Patent Grant
7373587
1. Field of the Invention
The present invention relates to a method for broadcasting and viewing live events. In particular, the present invention utilizes computer simulation techniques to characterize the actions of a live event and broadcasts those computer characterizations to viewers who desire such information. The event is then simulated by the viewer's computer, utilizing the computer simulation characterizations of the actions of the event and known simulation techniques.
2. Related Art
The broadcasting of live events is well-known. Most commonly live events are broadcast as audio information or a combination of video and audio information utilizing either radio transmission techniques or television transmission techniques, respectively. There are limitations to both of these broadcasting techniques. Radio broadcasting provides no visual representation of the action being described. Video information of a television transmission is restricted by the angle of the television camera selected for transmission of a particular action within the event. In addition, unless the observer video tapes a television transmission or audio tapes a radio transmission, there is no possibility for replaying actions that occur within the event and there is no capability for the viewer to view or listen to only selected portions of the event, to review selected portions of the event, or to view the event at the viewer's leisure.
It is also well known to utilize computers to simulate activities. In particular, computer simulation techniques to represent the testing of the operation of devices is well known. Thus, computer programmers familiar with simulation techniques are familiar with programs required for simulating activities on a computer. However, such simulation techniques have not been utilized in conjunction with the broadcast of live events, which can be represented as a sequence of well-defined actions.
The present invention is directed to a method for broadcasting live events which overcomes the shortfalls of radio and television broadcasting. In particular, the present invention utilizes computer simulation techniques to characterize the actions of a live event, providing symbolic representations for the actions of the event rather than direct audio or visual signals. According to the method there is a broadcast of those characterizations. The live event can then be simulated at a remote location utilizing the characterizations or symbolic representations.
This broadcasting method has at least four advantages over other live broadcast techniques. First, the viewer may view the event at any time and may repeatedly view parts of the event. Secondly, the viewer can select a visual perspective for a given action within the event and can also choose to have information about the event displayed in graph or chart form rather than as visual images. Third, the user of the system is capable of monitoring a plurality of events simultaneously. Fourth, the method of the present invention results in using less bandwidth to broadcast a live event than is typically utilized for either radio or television broadcasts of such an event.
In a method according to the present invention, an event, is characterized as a sequence of sub-events constituted by a discrete number of actions selected from a finite set of action types which define the nature of the event. Each action is definable by its action type and from zero to possibly several parameters associated with that action type. The event may be observed by an observer who attends or watches the event and monitors each of the actions which occurs in the course of the event. The observer enters associated parameters for each action which takes place during the event. The event is thus represented by a sequence of sub-events each described by a sequence of characterizations of a plurality of actions in terms of parameters which are entered into an event file of a centralized data base computer which is accessible by the observer. The centralized data base computer may either be located at the site of the event or at a remote location and the information can be transmitted by the observer to the centralized data base computer. In either alternative, the observer, having access to a computer, encodes the event as a series of actions having associated therewith various parameters which define the actions that have taken place. Once the encoded description is transferred to an event file of the centralized data base computer, it is accessible by a viewer. Once accessed by a viewer these encoded descriptions of the actions of the event will then be utilized by the viewer's computer to reconstruct the actions of each sub-event of the selected event by using the parameter information associated with each action. The actions can be represented to the viewer either with visual images, audio images, or text, or some combination thereof.
The viewer will be able to select a perspective view for a visual image that is displayed on the display device associated with the viewer's computer. In addition, the viewer will be able to replay any portion of the event as already stored in an event file of a viewer data base at the viewer's computer. Furthermore, the viewer will be able to update the viewer computer data base with event information from the centralized data base computer at any time. In addition, the viewer's computer will be able to access the action information of a plurality of events from the centralized data base computer and store such information in a viewer file, permitting the viewer to select from any one of the plurality of events for view. The viewer will also be able to interrupt the display of the event on the viewer's computer at any time and return to any action within the event once it is stored in the viewer's computer data base.
One such typical event would be a sporting event such as a baseball game. It is also possible to utilize this system with such events as the activities involving a stock market, an election, an auction and any other event where a finite set of possible action types can be defined prior to the beginning of the event.
a) to 4(c) are illustrations of textual formats of messages sent by the observer's computer implementing the method of the present invention.
a) and 5(b) are flow charts for algorithms to run on an observer's computer and a centralized data base computer, respectively, in accordance with the method of the present invention.
a) and (b) are flow charts for an algorithm for the two-way communication illustrated in
a) and 9(b) illustrate a flow chart of algorithms for the one-way communication illustrated in
It is possible to have a plurality of observers 1 with computers 2 at a plurality of events with the encoded description of each event being transmitted by the associated observer and the observer's computer to the centralized data base computer 4. The viewer 7 may then select from the data base computer that event which is of interest, or can access all of the information with respect to all of the events and continue to update all events in the viewer's computer 6 while viewing only one event at a given time.
The encoded description of the event is written in a special-purpose computer language designed specifically for the purpose of describing events to be broadcast. The design and use of such special-purpose computer languages is well known to those skilled in the art of software development. The technique is discussed, for example in “Programming Pearls”, John Bentley, Communications of the ACM, August 1986, Vol. 29, No. 8, pp. 711-721). Bentley refers to such languages as “little languages”. At p. 711 of the article Bentley states:
Note that according to Bentley's definition, such a special-purpose language need not be a programming language used to define algorithms and computations. It may also be a means to describe something, as in the present invention, in which a special-purpose language is used to describe events.
In the present invention, the encoded description of the event includes an ordered sequence of sub-events. As constructed, each sub-event is identified by a number and the sub-event descriptor includes the number of that particular sub-event. In addition the sub-event descriptor identifies the start time of the sub-event and the end time in connection with the live event. Each sub-event descriptor also includes a set of one or more actions. Each action has associated therewith a tag indicating the begin and end times of the action, the type of action taking place, as well as values for parameters associated with the designated type of action. The types of actions and the parameters depend upon the nature of the real event.
The types of actions and the parameters depend upon the nature of the real event. That is, for any particular type of event, the practitioner of the present invention determines a set of types of actions and parameters that are appropriate to the type of event and to the degree of sophistication desired. Techniques for identifying the set of types of actions and parameters for any particular type of event are well known to those skilled in the art of special-purpose languages. For example, Bentley provides several guidelines (p. 720): “test your design by describing a wide variety of objects in the proposed language . . . iterate designs to add features as dictated by real use.” Of course, in the present invention, the sub-event sequence described above provides the general structure of the language design, so the practitioner need only identify the types of actions and parameters that will appear in the sub-event descriptions for the particular type of event. It will of course be possible to use the encoded description either to describe an entire sequence of sub-events of an entire event after it has ended or describe an initial subsequence of sub-events prior to the completion of the event. It will be possible with this encoding scheme to continuously update the data base file of the centralized data base computer with encoded descriptions of the event as it transpires, rather than waiting until the completion of the event.
Entering this encoded description by typing could be cumbersome depending on the number of actions involved in a subevent and the speed of the event being observed. Another possible technique for recording the event would be to use prompts generated by a special purpose software developed to assist the observer. The software provides a menu of possible action types and prompts an observer for relevant information about start and stop times and parameters after an action type is selected. A flow chart illustrating an algorithm for the special purpose software is set forth in
At step 301, the sub-event number SN is provided by the observer's computer. At step 302, the computer asks the observer for a start time (ST) for the sub-event identified as SN. At step 303, the computer asks the observer for an end time (ET) for the sub-event. An action number AN initially is set to “0” at step 304. The computer then asks the observer if there are any more actions occurring in this sub-event at decision step 305. If there are additional actions in this sub-event, then the action number AN is incremented by 1 at step 306 and the computer asks the observer for the identification of the action type AT. Once the action type AT is selected, the observer's computer, in step 308, retrieves the maximum number of parameters for actions of the type identified in step 307. The maximum number of parameters is identified as MAXPN. The parameter number PN then is set to 1 in step 309. Decision step 310 compares the parameter number PN to the value of MAXPN, the number of parameters for the given action type. So long as the maximum number of parameters has not been exceeded, the observer asks for a parameter value associated with the parameter number PN of action AT. This is step 311. After the observer enters the parameter value PVPN˜the parameter number PN is incremented by 1 in step 312 and the comparison decision of step 310 is carried out again. This loop continues until PN exceeds the MAXPN, the maximum number of parameters for the action type defined. Then decision step 310 jumps to step 313 at which time the computer asks the observer for the start time of action AN. In step 314, the computer asks the observer for the stop time of action AN. Then at step 315 the computer defines a sequence of characters, ADAN, as the sequence of characters representing the action, namely the start time, stop time, the action type and the parameter values associated with that action. The algorithm continues to step 305 in which a decision is made as to whether the observer has any additional actions to enter with regard to the sub-event. The loop of steps 305 to 315 continues until the observer has no additional actions to enter with regard to the identified sub-event. At this point, the characters for sub-event SN are set as the sub-event number, start and end times of the sub-event and the sequence of action descriptors in step 316.
It is also possible that the special user software could employ graphically-oriented techniques to additionally support the observer. For example, if a required parameter is the name of a participant in the event, the software prompts the observer with a complete list of participants and asks the observer to select one participant from the list. Furthermore, if a location is a parameter associated with an action, then the observer's computer may present a diagram of the site, and permit the observer, by use of a pointing device, such as a mouse, to point to the relevant location on the diagram to correspond to the parameter. Such prompting and pointing techniques in software are well-known.
Once the observer has constructed the encoded description of the sub-event, the description is sent to a centralized data base computer 4 as illustrated in
a) to 4(c) illustrate a textual format of messages from an observer's computer.
The centralized data base file 5 is able to store the sequences of sub-events for a plurality of different events as they are happening, simultaneously, by storing the information in separate files. Whenever information with regard to a particular event is received at the centralized computer data base, the file corresponding to that event is updated with the new sub-event information.
In
Once the centralized data base file has been updated by the observer or observers at various events, the event data descriptive of the sub-events constituting a particular event are maintained in the updated centralized data base file for access of a viewer or viewers.
There are two basic techniques for transmitting encoded descriptions from the centralized data base computer to a viewer's computer. The first technique utilizes a two-way communication technology such as standard telephone connection technology utilizing modems attached to the viewer's computer and the centralized data base computer. This two-way communication scheme is illustrated in
A flow chart illustrative of an algorithm for two-way communication is set forth in
The frequency of updates in the two-way communication scheme is controlled, not only in response to the updating by observers, but also by the frequency with which the viewer accesses the centralized data base computer. In the two-way communication scheme the viewer can request updates continually or at irregular intervals or even wait until the event is over and then access the information by requesting it from the centralized computer data base.
A second technique by which a viewer may access material regarding an event or have the viewer's computer data base updated utilizes a one-way broadcast technology such as radio, television or microwave, either through the air or through a cable. This technique is illustrated in
The frequency of updating in the one-way communication scheme is determined by the frequency with which the centralized data base computer broadcasts encoded sequences. This frequency, in turn, depends upon the amount of information in the event descriptions and on the bandwidth of the broadcast technique. Even when the same broadcast channel is used for multiple simultaneous real events, the viewer's computer is typically updated within a few seconds of when the data base computer is updated by communication from the observer's computer.
a) and 9(b) are flow charts illustrative of algorithms for the centralized data base computer and viewer's computer, respectively, for implementing a one-way communication.
At step 901, the centralized data base computer defines the maximum number of events being observed and broadcast as a value MAXEI and then, in step 902 of
The viewer's computer waits for the next event file to be received, as indicated at step 910 of
Regardless of the choice of algorithms for communication between the data base computer and the viewer, i.e., either one way or two-way communication, the algorithms expressed in the flow charts
The viewer's computer, regardless of the manner in which it receives information from the centralized data base computer, displays the encoded sequence of sub-events associated with a particular event by using techniques derived from those used for discrete event simulation. As discussed for example in SIMULATION MODELING AND ANALYSIS, Law et al.
Essentially, the viewer's computer performs at least two functions. First, it maintains a description of the status of the real event. Second, it shows each sub-event received from the centralized data base computer in either a graphical representation or a textual representation or an audio/visual representation.
The viewer's computer maintains a description of the status of the real event by using well-known techniques in the art of computer simulation and animation in discrete-event simulation. As discussed, for example, by Law et al.
The status of the real event is stored as the values of a set of status variables. One status variable is used to store a current simulated time. A specific set of remaining variables to be used for any particular event depends on the nature of the event and the degree of detail which is desired. For example, a sporting event might include status variables for the names of the players, the current score, and information about the current game situation. Software on a viewer's computer includes a routine for displaying status variables. Depending upon the degree of sophistication desired, this may be as simple as a textual table, showing all status variables and their values, or it can be as complex as a graphical diagram in which the values of some status variables are indicated by pictorial icons on a background image, which suggests a view of the real event.
The values of all of the status variables are maintained by a variant of a standard simulation algorithm in which the system state is updated for each “event” in an “event list,” in the temporal order in which the events occur. As described by Law et al. (pp. 6-8):
In the present invention, the simulation algorithm is applied to the actions of a sub-event. In particular, the “event list” of the Law et al. algorithm corresponds to the sequence of actions in the sub-event description, and a single “event” in the Law et al. algorithm corresponds to a single action. Note that the actions in the sub-event description are fixed for each sub-event, whereas the “event list” of the Law et al. algorithm is generated statistically during the simulation. In the present invention, there is also no need for the statistical counters or the report generator.
The “system state” of the Law et al. algorithm corresponds to the status variables of the present invention. Thus, the status variables are updated according to the actions of each sub-event, in the temporal order determined by the end times of the actions. In addition, since the status variables represent the state of the event, they are initialized at the beginning of the event, but not at the beginning of each sub-event. A further difference with the Law et al. algorithm is that the simulation algorithm of the present invention is combined with graphical animation techniques, as described below.
The viewer's computer displays an animation of each sub-event by using techniques derived from those used in computer-based animation. The basic principle is described, for example, by Kingslake (“An Introductory Course in Computer Graphics”, Richard Kingslake, Cartwell-Bratt, 1986): At page 93 of the textbook, Kingslake states: “When we watch a film it appears that the motion on the screen is smooth and continuous. However, if a piece of film is examined, it can be seen that it actually consists of a great number of individual pictures each one differing from the previous in only a very small way. The reason that, when projected, it appears to produce motion is because of a phenomenon known as persistence of vision. Any picture presented to the eye is retained for a short period of time. If another picture arrives during that period, then it appears to be a continuation of the previous one. If the new picture is slightly different from the first, then to the eye it appears that the picture has moved—hence: moving pictures.” Thus, in the present invention, each sub-event is animated by displaying a sequence of pictures, giving the viewer the illusion of physical actions and movements.
The sequence of pictures for a sub-event may be produced using any of the well-known computer-based animation techniques. For example, Burger et al. discuss the “sprite” technique, (“Interactive Computer Graphics,” Burget et al. Addison-Wesley, 1989, pp. 437-438),
In the present invention, the viewer's computer could show a background image, representative of the visual appearance of the setting in which the real event takes place, as well as sprites for each participant in the real event. The position and appearance of each sprite is updated as simulated time passes, according to the actions of the sub-event being displayed.
These two primary functions of the viewer's computer, namely, maintaining a description of the status of the real event, and displaying an animation of the real event, are performed by a single combined algorithm. The algorithm is applied to each sub-event in a sequence of sub-events which constitute the description of an event.
The algorithm used by the viewer's computer is based on standard discrete-event simulation algorithms (such as that shown by Law et al. in
In
In step 1108a decision is made as to whether there are any non-started actions that have a start time less than the designated time. If it is detected that there are no such actions, the time is incremented in step 1109 and the algorithm returns to the decision step of 1106. If there are any non-started actions detected at step 1108, one such action is identified in step 1110 and the action type and parameters of that action are identified in step 1111. The entries in the DISP, SOUN, TEXT and STAT tables corresponding to the action type are accessed and execution of DispA(PA), SounA(PA), and TextA(PA) will begin in step 1112.
The simulation of an entire event is accomplished by repeating the basic algorithm for simulating a sub-event as set forth in the flow chart of
By using the basic sub-event algorithm in a variety of different ways, the viewer's computer gives the viewer considerable flexibility. For instance, sub-events may be viewed from different perspectives by changing the background image and letting the entries in the display table depend upon the background image, as discussed above. In addition, any sequence of sub-events may be re-simulated at any later time by restoring the status of the event from the history table and executing the algorithm of
Just as the algorithms of the centralized data base computer will be best implemented utilizing a multi-processing technique, so will the algorithms associated with the viewer's computer be best implemented by using a multi-processing technique. As illustrated in schematic block diagram form in
The multi-processing techniques of
It will be possible to run the software for viewing the event on either a general purpose computer or a special purpose computer. The viewer computer may also take the form of a portable, or pocket-sized computer that will have the full functional capability of presenting the broadcasted live event as video images, audio images, or text or some combination thereof.
As an example to illustrate the broadcast method of the present invention, the application of the method to a half inning of a baseball game will now be described. The actions of the half inning are as follows:
Some of the action types that appear in this example are described below in Table I with their parameters:
A portion of the textual representation of the game is given below. The sub-events correspond to the first batter:
Game 14 2 8 True 2 3 8
. . . sub-events prior to beginning of ninth inning
{178 15:47:15 15:47:16
[0:00:00 0:00:01 Ball]}
{179 15:47:30 15:47:34
[O: 00: 00 O: 00: 03 GroundBall LeftInfield]
[O: 00: 01 0: 00: 04 RunToBase Batter FirstBase]
[O: 00: 03 0: 00: 03 FieldedBall Shortstop]
[O: 00: 03 0: 00: 04 ThrownBall Shortstop FirstBaseman]
[O: 00: 04 0: 00: 04 ForceOut FirstBase Batter FirstBaseman]}
“Game 1428” is the unique identifying code for this particular baseball game; “True” indicates that the game is still in progress; “238” indicates there have been 238 subevents so far. Sub-event 178 lasted only 1 second and consisted of a single action, namely, the pitcher throwing a ball. Subevent 179 lasted for 4 seconds, and consisted of 5 actions; the batter hitting the ball on the ground in the left infield toward the shortstop (3 seconds), the batter running toward first base (3 seconds), the shortstop fielding the ball (O seconds), the shortstop throwing the ball to the firstbaseman (1 second), and the batter being forced out at first base by the firstbaseman (O seconds).
As described above with respect to the algorithm in
For simulation on the viewer's computer, the status of the example baseball game consists of 11 status variables. These variables are given in Table II, along with an indication of how they could be displayed on the viewer's computer.
For example,
The last sub-event of the inning illustrates the use of the display, sound, and text tables. The sub-event would be represented textually as follows:
{196 15:53:30 15:53:40
[0:00:00 0:00:07 FlyBall DeepLeftOutfield]
[0:00:0 10:00:04 RunToBase Batter FirstBase]
[0:00:01 0:00:04 RunToBase FirstRunner SecondBase]
[0:00:04 0:00:07 RunToBase Batter SecondBase]
[0:00:04 0:00:07 RunToBase FirstRunner ThirdBase]
[0:00:07 0:00:07 CaughtFlyBall DeepLeftOutfield
LeftFielder]}
The tables for the relevant action types are as follows:
FlyBall (Location)
Disp: swing bat; move ball from home plate toward Location
Text: if Location is deep, then “it's a long fly ball, deep to Location . . .”
Soun: crack sound of wood on ball; if Location is deep, and batter is visitor, then gasp and silence
RunTowardBase (Runner, Base)
Disp: move Runner toward Base
Text: (no entry)
Soun: (no entry)
CaughtFlyBall (Fielder, Location)
Disp: move Fielder to Location, move ball to Location
Text: “caught by Fielder”
Soun: if Location is deep, and batter is visitor, then loud cheers
The present invention has been described in terms of basic algorithms and computer elements which can be utilized to carry out a broadcast of live events utilizing computer simulation techniques, where the techniques are familiar to those in the art.
The invention being thus described, it will be obvious that the same may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the invention, and all such modifications as would be obvious to one skilled in the art are intended to be included within the scope of the following claims.
This is a continuation of U.S. patent application Ser. No. 08/871,713, filed on Jun. 9, 1997, now U.S. Pat. No. 6,204,862, which is a continuation of U.S. patent application Ser. No. 08/660,891, filed on Jun. 10, 1996, now U.S. Pat. No. 5,671,347, which is a continuation of U.S. patent application Ser. No. 07/920,355, filed on Jul. 29, 1992, now U.S. Pat. No. 5,526,479, which is a continuation-in-part of U.S. patent application Ser. No. 07/542,990, filed on Jun. 25, 1990, now abandoned, and U.S. patent application Ser. No. 07/641,716, filed on Jan. 15, 1991, now U.S. Pat. No. 5,189,630.
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