Abstract:
The present invention relates to a method of a video and audio data signal processing with a display apparatus for a visual communication systems. The display apparatus is coupled to a universal serial bus (USB) hub root and a host equipped with a communication interface. A digital camera and a memory are coupled to a digital signal processor (DSP). The digital video data signal generated from the digital camera is stored in the memory and directly processed in the DSP. A USB hub system receives the video data signal with parallel and transmits the video data signal to the host with serial by a USB protocol. The USB hub system also receives the audio data signal with serial and transmits the audio data signal to the DSP with parallel. In the display apparatus for the visual communication systems, the DSP receives the digital video data signal acquired from the digital camera and directly processes the digital video data signal. Therefore, the display apparatus executes the visual communication with more clear video data signal by a simple connection and a noise exclusion. The display apparatus also avoids overlapping data conversion devices such as sound controller and image capture device in these video and audio data signals transmission with the host.

Description:
CLAIM OF PRIORITY 
     This application makes reference to, incorporates the same herein, and claims all benefits accruing under 35 U.S.C §119 from an application entitled  Display Apparatus For Visual Communication  earlier filed in the Korean Industrial Property Office on Dec. 1, 1997, and there duly assigned Ser. No. 97-65103 by that Office. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates to a display apparatus for a visual communication system, and more particularly to the display apparatus for visual communication system which includes a digital signal processor(DSP) for digital video data signal and analog audio signal processing and sends the resultant data to a host through a universal serial bus (USB) hub interface. 
     BACKGROUND OF THE INVENTION 
     Referring to FIGS. 1 and 2, a conventional computer system for a visual communication is illustrated. In this computer system, a monitor  20  is connected to a host (computer)  10  via universal serial bus (USB) cable  22  and the keyboard  70 , mouse  60 , microphone  50 , speakers  40  and  42  and camera  30  are all connected to host  10  via respective cables. An analog video signal acquired from an analog camera  30  is converted into digital video data and is composed of an international standard form video data signal for the visual communication by an image capture device  15  included in host  10 . The analog audio signal acquired from microphone  50  is also composed of an international standard form audio signal for the visual communication by a sound controller  14  included in the host  10 . These video and audio signals are compressed and decompressed for visual communication and transmitted through a communication interface unit  16 , such as a modem. The computer system converts these analog video and audio signals into these digital video and audio data by these analog-to-digital converting devices such as the sound controller  14  and the image capture device  15  included in the system, and converts received digital and audio data to corresponding analog signals for output via display unit  20  and speakers  40  and  42 , respectively. Since the system has overlapping these data conversion devices, cost and data loss are increasing in the several process of data conversion. Furthermore, since the system has complex connecting lines between peripheral devices and the host unit  10  in the analog data transmission processing, the system has much noise in the data signal. 
     Examples of a display apparatus for a visual communication system which includes universal serial bus (USB) architecture are provided by U.S. Pat. No. 5,797,028 to Dale E. Gulick et al. entitled  Computer System Having An Improved Digital And Analog Configuration , and U.S. Pat. No. 5,818,948 to Dale E. Gulick entitled  Architecture for A Universal Serial-Based Speaker Controller.    
     SUMMARY OF THE INVENTION 
     It is therefore an object of the present invention to solve the above mentioned problems and to provide a display apparatus for a visual communication system which is capable of direct processing of these digital video and audio data signals. 
     It is another object of the invention to solve the above mentioned problems and to provide a display apparatus for the visual communication system which is capable of providing of these digital video and audio data signals through a USB system. 
     In order to attain the above objects, according to an aspect of the present invention, there is provided a digital camera for generating a digital video data signal, a memory for storing the digital video data signal and a digital signal processor(DSP) for controlling the digital camera operation and a read/write operation of the memory while controlling the digital video data signal transference between the memory and the host. 
     According to another aspect of this invention, there is provided a USB control unit for controlling the digital video data signal transmission between the host and the DSP through at least one USB hub port. 
     In the display apparatus for the visual communication system according to the invention, the DSP receives directly the digital video data signal acquired from the digital camera and the audio data signal acquired from a microphone through the USB hub. 
     Furthermore, in the display apparatus, the DSP transfers these video and audio data signals to the host through the USB hub system with a parallel or serial format, which data signals are converted by an A/D converter and a D/A converter. 
     An advantage of this invention is that it avoids overlapping data conversion devices such as a sound controller and an image capture device and avoids complex connection between the host and these peripheral devices. 
     Further advantage of this invention is that it executes the visual communication with clearer data directly by the DSP through the USB hub. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     A more complete appreciation of the present invention, and many of the attendant advantages thereof, will become readily apparent as the same becomes better understood by reference to the following detailed description when considered in conjunction with the accompanying drawings in which like reference symbols indicate the same or similar components, wherein: 
     FIG. 1 is a perspective view illustrating a conventional computer system for general visual communication; 
     FIG. 2 is a block diagram illustrating details of the computer system of FIG. 1; 
     FIG. 3 is a block diagram illustrating an envisioned computer system for general visual communication; 
     FIG. 4 is a perspective view illustrating a computer system including a display apparatus for visual communication systems according to the present invention; 
     FIG. 5 is a block diagram illustrating a configuration of the computer system shown in FIG. 4; 
     FIG. 6 is a block diagram illustrating a configuration of a display apparatus according to the present invention shown in FIG. 4; 
     FIG. 7 is a block diagram illustrating a configuration of a DSP shown in FIG. 6; 
     FIG. 8 is a block diagram illustrating a configuration of a USB control unit shown in FIG. 6; and 
     FIG. 9 is a flowchart illustrating a processing of DSP shown in FIG.  6 . 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     An envisioned computer system for visual communication is illustrated in FIG.  3 . This computer system uses a universal serial bus (USB) in the data processing for solving the complex connecting line problems in the computer system in FIG.  1 . In this computer system, as shown in FIG. 3, the digital video data signal is transferred from a camera  120  coupled to a monitor  170  to the host  180  through USB ports DC 2  and DP 1  (downstream port), the keyboard is coupled to monitor  170  via USB ports DC 3  and DP 2  and the mouse is coupled to monitor  170  via USB ports DC 4  and DP 3 . The host  180  carries out the communication with the above mechanisms via ports RH 1  (a USB root hub) and UP 1  (upstream port). A telephone is connected to host  180  via ports RH 2  and DC 1  The system still has a noise problem because the microphone  160  and a speaker unit  150  for transmitting and receiving the analog audio signals are connected with the host  180  through audio input/output terminals CN 1  and CN 2  in the sound controller included in the host  180 . Since the audio signal is transmitted from the host  180  with an analog format, a realization of noise filtering and a sound effect function such as a stereo sound, a tone, a balance and so forth in the monitor  170  are difficult. 
     In FIG.  4  and FIG. 5, there is shown a visual communication system in accordance with the principles of the present invention. Referring FIG. 4, a host  100  is coupled to a monitor  200  through a USB cable  290  in the visual communication system. A keyboard  400 , a mouse  300 , a digital camera  500 , a microphone  600  and a speakers  700  and  701  are coupled to monitor  200 . 
     As shown in FIG. 5, the host  100  comprises two USB root hubs RH 1  and RH 2 . USB root hub RH 1  is coupled to an upstream port UP 1  included in the monitor  200 , and USB root hub RH 2  is coupled to a telephone via port DC 1 . Downstream ports DP 2  and DP 1  included in the monitor  200  are coupled to a USB mouse  300  and a USB keyboard  400  via the USB hub ports DC 2  and DC 3 . The USB hub included in the monitor  200  is a self-powered device, which can supply a power to these USB devices coupled to the USB hub such as the USB mouse  300  and the USB keyboard  400 . The digital camera  500 , the microphone  600  and the speakers  700  and  701  are directly connected to a DSP (denoted by the reference numeral  230  in FIG. 6) included in the monitor  200 . The monitor  200  executes the visual communication in a visual communication mode or executes an audio signal processing in a common mode in response to a control signal of the host  100 . The DSP  230  manages the audio data signal such as a tone, a balance, a volume and a stereo sound transmitted from the host  100  through the USB hub. 
     Referring FIG. 6, a detailed circuit configuration of the monitor  200  is illustrated. As shown in FIG. 6, a power supply unit  210  is included in the monitor  200  supplied a voltage via a power plug. The power supply unit  210  supplies a variety of voltages to the circuit of the monitor  200  and has a power management function for an electric power saving operation. The monitor  200  also comprises a video data signal processing unit  204 , a horizontal and vertical synchronizing signal processing unit  208 , a microcomputer  220  adapted to control these overall signals for operating the monitor  200 , and a cathode ray tube(CRT)  206 . The monitor further comprises the DSP  230  for the visual communication and the USB hub system  250  being equipped with the upstream port UP 1  and the downstream ports DP 1 , DP 2  and DP 3 . The digital camera  500  and a memory  260  are coupled to the DSP  230 . The microphone  600  and the speaker unit  700  and  701  are connected to the monitor  200  or may integrated into the housing of the monitor  200 . The operation of the above mentioned units are controlled by a programmed read only memory (ROM)  240 . ROM  240  may be located within DSP  230  or external DSP  230 . Similarly, DSP  230  may be a component of microcomputer  220 . The DSP  230  executes overall operations in the visual communication mode or the common mode by a program stored in ROM  240 . The digital camera  500  generates several clocks having a frame information for adjusting the video data signal or controlling several registers (not shown) included in the digital camera. The DSP  230  executes control operations for generating an international standard form video data signal or controlling an up/down moving operation and a left/right moving operation of the digital camera  500  by receiving of these clocks. The DSP  230  executes additional functions such as a zooming function and a focusing function of the digital camera  500 . The memory  260  receives an address and the control signal generated by the DSP  230  for a read/write operation of the video data signal and stores the digital video data signal generated by the digital camera  500 . For instance, the digital video data signal offered from the digital camera  500  is shaped into a common intermediate format (CIF), a quarter CIF (QCIF), or a sub-QCIF in accordance with a 4:2:0 video recording system (YUV system) format. The digital video data signal is sent to the DSP  230  with these clock signals containing the frame information of the digital camera  500 . The DSP  230  sends the address of the memory  260  and these control signals to the memory for writing the digital video data signal on the memory at a rate of 30 frames per second. The DSP  230  appoints an inner register for these zooming and focusing functions of the digital camera  500 . The DSP  230  also executes these control operations for these several operations of the digital camera  500 . In execution of the visual communication, the DSP  230  reads out the frame currently stored in the memory  260 . While the frame is being stored in the memory, the DSP  230  waits for the storing of the frame and reads out the stored frame to be completed. The microphone  600  sends the analog audio signal for the visual communication to the DSP  230 . The DSP  230  converts the digital audio data signal transmitted from the host  100  into the analog audio signal which is then sent to the speaker unit  700  and  701  through an amplifier  270 . The USB hub system comprises a USB control unit  250  and several hub ports such as the upstream port UP 1  and the downstream ports DP 1 , DP 2  and DP 3 . The USB hub control unit  250  is coupled to the DSP  230  with a parallel communication connection via parallel-serial/serial-parallel converter  256  for transferring these data and control signals. The USB hub control unit  250  executes control operations in response to these data and control signals via the hub ports and a root hub RH 1  included in the host  100 . The USB control unit  250  acquires an input data signal from the host  100  through the upstream port UP 1  and repeats the data signal to the downstream ports DP 1 , DP 2  and DP 3 . The UP 1  is upstream port receives the voltage and the data transmitted from the host  100  through the root hub RH 1 . The downstream ports DP 1 , DP 2  and DP 3  transfer the data and the voltages to the USB devices such as the keyboard  400 , the mouse  300  and a printer (not shown). The power supply unit  210  has an efficient power saving function and supplies a variety of voltages to the monitor  200  such as +80V, +150V, +24V, +12V and +5V. Especially, the voltage of +5V is the power of these downstream ports from DP 1  to DP 3  of the hub system included in the monitor  200 . 
     FIG. 7 illustrates a detailed configuration of the DSP  230  included in the display apparatus for the general visual communication according to the present invention. The DSP  230  operates by the program stored in the ROM  240 . As shown in FIG. 7, the DSP  230  comprises a DSP CORE  232 , a general I/O port  234 , an A/D converter  236  and a D/A converter  238 . The detailed circuit of the DSP  230  executes the video and audio data signal processing by the control operation of the DSP CORE  232  through an internal bus included in the detailed circuit of the DSP  230  for transmitting these data and control signals. The DSP  230  also comprises an address generator ASIC  235  (which also may be an external component) for reading and writing the stored video data signal in the memory. For a time management of the memory reading out operation, the address generator ASIC  235  is located in between RAM  260  and the general I/O port  234  and generates the address ADDR 2  by the acquired control signal CONTROL 1  from the DSP CORE  232 . The DSP CORE  232  executes overall operations of the DSP by the program in the ROM  240 . The DSP CORE  232  executes the visual communication mode operation or common mode operation. The general I/O port  234  composes a video data signal transmitter (not shown) and an audio data signal transmitter (not shown). The video data signal transmitter transfers the video data signal from the RAM  260  to the USB control unit  250 . The audio data signal transmitter receives the audio data signal from the A/D converter  240  or the USB control unit  250 . The digital audio data signal acquired from the A/D converter  240  or the USB control unit  250  is adjusted from the sound effect function such as the stereo sound, the tone and the balance. The general I/O port  234  receives the audio data signal acquired from the microphone  600  and the video data signal read out from the memory  260  controlled by the DSP CORE  232  with parallel or transfers the audio data signal from the USB control unit  250  to the speaker unit  700  and  701 . The A/D converter  240  converts received the analog audio signal acquired from the microphone  600  into the digital audio data signal and transfers to the general I/O port  234 . In using the visual communication mode or a Noraebang mode, the A/D converter  240  converts the analog audio signal acquired from the microphone  600  into the digital audio data signal for transmitting to the host  100 . The host  100  transfers the international standard form video data signal for the visual communication through a communication interface unit such as a modem. In that case, the audio data signal for the visual communication is converted from the analog signal to the digital data signal through a data sampling process because the international standard form audio signal for the visual communication demands 16 bit resolution of the digital audio data signal. The D/A converter  242  converts the digital audio data signal which transferred from the host  100  through the USB control unit  250  into the analog audio signal and transfers to the amplifier  270 . The amplifier  270  transfers the analog audio signal to the speaker unit  700  and  701 . 
     Referring FIG. 8, the USB control unit  250  composes a hub controller  254 , a hub repeater  252  and a parallel-serial/serial-parallel converter  256 . The hub repeater  252 , the USB protocol control switch, is located in between the upstream port UP 1  and the downstream ports DP 1 , DP 2  and DP 3 . The hub repeater  252  has hardware supporting devices for transferring these signals between the ports. The hub controller  254  comprises an interface register (not shown). The interface register communicates with the host  100  in response to the control signal transferred from the DSP  230  or the host  100  for executing the visual communication mode operation or the common mode operation. Accordingly, the hub controller  254  controls data transmission between the host  100  and the DSP  230  through the interface register and manages a speed of data communication and power supplying of these USB devices coupled to the hub port DP 1 , DP 2  and DP 3 . The serial-parallel/parallel-serial converter  256  converts the serial format data input into the parallel format data output of these video and audio data signals transferred from the hub repeater  252 , or converts the parallel format data input into the serial format data output of these video and audio data signals transferred from the DSP  230  by the USB protocol. The flowchart of the processing of DSP  230  is illustrated in FIG.  9 . 
     Referring FIG. 9, in step S 900 , the DSP  230  begins initializing as the power is supplied to the monitor  200 . In step S 902 , the DSP  230  receives prescribed the control signal (CONTROL 4 ) from the host  100  to the general I/O port  234  via the USB control unit  250 . In step S 904 , the DSP  230  decides the operation of the visual communication mode or the common mode by the control signal (CONTROL 4 ). In other words, the DSP  230  considers executing of the visual communication or the audio data processing. In visual communication mode, the current step moves to step S 906 . In step S 906 , the DSP  230  controls the digital camera  500  and the memory  260  for the read/write operation of the video data signal and processes the audio data signal acquired from the microphone  600 . In step S 908 , the DSP  230  transfers these video and audio data signals with parallel to the USB control unit  250 . The USB control unit  250  converts the parallel data signal into the serial data signal and transfers these data signals to the host  100  by the USB protocol. The current step moves to step S 910  when the control signal (CONTROL 4 ) indicates the common mode in step S 904 . In step S 910 , the DSP  230  receives the audio data signal from the host  100  and executes the sound effect function in step S 912 . As mentioned above, the monitor  200  supplies these video and audio data signals to the host  100  through the USB hub system and executes the visual communication through the communication interface included in the host  100 . 
     While the invention has been particularly shown and described with reference to a preferred embodiment, it will be understood by those skilled in the art that modifications in detail may be made without departing from the spirit and scope of the invention.