Note: Descriptions are shown in the official language in which they were submitted.
CA 02527066 2005-11-15
A METHOD AND SYSTEM FOR FILTERING WAVETABLE
INFORMATION FOR WIRELESS DEVICES
FIELD OF THE APPLICATION
[0001] This application relates to the field of wavetable information, and
more
specifically, to filtering wavetable information prior to downloading to a
wireless device.
BACKGROUND
[0002] Current wireless mobile communication devices include microprocessors,
memory, soundcards, and run one or more software applications. Examples of
software
applications used in these wireless devices include micro-browsers, address
books, email
clients, and wavetable instruments. Additionally, wireless devices have access
to a
plurality of services via the Internet. A wireless device may, for example, be
used to
browse web sites on the Internet, to transmit and receive graphics, and to
execute
streaming audio and/or video applications. The transfer of Internet content to
and from
wireless device is typically facilitated by the Wireless Application Protocol
("WAP"),
which integrates the Internet and other networks with wireless network
platforms.
[0003] A wavetable instrument is an application that digitally models a real
instrument (e.g., a piano, etc.) using information from a wavetable file. A
waveable
instrument may allow a user to "play" songs by depressing one or more keyboard
keys,
etc., thus providing interactive audio.
[0004] The content of the wavetable file includes captured audio samples of
the
instrument combined with various configuration settings in order to provide an
approximation of the sound of the instrument at any note or pitch.
Downloadable
wavetable content is wavetable content stored in a file having a specific file
format that
can be downloaded to a user system, such as a wireless device or personal
computer, for
storage in system memory or in the memory of the system's soundcard or audio
synthesizer. In addition to wavetable instruments, downloadable wavetable
content can
be used for applications such as music for games, web pages, and polyphonic
ringtones.
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Downloadable wavetable content can provide consistent sounding audio across
all
platforms while requiring only a fraction of the storage resources required by
other audio
files such as MP3s. Examples of downloadable wavetable data file formats
include the
Downloadable Sounds ("DLS") file format from the Musical Instruments Digital
Interface ("MIDI") Manufacturers Association and the SoundFont~ file format
from
Creative Labs, Inc.
[0005] Thus, wavetable content may be downloaded from a network such as the
Internet by a wireless device for playback through a wavetable instrument
application via
the device's soundcard or audio synthesizer.
[0006] However, one shortcoming of present wireless devices and wireless
communications systems is their inability to efficiently download such
wavetable content
to wireless devices. For example, optimizing the size and level of detail when
creating
wavetable instruments that are to be downloaded via network communications
onto a
push-enabled wireless device cannot be done in advance because capabilities of
different
wireless devices vary and the amount of resources (e.g., flash memory,
remaining carrier-
enforced data limits, etc.) available is limited and constantly changing due
to the arrival
of new messages, calendar appointments, etc. The need to efficiently download
wavetable content is increasing in importance with the increase in the number
of
applications being run on wireless devices.
[0007] European Patent Application Publication No. EP 1251488A discloses a
system for downloading music data as content distribution data from a
distribution centre
via the general telephone network into mobile telephones. Downloaded content
distribution data are stored in a memory of a mobile telephone.
[0008] U.S. Patent Application Publication No. 2004/0044781 discloses a
service
provider network including a memory for storing subscriber information of a
subscriber
device and a data engine for receiving a generic data request from the
subscriber device.
The network includes an intelligent proxy server for receiving the data from
the data
engine in response to a subscriber device request, manipulating or filtering
the data as a
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function of the subscriber information to thin the content of the data, and
outputting the
filtered data to the subscriber device.
[0009] A need therefore exists for an improved method and system of
downloading
wavetable information to wireless devices. Accordingly, a solution that
addresses, at least
in part, the above and other shortcomings is desired.
SUMMARY
[0010] According to one aspect of the application, there is provided a method
in a
proxy server for providing wavetable information to a wireless device from a
content
server over a wireless network, the wavetable information including a
plurality of
samples corresponding to a plurality of notes, comprising: in response to a
request from
the wireless device, receiving at the proxy server the wavetable information
from the
content server; filtering the wavetable information in accordance with a
selection of
samples contained in the request; and transmitting the filtered wavetable
information to
the wireless device.
[0011] Preferably, the method further includes the proxy server receiving a
request
for metadata for the wavetable information from the wireless device, the
metadata
including sample sizes for the samples.
[0012] Preferably, the method further includes, in response to the request for
metadata, the proxy server transmitting the metadata to the wireless device.
[0013] Preferably, the method further includes the proxy server receiving the
metadata from the content server.
[0014] Preferably, the method further includes the proxy server extracting the
metadata from the wavetable information.
[0015] Preferably, the wireless device is adapted for calculating a desired
number of
samples for the selection of samples from a maximum of the sample sizes and an
amount
of available memory in the wireless device.
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[0016] Preferably, the wireless device is further adapted for determining the
selection
of samples by forming groups of notes based on spacings between the notes,
allocating
one of the desired number of samples to each group, and selecting a sample for
the notes
in each group that corresponds to a note at a midpoint of the group to reduce
distortion.
[0017] According to another aspect of the application, there is provided a
method for
providing wavetable information to a wireless device from a content server
over a
wireless network, the wavetable information including a plurality of samples
corresponding to a plurality of notes, comprising: in response to a request
from the
wireless device, receiving at a proxy server the wavetable information from
the content
server; filtering the wavetable information in accordance with an amount of
available
memory in the wireless device as contained in the request; and transmitting
the filtered
wavetable information to the wireless device.
[0018] Preferably, the filtering further comprises calculating a desired
number of
samples from a maximum of the sample sizes and the amount of available memory
in the
wireless device.
[0019] Preferably, the filtering further comprises determining a selection of
samples
by forming groups of notes in accordance with spacings between the notes,
allocating one
of the desired number of samples to each group, and selecting a sample for the
notes in
each group that corresponds to a note at a midpoint of the group to reduce
distortion.
[0020] According to another aspect of the application, there is provided a
method for
filtering wavetable information in a wireless device, the wavetable
information including
a plurality of samples corresponding to a plurality of notes, comprising:
calculating a desired number of samples from a maximum of the sample sizes and
an
amount of available memory in the wireless device; and determining a selection
of
samples by forming groups of notes in accordance with spacings between the
notes,
allocating one of the desired number of samples to each group, and selecting a
sample for
CA 02527066 2005-11-15
the notes in each group that corresponds to a note at a midpoint of the group
to reduce
distortion.
[0021] In accordance with further aspects of the present application there is
provided
an apparatus such as a proxy server system, a method for adapting this system,
as well as
articles of manufacture such as a computer readable medium having program
instructions
recorded thereon for practising the method of the application.
[0022] These and other aspects and features of the present application will
become
apparent to persons of ordinary skill in the art upon review of the following
detailed
description, taken in combination with the appended drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0023] FIG. 1 is a block diagram illustrating a proxy server system adapted
for
implementing an embodiment of the application;
[0024] FIG. 2 is a block diagram illustrating a wireless communications system
adapted for implementing an embodiment of the application;
[0025] FIG. 3 is a flow chart illustrating operations of modules within the
wireless
communications system and wireless device for filtering wavetable content in
accordance
with an embodiment of the application;
[0026] FIG. 4 is a block diagram illustrating a wavetable instrument (e.g., a
piano)
containing a single keysplit region over a two octave range in accordance with
an
embodiment of the application;
[0027] FIG. 5 is a block diagram illustrating a wavetable instrument
containing two
keysplit regions over a two octave range in accordance with an embodiment of
the
application;
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[0028] FIG. 6 is a block diagram illustrating a wavetable instrument
containing two
keysplit regions over a two octave range in accordance with an embodiment of
the
application;
[0029] FIG. 7 is a block diagram illustrating a wavetable instrument
containing two
keysplit regions having ranges that span the notes starting at the D note of
the first octave
through the A note of the second octave in accordance with an embodiment of
the
application;
[0030] FIG. 8 is a block diagram illustrating a wavetable instrument
containing two
keyplit regions having ranges that span two disjoint subsets of notes starting
at the D note
of the first octave through the A note of the second octave in accordance with
an
embodiment of the application;
[0031] FIG. 9 is a flow chart illustrating operations of modules within the
wireless
communications system for determining keysplit regions and associated samples
for a
wavetable instrument in accordance with an embodiment of the application;
[0032] FIG. 10 is a flow chart illustrating operations of modules within the
wireless
communications system for adjusting the keysplit regions and associated
samples in
accordance with an embodiment of the application;
[0033] FIG. 11 is a block diagram illustrating an exemplary wireless device
adapted
in accordance with an embodiment of the application; and
[0034] FIG. 12 is a block diagram illustrating a memory of the wireless device
of
FIG. 11 in accordance with an embodiment of the application.
[0035] It will be noted that throughout the appended drawings, like features
are
identified by like reference numerals.
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DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0036] The following detailed description of the embodiments of the present
application does not limit the implementation of the application to any
particular
computer programming language. The present application may be implemented in
any
computer programming language provided that the operating system provides the
facilities that may support the requirements of the present application. A
preferred
embodiment is implemented in the JavaTM computer programming language (or
other
computer programming languages such as C or C++). (Java and all Java-based
trademarks are the trademarks of Sun Microsystems Corporation.) Any
limitations
presented would be a result of a particular type of operating system or
computer
programming language and would not be a limitation of the present application.
[0037] The present application is directed to resource availability problems
such as
may be encountered when downloading wavetable information onto a wireless
device for
use with audio playback applications. Wavetable data files are generally
considered to be
compact when compared to alternative audio formats. However, as these files
are
typically created and used on desktop computers they are often too large or
detailed for
most mobile wireless devices. For example, the files may contain compact disc
("CD")
quality samples, while the wireless device hardware may not be capable of CD
quality
audio output. The size and detail of the samples in this case would be
wasteful.
[0038] Embodiments of the application provide a method for a mobile wireless
device to request a remote proxy server to download and filter out samples
from a
wavetable data file available from a content server. Requesting a proxy server
to perform
the filtering is a more economical use of the wireless device's airtime. The
wavetable
data file transferred from the proxy to the device in accordance with the
application is
typically smaller than if that same wavetable data file was downloaded
directly from the
content server.
[0039] The filtering is performed based on information regarding which samples
should be kept in the wavetable instrument (the rest are filtered out). This
information is
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g
calculated by the wireless device or client based on variables such as the
desired
maximum size of a resulting wavetable instrument and which MIDI instructions
will be
used by the wireless device to play the wavetable instrument. Knowing which
MIDI data
will be used to drive the instrument allows for efficient filtering for the
instrument in
order to retain as much audio quality as possible.
[0040] In addition, the download process can be automated. For example, if a
user
downloads a game, the game application can follow up by automatically
downloading
wavetable content to be used for the game's background music upon the first
run of the
application. Furthermore, the download process can be interactive. For
example, a user
may wish to download a wavetable instrument that will be used to generate the
sound for
a specific set of MIDI/SP-MIDI ringtones. If the wavetable data file to be
downloaded is
one specified by a user, very little interaction is required in the download
process. The
user specifies the remote location of the wavetable data file desired for
download and a
set of MIDI files which will be used to play the wavetable instrument.
[0041] Advantageously, the present application provides an automated method of
reducing the size of a wavetable data file at runtime without manual editing.
Currently, if
a user wishes to reduce the size of a wavetable file, the user would have to
download the
entire file and manually edit the resource file using editing software. Not
only is
downloading the entire file before local editing uneconomical, it is not a
trivial task as it
requires knowledge of the specific file format and how wavetables operate.
[0042] FIG. 1 is a block diagram illustrating a proxy server system 100
adapted for
implementing an embodiment of the application. The proxy server system 100
includes
an input device 110, a central processing unit or CPU 120, memory 130, a
display 140,
and an interface 150. The input device 110 may include a keyboard, mouse,
trackball,
remote control, or similar device. The CPU 120 may include dedicated
coprocessors and
memory devices. The memory 130 may include RAM, ROM, or disk devices. The
display 140 may include a computer screen, terminal device, or a hardcopy
producing
output device such as a printer or plotter. And, the interface 150 may include
a network
connection including an Internet connection. The proxy server 100 is adapted
for filtering
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and downloading wavetable information to wireless devices 210 over a wireless
network
220 (see FIG. 2).
[0043] The proxy server system 100 may be a server system or a personal
computer
("PC") system. The CPU 120 of the system 100 is operatively coupled to memory
130
which stores an operating system (not shown), such as IBM Corporation's
OS/2TM,
UNIX, etc., for general management of the system 100. The interface 150 may be
used
for communicating to external data processing systems 230, 250 through a
network 240
(see FIG. 2), such as the Internet. Examples of suitable platforms for the
proxy server
system 100 include iSeriesTM servers and ThinkCentreTM personal computers
available
from IBM Corporation. The system 100 may include application server software
(not
shown), such as WebLogic~ Server available from BEA Systems, Inc., for
developing
and managing distributed applications.
[0044] The proxy server system 100 may include a database system 160 for
storing
and accessing programming information. The database system 160 may include a
database management system ("DBMS") and a database and is stored in the memory
130
of the proxy server system 100.
[0045] The proxy server system 100 includes computer executable programmed
instructions for directing the system 100 to implement the embodiments of the
present
application. The programmed instructions may be embodied in one or more
software
modules 170 resident in the memory 130 of the proxy server system 100.
Alternatively,
the programmed instructions may be embodied on a computer readable medium
(such as
a CD disk or floppy disk) which may be used for transporting the programmed
instructions to the memory 130 of the proxy server system 100. Alternatively,
the
programmed instructions may be embedded in a computer-readable, signal-bearing
medium that is uploaded to a network by a vendor or supplier of the programmed
instructions, and this signal-bearing medium may be downloaded through the
interface
150 to the proxy server system 100 from the network by end users or potential
buyers.
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[0046] The CPU 120 of the system 100 is typically coupled to one or more
devices
110 for receiving user commands or queries and for displaying the results of
these
commands or queries to the user on a display 140. As mentioned, the memory 130
may
include a variety of storage devices including internal memory and external
mass storage
typically arranged in a hierarchy of storage as understood to those skilled in
the art.
[0047] A user may interact with the proxy server system 100 and its software
modules 170 using a graphical user interface ("GUI") 180. The GUI 180 may be
web-
based and may be used for monitoring, managing, and accessing the proxy server
system
100. GUIs are supported by common operating systems and provide a display
format
which enables a user to choose commands, execute application programs, manage
computer files, and perform other functions by selecting pictorial
representations known
as icons, or items from a menu through use of an input or pointing device such
as a
mouse 110. In general, a GUI is used to convey information to and receive
commands
from users and generally includes a variety of GUI objects or controls,
including icons,
toolbars, drop-down menus, text, dialog boxes, buttons, and the like. A user
typically
interacts with a GUI 180 presented on a display 140 by using an input or
pointing device
(e.g., a mouse) 110 to position a pointer or cursor 190 over an object 191 and
by
"clicking" on the object 191.
[0048] Typically, a GUI based system presents application, system status, and
other
information to the user in "windows" appearing on the display 140. A window
192 is a
more or less rectangular area within the display 140 in which a user may view
an
application or a document. Such a window 192 may be open, closed, displayed
full
screen, reduced to an icon, increased or reduced in size, or moved to
different areas of the
display 140. Multiple windows may be displayed simultaneously, such as:
windows
included within other windows, windows overlapping other windows, or windows
tiled
within the display area.
[0049] FIG. 2 is a block diagram illustrating a wireless communications system
200
adapted for implementing an embodiment of the application. The wireless
communications system 200 includes a wireless device 210 in communication with
the
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proxy server system 100 over a wireless network 220. The wireless network 220
is
coupled to a wireless network gateway 230 which provides an interface to a
wide area
network ("WAN") 240 to which the proxy server I00 is coupled. The proxy server
100
is also in communication with a content server system 250 over the WAN 240.
[0050] FIG. 11 is a block diagram illustrating an exemplary wireless device
210
adapted in accordance with an embodiment of the application. The wireless
device 210 is
a two-way communication device having at least voice and advanced data
communication capabilities, including the capability to communicate with other
computer
systems. Depending on the functionality provided by device 210, it may be
referred to as
a data messaging device, a two-way pager, a cellular telephone with data
messaging
capabilities, a wireless Internet appliance, or a data communication device
(with or
without telephony capabilities). Device 210 may communicate with any one of a
plurality
of fixed transceiver stations 220 within its geographic coverage area.
[0051] Device 210 will normally incorporate a communication subsystem I11,
which
includes a RF receiver, a RF transmitter, and associated components, such as
one or more
(preferably embedded or internal) antenna elements and, local oscillators
("LOs"), and a
processing module such as a digital signal processor ("DSP") (all not shown).
As will be
apparent to those skilled in field of communications, particular design of
communication
subsystem 111 depends on the communication network 220 in which device 210 is
intended to operate.
[0052] Network access is associated with a subscriber or user of device 210
and
therefore device 210 requires a Subscriber Identity Module (or "SIM" card) 162
to be
inserted in a SIM IF 164 in order to operate in the network. Device 210 is a
battery-
powered device so it also includes a battery IF 154 for receiving one or more
rechargeable batteries 156. Such a battery 156 provides electrical power to
most if not all
electrical circuitry in device 210, and battery IF 154 provides for a
mechanical and
electrical connection for it. The battery IF 154 is coupled to a regulator
(not shown)
which provides power V+ to all of the circuitry.
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[0053] Device 210 includes a microprocessor 138 which controls overall
operation of
device 210. Communication functions, including at least data and voice
communications,
are performed through communication subsystem 111. Microprocessor 138 also
interacts
with additional device subsystems such as a display 122, a flash memory 124 or
other
persistent store, a random access memory ("RAM") 126, auxiliary input/output
("I/O")
subsystems 128, a serial port 131, a keyboard 132, a speaker 134, a microphone
136, a
short-range communications subsystem 141, and any other device subsystems
generally
designated at 142. Some of the subsystems shown in FIG. 1 perform
communication-
related functions, whereas other subsystems may provide "resident" or on-
device
functions. Notably, some subsystems, such as keyboard 132 and display 122, for
example, may be used for both communication-related functions, such as
entering a text
message for transmission over a communication network, and device-resident
functions
such as a calculator or task list. Operating system software used by
microprocessor 138 is
preferably stored in a persistent store such as flash memory 124, which may
alternatively
be a read-only memory ("ROM") or similar storage element (not shown). Those
skilled in
the art will appreciate that the operating system, specific device
applications, or parts
thereof, may be temporarily loaded into a volatile store such as RAM 126.
[0054] Microprocessor 138, in addition to its operating system functions,
preferably
enables execution of software applications on device 210. A predetermined set
of
applications which control basic device operations, including at least data
and voice
communication applications, will normally be installed on device 210 during
its
manufacture. A preferred application that may be loaded onto device 210 may be
a
personal information manager ("PIM") application having the ability to
organize and
manage data items relating to the user such as, but not limited to, instant
messaging
("IM"), e-mail, calendar events, voice mails, appointments, and task items.
Naturally,
one or more memory stores are available on device 210 and SIM 162 to
facilitate storage
of PIM data items and other information.
[0055] The PIM application preferably has the ability to send and receive data
items
via the wireless network 220. In a preferred embodiment, PIM data items are
seamlessly
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integrated, synchronized, and updated via the wireless network, with the
mobile station
user's corresponding data items stored and/or associated with a host computer
system
thereby creating a mirrored host computer on device 210 with respect to such
items. This
is especially advantageous where the host computer system is the mobile
station user's
office computer system. Additional applications may also be loaded onto device
210
through network 220, an auxiliary I/O subsystem 128, serial port 131, short-
range
communications subsystem 141, or any other suitable subsystem 142, and
installed by a
user in RAM 126 or preferably a non-volatile store (not shown) for execution
by
microprocessor 138. Such flexibility in application installation increases the
functionality
of device 210 and may provide enhanced on-device functions, communication-
related
functions, or both. For example, secure communication applications may enable
electronic commerce functions and other such financial transactions to be
performed
using device 210.
[0056] In a data communication mode, a received signal such as a text message,
an e-
mail message, or web page download will be processed by communication
subsystem
111 and input to microprocessor 138. Microprocessor 138 will preferably
further process
the signal for output to display 122 and/or to auxiliary I/O device 128. A
user of device
210 may also compose data items, such as e-mail messages, for example, using
keyboard
132 in conjunction with display 122 and possibly auxiliary I/O device 128.
Keyboard 132
is preferably a complete alphanumeric keyboard and/or telephone-type keypad.
These
composed items may be transmitted over a communication network through
communication subsystem 111 or short range communication subsystem 141.
[0057] For voice communications, the overall operation of device 210 is
substantially
similar, except that the received signals would be output to speaker 134 and
signals for
transmission would be generated by microphone 136. Alternative voice or audio
I/O
subsystems, such as a voice message recording subsystem, may also be
implemented on
device 210. Although voice or audio signal output is preferably accomplished
primarily
through speaker 134, display 122 may also be used to provide an indication of
the
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identity of a calling party, duration of a voice call, or other voice call
related information,
as some examples.
[0058] Serial port 131 in FIG. 11 is normally implemented in a personal
digital
assistant ("PDA")-type communication device for which synchronization with a
user's
desktop computer is a desirable, albeit optional, component. Serial port 131
enables a
user to set preferences through an external device or software application and
extends the
capabilities of device 210 by providing for information or software downloads
to device
210 other than through a wireless communication network. The alternate
download path
may, for example, be used to load an encryption key onto device 210 through a
direct and
thus reliable and trusted connection to thereby provide secure device
communication.
[0059] Short-range communications subsystem 141 of FIG. 11 is an additional
optional component which provides for communication between device 210 and
different
systems or devices, which need not necessarily be similar devices. For
example,
subsystem 141 may include an infrared device and associated circuits and
components, or
a BluetoothTM communication module to provide for communication with similarly-
enabled systems and devices. BluetoothTM is a registered trademark of
Bluetooth SIG,
Inc.
[0060] FIG. 12 is a block diagram illustrating a memory 201 of the wireless
device
210 of FIG. 11 in accordance with an embodiment of the application. The memory
201
has various software components for controlling device 210. Memory 201 may be
flash
memory 124, RAM 126 or a ROM (not shown), for example. In accordance with an
embodiment of the application, device 210 is intended to be a multi-tasking
wireless
communications device configured for sending and receiving data items and for
making
and receiving voice calls. To provide a user-friendly environment to control
the operation
of device 210, an operating system ("O/S") 202 resident on device 210 provides
a basic
set of operations for supporting various applications typically operable
through a
graphical user interface ("GUI") 204. For example, O/S 202 provides basic
input/output
system features to obtain input from Auxiliary I/O 108, keyboard 132 and the
like and for
facilitating output to the user. In accordance with an embodiment of the
application, there
CA 02527066 2005-11-15
are provided software modules 206 for wavetable instrument applications as
will be
described below. Though not shown, one or more applications for managing
communications or providing personal digital assistant like functions may also
be
included.
[0061] Thus, the wireless device 210 includes computer executable programmed
instructions for directing the device 210 to implement the embodiments of the
present
application. The programmed instructions may be embodied in one or more
software
modules 206 resident in the memory 201 of the wireless device 210.
Alternatively, the
programmed instructions may be embodied on a computer readable medium (such as
a
CD disk or floppy disk) which may be used for transporting the programmed
instructions
to the memory of the wireless device 210. Alternatively, the programmed
instructions
may be embedded in a computer-readable, signal-bearing medium that is uploaded
to a
network by a vendor or supplier of the programmed instructions, and this
signal-bearing
medium may be downloaded through an interface 111, 131, 141 to the wireless
device
210 from the network by end users or potential buyers.
[0062] The wireless device 210 has software modules for running client
software for
downloading wavetable data files. This software may be a standalone
application,
browser plugin, etc. Once the client determines which samples should be kept
in a
wavetable instrument based on the desired size of the wavetable data file, and
which
MIDI data will be used to play it, this information is sent to the proxy
server 100 as a
request to have the wavetable data file filtered and returned to the wireless
device 210.
[0063] The proxy server 100 runs wavetable data file filtering software. The
proxy
server 100 handles requests from wireless clients 210, downloads wavetable
data files
from the content server 250, and filters the downloaded wavetable data files
locally.
Typically, the proxy server 100 does not face the same memory and bandwidth
constraints that the mobile devices 210 do.
[0064] The content server 250 is a remote machine that provides access to pre-
created
wavetable data files.
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16
[0065] FIG. 3 includes flow charts illustrating operations 300, 400 of modules
within
a wireless device and proxy server system 210, 100, respectively, for
downloading
filtered wavetable content to the wireless devices 210 from the proxy server
system 210
in accordance with an embodiment of the application.
[0066] With respect to wireless device/client software modules, at step 310,
the
operations 300 start. A query message 301 is sent from the wireless device 210
to the
proxy server 100 requesting a description of the required wavetable data file.
In response,
a description message 302 is received from the proxy server 100. This
description, or
metadata, typically contains information pertaining to the instruments) in the
file and
details with respect to the size, notes, etc., of the samples in the wavetable
instrument(s).
[0067] At step 320, if there is more than one wavetable instrument in the data
file,
then a choice is made as to which instruments in the wavetable data file
should be
contained in the filtered data file.
[0068] At step 330, the "instrument slot(s)" are chosen for the wavetable
instruments) that will be loaded into the wireless device's hardware or
software
synthesizer's memory. These correspond to a MIDI instrument program number
also
referred to as a "patch".
[0069] At step 340, a determination is made as to which MIDI files will be
used in
playing the wavetable instrument. This choice may be made automatically or by
a user.
These files are parsed to determine which notes will be triggered on which
program
numbers. If it is determined that the instruments that will potentially be
loaded into any of
the instrument slots(s) chosen at step 330 will not be triggered by the MIDI
files, then
this event may be reported to the calling application or user.
[0070] At step 350, using the information regarding the desired maximum size
of
each wavetable instrument, and the previously queried metadata, a
determination is made
as to how many samples each wavetable instrument will contain. This is
performed by
using the size of the largest sample in the instrument and calculating how
many samples
CA 02527066 2005-11-15
17
of that size can be included such that they are below the desired maximum
size. The
result is a good estimate, as in most cases all the samples within a source
wavetable
instrument will be approximately the same size. If there are significant
differences in the
sizes of samples contained in the source wavetable instrument, performing the
estimate as
if every sample is as large as the largest sample ensures that no
underestimate of the
combined size of the samples that will be chosen in the selection process of
step 360.
Underestimating could result in downloading a filtered wavetable instrument
that is
larger than the desired maximum.
[0071] At step 360, using the number of desired samples for each wavetable
instrument, and the set of MIDI notes that will be used to play the instrument
(see step
330 above), a determination is made as to which samples are to be filtered
out. The
filtering algorithm is described in more detail below.
[0072] At step 370, information regarding which instruments the returned
wavetable
data file is to contain and which samples these instruments are to include is
sent to the
proxy server 100 as a request to filter the wavetable data file message 303.
[0073] At step 380, operations 300 end with the return of filtered wavetable
data 304
from the proxy server 100.
[0074] With respect to the proxy server software modules, at step 410, the
operations
400 start. A request 301 is received from the wireless device for metadata.
[0075] At step 420, metadata is downloaded to the proxy server 100 from the
content
server 250. If there is no metadata to download, then the wavetable data file
is
downloaded to the proxy server 100 from the content server 250 and the
metadata is
extracted from it.
[0076] At step 430, the metadata 302 is sent to the client 210.
[0077] At step 440, a request 303 to filter a wavetable data file is received
by the
proxy server 100 from the client wireless device 210.
CA 02527066 2005-11-15
1g
[0078] At step 450, the wavetable data file obtained is filtered, if
necessary, and the
resulting filtered file 304 is sent to the client 210. As will be described
below, how this is
accomplished depends on the wavetable data file format that is to be filtered.
[0079] Two of the components of the Musical Instrument Digital Interface
("MIDI")
are the communications protocol (language) and a distribution format called
Standard
MIDI Files. The MIDI protocol is an entire music description language in
binary form.
Each word describing an action of musical performance is assigned a specific
binary
code. To sound a note in the MIDI protocol a "Note On" message is sent
followed by an
assigned "Velocity" which determines how loud the note will play. Other MIDI
messages include selecting which instrument to play, mixing and panning
sounds, and
controlling various aspects of electronic musical instruments.
[0080] When MIDI messages are stored on disk, they are commonly saved in the
Standard MIDI file format, which is slightly different from the native MIDI
protocol,
because the events are also time-stamped for playback in the proper sequence.
Music
delivered by MIDI files is the most common use of MIDI today. MIDI is the
primary
source of music in many popular PC games and CD-ROM entertainment titles, and
thousands of MIDI files are available on the Internet for recreational use.
Just about every
personal computer is now equipped to play Standard MIDI files.
[0081] One reason for the popularity of MIDI files is that, unlike digital
audio files
(e.g., .wav, .aiff, etc.) or even CDs or cassettes, a MIDI file does not need
to capture and
store actual sounds. Instead, the MIDI file can be just a list of events which
describe the
specific steps that a soundcard or other playback device must take to generate
certain
sounds. This way, MIDI files are very much smaller than digital audio files,
and the
events are also editable, allowing the music to be rearranged, edited, even
composed
interactively, if desired.
[0082] The Downloadable Sounds ("DLS") format allows MIDI files to be combined
with standardized samples of musical instruments, sound effects, or even
dialogue, to
recreate a copy of the sound intended by the composer. MIDI files with DLS are
one
CA 02527066 2005-11-15
19
solution for composers who want the predictable playback of digital audio, but
also need
the compactness and/or interactivity of Standard MIDI files for delivering
their music.
[0083] Originally targeted for CD-ROM and Internet entertainment applications,
DLS provides a means for game developers and composers to add their own custom
sounds to the General MIDI ("GM") sound set (e.g., a list of sound names or
"patches")
stored in a sound card's ROM. DLS-compatible devices generally download these
custom
sounds from card, disk or CD-ROM into system RAM, allowing MIDI music to be
freely
augmented with new instrument sounds, dialog or special effects thus providing
a
universal interactive playback experience, along with an enhanced palette of
sounds. At
the same time, it enables wavetable synthesizers in computer sound cards to
deliver
improved audio at no additional cost. The combination of MIDI messages
controlling
small sound samples, as opposed to the use of streaming digitized audio, makes
DLS
especially appropriate for interactive multimedia applications, and for
putting sound and
music on web pages where fast downloading, seamless playback, and user
interaction are
critical.
[0084] The DLS file format generally follows the standard Microsoft~ RIFF
layout
(with a form type of "DLS"), utilizing chunks and sub-chunks and incorporating
standard
WAVE files. The DLS file format is used to store both the digital sound data
and
articulation parameters needed to create one or more instruments. An
instrument contains
"regions" which point to WAVE files or samples also embedded in the DLS file.
Each
region specifies a MIDI note and velocity range which will trigger the
corresponding
sound and also contains articulation information such as envelopes and loop
points.
Articulation information can be specified for each individual region or for
the entire
instrument. The flexible file structure utilized by DLS means that a single
sample may
serve as different regions within different instruments. For example, a given
sample can
serve as region "lb" for instrument "1" while at the same time acting as
region "2a" for
instrument "2."
[0085] With respect to how the samples contained in a wavetable instrument
affect
the quality of audio playback, note that when creating wavetable instruments
any
CA 02527066 2005-11-15
transposing, or pitch shifting, used to reproduce tones for which there is no
corresponding
sample in the wavetable instrument's sample set will introduce some distortion
of the
timbres. Just how much distortion is determined by the number of samples
included in
the wavetable instrument, as well as the notes corresponding to those samples.
[0086] Multiple samples are included in a wavetable instrument so that the
entire
range of playable notes can be subdivided into subranges, known as
"keysplits". Each
keysplit region has an assigned sample which can be pitch shifted to reproduce
all notes
within the region. Having multiple keysplit regions and samples helps limit
distortion as
the pitch shifts required are not as large. That is, pitch shifting of a
particular sample is
limited to a specific range of notes. As an example of how the number of
samples affects
distortion, consider FIG. 4.
[0087] FIG. 4 is a block diagram illustrating a wavetable instrument 460
(e.g., a
piano) containing a single keysplit region 470 over a two octave range 480 in
accordance
with an embodiment of the application. The sample 490 for the keysplit region
470 is of a
sound that has the same pitch as the C note of the first octave. The further
away a
particular MIDI note X is from the C note of the sample 490, the more pitch
shifting that
will be required to play note X, and thus the more distorted it will be.
[0088] FIG. 5 is a block diagram illustrating a wavetable instrument 500
containing
two keysplit regions 510, 520 over a two octave range 530, 540 in accordance
with an
embodiment of the application. The sample 550 for region 1 510 is of a sound
that has the
same pitch as the C note of the first octave, and the sample 560 for region 2
520 is of a
sound that has the same pitch as the D note of the first octave. Since there
is more than
one sample that can be shifted, the sample whose note is closest to the MIDI
note X that
is to be played can be pitch shifted, thus reducing the distortion when
playing certain
notes. That is, the notes starting from D in the first octave and above will
all be less
distorted when played on the wavetable instrument 500 of FIG. 5 than when
played on
the wavetable instrument 460 of FIG. 4.
CA 02527066 2005-11-15
21
[0089] As an example of how the notes of the samples affect distortion,
compare the
wavetable instrument illustrated in FIG. 5 with the one illustrated in FIG. 6.
[0090] FIG. 6 is a block diagram illustrating a wavetable instrument 600
containing
two keysplit regions 610, 620 over a two octave range 630, 640 in accordance
with an
embodiment of the application. In FIG. 6, the keysplit regions 610, 620 and
samples 650,
660 are distributed evenly over the range 630, 640. The wavetable instrument
600 of FIG.
6 is arranged so that the amount of pitch shifting required in playing the C
note of the
second octave is reduced. In fact, the largest pitch shift required to play
any of the notes
is 6 semitones compared to a largest pitch shift of 21 semitones for the
wavetable
instrument 500 of FIG. 5.
[0091] Thus, to build a wavetable instrument for playing any note, a good
distribution
of keysplit regions with samples includes an even distribution. However, if it
is known
that a wavetable instrument will be used to play a specific set of notes, it
can be further
optimized. In the following, a method for determining an optimized set of
keysplits and
samples for playback of a particular set of notes and a method of adapting
this optimized
set to fit the content contained in a pre-existing wavetable instrument will
be described.
These methods allow for the filtering out of the M samples that are least
helpful with
respect to playback quality.
[0092] In accordance with an embodiment of the application, a method for
determining which samples to discard in order to reduce the size of wavetable
instruments will now be described. If a choice is made to reduce the size of
the wavetable
instrument by discarding some of the samples it contains, then playback
quality may also
be reduced because, as mentioned above, having more samples will result in
less
distorted playback. Since this reduces the effectiveness of one of the methods
used to
reduce distortion, close attention must be paid to the other method of
reducing distortion
as described above (i.e., the notes of the samples or the positioning of the
samples
throughout the note range) when choosing which samples to discard.
CA 02527066 2005-11-15
22
[0093] Having a wavetable instrument, a set of notes that will be played using
the
wavetable instrument, and knowing the number N of samples to be contained in
the
resulting wavetable instrument, creating an optimal balance of size and detail
includes the
following steps. First, a determination is made as to the preferred N keysplit
regions and
associated preferred samples that the resulting wavetable instrument should
contain in
order to have the highest quality playback of the set of notes that will be
used to drive the
wavetable instrument. By preferred samples it is meant the samples that would
be desired
if a sample of every note was available to choose from. Second, an adjustment
is made to
the preferred model to fit the samples contained in the wavetable instrument
to be
filtered. Typically, the available samples will not contain a sample for every
corresponding MIDI note.
[0094] With respect to the first step of determining the preferred N keysplit
regions
and associated preferred samples the resulting wavetable instrument should
contain,
excluding the trivial cases where N = 1 (i.e., the resulting wavetable
instrument would
contain one keysplit region that spans the lowest of the MIDI notes through
the highest,
with the preferred sample being at the midpoint note of the range) and where N
>_ # of
MIDI notes that will be played using the wavetable instrument (i.e., the
resulting
wavetable instrument would have a keysplit region and corresponding preferred
sample
for every note), the method of determining the preferred splits and samples
includes the
following steps.
[0095] First, the largest gaps between consecutive MIDI notes is found. For
example,
if the list of notes contains MIDI note 60 (middle C) and MIDI note 63 (D#)
without
having notes 61 or 62 in the list, then the gap between them is of magnitude
2. By finding
the largest gaps, it can be determined whether or not the set of MIDI notes
should be
subdivided into subsets, up to a maximum of N subsets, where each subset would
be
made its own keysplit region and would have its own sample, or whether evenly
divided
keysplits and evenly distributed samples should be created.
[0096] A gap is sufficiently large so that it should be subdivided when the
magnitude
of the gap is greater than half the distance spanned by the range of MIDI
notes to the left
CA 02527066 2005-11-15
23
of the gap, or greater than half the distance spanned by the range of MIDI
notes to the
right of the gap. This is so because in these cases, dividing and isolating
into subsets and
assigning samples to each subset would result in the MIDI notes being closer
to a sample
than they would be had a even distribution been chosen. For example, compare
the
wavetable instruments shown in FIGS. 7 and 8.
[0097] FIG. 7 is a block diagram illustrating a wavetable instrument 700
containing
two keysplit regions 710, 720 having ranges 730, 740 that span the notes
starting at the D
note of the first octave through the A note of the second octave in accordance
with an
embodiment of the application. The keysplit regions 710, 720 and samples 750,
760 are
distributed evenly over the ranges 730, 740. FIG. 8 is a block diagram
illustrating a
wavetable instrument 800 containing two keyplit regions 810, 820 having ranges
830,
840 that span two disjoint subsets of notes starting at the D note of the
first octave
through the A note of the second octave in accordance with an embodiment of
the
application. The grey shaded keys 770, 870 represent notes that are contained
in the
desired list of MIDI notes.
[0098] The N largest gaps can be checked, and if each gap is large enough, the
MIDI
notes to the left of the gap can be isolated from those to the right of the
gap. This will in
essence provide a method to create keysplit regions. That is, those to the
left of the gap
will be contained in their own keysplit region, as will those to the right of
the gap. If at
each iteration it is determined that the largest gap is within a keysplit
region created in
one of the previous iterations, that keysplit region can also be subdivided
into two new
keysplit regions. At this point, specific samples for these keysplit regions
are not being
chosen. Rather, a sample is being granted to each region. This basically means
that the
value of a "pending sample count" variable for each region is being set to 1.
This is done
because, in the following step, any remaining samples will be granted to some
of the
regions, and how many samples a region has will affect which samples are
chosen.
[0099] If N is greater than the number of keysplit regions created in the
previous step,
then it will be repeatedly determined which of the keysplit regions should be
granted an
additional sample (i.e., a "pending sample count" variable for that region
will be
CA 02527066 2005-11-15
24
incremented) until there are no more samples left to grant. At each iteration,
a sample is
granted to the region with the largest distance between an endpoint note and
the nearest
sample note if the region's "pending sample count" number of samples have
already been
distributed evenly.
[0100] Once the granting of all of the samples is completed, the regions with
more
than one sample granted to them will be subdivided evenly. Once the final set
of keysplit
regions is obtained, the preferred sample note for each region will be the
region's
midpoint note.
[0101] In addition, an initialization phase can be used to perform tasks such
as
arranging the input MIDI data and source wavetable data into data structures
that can be
used to access information quickly. For example, a data structure can be used
to maintain
information regarding the distance between consecutive MIDI notes (gaps).
[0102] Also, in the event of there being two or more gaps of the same
magnitude, a
tie breaker algorithm may be used to determine which of those gaps is the one
to be
processed next. An example may be to assign a greater priority to the gap that
is
contained in the region that has the most notes.
[0103] With respect to the second step of adjusting the preferred model to fit
the
samples contained in a wavetable instrument to be filtered, having knowledge
of what
samples are in the source wavetable instrument to be filtered, the preferred
model
calculated using the method described above can be adjusted to fit the samples
available
in the source wavetable instrument. This is performed by realigning the
preferred keysplit
regions and samples in order to derive a wavetable instrument that is the best
quality
given the source wavetable content that is available. Once the preferred model
is
adjusted, so that the finalized keysplit regions and samples are selected, the
samples that
are remaining are implicitly filtered out. The method of adjusting the
preferred model
involves the following steps.
CA 02527066 2005-11-15
[0104] First, the list of samples to be chosen from is narrowed. It can be
known ahead
of time whether some samples will never be chosen in the sample selection
process. This
is particularly true for samples whose note values are significantly less than
the lowest
note in the range of MIDI notes that will be used to play the wavetable
instrument, and
those whose note values are significantly higher. Choosing which samples
should be
included in the selection process can be performed as follows. If there are no
samples
within the MIDI note range, there are at most two samples that will be
selected from,
namely, the closest sample to the left of the range (if any) and the closest
sample to the
right (if any). If there are samples within the MIDI note range, it may still
be desirable to
include with them some samples from outside of the range in the selection
process. To
find out which of those outside the range should be included, the left most
and right most
samples within the range are found. The distance from the left end of the
range to the
leftmost sample within the range, minus one, is how far to the left of the
note range that
will be included in the search for samples. The same operation is performed
with respect
to the right side.
[0105] Second, new samples for each of the preferred keysplit regions are
selected.
This is performed as follows. Until all regions have been processed, find the
region that
will have to be skewed/adjusted the most. That is, the region that has the
longest distance
between the preferred sample and the closest of the two nearest samples to the
right and
the left of the preferred sample. Then, set the sample for this range to be
the closer of the
two samples on either side. If one end of the range is closer to the sample
that was not
chosen than to the sample that was chosen, mark the region as a potential
"split-region".
That is, add the region to a split-region list. After all of the regions have
been adjusted, it
will then be determined from the list of split-regions whether any of them
should be split
into their own region.
[0106] Third, if a split of some regions is to be performed, then an
associated join
will have to be performed as well. If two regions have already been adjusted
and have
chosen the same sample, then that can be considered as a join. If a join is
already in hand,
CA 02527066 2005-11-15
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the worst of the split-regions can be split, the worst being the one that has
an endnote that
is furthest away from the note of the chosen sample.
[0107] If no joins are in hand, a different operation is required. The effect
of the split
has to be evaluated to determine whether it is wise to make the split. This is
performed by
determining how far away the end of the range which is closest to the sample
"x" that
was chosen previously is from the sample "y" of the next region beside it.
That is, the
region that will be potentially joined. If the distance is greater than or
equal to the
distance between the other end of the range and the sample "z" that is closest
to that end,
then the split is not required. If it is less than that distance, that endnote
and its adjacent
notes whose distance is also less can join the region for sample "y". The rest
can join the
region for sample "z".
[0108] Thus, in accordance with embodiments of the application, before a
wireless
device client 210 downloads a wavetable instrument contained in a data file
residing on a
content server 250, a limit can be determined for how large the wavetable
instrument is to
be in order to fit the resources available. Or, a user can choose to set a
predefined limit.
After requesting metadata regarding the contents of the wavetable data file,
using the
limit, a determination can be made as to the maximum number of samples N
contained in
the wavetable instrument that can be downloaded to the wireless device while
still having
a combined size that is under the limit. Given this information, and having a
set of MIDI
files that will be used as instructions to play the wavetable instrument
(i.e., the set of
MIDI files can be specified by a user or application), it can be determined
which N
sampled notes contained in the wavetable instrument are the best ones to keep
in the
wavetable instrument when it is downloaded. By best, it is meant that they are
the best N
samples that, when used for playback of those particular MIDI instructions,
will result in
the highest quality or least distorted playback. The information regarding
which samples
are desired for the wavetable instrument are sent to a proxy server 100 as a
request to
filter out any extra samples from the wavetable instrument other than the
desired samples.
The proxy server 100 downloads the unmodified wavetable data file from the
content
CA 02527066 2005-11-15
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server 250, filters it locally, and then returns the resulting file to the
wireless device client
210.
[0109] Using the same algorithm to choose the best samples, it can also be
determined which would be the M best samples to delete from an already
downloaded
wavetable instrument. This is advantageous when more flash is required in the
wireless
device 210 for incoming messages, calendar appointments, etc.
[0110] The above described methods may be summarized with the aid of
flowcharts.
FIG. 9 is a flow chart illustrating operations 900 of modules within the
wireless
communications system for determining keysplit regions and associated samples
for a
wavetable instrument in accordance with an embodiment of the application.
[0111] At step 1-1, the operations 900 start. A determination is made as to
whether
the wavetable to be downloaded has more than one sample.
[0112] At step 1-2, if the wavetable does not have more than one sample then
no
filtering is required and the operations 900 end.
[0113] At step 1-3, if the wavetable does have more than one sample, then an
initialization operation (see above) is performed.
[0114] At step 1-5, a determination is made as to whether the number of
desired
samples is equal to one.
[0115] At set 1-4, if the number of desired samples does equal one, then the
preferred
wavetable has one region spanning the MIDI note range with the preferred
sample being
at the midpoint of the range. Operations then proceed to step 2.
[0116] At step 1-6 , if the number of desired samples is not equal to one,
then a
determination is made as to whether the number of desired samples is greater
than or
equal to the number of MIDI notes.
CA 02527066 2005-11-15
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[0117] At step 1-7, if the number of desired samples is greater than or equal
to the
number of MIDI notes, then the preferred wavetable has a keysplit region and
corresponding preferred sample note for every MIDI note. Operations then
proceed to
step 2.
[0118] At step 1-8, if the number of desired samples is less than the number
of MIDI
notes, then a determination is made as to whether all the samples have been
granted.
[0119] At step 1-9, if all the samples have been granted, then the preferred
regions
are committed and operations proceed to step 2.
[0120] At step 1-10, if all the samples have not been granted, then a
determination is
made as to whether all the gaps have been processed. If all the gaps have not
been
processed, then the largest unprocessed gap is processed and operations
proceed to step
1-12.
[0121] At step 1-11, if all the gaps have been processed then the sample is
granted to
the region with the largest distance between an endpoint note and the nearest
sample note
if the region's "pending sample count" number of samples were to have been
distributed
evenly.
[0122] At step 1-12, a determination is made as to whether there is a tie with
respect
to the largest gap. If there is no tie, operations proceed to step 1-14.
[0123] At step 1-13, if there is a tie with respect to the largest gap, a
tiebreaker
mechanism (see above) is used to choose which gap should be processed next.
[0124] At step 1-14, a determination is made as to whether the gap is large
enough to
be subdivided. If not, operations return to step 1-10.
[0125] At step 1-15, if the gap is large enough to be subdivided, then a
determination
is made as to whether the gap is contained in a region created in a previous
step.
CA 02527066 2005-11-15
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[0126] At step 1-16, if the gap is contained in a region created in a previous
step,
then the container region is subdivided and operations return to step 1-8.
[0127] At step 1-17, if the gap is not contained in a region created in a
previous step,
then one keysplit region is created spanning all notes to the left of the gap
and one
keysplit region is created spanning all notes to the right of the gap.
Operations then return
to step 1-8.
[0128] At step 2, operations end when the preferred model is adjusted to fit
samples
contained in the wavetable to be filtered (see FIG. 10).
[0129] FIG. 10 is a flow chart illustrating operations 1000 of modules within
the
wireless communications system for adjusting the keysplit regions and
associated
samples in accordance with an embodiment of the application.
[0130] At step 2-1, the operations 1000 start. The list of samples contained
in the
wavetable to be chosen from is narrowed.
[0131] At step 2-2, a determination is made as to whether all regions have
been
processed. If all regions have not been processed, the region that has to be
skewed the
most is processed and operations proceed to step 2-3. If all regions have been
processed,
then operations proceed to step 2-8 described below.
[0132] At step 2-3, a sample is chosen for the region that has to be skewed
the most.
[0133] At step 2-4, a determination is made as to whether a sample chosen for
the
present region has been chosen for another region. If not, then operations
proceed to step
2-6.
[0134] At step 2-5, if a sample chosen for the present region has been chosen
for
another region, then the "joins in-hand" count is incremented and operations
proceed to
step 2-6.
CA 02527066 2005-11-15
[0135] At step 2-6, a determination is made as to whether one end of the
region range
is closer to a sample that was not chosen. If not, then operations return to
step 2-2.
[0136] At step 2-7, if one end of the region range is closer to a sample that
was not
chosen, then the region is marked as a "split-region" and operations return to
step 2-2.
[0137] At step 2-8, a determination is made as to whether all "split-regions"
have
been processed. If not, the worst of the unprocessed split regions is
processed and
operations proceed to step 2-10.
[0138] At step 2-9, if all the "split-regions" have been processed then the
filtering
process is complete and the operations end.
[0139] At step 2-10, a determination is made as to whether there are any
"joins in-
hand" remaining. If so, then operations proceed to step 2-11. If not, then
operations
proceed to step 2-12.
[0140] At step 2-11, a determination is made as to whether the unchosen sample
that
is closest to part of the region range is already the chosen sample of another
range. If not,
then operations proceed to step 2-13. If so, then operations proceed to step 2-
12.
[0141] At step 2-12, a determination is made as to whether it is worthwhile to
have
part of the range moved to a different existing region. If so, then operations
proceed to
step 2-14. If not, then operations return to step 2-8.
[0142] At step 2-13, proceeding from step 2-11, the region is split so that
the part of
the range that was closer to a sample other than the chosen sample becomes its
own
region whose sample is the closer sample. Operations then proceed to step 2-
15.
[0143] At step 2-14, proceeding from step 2-12, the region is split so that
the part of
the range that was closer to a sample other than the chosen sample becomes
part of the
region owning that sample. Operations then return to step 2-8.
CA 02527066 2005-11-15
31
[0144] At step 2-15, proceeding from step 2-13, the "joins in-hand" count is
decremented. Operations then proceed to step 2-8.
[0145] The above described methods for selecting samples for the wavetable
instrument are generally performed by the wireless device 210. However,
according to an
alternate embodiment of the application, one or more of these methods can be
performed
by the proxy server 100. In this embodiment, the wireless device 210 provides
information pertaining to its available memory to the proxy server 100.
[0146] While this application is primarily discussed as a method, a person of
ordinary
skill in the art will understand that the apparatus discussed above with
reference to a
communications system, a proxy server, a content server, and a wireless
device, may be
programmed to enable the practice of the method of the application. Moreover,
an article
of manufacture for use with a communications system, such as a pre-recorded
storage
device or other similar computer readable medium including program
instructions
recorded thereon, may direct the communications system to facilitate the
practice of the
method of the application. It is understood that such apparatus and articles
of
manufacture also come within the scope of the application.
[0147] The embodiments of the application described above are intended to be
examples only. Those of skill in the art may effect alterations, modifications
and
variations to the particular embodiments without departing from the scope of
the
application. The subject matter described herein in the recited claims intends
to cover
and embrace all suitable changes in technology.
[0148] A portion of the disclosure of this patent document contains material
which is
subject to copyright protection. The copyright owner has no objection to the
reproduction
by any one of the patent document or patent disclosure, as it appears in the
Patent and
Trademark Office patent file or records, but otherwise reserves all copyrights
whatsoever.
