Musical notation system

Background of the Invention

The present invention is directed towards musical software, and, more particularly, towards a system that integrates musical notation technology with a unique performance generation code and synthesizer to provide realistic playback of musical scores.

Musical notation (the written expression of music) is a nearly universal language that has developed over several centuries, which encodes the pitches, rhythms, harmonies, tone colors, articulation and other musical attributes of a designated group of instruments into a score, or master plan for a performance. Musical notation arose as a means of preserving and disseminating music in a more exact and permanent way than through memory alone. In fact, the present-day knowledge of early music is entirely based on examples of written notation that have been preserved.

Western musical notation as it is known today had its beginnings in the ninth century, with the neumatic notation of the plainchant melodies. Neumes were small dots and squiggles probably derived from the accent marks of the Latin language. They acted as memory aids, suggesting changes of pitch within a melody. Guido d'Arezzo, in the 11^th century, introduced the concept of a staff having lines and spaces representing distinct pitches identified by letter names. This enabled pitch to be more accurately represented.

Rhythmic notation was first introduced in the 13^th century, through the application of rhythmic modes to notated melodies. Franco of Cologne, in the 13^th century, introduced the modem way of encoding the rhythmic value of a note or rest into the notation character itself. Rhythmic subdivision into groups other than two or three was introduced by Petrus de Cruce at about the same time.

The modem practice of using open note heads along with solid black note heads was introduced in the 15^th century, as a way of protecting paper (the new replacement for parchment) from too much ink. Clefs and signatures were in use by the 16^th century. Score notation (rather than individual parts) became common by the latter part of the 16^th century, as did the five-line staff. Ties, slurs, and bar lines were also introduced in the 16^th century.

The rise of instrumental music in the 17^th century brought with it further refinements in notation. Note heads became rounder, and various indications were introduced to delineate tempo, accent, dynamics, performance techniques (trills, turns, etc.) and other expressive aspects of the music.

During the 18^th and 19^th centuries, music moved out of the church and court, and into a broader public arena, in the form of orchestra concerts, theater, opera, ballet and chamber music. Instrumental ensembles grew larger and more complex, and the separation between composer and performer increased. As a result, musical notation became more and more refined. By the 20^th century, musical notation had become a highly sophisticated, standardized language for specifying exact requirements for performance.

The advent of radio and recording technology in the early 20^th century brought about new means of disseminating music. Although some of the original technology such as the tape recorder and the long-playing record are considered "low-fi" by today's standards, they brought music to a wider audience than ever before.

In the mid-1980's, the music notation, music publishing, and pro-audio industry began to undergo significant and fundamental change. Since then, technological advances in both computer hardware and software enabled the development of several software products designed to automate digital music production.

For example, the continual improvement in computer speed, memory size and storage size, as well as the availability of high-quality sound cards, has resulted in the development of software synthesizers. Today, both FM and sampling synthesizers are generally available in software form. Another example is the evolution of emulation of acoustical instruments. Using the most advanced instruments and materials on the market today, such as digital sampling synthesizers, high-fidelity multi-track mixing and recording techniques, and expensively recorded sound samples, it is possible to emulate the sound and effect of a large ensemble playing complex music, (such as orchestral works) to an amazing degree. Such emulation, however, is restricted by a number of MIDI-imposed limitations.

Musical Instrument Digital Interface (MIDI) is an elaborate system of control, which is capable of specifying most of the important parameters of live musical performance. Digital performance generators, which employ recorded sounds referred to as "samples" of live musical instruments under MIDI control, are theoretically capable of duplicating the effect of live performance.

Effective use of MIDI has mostly been in the form of sequencers, which are computer programs that can record and playback the digital controls generated by live performance on a digital instrument. By sending the same controls back to the digital instrument, the original performance can be duplicated. Sequencers allow several "tracks" of such information to be individually recorded, synchronized, and otherwise edited, and then played back as a multi-track performance. Because keyboard synthesizers play only one "instrument" at a time, such multi-track recording is necessary when using MIDI code to generate a complex, multi-layered ensemble of music.

While it is theoretically possible to create digital performances that mimic live acoustic performances by using a sequencer in conjunction with a sophisticated sample-based digital performance generator, there are a number of problems that limit its use in this way.

First, the instrument most commonly employed to generate such performances is a MIDI keyboard. Similar to other keyboard instruments, a MIDI keyboard is limited in its ability to control the overall shapes, effects, and nuances of a musical sound because it acts primarily as a trigger to initiate the sound. For example, a keyboard cannot easily achieve the legato effect of pitch changes without "re-attack" to the sound. Even more difficult to achieve is a sustained crescendo or diminuendo within individual sounds. By contrast, orchestral wind and string instruments maintain control over the sound throughout its duration, allowing for expressive internal dynamic and timbre changes, none of which are easily achieved with a keyboard performance. Second, the fact that each instrument part must be recorded as a separate track complicates the problem of moment-to-moment dynamic balance among the various instruments when played back together, particularly as orchestral textures change. Thus, it is difficult to record a series of individual tracks in such a way that they will synchronize properly with each other. Sequencers do allow for tracks to be aligned through a process called quantization, but quantization removes any expressive tempo nuances from the tracks. In addition, techniques for editing dynamic change, dynamic balance, legato/staccato articulation, and tempo nuance that are available in most sequencers are clumsy and tedious, and do not easily permit subtle shaping of the music.

Further, there is no standard for sounds that is consistent from one performance generator to another. The general MIDI standard does provide a protocol list of names of sounds, but the list is inadequate for serious orchestral emulation, and, in any case, is only a list of names. The sounds themselves can vary widely, both in timbre and dynamics, among MIDI instruments. Finally, general MIDI makes it difficult to emulate a performance by an ensemble of over sixteen instruments, such as a symphony orchestra, except through the use of multiple synthesizers and additional equipment, because of the following limitations: <ul id="ul0001" list-style="bullet"><li>MIDI code supports a maximum of sixteen channels. This enables discreet control of only sixteen different instruments (or instrument/sound groups) per synthesizer. To access more than sixteen channels at a time, the prior art systems using MIDI require the use of more than one hardware synthesizer, and a MIDI interface that supports multiple MIDI outputs. MIDI code does not support the loading of an instrument sound file without immediately connecting it to a channel. This requires that all sounds to be used in a single performance be loaded into the synthesizer(s) prior to a performance.</li><li>In software synthesizers, many instrument sounds may be loaded and available for potential use in combinations of up to sixteen at a time, but MIDI code does not support dynamic discarding and replacement of instrument sounds as needed. This also causes undue memory overhead.</li><li>MIDI code does not support the application of a modification to the attack or decay portion of a sample (i.e., the start or end) without altering the original, stored sample. The prior art systems using MIDI require the creation of a new sample with the attack or decay envelope built-in, and then the retrieval of the entire sample in order to achieve the desired effect.</li><li>MIDI code allows a maximum of 127, scaled volume settings, which, at lower volume levels, often results in a "bumpy" volume change, rather than the desired, smooth volume change.</li><li>MIDI code supports pitch bend only by channel, and not on a note-by-note basis. Any algorithmic pitch bends cannot be implemented via MIDI, but must be set up as a patch parameter in the synthesizer. The prior art systems using MIDI also include a pitch wheel which bends the pitch in real time, based on movements of the wheel by the user.</li><li>MIDI code supports panning and pedal commands only by channel, and not on a note-by-note basis.</li></ul>

Furthermore several music notation systems are discussed in C. Boehm et al: "Music tagging type definitions, systems for music representation and retrieval", Euromicro Conference, September 5-7, 2000, A. Belkin: "Macintosh notation software: present and future", 1994, and C. Grande et al: "The development of the Notation interchange File Fonnat", 1996. From WO-A-0101296 a system for a compact representation of interactive data and transmitting the data via a computer network is known. This system is based on the separation of the data into graphical and multimedia data sections.

In view of the forgoing, consumers desiring to produce high-quality digital audio performances of music scores must still invest in expensive equipment and then grapple with problems of interfacing the separate products. Because this integration results in different combinations of notation software, sequencers, sample libraries, software and hardware synthesizers, there is no standardization that ensures that the generation of digital performances from one workstation to another will be identical. Prior art programs that derive music performances from notation send performance data in the form of MIDI commands to either an external MIDI synthesizer or to a general MIDI sound card on the current computer workstation, with the result that no standardization of output can be guaranteed. For this reason, people who desire to share a digital musical performance with someone in another location must create and send a recording.

Sending a digital sound recording over the Internet leads to another problem because transmission of music performance files are notoriously large. There is nothing in the prior art to support the transmission of a small-footprint performance file that generates a high-quality, identical audio from music notation data alone. There is no mechanism to provide realistic digital music performances of complex, multi-layered music through a single personal computer, with automatic interpretation of the nuances expressed in music notation, at a single instrument level.

Accordingly, there is a need in the art for a music performance system based on the universally understood system of music notation, that is not bound by MIDI code limitations, so that it can provide realistic playback of scores on a note-to-note level while allowing the operator to focus on music creation, not sound editing. There is a further need in the art for a musical performance system that incorporates specialized synthesizer functions to respond to control demands outside of the MIDI code limitations and provides specialized editing functions to enable the operator to manipulate those controls. Additionally, there is a need in the art to provide all of these functions in a single software application that eliminates the need for multiple external hardware components.

Brief Summary of the Present Invention

The present invention provides a system for creating and performing a musical score including a user interface that enables a user to enter and display the musical score, a database that stores a data structure which supports graphical symbols for musical characters in the musical score and performance generation data that is derived from the graphical symbols, a musical font that includes a numbering system that corresponds to the musical characters, a compiler that generates the performance generation data from the database, a performance generator that reads the performance generation data from the compiler and synchronizes the performance of the musical score, and a synthesizer that responds to commands from the performance generator and creates data for acoustical playback of the musical score that is output to a sound generation device, such as a sound card. The synthesizer generates the data for acoustical playback from a library of digital sound samples.

The present invention further provides software for generating and playing musical notation. The software is configured to instruct a computer to enable a user to enter the musical score into an interface that displays the musical score, store in a database a data structure which supports graphical symbols for musical characters in the musical score and performance generation data that is derived from the graphical symbols, generate performance generation data from data in the database, read the performance generation data from the compiler and synchronize the performance of the musical score with the interface, create data for acoustical playback of the musical score from a library of digital sound samples, and output the data for acoustical playback to a sound generation device.

Detailed Description of the Invention

The present invention provides a system that integrates music notation technology with a unique performance generation code and a synthesizer pre-loaded with musical instrument files to provide realistic playback of music scores. The invention integrates these features into a single software application that until now has been achieved only through the use of separate synthesizers, mixers, and other equipment. The present invention automates performance generation so that it is unnecessary for the operator to be an expert on using multiple pieces of equipment. Thus, the present invention requires that the operator simply have a working knowledge of computers and music notation.

The software and system of the present invention comprises six general components: a musical entry interface for creating and displaying musical score files (the "editor"), a data structure optimized for encoding musical graphic and performance data (the "database"), a music font optimized for both graphic representation and music performance encoding (the "font"), a set of routines that generate performance code data from data in the database (the "compiler"), a performance generator that reads the performance code data and synchronizes the on screen display of the performance with the sound ("performance generator"), and a software synthesizer (the "synthesizer").

Editor

Referring now to the editor, this component of the software is an intuitive user interface for creating and displaying a musical score. A musical score is organized into pages, systems, staffs and bars (measures). The editor of the present invention follows the same logical organization except that the score consists of only one continuous system, which may be formatted into separate systems and pages as desired prior to printing.

The editor vertically organizes a score into staff areas and staff degrees. A staff area is a vertical unit which normally includes a musical staff of one or more musical lines. A staff degree is the particular line or space on a staff where a note or other musical character may be placed. The editor's horizontal organization is in terms of bars and columns. A bar is a rhythmic unit, usually conforming to the metric structure indicated by a time signature, and delineated on either side by a bar line. A column is an invisible horizontal unit equal to the height of a staff degree. Columns extend vertically throughout the system, and are the basis both for vertical alignment of musical characters, and for determination of time-events within the score.

The editor incorporates standard word-processor-like block functions such as cut, copy, paste, paste-special, delete, and clear, as well as word-processor-like formatting functions such as justification and pagination. The editor also incorporates music-specific block functions such as overlay, transpose, add or remove beams, reverse or optimize stem directions, and divide or combine voices, etc. Music-specific formatting options are further provided, such as pitch respelling, chord optimization, vertical alignment, rhythmic-value change, insertion of missing rests and time signatures, placement of lyrics, and intelligent extraction of individual instrumental or vocal parts. While in the client workspace of the editor, the cursor alternates, on a context-sensitive basis, between a blinking music character restricted to logical locations on the musical staff ("columns" and "staff degrees") and a non-restricted pointer cursor.

Unlike prior art musical software systems, the editor of the present invention enables the operator to double-click on a character in a score to automatically cause that character to become a new cursor character. This enables complex cursor characters, such as chords, octaves, and thirds, etc. to be selected into the cursor, which is referred to as cursor character morphing. Thus, the operator does not have to enter each note in the chord one at a time or copy, paste, and move a chord, both of which require several keystrokes.

The editor of the present invention also provides an automatic timing calculation feature that accepts operator entry of a desired elapsed time for a musical passage. This is important to the film industry, for example, where there is a need to calculate the speed of musical performances such that the music coordinates with certain "hit" points in films, television, and video. The prior art practices involve the composer approximating the speeds of different sections of music using metronome indications in the score. For soundtrack creation, performers use these indications to guide them to arrive on time at "hit" points. Often, several recordings are required before the correct speeds are accomplished and a correctly-timed recording is made. The editor of the present invention eliminates the need for making several recordings by calculating the exact tempo needed. The moving playback cursor for a previously-calculated playback session can be used as a conductor guide during recording sessions with live performers. This feature allows a conductor to synchronize the live conducted performance correctly without the need for conventional click tracks, punches or streamers.

Unlike prior art, tempo nuances are preserved even when overall tempo is modified, because tempo is controlled by adjusting the note values themselves, rather than the clock speed (as in standard MIDI.) The editor preferably uses a constant clock speed equivalent to a metronome mark of 140. The note values themselves are then adjusted in accordance with the notated tempo (i.e., quarter notes at an andante speed are longer than at an allegro speed.) All tempo relationships are dealt with in this way, including fermatas, tenutos, breath commas and break marks. The clock speed can then be changed globally, while preserving all the inner tempo relationships.

After the user inputs the desired elapsed time for a musical passage, global calculations are performed on the stored duration of each timed event within a selected passage, thereby preserving variable speeds within the sections (such as ritardandos, accelerandos, a tempi), if any, to arrive at the correct timing for the overall section. Depending on user preference, metronome markings may either be automatically updated to reflect the revised tempi, or they may be preserved, and kapt "hidden," for playback only. The editor calculates and stores the duration of each musical events preferably in units of 1/44100 of a second. Each timed event's stored duration is than adjusted by a factor (x = current duration of passage/desired duration of passage) to result in an adjusted overall duration of the selected passage. A time orientation status bar m the interface may show elapsed minutes, seconds, and SMPTE frames or elapsed minutes, seconds, and hundredth of a second for the corresponding notation area.

The editor of the present invention further provides a method for directly editing certain performance aspects of a single note, chord, or musical passage, such as the attack, volume envelope, onset of vibrato, trill speed, staccato, legato connection, etc. This is achieved by providing a graphical representation that depicts both elapsed time and degrees of application of the envelope. The editing window is preferably shared for a number of micro-editing functions. An example of the layout for the user interface is shown in Figure 1.

The editor also provides a method for directly editing parming motion or orientation on a single note, chord or musical passage. The editor supports two and four-channel panning- The user interface may indicate the duration in note value units, by the user entry line itself, as shown in Figure 2.

Prior art musical software systems support the entry of MIDI code and automatic translation of MIDI code into music notation in real time. These systems allow the user to define entry parameters (pulse, subdivision, speed, number of bars, starting and ending points) and then play music in time to a series of rhythmic clicks, used for synchronization purposes. Previously-entered music can also be played back during entry, in which case the click can be disabled if unnecessary for synchronization purposes. These prior art systems, however, make it difficult to enter tuplets (or rhythmic subdivisions of the pulse which are notated by bracketing an area, indicating the number of divisions of the pulse). Particularly, the prior art systems usually convert tuplets into technically correct, yet highly-unreadable notation, often notating minor discrepancies in the rhythm that the user did not intend, as well.

The editor of the present invention overcomes this disadvantage while still translating incoming MIDI into musical notation in real time, and importing and converting standard MIDI files into notation. Specifically, the editor allows the entry of music data via a MIDI instrument, on a beat-by-beat basis, with the operator determining each beat point by pressing an indicator key or pedal. Unlike the prior art, in which the user must time note entry according to an external click track, this method allows the user to play in segments of music at any tempo, so long as he remains consistent within that tempo during that entry segment. This method has the advantage of allowing any number of subdivisions, tuplets, etc. to be entered, and correctly notated.

Database

The database is the core data structure of the software system of the present invention, that contains, in concise form, the information for writing the score on a screen or to a printer, and/or generating a musical performance. In particular, the database of the present invention provides a sophisticated data structure that supports the graphical symbols and information that is part of a standard musical score, as well as the performance generation information that is implied by the graphical information and is produced by live musicians during the course of interpreting the graphical symbols and information in a score.

The code entries of the data structure are in the form of 16-bit words, generally in order of Least Significant Bit (LSB) to Most Significant Bit (MSB), as follows: <ul id="ul0002" list-style="bullet" compact="compact"><li>0000h (0) - 003Fh (63) are Column Staff Markers</li><li>0040h (64) - 00FFh (255) are Special Markers</li><li>0100h (256) - 0FEFFh (65279) are Character ID's together with Staff Degrees</li><li>0FF00h (65280) - OFFFFh (65535) are Data Words. Only the LSB is the datum.</li><li>Character ID's are arranged into "pages" of 256 each.</li><li>Character ID's are the least significant 10 bits of the two-byte word. The most significant 6 bits are the staff degree.</li><li>Individual Characters consist of: Character ID and Staff Degree combined into a single 16-bit word.</li></ul>

Specific markers are used in the database to delineate logical columns and staff areas, as well as special conditions such as the conclusion of a graphic or performance object. Other markers may be used to identify packets, which are data structures containing graphic and/or performance information organized into logical units. Packets allow musical objects to be defined and easily manipulated during editing, and provide information both for screen writing and for musical performance. Necessary intervening columns are determined by widths and columnar offsets, and are used to provide distance between adjacent objects. Alignment control and collision control are functions which determine appropriate positioning of objects and incidental characters in relation to each other vertically and horizontally, respectively.

Unlike prior art music software systems, the database of the present invention has a small footprint so it is easily stored and transferred via e-mail to other workstations, where the performance data can be derived in real time to generate the exact same performances as on the original workstation. Therefore, this database addresses the portability problem that exists with the prior art musical file formats such as .WAV and .MP3. These file types render identical performances on any workstation but they are extremely large and difficult to store and transport.

Font

The font of the present invention is a unicoded, truetype musical font that is optimal for graphic music representation and musical performance encoding. In particular, the font is a logical numbering system that corresponds to musical characters and glyphs that can be quickly assembled into composite musical characters in such a way that the relationships between the musical symbols are directly reflected in the numbering system. The font also facilitates mathematical calculations (such as for transposition, alignment, or rhythm changes) that involve manipulation of these glyphs. Hexadecimal codes are assigned to each of the glyphs that support the mathematical calculations. Such hexadecimal protocol may be structured in accordance with the following examples: <dl id="dl0001" compact="compact"><dt>0</dt><dd>Rectangle (for grid calibration)</dd><dt>1</dt><dd>Vertical Line (for staff line calibration)</dd><dt>2</dt><dd>Virtual bar line (non-print)</dd><dt>3</dt><dd>Left non-print bracket</dd><dt>4</dt><dd>Right non-print bracket</dd><dt>5</dt><dd>Non-print MIDI patch symbol</dd><dt>6</dt><dd>Non-print MIDI channel symbol</dd><dt>(7-FF)</dt><dd>reserved</dd><dt>100</dt><dd>single bar line</dd><dt>101</dt><dd>double bar line</dd><dt>102</dt><dd>front bar line</dd><dt>103</dt><dd>end bar line</dd><dt>104</dt><dd>stem extension up, 1 degree</dd><dt>105</dt><dd>stem extension up, 2 degrees</dd><dt>106</dt><dd>stem extension up, 3 degrees</dd><dt>107</dt><dd>stem extension up, 4 degrees</dd><dt>108</dt><dd>stem extension up, 5 degrees</dd><dt>109</dt><dd>stem extension up, 6 degrees</dd><dt>10A</dt><dd>stem extension up, 7 degrees</dd><dt>10B</dt><dd>stem extension up, 8 degrees</dd><dt>10C</dt><dd>stem extension down, 1 degree</dd><dt>10D</dt><dd>stem extension down, 2 degrees</dd><dt>10E</dt><dd>stem extension down, 3 degrees</dd></dl>

Compiler

The compiler component of the present invention is a set of routines that generates performance code from the data in the database, described above. Specifically, the compiler directly interprets the musical symbols, artistic interpretation instructions, note-shaping "micro-editing" instructions, and other indications encoded in the database, applies context-sensitive artistic interpretations that are not indicated through symbols and/or instructions, and creates performance-generation code for the synthesizer, which is described further below.

The performance generation code format is similar to the MIDI code protocol, but it includes the following enhancements for addressing the limitations with standard MIDI: <ul id="ul0003" list-style="bullet"><li>The code is in a single-track event-sequence form. All commands that are to occur simultaneously are grouped together, and each such group is followed by a single timing value.</li><li>Program change commands have three bytes. The command byte is 0C0h. The first data byte is the channel number (0-127), the 2^nd and 3^rd data bytes form a 14-bit Program number. This enhancement provides for up to 128 channels, and up to 16384 program numbers.</li><li>Program Preloading Commands are formatted like Program Change Commands except that the command byte is 0C1h, rather than 0C0h. This enhancement allows Programs to be loaded into memory just before they are needed.</li><li>Program Cancellation Commands are the same as Program Change commands except that the command byte is 0C2h, rather than 0C0h. This enhancement allows Programs to be released from memory when they are no longer needed.</li><li>Note-on commands have four bytes. The command byte is 90h. The first data byte is the channel number. The second data byte is the pitch number. The third data byte specifies envelope parameters, including accent and overall dynamic shape. This enhancement supports envelope shaping of individual notes.</li><li>Note-off commands have four bytes. The command byte is 91h. The first data byte is the channel number. The second data byte is the pitch number. The third data byte specifies decay shape. This enhancement supports envelope shaping of the note's release, including crossfading to the next note for legato connection.</li><li>Channel Volume commands have four bytes. The command byte is 0B0h. The first data byte is the channel number. The second and third data bytes form a 14-bit volume value. This enhancement provides much wider range of volume control than MIDI, eliminating "bumpy" changes, particularly at lower volumes.</li><li>Individual Volume commands have five bytes. The command byte is 0A0h. The first data byte is the Channel. The second and third data bytes form a 14-bit volume value. The fourth data byte is the individual pitch number. This replaces the velocity command in the MIDI specification to allow volume control of individual notes.</li><li>Channel Pitch bend commands have four bytes. The command byte is 0B1h. The first data byte is the channel number. The second data byte determines whether this is a simple re-tuning of the pitch (0) or a pre-determined algorithmic process such as a slide, fall or legato pitch connection. The third data byte is the tuning value as a 7-bit signed number. This enhancement supports algorithmic pitch bend shaping.</li><li>Individual Pitch bend commands have five bytes. The command byte is 0A1h. The first data byte is the channel number. The second data byte determines whether this is a simple re-tuning of the pitch (0) or an algorithmic process such as a slide, fall or legato pitch connection. The third data byte is the tuning value as a 7-bit signed number. The fourth data byte is the pitch number. This enables support of algorithmic pitch bend shaping of individual notes.</li><li>Channel Pan commands have four bytes. The command byte is 0B2h. The first data byte is the channel number. The second data byte determines right/left position, and the third data byte determines front/back position of the sound. This enhancement supports algorithmic surround sound panning (stationary and in motion).</li><li>Individual Pan commands have five bytes. The command byte is 0A2h. The first data byte is the channel number. The second data byte determines right/left position and the third data byte determines front/back position of the sound. The fourth data byte is the pitch number. This enhancement applies surround-sound panning to individual notes.</li><li>Channel Pedal commands have three bytes. The command byte is 0B3h. The first data byte is the channel number. The second data byte has the value of either 0 (pedal off) or 1 (pedal on).</li><li>Individual Pedal commands have three bytes. The command byte is 0A3h. The first data byte is the channel number. The second data byte has the value of either 0 (pedal off) or 1 (pedal on). The third data byte selects the individual pitch to which the pedal is to be applied. This enhancement applies pedal capability to individual notes.</li><li>Special Micro-Editing channel commands have three bytes. The command byte is 0B4h. The first data byte is the channel number. The second data byte determines the specific micro-editing format. This enhancement allows a number of digital processing techniques to be applied.</li><li>Individual Micro-editing commands have four bytes. The command byte is 0B4h. The first data byte is the channel number. The second data byte determines the specific micro-editing format. The third data byte is the pitch number. This enhancement allows digital processing techniques to be applied on an individual note basis.</li><li>Timing commands are as follows: 0F0h, followed by 3 data bytes, which are concatenated to form a 21-bit timing value (up to 2097151 = number of digital samples in 47.5 seconds @ 44100 Hz). Note that a timing command is actually the number of digital samples processed at 44.1 KHz. This enhancement allows precision timing independent of the computer clock, and directly supports wave file creation.</li><li>Playback timing is determined by adjusting the note values themselves, rather than the clock speed (as in Standard MIDI.) The invention uses a constant speed equivalent to the number of digital samples to be processed at 44.1KHz. Thus a one-second duration is equal to a value of 44,100. The invention adjusts individual note values are adjusted in accordance with the notated tempo (i.e., quarter notes at a slow speed are longer than quarter notes at a fast speed.) All tempo relationships are dealt with in this way, including fermatas, tenutos, breath commas and break marks. This enhancement allows the playback speed to be changed globally, while preserving all inner tempo relationships.</li><li>There is also a five-byte Timing Report (OF1h) used in calculations for SMPTE and other timing function synchronization.</li><li>The invention interprets arpeggio, fingered tremolando, slide, glissando, beamed accelerando and ritardando groups, portamenteau symbols, trills, mordents, inverted mordents, staccato and other articulations, and breath mark symbols into performance generation code, including automatic selection of MIDI patch changes where required.</li><li>Automatic selection of instrument-specific patch changes, using instrument names, performance directions (such as pizzicato, col legno, etc.) and notational symbols indicating staccato, marcato, accent, or legato.</li></ul>

Thus, while prior art music notation software programs create a limited MIDI playback of the musical score, the present invention's rendering of the score into performance code is unique in the number and variety of musical symbols it translates, and in the quality of performance it creates thereby.

Performance Generator

The performance generator reads the proprietary performance code file created by the compiler, and sends commands to the software synthesizer and the screen-writing component of the editor at appropriate timing intervals, so that the score and a moving cursor can be displayed in synchronization with the playback. In general, the timing of the performances may come from four possible sources: (1) the internal timing code, (2) external MIDI Time Code (SMPTE), (3) user input from the computer keyboard or from a MIDI keyboard, and (4) timing information recorded during a previous user-controlled session. The performance generator also includes controls which allow the user to jump to, and begin playback from, any point within the score, and/or exclude any instruments from playback in order to select desired instrumental combinations.

When external SMPTE Code is used to control the timing, the performance generator determines the exact position of the music in relation to the video if the video starts within the musical cue, or waits for the beginning of the cue if the video starts earlier.

As mentioned above, the performance generator also allows the user to control the timing of a performance in real time. This may be achieved by the user pressing specially-designated keys in conjunction with a special music area in the score that contains the rhythms that are needed control the performance. Users may create or edit the special music area to fit their own needs. Thus, this feature enables intuitive control over tempo in real time, for any trained musician, without requiring keyboard proficiency or expertise in sequencer equipment.

There are two modes in which this feature can be operated. In normal mode, each keypress immediately initiates the next "event." If a keypress is early, the performance skips over any intervening musical events; if a keypress is late, the performance waits, with any notes on, for the next event. This allows absolute user control over tempo on an event-by-event basis. In the "nudge" mode, keypresses do not disturb the ongoing flow of music, but have a cumulative effect on tempo over a succession of several events. Special controls also support repeated and "vamp until ready" passages, and provide easy transition from user control to automatic internal clock control (and vice versa) during playback.

Some additional features of the performance generator include the incorporation of all rubato interpretations built into the musical score within the tempo fluctuations created by user keypresses and a music control staff area that allows the user to set up the exact controlling rhythms in advance. This allows variations between beats and beat subdivisions, as needed.

Also noted above, the timing information may come from data recorded during a previous user-controlled session. In this case, the timing of all user-keystrokes in the original session is stored for subsequent use as an automatic triggering control that renders an identically-timed performance.

Synthesizer

The software synthesizer responds to commands from the performance generator. It first creates digital data for acoustical playback, drawing on a library of digital sound samples. The sound sample library is a comprehensive collection of digital recordings of individual pitches (single notes) played by orchestral and other acoustical instruments. These sounds are recorded and constitute the "raw" material used to create the musical performances. The protocol for these preconfigured sampled musical sounds is automatically derived from the notation itself, and includes use of different attacks, releases, performance techniques and dynamic shaping for individual notes, depending on musical context.

The synthesizer then forwards the digital data to a direct memory access buffer shared by the computer sound card. The sound card converts the digital information into analog sound that may be output in stereo or quadraphonic, or orchestral seating mode. Unlike prior art software systems, however, the present invention does not require audio playback in order to create a WAVE or MP3 sound file. Rather, WAVE or MP3 sound files may be saved directly to disk.

The present invention also applies a set of processing filters and mixers to the digitally recorded musical samples stored as instrument files in response to commands in the performance generation code. This results in individual-pitch, volume, pan, pitchbend, pedal and envelope controls, via a processing "cycle" that produces up to three stereo 16-bit digital samples, depending on the output mode selected. Individual samples and fixed pitch parameters are "activated" through reception of note-on commands, and are "deactivated" by note-off commands, or by completing the digital content of non-looped samples. During the processing cycle, each active sample is first processed by a pitch filter, then by a volume filter. The filter parameters are unique to each active sample, and include fixed patch parameters and variable pitchbend and volume changes stemming from incoming channel and individual-note commands or through application of special preset algorithmic parameter controls. The output of the volume filter is then sent to panning mixers, where it is processed for panning and mixed with the output of other active samples. At the completion of the processing cycle, the resulting mix is sent to a maximum of three auxiliary buffers, and then forwarded to the sound card.

The synthesizer of the present invention is capable of supporting four separate channels for the purpose of generating in surround sound format and six separate channel outputs for the purpose of emulating instrument placement in specific seating arrangements for large ensembles, unlike prior art systems. The synthesizer also supports an "active" score playback mode, in which an auxiliary buffer is maintained, and the synthesizer receives timing information for each event well in advance of each event. The instrument buffers are dynamically created in response to instrument change commands in the performance generation code. This feature enables the buffer to be ready ahead of time, and therefore reduces latency. The synthesizer also includes an automatic crossfading feature that is used to achieve a legato connection between consecutive notes in the same voice. Legato crossfading is determined by the compiler from information in the score.

Accordingly, the present invention integrates music notation technology with a unique performance generation code and a synthesizer pre-loaded with musical instrument files to provide realistic playback of music scores. The user is able to generate and playback scores without the need of separate synthesizers, mixers, and other equipment.

Certain modifications and improvements will occur to those skilled in the art upon a reading of the foregoing description. For example, the performance generation code is not limited to the examples listed. Rather, an infinite number of codes may be developed to represent many different types of sounds.