempo, rhythmic subdivision, technique type, and difficulty level; - a pattern database (102) containing abstracted musical patterns, each indexed with metadata encompassing tonal, rhythmic, technique-related, and physical playability attributes; - a retrieval module (103) configured to retrieve patterns from the pattern database based on parameters derived from the input module; - a synthesis module (104) configured to combine and transform retrieved patterns into at least one candidate sequence;characterized in that the system further comprises: - a constraint module (105) configured to derive dynamic physical playability constraints as a function of the quantifiable parameters, wherein the constraints represent physical properties of the target instrument and biomechanical limits of the performer and include at least: (a) a string-specific maximum fret position derived from the physical construction of the instrument, (b) a maximum finger span as a function of the difficulty level derived from the biomechanical reach of the human hand, (c) a maximum positional displacement along the fingerboard per time interval as a function of tempo and technique type; - a validation module (106) configured to check each candidate sequence against all constraints derived from the constraint module and to reject or modify sequences that violate at least one constraint;- an output module (107) configured to encode validated sequences into an instrument-specific binary notation format that includes, for each note, at least string assignment, fret position, time value and technique annotation.; (depending on claim 1) System according to claim 1, characterized in that the constraint module (105) is further configured to perform a transition check for each pair of consecutive notes in the candidate sequence, in which the required position change is related to the available time interval, and to reject transitions whose position change per unit of time exceeds a tempo-dependent threshold. (depending on claim 1 or 2) system according to claim 1 or 2, characterized in that the constraint module (105) is further configured to limit the maximum note density per bar as a function of tempo and rhythmic subdivision, so that physically unexecutable note clusters at high tempo are excluded. (depending on one of claims 1 to 3) system according to one of claims 1 to 3, characterized in that the validation module (106) is configured to iteratively return candidate sequences to the synthesis module (104) until a sequence is generated that satisfies all constraints derived from the constraint module (105). (depending on one of claims 1 to 4) system according to one of claims 1 to 4, characterized in that the pattern database (102) contains patterns which are each indexed with physical playability metadata which include the frets and strings occupied within the pattern, the maximum finger span and the required positional displacement, and that the retrieval module (103) is configured to retrieve only patterns whose indexed playability metadata are compatible with the constraints derived from the constraint module (105). (depending on one of claims 1 to 5) system according to one of claims 1 to 5, characterized in that the input module (101) is further configured to load parameter profiles assigned to the user, which include technique weightings, preferred difficulty ranges and tempo ranges, and to derive missing input parameters from the assigned parameter profile. (depending on one of claims 1 to 6) system according to one of claims 1 to 6, characterized in that the synthesis module (104) is configured to generate multiple sections, each with a different technique type, different difficulty level and optionally different key, within a single output file, wherein the constraint module (105) derives a separate set of physical constraints for each section. (depending on one of claims 1 to 7) system according to one of claims 1 to 7, characterized in that the output module (107) encodes the validated sequence into the Guitar Pro binary format (.gp), including string assignment, fret position, note time value, tempo annotation, time signature changes and instrument-specific technique annotations. (Independent - Data carrier) Computer-readable data carrier with instructions stored on it which, when executed by a processor, cause the processor to implement the system according to any one of claims 1 to 8. (Independent - Product) Data processing device configured to generate playable structured practice files for a stringed instrument, comprising: - Means for receiving user input and transforming the input into quantifiable parameters; - Means for retrieving abstracted musical patterns from a structured database; - Means for combining retrieved patterns into a candidate sequence; characterized in that the device further comprises: - Means for deriving dynamic physical playability constraints, including string-specific fret spacings, biomechanical finger span limits, and tempo-dependent position displacement limits; - Means for validating the candidate sequence against all derived constraints; - Means for encoding validated sequences into an instrument-specific binary notation format.

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