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1 of 6 )

United States Patent

6,897,868

Cliff

May 24, 2005

Visual representation of audio content

Abstract

Audio content on a compact disc is displayed as an image of a rotating vinyl
record, thus enabling a disc jockey to obtain a visual indication of the nature
of the content on the disc. The apparatus comprises a manually operable joystick
which can be used to operate a compact disc player, and to cause it to play the
content on the basis of the viewed image of the vinyl record, thus simulating
the complete (including the visual aspect of the content recorded on a vinyl
disc) functional capability of a traditional record deck and vinyl record in a
compact disc player.

Inventors:

Cliff;
David Trevor (Bristol, GB)

Assignee:

Hewlett-Packard
Development Company, L.P. (Houston, TX)

Appl. No.:

09/949,932

Filed:

September 12, 2001

Foreign Application Priority Data

Sep 20, 2000 [GB]

0023046

Current U.S. Class:

345/440 ; 345/15; 345/440.1;
345/440.2

Current International Class:

G11B 27/10 (20060101); G10H
1/00 (20060101); G11B 31/00 (20060101); G11B
27/00 (20060101); G11B 27/34 (20060101); G09T 011/00 ();
G09T 011/20 (); G09G 005/22 (); G09G 005/24 ()

Field of Search:

345/440,440.1,440.2,15

References Cited [Referenced
By]

U.S. Patent Documents

5227892

July 1993

Lince

5467288

November 1995

Fasciano et al.

5601436

February 1997

Sudman et al.

5682326

October 1997

Klingler et al.

6335730

January 2002

Gould

6466211

October 2002

Havre et al.

6507349

January 2003

Balassanian

6563523

May 2003

Suchocki et al.

6665751

December 2003

Chen et al.

2001/0047384

November 2001

Croy

Foreign Patent Documents

2235815

Mar., 1991

GB

WO 91/03053

Mar., 1991

WO

WO 91/13497

Sep., 1991

WO

WO 97/01168

Jan., 1997

WO

Other References

http:/www.plmsc.psu.edu/.about.www/matsc597/vectors/curvilinear/note4.html.
* .
Pages 81 and 285 Merriam Webster's Collegiate Dictionary tenth
edition.* .
Walker, Martin "Steinberg Wavelab 3.0", Sound On Sound vol.
15, Issue 5, 03/00 (Cambridge, UK), pp 102-106. .
White, Paul "TC Works
Spark 1.5", Sound On Sound vol. 15, Issue 5, 03/00 (Cambridge, UK), pp
206-210. .
Search Report for Corresponding United Kingdom Patent
Application No. GB 0023046.6..

Primary
Examiner: Brier; Jeffery
Assistant Examiner: Amini; Javid

Claims

What is claimed is:

1. A method of varying playback speed of
musical content on an audio player which generates an audio playback signal from
a recording medium storing the content, comprising the steps of: generating a
visual representation of variation in at least one parameter of the content with
time on a curvilinear axis in the image of a grooved disc record, signifying an
instantaneous value of the parameter on the axis with a cursor, and
synchronizing temporal progression of the instantaneous value of the parameter
with the audio playback signal; intervening in the synchronized temporal
progression by moving the cursor and curvilinear axis relative to each other;
and operating the audio player to generate an audio playback signal
corresponding to relative motion of the cursor and axis resulting from the
intervention.

2. A method according to claim 1 wherein in the visual
representation of the parameter, temporal progression is signified by moving the
curvilinear axis relative to the cursor.

3. A method according to claim
1 wherein the image of the record has an appearance substantially the same as a
genuine vinyl record on which the musical content is recorded.

4. A
method according to claim 3 wherein the audio player is a CD player, and the
visual representation is an image of a grooved vinyl disc record.

5. A
method according to claim 4 wherein the image of the vinyl record rotates
relative to the cursor.

6. A method according to claim 5 wherein the
cursor is an image of a stylus on the vinyl record.

7. DJ apparatus
comprising: an audio player which generates an audio playback signal from a
recording medium storing musical content; a processor connected to the audio
player, and adapted to: read the content and generate a visual representation of
variation in at least one parameter of the content with time on a curvilinear
axis in the image of a grooved disc record; signify an instantaneous value of
the parameter on the axis with a cursor; and synchronize temporal progression of
the instantaneous value of the parameter with the audio playback signal; a
visual monitor connected to the processor, and on which the visual
representation, including the cursor, is displayed; a manual actuator, connected
to the processor, and which enables a user manually to override relative motion
of the cursor and curvilinear axis during the aforesaid synchronized temporal
progression; wherein the processor is additionally adapted, upon actuation of
the actuator, to operate the audio player to generate an audio playback signal
corresponding to instantaneous relative motion of the cursor and axis.

8. Apparatus according to claim 7 wherein in the visual representation,
the curvilinear axis rotates relative to the cursor.

9. Apparatus
according to claim 8 wherein the cursor is an image of a stylus.

10.
Apparatus according to claim 7 wherein the audio player is a CD player, and the
content is stored on a CD.

11. Apparatus according to claim 7 comprising
scanning means for scanning the CD at a speed higher than the audio playback
signal, in order to obtain data to generate the visual representation in advance
of the audio playback signal.

12. Apparatus according to claim 11
wherein the scanning means is provided by the audio player operable in a high
speed mode.

13. A method of visually representing musical content stored
on a recording medium and output as an audio playback signal from an audio
player, comprising the steps of: generating a visual representation of variation
in at least one parameter of the content with time on a curvilinear axis in the
image of a grooved disc record; signifying an instantaneous value of the
parameter on the axis with a cursor; and synchronizing temporal progression of
the instantaneous value of the parameter with the audio playback signal.

14. A method according to claim 13 wherein the image of the record
rotates relative to the cursor.

15. A method according to claim 14
wherein the image of the record has an appearance substantially similar to a
vinyl record on which the content is recorded.

16. A method according to
claim 13 further comprising the steps of: intervening in the aforesaid
synchronized temporal progression by moving the cursor and curvilinear axis
relative to each other, and operating the audio player to generate an audio
playback signal corresponding to the relative motion of the cursor and axis.

Description

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates, inter alia, to the visual representation
of audio content, such as music, which when recorded on one or more types of
data storage medium gives no visual indication to the naked eye of the nature of
the content thus recorded. One example of the use of the present invention is
the display of audio content recorded on a compact disc and which represents
recorded music, in the visual form that the same or corresponding content would
have to the naked eye when recorded on a traditional vinyl disc.

2.
Description of Related Art

Currently, in spite of the widespread
adoption of digitally recorded audio material in the form of compact discs, and
more recently in the form of MP3 digital audio files, the vast majority of disc
jockeys ("DJ's") use conventional vinyl records, played on special arrangements
of record "turntables" or "decks". The arrangement of record decks typically
involves having two turntables, so that the DJ can cue up a track on one record
while the other is playing, or can mix music from a track on one record into the
music from a track on the other record. Typically mixing will include playing
music from one track over another (for example as one piece of music fades and
the other starts) to provide a seamless transition from one track to another, or
"scratching" during which the DJ rapidly moves one of the turntables back and
forth over a short distance, causing the stylus of the turntable to move
correspondingly back and forth within the spiral groove on the record, to create
a characteristic sound. The reliance on the use of traditional vinyl discs and
record decks is anomalous given the lower cost of recording on more modern media
such as compact discs, and accordingly attempts have been made to provide
special compact disc players, known as "CD decks" which aim to provide the DJ
with the same capability as conventional record decks. For example CD decks
include a large "jog wheel", which effectively provides manual control of the CD
turntable to enable scratching. Notwithstanding this however, the use of CD
decks remains low.

SUMMARY OF THE INVENTION

One aspect of the
present invention lies in an appreciation of a functional capability provided to
the DJ by a traditional vinyl record which is not available with existing CD
decks. The majority of existing record decks for DJ's include a "target light"
or "cue lamp" provided in respect of each turntable on the deck, and this allows
a DJ to see the radial position of the stylus (which is useful for cueing up a
track on the record). However, because the target lamp typically has a high
angle of incidence to the record (i.e. subtends a small angle with respect to
the surface of the record), it has the effect of illuminating the top surface
and interior edges of the spiral groove on the vinyl record. Because different
frequencies and amplitudes of recorded sound give rise to differing groove
patterns having differing reflectances, the light reflected from a particular
part of the record will be indicative of the nature of the audio content
recorded on the vinyl at that location. This effect is enhanced once the record
is rotating, because repetitive elements (such as drum beats or bass lines)
reveal themselves as periodic variations in the groove's reflectance pattern. It
is thus possible for a DJ to see a visual representation of the nature of the
audio content stored on the record, which in turn enables the DJ to position the
stylus by placing the stylus at an appropriate point on the record.

A
further aspect of the present invention provides an apparatus for substantially
replicating this functional capability so that audio content recorded on a first
type of data storage medium which gives no visual indication to the naked eye of
the nature of the content is visually represented in a useful manner.

Accordingly, an aspect of the present invention provides DJ apparatus
comprising: an audio player which generates an audio playback signal from a
recording medium storing musical content; a processor connected to the audio
player, and adapted to: read the content and generate a visual representation of
variation in at least one parameter of the content with time on a curvilinear
time axis; signify an instantaneous value of the parameter on the time axis with
a cursor; and synchronise temporal progression of the instantaneous value of the
parameter with the audio playback signal; a visual monitor connected to the
processor, and on which the visual representation, including the cursor, is
displayed; a manual actuator, connected to the processor, and which enables a
user manually to override relative motion of the cursor and time axis during the
aforesaid synchronised temporal progression; wherein the processor is
additionally adapted, upon actuation of the actuator, to operate the audio
player to generate an audio playback signal corresponding to instantaneous
relative motion of the cursor and time axis.

The use of a curvilinear
axis enables extremely efficient use of image space so that it is possible to
display to a user, at any given moment, a visual representation of a much larger
amount of content than would otherwise be the case. Preferably the visual
representation is an image of a vinyl record, with the at least one parameter
being at least frequency, and more preferably amplitude (which therefore
implicitly includes frequency information). The image of the record is,
according to the best mode of the invention, substantially the same as the
appearance of a vinyl record on which the content is recorded, and so would be
familiar to users of traditional record decks.

Typically, the content
will be stored for playback in a digital audio format, having been originally
recorded from an analogue audio signal, and will enable the use of standard
digital data storage (such as compact discs) and data readers (such as a CD
player) to produce the audio playback signal. The apparatus of the present
invention will thus provide the user with the visual display capability of a
traditional analogue record deck, enabling manual intervention in the playback
via the actuator, and using visual feedback from the map.

The invention
may be applied equally to provide this capability in conjunction with other
audio content storage media, such as magnetic tapes (irrespective of whether an
audio signal is recorded as analogue or digital data) to provide the user with a
real time visual indication of the nature of the audio content recorded thereon.

A further aspect of the present invention provides a method of varying
playback speed of musical content on an audio player which generates an audio
playback signal from a recording medium storing the content, comprising the
steps of: generating a visual representation of variation in at least one
parameter of the content with time on a curvilinear axis, signifying an
instantaneous value of the parameter on the time axis with a cursor, and
synchronising temporal progression of the instantaneous value of the parameter
with the audio playback signal; intervening in the synchronised temporal
progression by moving the cursor and curvilinear time axis relative to each
other; and operating the audio player to generate an audio playback signal
corresponding to relative motion of the cursor and time axis resulting from the
intervention.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments of
the invention will now be described, by way of example, and with reference to
the accompanying drawings, in which:

FIG. 1 is a schematic illustration
of a first form of apparatus embodying aspects of the present invention;

FIG. 2 is a schematic illustration of a further form of apparatus
embodying aspects of the present invention.

DESCRIPTION OF PREFERRED
EMBODIMENTS

Referring now to FIG. 1, a digital storage medium (DSD) 10,
such as a compact disc, has digital audio content, typically music, stored
thereon, which is readable by means of a reader 12. The reader 12 is connected,
via a switch node 14 to a digital-to-analogue converter (DAC) 16 and a processor
unit 18. The processor unit 18 controls the operation of, inter alia the reader
12, the DAC 16 and the switch node 14 in dependence upon input signals from a
user console 20, i.e. in order to give effect to instructions input at the
console by a user, requiring that audio content on a particular storage medium
is output as an audio playback signal to a listener, or mapped (an explanation
of which follows). Content on the storage medium is therefore read by the reader
12 in response to an instruction from the processor 18 following a suitable
input instruction from a user. Upon receipt of a user instruction requiring the
audio playback of the content, the processor 18 actuates the reader 12 to read
the audio content from the storage medium 10, and switches the output of the
reader 12, via switch node 14 to the DAC 16. The output node 22 of the DAC is
typically connected via an adjustable signal amplifier 24 (the gain of which is
adjustable at the console 20 to provide volume control) to one or more audio
transducers such as a loud speaker 26. The "play" functional capability of the
system is thus in effect identical to that of a standard audio CD player, with
the reader 12, the processor 18, and the DAC 16 combining to perform this
function. Upon receipt of an instruction from the console 20 to map the audio
content on the storage medium, the processor 18 actuates the reader 12 and
switch node 14 to read the audio content from the storage medium 10 and to
transmit the audio content to the processor 18. The processor then analyses the
audio content, and, by means of suitable software, compiles a visual
representation, here having the form of a map 40, which in the present
embodiment is a series of amplitude values of the audio content with respect to
time. It is not necessary to use amplitude, and any suitable parameter may be
used to create the visual representation, such as frequency. Amplitude is
however preferred because it implicitly includes frequency information. This map
40 is then stored by the processor in a random access memory (RAM) 28. Upon
receipt of an appropriate command from the console 20 the processor 18 is able
to retrieve the map from the RAM 28 to generate an image of the map 40 upon a
monitor 30. In the example of FIG. 1 the visual image of the map 40 is simply a
graph 42 showing the variation in the amplitude of the audio content stored in
the storage medium 10 with respect to time.

Once audio content from the
storage medium has been mapped, the map image 42 is automatically generated on
the monitor 30 whenever a "play" command is received at the processor 18 from
the console 20. In such a situation the processor 18 switches audio content from
the reader 12 through the DAC 16 to create an audio playback signal, and then to
the output terminal 22, and thus the loud speaker 26. However, in contrast to
the simple "play" operation described above, the audio content is initially
switched to the DAC 16 via the processor 18. This process enables the processor
18 to display a cursor on the map image 42, whose instantaneous position on the
image is synchronised with the audio playback signal coming out of the loud
speaker 26. In the present example the cursor is simply an arrow 32 relative to
which the graph of amplitude against time moves, to indicate the amplitude of
the audio signal at any given moment T in time.

Providing a map image
which moves relative to the cursor requires more processing capability, but this
has the advantage of being able to display large data map images without having
to refresh the image on the monitor, as would be required with a static map
image.

By monitoring the position of the cursor on the map, a DJ is
given an indication of, for example, when the beat of the music changes, or
whether the music is louder or softer without listening to the music. This
enables a DJ for example to locate a particular type of music on the storage
medium rapidly, which is frequently necessary for example so that the DJ can
synchronise two pieces of music. In one embodiment of the system described a
further piece of music can be played on a second duplicate system of the system
thus far described, although this has the disadvantage of requiring two readers,
DACs etc. In a further embodiment the RAM 28 is sufficiently large to store a
map of the audio content from a storage medium and a copy of the audio content
itself. The audio content from the RAM may be "played" (i.e. switched through
the DAC 16 by the processor to generate an audio signal by the processor 18) and
mapped in response to appropriate commands from the console 20 is the same way
as described above. Thus to the user, the functional capability of the system is
identical to that of two separate systems once the audio content to be stored in
the RAM 28 has been mapped.

In a further modification of the system
described thus far, a manual actuator is provided, here having the form of a
joystick 50. The joystick 50 is connected to the processor 18, and enables a DJ
to intervene manually with the audio player (whether this is a traditional
player or a "player" in which an audio signal is generated from audio content
stored in the RAM). By moving the joystick the DJ can alter the position of the
cursor 32 on the map 40, and the processor is programmed to access and play the
audio content at the instantaneous cursor position. The cursor 32 may thus be
said to operate as a "virtual stylus".

The reader 12 of the various
embodiments described in connection with FIG. 1 is preferably a high speed
reader, i.e. it operates at a faster speed than is necessary in order to
retrieve the audio content from the storage medium and convert the audio content
to an audio playback signal to play the audio signal at its intended speed. This
enables rapid mapping of audio content, while still permitting the audio content
to be read at standard speed (i.e. the speed necessary in order to generate a
playback signal for playing at its intended speed), either by means of direct
control of the reader from the processor 18, or by the use of buffers, for
example. However it would be possible nonetheless to use standard speed data
readers, although the audio content would ideally have to be mapped in advance
and the use of the virtual stylus to control the player is then only possible in
respect of audio content stored in the RAM.

Referring now to FIG. 2,
wherein like elements are depicted with the same reference numerals, a high
speed reader 12 is operable by the processor 18 in the manner previously
described to read and store audio content on storage medium DSD2 in RAM 28. In
this example an audio playback signal generated from audio content DSD1, stored
on the storage medium 10 is playing at loud speaker 26, while the audio signal
generated from audio content on DSD2 is playing in headphones 126. The monitor
shows an image of the map of the audio content on DSD2, but the content on both
DSD1 and DSD2 have been mapped, and selection of which map is to be displayed at
any instant is possible via the console 20, as well as the selection of a split
screen mode in which both map images are visible. The map images in this
embodiment have the form of virtual vinyl records on which the audio content on
DSD1, DSD2 is recorded; the cursor is depicted as a stylus 132 moving across the
surface of the vinyl record disc. The position of the stylus image on either of
the virtual vinyl records in adjustable using the joystick 50, with selection of
the map in respect of which the joystick is operable being possible via the
console 20. In a preferred embodiment the joystick 50 is integrated into the
console 20 for ease of use.

The processor is thus controllable from the
console 20 to move the cursor 132 to a particular position on an image of what
the audio content would look like in the event that it had been recorded on a
vinyl record disc (the medium most favoured by current DJ's), in order to play
the audio signal corresponding to the audio content at the new cursor position.
The volume of either output channel may be faded out etc. in the same way as
with existing systems in order to mix audio playback signals generated from
audio content on storage media DSD1 and DSD2.

* * * * *