COMPUTERIZED MUSIC NOTATION SYSTEM

Abstract: A computerized music notation system has a first keyboard (21) having pitch keys, a second keyboard (22) for entering relative rhythm codes representing the relative proportions by which the entered pitches (13) and other rhythm types (14, 15, 16, 17) divide a beat and terminator code to mark the end of each beat, and a computer (23) executing a processing program for generating output music notation in beat units based upon the pitch data and the rhythm data. The pitch and rhythm data sets are independent of each other. The computer (23) processes the pitch data assigning pitch names in the selected key of music, and the rhythm data in beat units by assigning computed fixed duration values to the rhythm types in accordance with the selected time signature. The pitch and rhythm data are combined and processed for output with other notation features, such as staff lines (10a, 10b), stems (13a), flags (13b), beams (18) and articulation marks (19, 20).

Description: COMPUTERIZED MUSIC NOTATION SYSTEM FIELD OF THE INVENTION The invention relates to a computerized music notation system in which pitch codes are entered on an instrument keyboa and rhythm codes are entered on a control keyboard as data sets independent of each other. The pitches and rhythm codes are th processed together by a computer program in order to produce integrated music data for storage, modification, translation, display, printed music notation, synthesized music or other for of output. BACKGROUND OF THE INVENTION Music notation has traditionally been written out by ha and entered in an automated system for publication as typeset o printed sheets. The manual process of handwriting, revising, and/or transcribing music notation can be very laborious for th music composer. For the muε 'c publisher, the conversion of handwritten notation into an automated typesetting or printing system requires the manual inputting of data, and only a limite capability exists for compositional modifications. The data generally must be reentered if the rhythm of the music is substantively changed. Micro computers have been applied to music composition f digital processing of music data. Such computer systems allow a composer to compose on a keyboard and to store, manipulate, and output the data as synthesized music or as printed music notatio These systems have been generally of two types, i.e. realtime coding and non-realtime coding. In realtime coding systems, mus is entered on an instrument keyboard, such as a piano-type keyboard, with exactly the timing and rhythm as it is intended to be played. The key inputs are analyzed by computer for their indicated pitches and the actual time durations and rhythms by which they are pressed on the keyboard in order to derive the proper notation. In non-realtime systems, the pitches are entere as separate data from their durations and rhythms. As an example of a realtime system, Davis et al. U.S. Patent 3,926,088 employs an organ keyboard on which an operator plays the pitch keys and a foot pedal which is pressed to indicat t e start of each measure. The pitch keys in each measure are then processed into music notation according to the time duration and rhythmical ordering in which they are pressed. Such realtime systems have the disadvantage that the music must be played through with metronomic accuracy in order for the durations and ordering of the pitches to be analyzed correctly. The necessity of entering the pitch keys exactly as they are to be played severely limits the .ability of the composer to compose or modify the music at the keyboard. Further, such systems have built-in r limitations in discriminating notes of short durations or of complex rhythms. In non-realtime systems, pitches are entered by selecting from an array of designated pitch keys, and the note durations associated with the pitches are entered separately by selecting from a prescribed set of binary fractions, i.e. halfs, quarters, eighths, sixteenths, etc., in order to define the desired music notes. Other rhythmical types, such as ties (continued notes) an rests (pauses), are entered in a similar manner as the pitches. For example, Rauchi U.S. Patent 4,307,645 and Ejiri et al. U.S. Patent 4,215,343 disclose non-realtime coding systems having keys for standard notes, ties f and rests in binary fractions. Namiki et al. U.S. Patent 4,202,235 employs note duration keys in integ multiples of l/16th intervals. Such non-realtime systems are cumbersome to use since a specific duration is assigned in a fixed relationship to each pitch key. These systems have little capability of modifying th music notation into different time signatures without reentering the data. Moreover, the same rhythm representations in some cas may be played with different actual time durations, since conventional music notation uses binary note symbols whereas mor complex rhythm structures may be desired. The assignment of a fixed binary symbol to each pitch in conventional systems would therefore result in music data that did not represent actual tim durations for a wide range of rhythms, and would limit the usefulness of the data, for example, for playing the music on a synthesizer. SUMMARY OF THE INVENTION In view of the aforementioned limitations of conventiona systems, it is a principal object of the present invention to provide a computerized system in which pitch data and relative rhythm data are entered as data sets independent of each other, and then are processed together to generate an integrated music data output. A central feature of the invention is that the rhythm data represent the relative proportions by which the pitches, rests, ties, and other rhythm types divide a basic musi interval, such as the main beat, so that their relative proportions remain specified even if the time signature of the beat is changed. It is a further object that a screen display, printed music notation and other forms of output can be generate from the pitch and rhythm data responsive to a wide range of selected compositional parameters, and can be modified or changed by computer processing without having to reenter the original data. In accordance with the invention, a computerized music notation system comprises: (a) first entry means for entering pitch data representing a series of tone pitches; (b) second entry means for entering relative rhythm data representing the relative proportions by which selected rhythm types, including the pitches as one rhythm type, divide a basic music interval, such as a beat of the music, wherein the rhythm data includes at least a first rhythm code indicating each main division of the beat by a pitch and a demarcator code delimiting each beat; (c) processing means for processing the rhythm data with the pitch data, including (1) means for assigning relative beat division values to the rhythm - codes of each beat in accordance with beat divisions indicated by the relative rhythm data, (2) means for selecting a fixed duration value assigned to each beat, (3) means for calculating fixed beat division values for the rhythm codes in each beat in accordance with the fixed duration value assigned to the beat and the relative beat division values assigned to the rhythm codes, and (4) means for linking the fixed beat division values for the rhythm codes to corresponding ones of the series of pitches; and (d) output means for providing an output of the pitches linked to their corresponding fixed beat division values. The above-described basic structure of the invention provides for the pitch data to be entered independently of the corresponding relative rhythm data, and the two sets of data are processed together to assign fixed duration values to the pitches according to a selected time signature. In the preferred implementation of the invention, the main beat of the music is the basic duration interval, i.e. the preferred system is beat oriented. In standard music notation, the time signature indicates the number of beats per measure and the note duration each beat, e.g. half-note per beat, quarter-note per beat, etc. The system according to the present invention processes the pitc data and the relative rhythm data together by assigning note duration values to the pitches calculated according to their relative proportions within a beat and the note:duration per bea The relative rhythm coding of the invention also include rhythm codes for other rhythm types, i.e. ties, rests, and dots, as well as subdivision codes for designating subdivisions of any main division of a beat by the rhythm types. The codes are selected to correspond to conventional types of rhythm notations so that entry and interpretation of the rhythm codes parallels conventional music notation for the convenience of the user. Th rhythm codes constitute a relatively small code set, yet they allow expression of music notation to a high degree of rhythmica complexity. The main division and subdivision codes permit the user to encode note durations other than conventional binary fractions, e.g. l/3rd, l/5th, l/6th l/7th notes, etc. If the user desires to have music notation translated in a different time signature, the original pitch and relative rhyt data can be retrieved from storage, and the note durations of th pitches and other rhythm types can be recomputed for the new tim signature. Since the relative rhythm codes represent the intend proportions by which the rhythm types divide each beat, the same rhythm codes can be used both to generate music notation using standard binary note symbols, and also as data to a synthesizer representing the actual durations of the notes to be played. Th ke of music can also be selected as a system parameter, and the corresponding pitch names and the proper locations and notehead styles of the notes on a musical staff are defined during processing of the pitch data in the selected key. The preferred system configuration of the invention includes an instrument keyboard for entering pitch data by pressing corresponding pitch keys, a control keyboard for entering the relative rhythm codes, as we ' ll as command codes for selecting the parameters of and operating the system, a computer for executing the program for processing the pitch and rhythm data, and associated output devices such as a display screen, a printer, a music synthesizer, and/or a data storage device. Pitch and relative rhythm data for the system can also be derived by computer processing in reverse sequence to that described above, from input obtained through digital scanning and feature recognition of original music notation. Other features of the computerized music notation system of the invention include program routines for deriving ledger lines, staff notations, stems, flags, beams, dotted notes, notehead designs, articulation marks, line, measure, beat, and note spacings, and other aspects of fully featured music notation. The invention is advantageous for a wide range of applications, e.g. composition, music synthesis, printing of music notation, computerized music archiving, and performing high speed retrieval, regeneration, and modification of music data under computer control. BRIEF " DESCRIPTION OF THE DRAWINGS The above-mentioned objects, purposes, features, and applications of the invention are described in further detail below in conjunction with the drawings, of which: Fig. 1 illustrates an example of conventional music notation; Fig. 2 is a chart depicting conventional note symbols fo pitches and other rhythm types; Fig. 3 is a schematic diagram of an overall computer system configuration including associated input and output devic and computer processing sections in accordance with the inventio Fig. 4 is a chart of a preferred set of relative rhythm codes used in the invention; Fig. 5 is a flow diagram of the Main Parsing Loop for pitch and rhythm data in the preferred notation processing progra of the invention; Fig. 6 is a flow diagram of the Beat Processing routine o the processing program for processing the pitch and rhythm data i beat units; Fig. 7 is a flow diagram of the LVIDRW routine for processing the pitch and rhythm data into an integrated music dat output form; Figs. 8(a) and 8(b) are flow diagrams of the BCODI subroutine of LVIDRW for converting the input rhythm codes into rhythm data with assigned relative beat division values; Fig. 9 is a flow diagram of the BVNLOC subroutine of LVIDRW for determining notation parameters for the output of full featured music notation; Figs. 10 and 11 are schematic diagrams of input and outpu functions for a beat of music; Fig. 12 illustrates storage and retrieval of music data t or from permanent storage in beat units; Fig. 13 illustrates regeneration of output data from permanent storage to associated output devices in beat units; Fig. 14 is a chart of some attributes of notation parameters and output data generated by the notation processing program of the invention; Figs. 15(a), 15(b), 15(c) , and 15(d) show some examples o the conversion of rhythm code sequences to output notation in the preferred system of the invention. DETAILED DESCRIPTION OF THE INVENTION In the following description, certain conventions and terminology .for music and music notation are used. These are discussed below in order to explain their intended meaning. However, it should be understood that the invention is deemed not to be limited by the conventions and terminology used within this description, but rather shall encompass the full range of potential forms and applications to which its general principles might be adapted. Referring to Fig. 1, a musical score is written with note marked on ledger lines 10, which are grouped in staffs 10a, 10b, indicating treble and bass clefs in which the music is played. The position of the notes on the lines or spaces of the staff represent the pitch of the note in the indicated octave. A fundamental key of the music ("C major" in Fig. 1) is selected to define the starting pitch of the octave scales indicated by the musical staff. The staff lines are divided horizontally into measures by vertical bars 11. Each measure or bar of music is composed of a. series of regular beats 12 which form the primary recurring rhythmic pulse of the music. For the implementation of the invention as described herein, the beat is the basic music duration interval for which music data are coded, A time signature is selected for the score to define the number of be to a bar and the notehead expression of each beat. Thus, in t example of Fig. 1, music written in 4/4 time signature has fou beats 12-1, 12-2, 12-3, 12-4, to a bar and each beat has a qua note duration. The actual time duration of each beat depends the tempo by which the music is played. The tempo is set by individual interpretation, or may be set by a timing scale in music synthesizers. - The rhythm of the music, i.e. the ordering of sound, i defined by certain conventional rhythm elements or tyρeε,-vhic include pitches 13, ties (continued pitch) 14, rests (pauses) and 16, and dots (dotted notes) 17. A dot follows a pitch not rest symbol and indicates a sustaining of one half the duratio the associated note. It can also be used as an abbreviation f several ties. Pitch notes and rests have different notations depending on their duration. In Fig. 2, the conventional note designs using binary symbols for note duration are shown, alon with the notations for ties and dotted notes. An octave on a piano keyboard has a regular progressio 7 pitch names and 12 semitones from one octave to the next. In key of C, for example, an octave progresses by pitches named C E, F, G, A, B, C. The progression of pitches of an octave dep upon the keynote pitch and the convention for the progression keys on the keyboard. Some pitches are assigned different pit names depending on the key of the music. Pitch notes are indicated in music notation by an incl oval dot which, for fractions of a whole note, have a stes 13a the left or right side. The stems may have flags 13b indicati binary note fractions, or they may have a beaa 18 joining the sterns of a group of notes in a beat. Beams can have different angles of inclination and lengths depending on the ascent or descent of the grouped notes, and may have multiple beam lines representing binary fractions to express divisions of the beat. The actual duration by which flagged or beamed notes are played depends upon the proportions by which the notes divide a beat and the note duration assigned to the beat. If the actual duration of the note is a non-binary fraction of the beat, the convention in music notation is to depict the note with the closest binary fraction representation. For example, for a quarter-note beat interval, two combined (beamed) eighth-notes indicate two pitches each played with an eighth-note duration, whereas three beamed eighth-notes (a triplet) are used to indicat three pitches each played in one-third of the quarter-note beat interval. Thus, the conventional binary representations in music notation do not necessarily correspond to the actual durations of the notes when performed. Two or more notes beamed together may have a spline indicating that they are a dublet, triplet, etc. Standard music notation also includes articulation marks, such as for emphasis 19, deemphasis 20, etc. QXS£all*,£QΘBUfc££*S2SfcSS In accordance with the invention, a preferred system configuration is shown in Fig. 3. An instrument keyboard 21, suc as a piano-type keyboard, is used to enter pitch codes corresponding to the pitch keys depressed into computer system 23 A control keyboard 22, such as a standard ASCII keyboard, is used to enter rhythm and command codes into computer system 23 as an independent data set. For ergono ic ease of use, the rhythm code may be entered by other types of input devices such as foot pedals, a speech recognition module, light pen, mouse, head movement monitor, or other type of simple coding device. The computer system 23 executes a program for music dat processing functions, of which the main part in this invention the notation data processing section 24. This section receives input pitch codes (PCODE) from instrument keyboard 21 and rhyth codes (RCODE) from command keyboard 22 or input device 22a, and processes them together in a Main Parsing Loop which generates output data -tables (NTDATA) specifying music notation characteristics for final output to a screen display 25, throug display interface 25a, and/or to a printer 26, through printer interface 26a. Permanent storage 27 is connected to computer system 23 for storage and retrieval of the notation data, and a of the original data sets PCODE and RCODE in Simple Code Form, an intermediate rhythm data set BBCODE, as described further below. Previously stored Simple Form Code or BBCODE can be retrieved from permanent storage 27 and processed with modified compositional parameters by processing section 24 into a modifie output for display or printing. The pitch and rhythm data, preferably in the intermediat BBCODE form, can also be output to a music synthesizer, through synthesizer interface 28a, for producing sound. The pitch and rhythm data can also be derived by reverse processing of notatio data provided from a digital scanner 29 used to scan an original printed or handwritten music sheet. The input from scanner 29 c be decoded by a feature recognition algorithm through recognizer 29a to extract data on notation characteristics in the same form as NTDATA, so that it is stored, processed, and/or output throug the other parts of computer system 23 and its peripheral devices Alternatively, a low level recognition algorithm can be used to extract pitch and rhythm data in the Simple Form Code or intermediate BBCODE formats. The components of the above-described system can be assembled from computer equipment which is commercially available. The basic processing functions of the notation data processing section 24, receiving pitch and rhythm code inputs and providing NTDATA output for display or printing, will now be described. The system is initialized and the desired compositional parameters, such as time signature, key of music, main beat, notation form, spacings, etc., are entered by command codes on control keyboard 22. - Once the system is initialized for composing, the user enters pitch codes by pressing keys on the instrument keyboard 21, and rhythm codes on the control keyboard 22 or ergonomic input device 22a. The two data sets are entered in non-real time r i.e. independent of each other and without regard to the actual way the final music is intended to be played. For example, the user may play the pitch keys for a beat, measure, line or several lines of music, then go back and enter the rhythm codes corresponding to those units. The user may also play the pitch keys while simultaneously entering, the rhythm codes, by key presses, foot pedal control, speech command, etc., in or near realtime. If the rhythm codes are a series of recurring codes, they can be entered automatically by a macro command. The flexibility of entering rhythm codes as an independent data set from the pitch codes is an important advantage of the invention. As the two streams of pitch and rhythm codes are entered, they are temporarily stored in buffers and parsed in Simple Form Code through the Main Parsing Loop shown in Fig. 5. In the described implementation of the invention, the notation processin section 24 processes pitch and rhythm data in beat units, i.e. according to the main beat specified by the selected time signature. The pitch and rhythm codes are thus processed by the beat processing loop BTPROC shown in Fig. 6, and by the beat data generating routines LVIDRW, BCODI, BVNLOC, and BHRHY, and display output routine LV2DRW, shown in Figs. 7-9, from intermediate BBCODE into output tables NTDATA which completely specify the beat units of music notation for output on the display screen 25 or the printer 26. The input and output routines for the beat data are shown in Figs. 10 and 11. Previously stored data can be retrieved by the routine shown in Fig. 12 and regenerated as shown in Fig. 13 for a modified output using new compositional parameters or for mass output, such as for high speed printing. A central feature of the invention is t ' he use of rhythm codes which represent the relative proportions of rhythm types within a defined music interval, such as a beat. The fundamental music interval in Western music is the main beat. The use of relative proportion values for the rhythm elements allows their representation within a beat to remain unchanged even if the time signature of the beat or tempo of the music is changed. Thus, the notation can be readily changed for a different time signature, or one or both of the pitch and rhythm code sequences can be retrieved and modified, without having to reenter all of the original data. The preferred set of rhythm codes of the invention are selected to have a one-to-one correspondence to the rhythm types recognized in conventional music notation, for the convenience of the user in entering and interpreting the rhythm code sequences. The preferred rhythm codes thus comprise a set of main division codes, representing each rhythm type, i.e. pitch, tie, rest, or dot, which may divide. beat, subdivision codes for each rhythm type subdivision of a main division, a beat deraarcator code, and beat multiple codes for a rhythm element occupying a multiple beat. Each beat is processed with all rhythm elements related to either main divisions, subdivisions, or multiples of the beat interval. The pitch codes entered as an independent data set are? related in correspondence to the rhythm codes for pitches, and the integrated data can then be further processed to provide a display or printed output of fully featured music notation. The preferred set of rhythm codes is shown with representational characters in Fig. 4. Each pitch entered on the instrument keyboard is associated with the pitch rhythm code "N" if it is a main division of a beat. A pitch subdivision of a main division is denoted by "n". Similarly, rests are denoted by "R" if they are main divisions of a beat unit, or by "r" if they are a subdivision of a main division. Ties are indicated by "T" and "t" and dots by "D" and "d" for corresponding main divisions and subdivisions. By convention, a beat interval cannot begin with a dot or with any subdivision. The end of a beat interval is denoted with a terminator code such as "/". For example, if a beat is composed of two pitches of equal duration, the rhythm codes "N, N, /" are keyed in. If a beat is composed of two pitches which are the onset of two equal intervals, and the first interval includes another pitch which subdivides the first interval, then the codes "N, n, N, /" are k ' eyed in. Examples of other rhythm code sequences are shown in Figs. 15(a)-15(g), together with their resultant data table and music notation. By using a stream of codes to represent each rhythm element in the beat intervals, the relative duration values of th elements become implicit in their order and number, and the absolute duration of the elements can be derived for any specifie beat duration (time signature) . The use _ of subdivision codes provides a second order level of beat complexity which is commensurate with the limits of human performance of music. Higher order levels of relative rhythm coding may of course be used. According to the principles of the invention, it is apparent that other rhythm code sets or more specialized rhythm types may instead be used. For example, beat division codes may indicate the proportions of beat divisions by numerical weights, the rhythm types may be numerically coded, independently entered, or entered with the pitch codes, a beat commencing code instead of terminator code may be used, or the basic duration interval may be a measure of music rather than a beat. Such variations are nevertheless encompassed within the principles of relative rhythm coding as disclosed herein. Since each beat is delimited by a terminator code, the rhythm codes can be input without any required continuity, as can the pitch codes. The notation processing program parses the two independent data streams through the Main Parsing Loop and processes a beat output whenever sufficient pitch data and rhythm data followed by a terminator code are input. The terminator code is used herein as a beat delimiter, but a beat initializer could instead be used. The relative rhythm coding also includes an autoterminator code "A" for providing a recurring series of rhythm codes followed by a terminator code automatically when the music being composed has a regular number of pitches in equal main divisions of each beat. This allows the rhythm coding to be handled automatically by a single keystroke for convenience of data entry for many standard rhythms. The main rhythmic types, i.e. pitches, rests, ties, or dots, represent the conventional musical rhythmic notations. Depending on the time signature and the main beat duration, any combination of these rhythmic types may be used in a beat, and the resultant notation for a beat may be expressed with the notes joined together by horizontal beams and tuplet indicators. If the time signature is changed, the relative proportions of the rhythm elements are nevertheless preserved over the current fraction or multiple of the original main beat, and the resulting notation may be expressed differently, i.e. with multiple or no horizontal beams or different notehead designs. The relative rhythm coding includes auxiliary codes for multiples of a beat unit, e.g. when a rhythm element has a duration of multiple beats. In Fig. 4, three integer multiple codes are shown. Also, a particular series of rhythm codes which is used frequently may be input through a single keystroke by use of a macro key, which provides a stored stream of characters as input codes. The relative rhythm coding of the invention is selected to be a small, manageable set, but it may of course may be expanded if more complex rhythm coding functions are desired. A small set of rhythm codes allows the rhythm data to be input rapidly and with a minimum of interruption so that the user can simultaneously input the pitch codes from the instrument keyboard 21 if so desired. In the system shown in Fig. 3, the rhythm coding is entered by any selected alphanumeric keys on the control keyboard 22, but it may instead be entered through other, more ergonometric input devices such as foot pedals, a speech recognition unit, a monitor for head movements, or pointing or contacting devices su as a light pen, touch tablet, mouse, etc. The Main Parsing Loop for pitch and rhythm codes in beat units is shown in Fig. 5. Block 31 indicates the major system initialization steps, such as interfacing the various system components for the notation processing mode. KEYCMD at block 31 indicates the initialization steps for user parameter selections and establishing the internal parsing program to receive and process pitch and rhythm codes as they are input from the instrument keyboard 21 and control keyboard 22, and to display t output notation on staff lines set up on the CRT display 25 for visual confirmation to the user. Program control then enters INLOOP at block 31b, which commences with a test whether a macro sequence of codes is being stored or sent. If no macro sequence is in effect, the parsing program polls the control (ASCII) keyboard for a command or rhythm code (RCODE) keypress, at block 32, and the instrument keyboard for a pitch code (PCODE) keypress at block 33. Simultaneous pressing of more than one pitch key ( chord) is treated as one pitch key event for purposes of the description herein. The program proceeds to block 34 which sends the PCODE to block 35 where the pitch is identified and displayed on the staff lines as it is entered (without rhythm information) for visual confirmation. Pitch processing at this stage includes determination of all attributes of pitch information needed for proper musical notation, e.g. pitch name, accidentals (sharp or flat), location on the staff lines, a chord, etc. The processed pitch data are then stored in a temporary pitch buffer ODTPIT. A command keycode or the RCODE is branched from block 34 to block 36, where it is interpreted, and then to PROCKEYS at block 36a. The PROCKEYS routine executes an indicated command, or branches the RCODE to block 36b where it is converted to Simple Form Code (binary number) and stored in a temporary rhythm buffer ODTRHY. The parsing program then goes to block 37 at the end of the parsing loop where it returns to INLOOP. At block 36c, a check BTDEST is made whether sufficient rhythm and pitch codes have been received for a beat and whether a beat termination code is received. If so, the program branches at block 36d to execute the BTPROC routine at block 38, which is the main routine for generating the complete output notation for each beat. When an output beat is generated, it is displayed on the staff lines (the pitch-only display is erased) , then the beat counters are incremented and a vertical bar line is drawn if a measure of music has been completed. The parsing loop then receives the next input by returning to INLOOP. Referring to Fig, 6, the main beat processing routine BTPROC commences by clearing an output data table NTDATA for the beat, at block 38a, fetching the current beat pitch record from ODTPIT at block 38b, and fetching the current beat rhythm record from ODTRHY at block 38c. The program enters LV1CALL and calls the routine LVIDRW, described further below, for processing the pitch and rhythm data into its final output form, which is then stored as output data and displayed as a completed beat on the CR display. The program then moves the beat cursor to the current beat space on the staff lines of the display, at block 38d, and increments the beat counter, checks the space remaining on the current line, and check3 the beat count for a completed measur at block 38e. The program then exits BTPROC and returns to IN in the Main Parsing Loop for the next beat. The routine LVIDRW, shown in Fig. 7, commences by chec at block 41 whether the code for a multiple beat interval (bea multiplier code in Fig. 4) is present. If so, the routine HBT.EXPAND is called at block 42 to expand a beat interval code into -<%wo or more beat interval codes in a form compatible with subsequent rhythm data processing. At block 43, the routine SETPIT is called to process the pitch data further to determin the stem direction (upward or downward) and any flag or beam attributes for the output notation. At blocks 44 and 45, a ch of the stem direction is made and the pitch data is modified s that the specification of notes corresponds to the proper stem direction. The program then proceeds to block 46 where the furthe routine BCODI is called to convert the rhythm data for the bea from Simple Form Code to the intermediate form BBCODE, BBCODB a conversion of the rhythm codes from a simple number to a form where the relative proportion of each rhythm code element within a beat is expressed. At blocks 47 and 48, a check is m whether the current beat is a multiple of the main beat interv and, if so, the beat width and end of beat notation are appropriately modified. At block 49, the ledger line data for current beat is initialized. At block 50, a check is made whe the current beat is the end of a series of beats having simple notation which can be compressed into a smaller width for one measure on a line of output notation, referred to herein * as a "dynamic beat" . If so, the beat widths are recalculated and modified, at block 51, and a compressed notation for the -measure is substituted for the constituent beats. At block 52, the pitch and rhythm data is now sufficientl specified so that processing of them together can take place. At BVNCALL 53, the subroutine BVNLOC is called to merge the pitch an rhythm data together, as explained further below. The output of BVNLOC is integrated information on all required attributes of th note(s) occupying the current beat (at block 54) . In preparation for final processing for an output display of notation, the integrated information is input at BRMCALL 55 to the subroutine BHRHY which calculates all of the stem, beam, and beat dimensions corresponding to the specified note(s) in accordance with standar music notation. The program then proceeds to LV2CALL 56 where th output graphics display subroutine LV2DRW is called. This completes the processing and output display of one beat of music, and control then returns to the Main Parsing Loop for the next beat. Bsa SutacQutiαes The subroutine BCODI for converting the rhythm codes for beat in single byte (Simple) form to the intermediate BBCODE is shown iri Figs. 8(a) and 8(b). Simple Form Code for the rhythm codes are input at block 65. The BCODI pointers are initialized at block 66, and the program enters MAINLOOP 67 with a test for termination. One main beat interval at a time is processed through MAINLOOP. If there are multiple main beats in the curre beat interval being processed, MAINLOOP is reentered until a termination for the complete sequence is detected, as shown at block 67. Processing for each main beat interval begins with initialization of the counters for main-divisions and subdivisi in the beat, at block 63, The rhythm codes are then parsed through the loop 70, 71, 72, 73, 75, 76, 79, until a total coun MDIV, at block 74, of main division codes has been counted. MD represents the number of main division intervals into which the beat is divided. At blocks 77 and 78, a test is made whether t number of main division codes is two or three, in order to set a BREAKFLG which results in output beamed notation having breaks i the beaming if any subdivisions of a main division are present, according to music notation convention. The program proceeds to SDBLOOP 80a, 81, 82, 83, 84, whe each main division is checked in turn for subdivisions. When th count of subdivision(s) SDIV(i) for the current subdivision is obtained at block 80, the program proceeds to block 85, in Fig. 8(b), where the product of MDIV and SDIV(i) is obtained. This product represents the relative fraction of the beat occupied by each of the rhythm elements expressed by the current main divisi code and following subdivision code(s) . In the loop 86-98, the program parses through each of these fractional rhythm elements and loads the BBCODE representing their fractional proportion of the beat. When the current main division has been processed, th program proceeds with a test whether the current beat is completed, at block 100. If yes, a terminator in BBCODE is inserted, at block 99, and control returns to MAINLOOP at block 102 for conversion of the next main .beat interval. If no, a che is made for a BREAKFLG at blocks 101, 103, in order to insert a BREAKSYM code for beam breaking in the- final output (mentioned above) , and control then returns to SDBLOOP at block 104. Referring to Figs. 15(a)-15(d) , some examples are shown rhythm codes converted to the BBCODE -form. In particular, Fig. 15(d) shows one which includes main division, subdivision, tie and rest codes converted into BBCODE. BBCODE is represented by an integer representing the rhythm element's fractional space in the beat and a character representing the type of rhythm element. BBCODE thus expresses the relative fractions and types of rhythmic elements as a highly compressed data set. The BVNLOC subroutine shown in Fig. 9 fills in the output table NTDATA with further speci ication of the various notational and spatial attributes of the output notation corresponding to the pitch and rhythm data in accordance with standard music notation conventions. At block 120, pointers to NTDATA are initialized. A test is made at block 121 if the previous beat is tied to the current beat. If so, then a tie marker is stored in the NTDATA table. MAINLOOP 122 is the entry to a parsing procedure for determining the notational attributes of tied or dotted rhythm elements. Beginning at block 128a, a test is made at block 129 for a note or tie. If yes, a test is made at block 129a whether the next adjacent elements are ties or dots. If they are not, a single note is detected (block 130), and control goes to blocks 139a and 140 where the subroutine BTDIV is called for computing the attributes of single note, rest or tie. - If there are adjacent ties or dots to a note or tie, their number and beat fraction are determined at blocks 131, 132. BTDIV is then called at block 133 to determine the note duration (based on the time signature and relative beat fraction) and the appropriate notational attributes, i.e. type of notehead, stem flags, number of beams, placement of dots, etc., and STORE is called to load all generated attribute information together with the associated pitch data to the output table NTDATA. Tests are made at block 141 for beam values," stem flags, dots, and other data to be stored in CONTINDE 142 and returns to MAINLOOP 122. If the test at block 129 is negative, a test is made at block 134 whether the current rhythmic type is a rest, and if so, blocks 134a, 135, process for a single rest or for a tied or dotted rest, similar to the procedure described above. If the test at block 134 is negative, a subtest for a BREAKSYM (beam break) code is made at blocks 136, 137, and for a multiple beat a block 138. If a multiple beat is present, the subroutine FRACTAD is called to determine the fractions of the beat allocated to the current rhythmic notation. Control then returns to MAINLOOP 122. If the list of rhythmic types for the beat is ended, the program exits at block 123, then tests for beams at block 124. If no beams are present, then the default " beam values are suppressed. After exiting BVNLOC, the further subroutine BMRHY is called to provide further notational attribute information in which the key coordinates, contours and endpoints of the notation elements are specified. The subroutine LV2DRW is then called to generate the complete contour and mapping information for output to the display screen. An example of some of the various notational attributes processed into NTDATA in the processing program is shown in Fig. 14. The notation processing program described above is beat oriented in that it processes input pitch and rhythm data in beat units and outputs a completed beat of music data. As shown in Fig. 3, the notation data processing 24 is the center of input/output flows connecting the input keyboards and devices 21, 22, 22a, the permanent storage 27, and screen display 25. An I/O program loop is shown in Figs. 10 and 11. Beginning a -INLOOP, the program determines whether input data is obtained from a keyboard, the screen display, permanent storage, or a macro buffer. If from a keyboard, input is provided by the keypresses, or if from the screen display, then it is fetched via the screen matrix. Input from permanent storage (hard disk) is fetched via beat matrix which stores all the addresses for each beat of the entire music for random access and global editing. Regardless of source, -input is provided for one beat at a time and processed through the notation processing program to generate one beat of music data output. The beat output in Fig. 11 may be sent to the screen matrix, a macro buffer, and/or hard disk matrix. Data processed in the notation processing program may be stored on the hard disk as Simple Form Code for the streams of keypresses from the keyboards, intermediate BBCODE representing the rhythmic proportions and types in compressed form and the pitch names, and/or the output table NTDATA for generating a complete display of beat notation. In the I/O program, if the SODNDFLG is set at block 240, then the output data may provided in the compressed (BBCODE) format suitable for realtime performance. This format may be used, for example, to provide music data to the synthesize interface 28a, in Fig. 3, for synthesizer performance. For certain high speed or high volume applications, such as printing hard copy, searching, or mass storage, the music data for an entire section or score of music may be held in a cache memory an output in a continuous stream. A flowchart for music data storage and retrievel is shown in Fig. 12. In the preferred beat oriented system of the invention, a beat received from the notation processing program i assigned a key address which is stored in BTMATRIX. Searching an retrieval of music is obtained by requesting the key addresses o the music section of interest, and the stored data is loaded in buffer area where it can be used in the music program or another connected device or interface. Beat matrix manipulations can be performed to relocate sections of music or to copy, or alter dat in some way. This facilitates insertions of new material, deletions, or copying, and allows high level manipulation of lar data sets. : In Fig. " 13, a process for regenerating stored music data is shown. Music data retrieved from permanent storage 27 is hel in a buffer 27a from which data is sent in beat units. The beat data may be stored in Simple Form Code, BBCODE, and NTDATA. Simple Form Code can be entered in the notation processing progr at the entry point to the BTPROC routine, from which it is regenerated into NTDATA and displayed on the screen. Modifications or new compositional parameters can be specified through keyboards 21, 22, in an editing mode, and the modified beat can be d splayed and stored. NTDATA may instead be i' regenerated from BBCODE by a macro command providing the input i the program sequence to BVNCALL, or retrieved data in NTDATA for may be provided to the display interface 25a. The compressed BBCODE format is suitable for performance of the music in realti through the synthesizer interface 28a. The notation processing program can also have other • program sections for entering other notational features on the score in accordance with the full features of standard music notation. Articulation marks may be entered by selection from a list of icons or marks displayed on the screen using function ke on the control keyboard or other computer input device, such as a pointer, touch screen, or mouse. The desired mark is positioned in the proper score area by program control or by movement of a cursor (pointer) to a particular note, beat interval, measure, or position on the staff lines. The program for entering articulation marks includes a function for controlling the movement of the cursor so that it jumps by incremental note, beat, or bar positions for ease of use. Stored pitch and rhythm codes, as well as the output NTDATA tables, can be retrieved and modified for notation in a different key of music and/or time signature. The pitch and rhythm codes can be independently modified, for example, to produce a stored melody with a different rhythm, or a different melody with the stored rhythm, or some combination of both. Music analysis tools can be applied to analyze melody, harmony, chord progression, rhythm, and other sub-attributes of the full music notation interactively via the display screen, keyboards, or synthesizer. The flexible format of the relative rhythm coding O the invention allows music of any complexity to be i easily ^and rapidly input to the system for printing, modification, or display. The computer system may be interfaced with a printer of typesetting quality for sheet music production. The interface may include routines for compressing data, producing special fonts or marks, etc. The computerized notation system can be advantageously applied to parts extraction from or to an instrumental work or larger symphonic score. The parts of a symphonic score for different instruments are often printed with different measure and line spacings and notational formats and attributes. The relative proportions of rhythm elements represented by the relative rhythm coding facilitates the recalculation of notational formats. With the editing and modification capability of the system disclosed herein, the several instrument parts can be readily extracted a printed by data file manipulations. The invention has important advantages over conventiona music notation systems. Since the pitch codes are independent from the rhythm codes, the code input need not be played in realtime and less musically skilled persons can operate the system. This increases the utility of the system and allows savings of labor cost in high-volume music notation processing. The expanded capability of transposing the pitch and rhythm cod into another key or time signature makes possible a wide range automated music publishing functions. The intermediate BBCODE format is a compressed data set which can be readily adapted as an input to conventional synthesizers. The problem of conventional binary notation conflicting with non-binary time durations in performance, particularly with synthesizers, is obviated since BBCODE preser the actual relative proportions within a beat, while NTDATA is usable to generate notation according to music convention. Also digital scanning and feature extraction systems can be used to provide notational input to the present system from printed or handwritten original sheets. The compressed data set BBCODE can be relatively easily derived through feature extraction, and the notation processing program can be used to regenerate the full notational output tables (NTDATA) for display, permanent storage editing or modification. Although a preferred implementation of the invention has been described above, it should be understood that many variatio and modifications are possible within the disclosed principles o this invention. The rhythm codes might be modified to include other rhythm types or other ' relative division rr,arkers. For example. Instead of main division and subdivision markers, numer values may be assigned to each rhythm element representing their relative proportions within the beat. The basic interval may be full measure of music instead of a beat. The notation processin program may be simplified, and the beat processing routines may implemented by ROM addressing or tree-structure decoding of rhyt code sequences rather than program operation. Other types of be processing algorithms will occur to one skilled in this field given the disclosure herein. Further, other types of peripheral data entry, storage, output, and associated musical devices may connected to the disclosed system. It is intended that the systems described herein and all such variations and modificatio be included within the scope of the invention, as defined in the following claims. i -1

Claims: I CLAIM: 1. A computerized music notation system comprising: (a) a first input for entering pitch data representing a series of selected pitches; (b) a second input for entering rhythm code data representing the relative proportions by which each of the pitch data divide a basic music interval, wherein sai ^ rhythm code data includes at least a main division code representing each main division of a basic music interval by the pitch data, and a demarcation code for delimiting each basic music interval; (c) a third input for entering a fixed duration value assigned to each basic music interval; (d) a computer connected to said first and second inputs for linking the rhythm code data with the corresponding pitch data, wherein said computer has a program for calculating the respective fixed duration values of each of the pitch data within each basic music interval, based upon the relative proportions by which the corresponding rhythm code data representing the pitch data divide each basic music interval, as delimited by each demarcation code, and taking into account the fixed duration value assigned to each basic music interval entered in said third input; and (e) an output for providing music notation based upon said pitch data assigned their respective fixed duration values in the basic music intervals by said computer. 2. A computerized music notation system according to Claim 1, wherein said basic music interval is a beat unit of music, said fixed duration value assigned to the beat units is a selected time signature of the music, and said demarcation code is a terminator code representing the end of each beat unit. 3. A computerized music notation system according to Claim 1, wherein said second input provides rhythm code data including a main division code for rests as another rhythm type, representing the relative proportion by which a rest element divides a basic music interval in which it is designated to occur. 4. A computerized music notation system according to Claim 1, wherein said second input provides rhythm code data including a main division code for ties as another rhythm type, representing the relative proportion by which a tie element divides a basic music interval in which it is designated to occur. 5. A-computerized music notation system according to Claim 1, wherein said second input provides rhythm code data including a main division code for dots as another rhythm type, representing the relative proportion by which a dot element divides a basic music interval in which it is designated to occur, 6. A computerized music notation system according to Claim 1, wherein said second input provides relative rhythm code data including a pitch subdivision code representing a relative subdivision by a pitch of a main division of a basic music interval, 7. A computerized music notation system according to Claim 1, wherein said second input provides relative rhythm code data including " pitch, rest, tie, and dot subdivision codes representing a relative subdivision by a pitch, rest, tie and dot element, respectively, of a main division of a basic music interval. 8. A computerized music notation " system according to Claim 1, wherein each main division code is a marker for a proportional main division of a basic music interval, and said computer includes a program section for counting the number of main division rhythm codes entered for each basic music interval and calculating a fixed duration value to be assigned to each main division element based upon the fixed duration value assigned to the basic music interval divided by the number of main division codes. 9. A computerized music notation system according to Claim 8, wherein said computer includes a second program section for counting the number of subdivision codes entered within a main division and calculating a fixed duration value to be assigned to each subdivision element based upon the fixed duration value assigned to the basic music interval divided by the product of said main division number and said subdivision number. 10. A computerized music notation system according to Claim 1, wherein said third input is used to enter a fundamental key of music for the pitche data, and said computer includes a further program section for assigning proper names to the pitch data in accordance with the selected fundamental key of music, and an output program section for specifying the coordinate locations and designs of the corresponding notation elements. 11. A computerized music notation system according to Claim 10, wherein said output program section assembles data specifying said notation elements on output tables, and includes a program subsection for specifying other selected attributes of said notation elements. 12. A computerized music notation system according to Claim 2, wherein said third input provides an autoterminator code for automatically entering a predetermined number of rhythm codes for the pitch data in each beat unit and a de arcator code delimiting each beat unit. 13. A computerized music notation system according to Claim 1, wherein said output is a display screen. 14. A computerized music notation system according to Claim 1, wherein said output is a graphics printer. 15. A computerized music notation system according to Claim 1, wherein said output is a music synthesizer for generating synthesized sound. 16. A computerized music notation system, according to Claim 1, wherein said output is a data storage device. 17. A computerized music notation system according to Claim 1, wherein said first input is an instrumental keyboard. 18. A computerized music notation system according to Claim 1, wherein said second and third inputs are keys on a control keyboard. 19. A computerized music notation system according to Claim 1, wherein said second input is an ergonometric coding device which is acutated by a physical action of the user other than finger keypressing. 20. A computerized music notation system according to Claim 1, wherein said first and second inputs are provided by an optical scanner device for scanning an original sheet of music notation and providing an input of pitch data and rhythm code data based thereon.

Inventors: LUI PHILIP Y F, LUI, PHILIP, Y., F.
Applicants: LUI PHILIP Y F, LUI, PHILIP, Y., F.
Application year: 1988
Main classification: G09B15
IPC codes: G09B15, G10G3