Abstract:
A processor-based system may utilize a remote control unit which not only allows mouse input commands to be provided to the processor-based system but also includes a microphone and a speech engine for decoding spoken commands and providing code for presenting the commands to the processor-based unit. The processor-based system may provide information to the remote control unit about the vocabulary currently being used by applications active on the processor-based system. This allows the speech engine in the remote control unit to focus on a more limited vocabulary, increasing the accuracy of the speech recognition function and decreasing the capabilities necessary in the remote control unit based speech engine.

Description:
BACKGROUND 
     This invention relates generally to speech recognition and particularly to the control of computer software using spoken commands. 
     Currently available speech recognition software recognizes discrete spoken words or phonemes contained within words in order to identify spoken commands. The processing of the spoken commands is usually accomplished using what is known as a speech engine. Regardless of whether discrete terms or phonemes are utilized, the speech engine is called by the application program which needs the speech recognition service. 
     Operating systems may include Application Program Interface (API) software utilities which provide speech recognition. An application may incorporate a call to the speech API or the speech recognition may be supplied externally by a second application that intercepts the speech and feeds the first application simulated keys or commands based on the speech input information. 
     Speech recognition technology has been applied to controlling processor-based systems including desktop computer systems. A variety of different speech recognition software is available, some of which comes with a microphone which may be worn by the user. Apparently, the idea is that extraneous sounds around the system, such as the system cooling fan may disrupt the speech recognition quality. The microphone feeds into a sound port, usually on the back of the processor-based system. The use of the microphone allows the speech recognition engine to process the sounds less influenced by surrounding noise. 
     However, there is a continuing need for better ways to implement speech recognition services for processor-based systems. 
     SUMMARY 
     In accordance with one aspect, a processor-based system includes a first processor-based device having an airwave communication transceiver. A remote control unit has an airwave communication transceiver to communicate with the first processor-based device. The remote control unit includes a speech engine and a microphone coupled to the speech engine. 
     Other aspects are set forth in the accompanying detailed description and claims. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a front elevational view of a remotely controlled processor-based system; 
     FIG. 2 is a block diagram of a speech recognition system; 
     FIGS. 3-5 are flow diagrams for the speech recognition system shown in FIG. 1; 
     FIG. 6 is a schematic view of a computer display with two active windows; 
     FIG. 7 is a flow diagram of a program in accordance with one embodiment; and 
     FIG. 8 is a block diagram of a hardware system for use with the speech recognition system. 
    
    
     DETAILED DESCRIPTION 
     Referring to FIG. 1, a processor-based system  130 , illustrated as a set top computer system, includes a processor-based unit  110  which sits atop a television receiver  112 . The television receiver and the processor-based unit  110  may be controlled by a remote control unit  114 . The remote control unit may communicate through its own transceiver  118  with a transceiver  134  on the processor-based unit  110  and a transceiver  128  on the television receiver  112 . The communications between the remote control  114  unit and the television receiver/processor-based unit may use any of a variety of airwave communications including infrared, ultrasonic or radiowave signaling. 
     While the present invention has been illustrated in connection with a set top computer system, those skilled in the art will appreciate that the present application is also applicable to any of a variety of other processor-based systems including desktop computers, laptop computers and a variety of other processor-based appliances. 
     The remote control unit (RCU)  114  includes a microphone  126 . It also includes a cursor control system  116  which operates essentially like a mouse. The RCU  114  includes a mouse button  122  and a plurality of cursor direction control buttons  120 . Thus, the position of a cursor or highlighting on a screen  132  may be controlled by operating one of the four directional control buttons  120 . When the desired icon is indicated on the screen  132 , it may be selected by operating the button  122 . The remote control unit  114  may also include a numerical keypad  124 . 
     Referring to FIG. 2, a speech recognition system  11 , operating on the RCU  114 , works with an application software program  10 , running on the processor-based unit  110  which needs to respond to spoken commands. For example, the application  10  may be implemented through various graphical user interfaces or windows in association with the Windows® operating system. Those windows may call for user selection of various tasks or control inputs. The application  10  may respond either to spoken commands or tactile input commands. Tactile input commands may include pushing a keyboard key, touching a display screen, or mouse clicking on a visual interface, using the RCU  114 . 
     The application  10  communicates with a server  12 . In an object oriented programming language, the server  12  could be a container. In the illustrated embodiment, the server  12  communicates with the control  14  which could be an object or an ActiveX control, for example. The control  14  also communicates directly with the application  10 . 
     The server  12  can call the speech recognition engine  16 . At the same time, a driver  18  can provide input signals to the server  12  and the control  14 . Thus, in some embodiments, the control  14  can receive either spoken or tactile inputs (from the driver  18 ) and acts in response to each type of input command in essentially the same way. 
     Referring to FIG. 3, a program for recognizing speech may involve beginning an application (block  90 ) on the processor-based unit  110  that needs speech recognition services. The speech engine is provided with a vocabulary of command sets for an active screen or task, as indicated in block  92 . The command sets could be the vocabulary for each of the various applications that are implemented by the particular computer system or by a particular application program. The command set for the current application that is currently running is communicated to the server  12  or control  14  (block  94 ). Next, the speech is recognized and appropriate actions are taken, as indicated in block  96 . 
     Another implementation, shown in FIG. 4, also begins with starting an application, as indicated in block  98 . Speech units that need to be decoded are associated with identifiers (block  100 ). The identifiers may then be associated with a particular action to be taken in the application in response to the spoken command (block  102 ). Next, the flow determines the identifier for a particular spoken speech unit (block  104 ). The identifier is provided to a software object such as the control  14 , as indicated in block  106 . An event is fired when the object receives the command, as shown in block  108 . The event may be fired by the object whether the command is a result of a spoken command or a tactilely generated command. 
     Referring to FIG. 5, the application  10  passes a grammar table to the server  12  (block  20 ). In particular, the application initializes the grammar with speech identifiers associated. with each spoken command used in the application. These commands make up all of the command sets for a given engine. The grammar is a set of commands that may include alternative phrases. For example, a simple grammar could be (start/begin)(game X). This grammar would respond to the spoken commands “start game X” and “begin game X”. 
     The speech recognition engine  16  can operate on phonemes or with discrete terms. Thus, the application provides the particular command set (which is a subset of the engine&#39;s available commands) with the active application. This facilitates speech recognition because the speech recognition engine can be advised of the particular words (command set) that are likely to be used in the particular application that is running. Thus, the speech recognition engine only needs to match the spoken words with a smaller sub-vocabulary. For example, if the game x function was operating, only the command set of words associated with that application need be decoded. 
     In response, the server  12  initializes the speech engine  16  (block  22 ). The server  12  has a phrase and identifier table  36  as indicated in FIG.  2 . The application  10  also sends the speech identifiers associated with given spoken commands to the control  14  or server  12  (block  24 ). When the control  14  is activated in the container or server, the control may call the onControlInfoahanged method in the IOleControlSite interface, in an embodiment using ActiveX controls. This provides for transfer of information from the control  14  to the server  12  (block  26 ). The server in turn may call the GetControlInfo method from the IoleControl interface which allows communications from the server or container  12  to the control  14  (block  28 ). 
     The server uses the GetControlInfo method in the IOleControl interface and the OnMnemonic method in IOleControl to request identifiers from the control. The control may provide this information through IOleControlSite interface and the OnControlInfoChanged method, using ActiveX technology for example. 
     The server  12  enables the speech engine  16  (block  30 ), for any commands that are active, from the server&#39;s table  36 . The server uses the table  36  from the application to provide focus in particular applications. The control provides an effect comparable to that of an accelerator key. Namely, it provides a function that can be invoked from any window or frame reference. The application provides the speech identifiers and associates the identifiers with an actionby the control. 
     The server knows which vocabulary to use based on what task is running currently. In a system using windows this would correspond to the active screen. Thus, if the navigator is running, the server knows what the sub-vocabulary is that must be recognized by the speech engine. 
     When the server receives a speech message, it calls the speech API in the engine  16 . When a phrase is detected, the engine provides the phrase to the server for example, as a text message. The container does a table look-up (block  32 ). On a match between the phrase and the identifier, the server  12  may call the OnMnemonic method of the IOleControl interface, passing the identifier to the control. The control follows its preprogrammed rules and implements the corresponding action (block  34 ). The control may handle the message internally or send an event to the server. 
     As a simple example, a given screen may include two buttons, “ok” and “delete”. When the application comes up it sends the grammar for this screen to the server. For example, the grammar for “ok” might include “ok”, “right” and “correct”. 
     The application then associates “ok” with an identifier which corresponds to a particular control and does the same thing with “delete”. The identifier is simply a pointer or handle that is unique, within the application, to the particular command. The table  36  then includes the phrases “ok” and “delete”, an identifier for each phrase and an identifier for the control that handles the command. 
     When a control is instantiated, the application provides it with its identifier. The control is preprogrammed with the action it will take when the server advises the control that its identifier has been called. 
     When a speaker uses a word, the speech engine sends the word to the server. The server checks the phrases in its table  36  to see if the word is in its active list. In the simple example, if the word sent by the speech engine is not “ok” or “delete,” it is discarded. This would indicate a speech engine error. If there is a match between the word and the active vocabulary, the server sends the appropriate control identifier to the appropriate control, which then acts according to its programmed instructions. 
     A phoneme based speech engine with a large vocabulary can be used with high reliability because the engine is focused on a limited vocabulary at any given time. Advantageously this limited vocabulary may be less than 20 words in the table  36  at any given instance. 
     This frees the application from having to keep track of the active vocabulary. The application can tell the server which words to watch for at a given instance based on the active task&#39;s vocabulary. 
     There may also be a global vocabulary that is always available regardless of the active screen. For example, there may be a “Jump” command to switch screens or an “Off” command to terminate the active task. 
     Advantageously, the existing mnemonics or “hot keys” available in Microsoft Windows® may be used to implement speech recognition. For example, the OnMnemonic method may be given the new function of passing information from the server to the control corresponding to a spoken command. 
     While the methodology is described in connection with an ActiveX control, other object oriented programming technologies may be used as well including, for example, Javabeans and COM. In addition, still other such techniques may be developed in the future. 
     With embodiments of the present invention, an effect comparable to that of an accelerator key is provided. It gives a focus to the command with reference to a particular application. Therefore, speech can be used to focus between two operating tasks. For example, as shown in FIG. 6, if two windows A and B are open at the same time on the screen  76 , the command that is spoken can be recognized as being associated with one of the two active task windows or frames. Referring to FIG. 7, after a command is recognized (block  78 ), the application provides information about what is the primary, currently operating task and the speech may be associated with that particular task to provide focus (block  80 ). An input is then provided to one of the tasks (and not the other), as indicated at block  82 . The speech recognition is accomplished in a way which is effectively invisible to the application. To the application, it seems as though the operating system is effectively doing the speech recognition function. The synchronization is reduced. 
     The message which is passed to the ActiveX control from the container can include a field which allows the application to know if the command was speech generated. This may be useful, for example, when it is desired to given a spoken response to a spoken command. Otherwise, the application is basically oblivious to whether or not the command was speech generated or tactilely generated. 
     While the application loads the identifiers into the ActiveX controls (when they are instantiated), the controls and the container handle all of the speech recognition for the command words. The control and its container are responsible for managing when the words are valid and for sending appropriate messages to the application. Thus, the container or server does all the communication with the speech recognition API. The container may communicate with the ActiveX controls by standard interfaces such as IOleControl. As a result, the number of state errors that would otherwise occur if the application were forced to handle the speech recognition itself. 
     Referring next to FIG. 8, a hardware implementation for the embodiment shown in FIG. 1 includes a processor  150 . In one embodiment, the processor may be coupled to an accelerated graphics port (AGP) (see Accelerated Graphics Port Interface Specification, Rev. 1.0, published Jul. 31, 1996 by Intel Corporation, Santa Clara, Calif.) chipset  152  for implementing an accelerated graphics port embodiment. The chipset  152  communicates with the AGP port  154  and the graphics accelerator  156 . The television  112  may be coupled to the video output of the graphics accelerator  156 . The chipset  152  accommodates the system memory  158 . 
     The chipset  152  is also coupled to a bus  160 . The bus  160  couples a television tuner/capture card  162  which is coupled to an antenna  164  or other video input port, such as a cable input port, a satellite receiver/antenna or the like. The television tuner/capture card selects a desired television channel and also performs a video capture function. One exemplary video capture card is the ISVR-III Video Capture Card available from Intel Corporation. 
     The bus  160  is also coupled to a bridge  166  which may couple a storage device such as a hard disk drive  168  or a flash memory. The drive  168  may store the software  62  (FIG.  3 ). The bridge  166  is also coupled to another bus  170 . The bus  170  may in turn be coupled to a serial input/output (SIO) device  172 . The device  172  is coupled to an infrared interface  134 . Also connected to the bus  170  is a basic input/output system (BIOS)  174 . 
     The IR interface  134  may communicate using infrared signals with an IR interface  118  on the RCU  114 . Any of a variety of protocols may be utilized for implementing IR communications. In addition, other forms of airwave communications may be utilized as well. 
     The IR interface  118  on the RCU  114  communicates with a controller  150   a  which may be a processor such as a digital signal processor. The controller  150   a  communicates with the keypad  116  on the RCU  114  and the memory  158   a.  The controller  150   a  also receives spoken commands through the microphone  126 . The memory  158   a  may conveniently be implemented by a flash memory. The memory  158   a  stores the software  64  (FIG.  4 ),  66  (FIG. 5) and  68  (FIG. 7) for implementing the speech recognition features. 
     There are a number of advantages inherent in using the RCU  114  to implement speech recognition functions. First of all, by placing the microphone  126  in the RCU  114 , the speech capture may be achieved closer to the speech source. This may remove sources of ambient noise including those associated with the cooling fan or the processor-based unit  110 . 
     Moreover, by having speech recognition functions in the RCU  114 , the bandwidth of the communication path between the RCU  114  and the processor-based unit  110  may be diminished. Namely, by enabling an application running on the processor-based unit  110  to communicate information which allows a limited set of information to be utilized in the RCU  114 , the RCU may recognize the speech and provide a relatively limited bandwidth consuming input command over the infrared link to the processor-based unit  110 . Since the processor-based unit  110  can convey information to the RCU  114  about what command set to expect, a relatively small vocabulary speech engine may be implemented in the RCU  114  without requiring substantial processor capabilities. 
     For example, since the RCU  114  is battery-based, it is desirable to minimize the power usage in the RCU  114 . By implementing the system described above, for example using flash memory on the RCU  114 , a low power implementation may be operated. 
     While the present invention has been described with respect to a limited number of embodiments, those skilled in the art will appreciate numerous modifications and variations therefrom. It is intended that the appended claims cover all such modifications and variations as fall within the true spirit and scope of this present invention.