JPH08149436A - Video phone - Google Patents

Abstract

(57) [Abstract] [Purpose] A television that allows you to easily adjust the position of your self-portrait on the screen, prevent screen burn-in, and make a natural call while viewing the image of the other party. Provide a telephone device. [Structure] When displaying a self-portrait on the screen of an external display device, the display control circuit 4 of the video display unit 4 is controlled by the CPU unit 7.
The reverse instruction is sent to 1. Next, the image data from the camera unit 1 is displayed on the external display device 20. In this case, since the inversion instruction is supplied, the video display unit 4 reads the temporarily stored image data in the reverse direction with respect to the horizontal direction, and then supplies it to the video processing unit 3. As a result, the above image data is left-right reversed. Next, the video processing unit 3
In the above, after converting the left-right reversed image data into a video signal of an analog signal, through the video circuit unit 2,
Send to an external display device. A self-portrait that is horizontally reversed is displayed on an external display device.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a videophone device, and more particularly to a compact and lightweight videophone device for transmitting color intermittent still images.

[0002]

2. Description of the Related Art In recent years, with the development of an advanced information society, demand for a communication medium for transmitting a large amount of various kinds of information at high speed has increased. To meet this demand, in 1988, as a TTC standard, JJ-40.10. , "Analog Telephone Band Still Image Communication System" was established. This makes it possible to send and receive monochrome still images to each other via an analog communication line. Then, in 1989, the TTC standard was revised so that not only black and white still images but also color still images can be sent and received. Videophone devices conforming to these TTC standards have been developed, and it is only possible to explain by voice. , It has the merit of being able to show and convey information that is difficult to convey to the other party, and it has been considered promising to spread.

Video telephone devices are roughly classified according to the communication network to be connected and the image and voice transmission systems. There are a black-and-white still image, a color still image, and a color moving image which are connected to the analog public line. A still image videophone device connected to such an analog public line to transmit a black and white still image employs a method of transmitting image data as it is without compressing it. For example, one screen is 100 × 160
When handling black and white image data of 64 gradations (6 bits) in pixels, 100 × 160 × 6 = 9600000 bits of data was transmitted at a transmission rate of about 8740 bps (8.4 Per Second), and thus one screen It took about 11 seconds to transmit minute image data. However, image data has a large amount of information, and it is not practical to process the image data as it is for purposes other than the storage type because of the memory capacity and communication speed.

Therefore, by compressing the image data and the audio data to be transmitted to, for example, about 1/20 to 1/100 and transmitting the data, the analog telephone band is utilized,
There is a moving picture television device that can transmit and receive color moving images of about 2 to 10 frames / second. Since the compressed transmission of image data transmits an extremely large amount of data, even if some transmission delay occurs, the influence on the progress of the call is not so large. Therefore, variable length coding (for example, CCITT Recommendation, H.261) is performed. Based variable length coding method) is generally used.

On the other hand, in compression transmission of voice data, the average generated bit length can be compressed by digitizing the voice data, but in general, entropy compression (for example, Huffman coding) in which the maximum bit length is not guaranteed is used. When applied to a signal, if a voice signal is generated with a long bit length due to entropy compression, a large transmission delay occurs in the voice signal, which has a large effect on the progress of the call, so it is encoded with a fixed bit length. Is being transmitted.

The videophone device connected to such an analog communication network has a communication function of multiplexing and transmitting image information and audio information, and corresponds to the connected communication network. The communication means, and the encoding of the image information and the audio information that are transmitted / received in addition to the communication signal based on the communication means are defined for each type of communication network by the ITU-T recommendation or the like.

[0007]

By the way, in the conventional videophone apparatus, when the self-portrait is displayed on the screen as it is,
Since the image of one's own image is displayed with left and right reversed, for example, when the face is moved to the right while trying to center the face on the screen, the image on the screen moves toward the left. For this reason, when trying to align the face with the center of the screen, it is difficult to align the face position.

Further, in the conventional videophone device, the received image data and the self-portrait are displayed on an external display device (CRT, L).
When it is displayed on a CD or the like, the video signal is output to the outside, but the video signal is continuously output unless the power is turned off. During this time, the image will continue to be displayed on the external display device and will not disappear, resulting in screen burn-in or
There was a problem that power consumption increased even when not making a call. If you turn off the power of the external display device, you can prevent screen burn-in.However, if you want to make a call or receive a call, you must turn on the power of the external display device. However, there is a problem that the operation becomes complicated.

Further, in the conventional videophone device, since the voice data and the image data are simultaneously transmitted immediately after the call is started, the image data is transmitted when the communication line having a low communication speed such as an analog public line is used. Since it takes time to send one sheet, only the voice is transmitted first,
There was a problem that it was an unnatural state in which only the sound could be heard before the image of the other party was displayed.

Therefore, according to the present invention, the position of the self-portrait on the screen can be easily adjusted by reversing the self-portrait horizontally, and the video signal is transmitted only when making a call or receiving a call. It is an object of the present invention to provide a videophone device capable of preventing image sticking on the screen of an external display device by outputting and making a call in a natural state while viewing the image of the other party.

[0011]

In order to achieve the above object, in the video telephone device according to the invention of claim 1, the screen of an external display device connected to the device is divided into a plurality of areas, and the plurality of areas are divided into a plurality of areas. It is characterized in that only an image displayed in a specific area among the areas is horizontally reversed. In the videophone device according to the invention of claim 2, at least a video capturing means for capturing a self-portrait of the user, a communication means for receiving a partner image of a partner transmitted via a communication line, and the video capturing. A horizontal reversing means for reversing the self-portrait captured by the means, and a display control for simultaneously displaying the partner image received by the communication means and the self-portrait reversed by the left-right reversing means on an external display device connected to the device. And means.

In a preferred aspect, for example, as described in claim 3, either one of the self-portrait captured by the video capturing means and the video supplied from the outside is displayed on the external display means. A display image switching means for selectively switching as a power image and supplying it to the left-right inverting means may be provided. Further, when the image supplied from the outside is selected by the display image switching unit, the left and right inverting unit displays the image on the external display unit without inverting the left and right. You may do it.

Further, for example, as described in claim 5, an operation means for instructing the left and right reversing means whether to display the image captured by the device in left and right inversion display or non-left and right inversion display is provided. You may Also, the image captured by the device is digital data stored in a predetermined storage means, for example, as described in claim 6, and the left / right reversing means is a horizontal direction of the image stored in the storage means. Alternatively, the reading may be performed in the opposite direction so that the image is horizontally reversed.

Further, in the video telephone apparatus according to the present invention, a video capturing means for capturing a video, a detecting means for detecting whether or not the telephone is in an off-hook state, and an off-hook state is detected by the detecting means. And a switching means for outputting the image captured by the image capturing means from the output terminal only when the image capturing means is operated. In a preferred aspect, for example, as described in claim 8, when the device is powered on, the switching means is turned on, and an opening message stored in advance is output from the output terminal for a predetermined time. You may make it provide a control means.

The video control means may send a black image to the output terminal prior to the switching operation of video output / non-output by the switching means. . Further, for example, the switching means may be a switch which is provided at the final stage of outputting the video signal and which is turned on / off based on the control signal from the detection means. Further, for example, as described in claim 11, an operation means for instructing to turn on the switching means and output an image from an output terminal is provided regardless of the detection of the off-hook state by the detection means. Good.

According to the twelfth aspect of the present invention, in the video telephone device, the communication means for exchanging video and audio through a communication line and the communication destination transmit and receive the video to and from the other party at the start of communication. And a communication control means for starting transmission / reception of voice by the communication means to / from the other party when transmission / reception of video for at least one screen is completed. Further, as a preferred aspect, the communication control means, when the transmission time required for transmitting and receiving one screen of video is constant as in claim 13, for example, when communication is started, the communication control means communicates with the other party. The image may be transmitted and received by the communication unit, and when the transmission time has elapsed, the communication unit may start transmitting and receiving the sound with the audio partner.

[0017]

In the present invention, the self-portrait captured by the image capturing means is horizontally inverted by the horizontal inversion means and then supplied to the display control means. Further, the partner image of the partner transmitted via the communication line is directly supplied to the display control means after being received by the receiving means. The display control unit simultaneously displays, on an external display device connected to the device, the partner image received by the reception unit and the self-portrait inverted by the left / right inversion unit. Therefore,
By reversing the image of one's own image, the position of the self-portrait on the screen can be easily adjusted.

Further, only when the off-hook state is detected by the detecting means, the switching means outputs the image captured by the image capturing means from the output terminal. Therefore, since the video signal is output to the outside only when making a call or when a call is received, it is possible to prevent burning.

Further, at the start of communication, video is transmitted and received to and from the other party by communication means, and when transmission and reception of at least one screen of image is completed, voice is transmitted and received to and from the other party by the communication means. It is controlled by the communication control means to start. Therefore, the voice is transmitted / received when the transmission / reception of the image is completely completed, so that it is possible to talk in a natural state while watching the image of the other party.

[0020]

Embodiments of the present invention will be described below with reference to the drawings. A. Configuration of Example A-1. Block Configuration of Videophone Device FIG. 1 is a block diagram showing the configuration of a videophone device according to an embodiment of the present invention. In the figure, the present video telephone device includes a camera unit 1, a video circuit unit 2, a video processing unit 3, a video display unit 4, an NCU unit 5, an audio processing unit 6, a CPU unit 7, a modem unit 8, a key / LED 9, and Remote control 10
And so on. The camera unit 1 captures the image of the user of the present videophone device and supplies it to the video circuit unit 2. As shown in FIG. 2, the camera unit 1 includes a lens 11, a CCD (Charge Coupled Device) 12, and a CC.
D driver 13, A / D / D / A converter 14, and D
It is composed of SP15. The lens 11 is an optical lens made of glass or plastic. CCD1
2 generates an electric signal based on the intensity of the light imaged by the lens 11, and the CCD driver 1 generates the electric signal.
It outputs by the drive signal from 3. CCD driver 13
Is an A / D / D / A converter 14 that amplifies the electric signal.
Supply to The A / D / D / A converter 14 is composed of an analog LSI having a filter or the like, converts the electric signal into a digital signal and supplies the digital signal to the DSP 15, and the digital signal subjected to color processing by the DSP 15. Is converted into an analog signal and supplied as a video signal to the video circuit unit 2 shown in FIG. The DSP 15 is for the above-mentioned color processing, and after performing the color processing on the digital signal, supplies it again to the A / D / D / A converter 14.

The video circuit section 2 is a discrete circuit such as a sync separation filter and the like. The video signal supplied from the camera section 1 and the video signal supplied from the external input terminal IN described above are supplied to a remote controller 10 which will be described later. The video processing section 3 is switched based on an instruction from
Supply to In addition, the video circuit unit 2 includes a video processing unit 3
The video signal (analog signal) supplied from the device is sent to the image output terminal OUT. The video circuit unit 2 is a CPU
An image output switch (not shown) that is turned on / off based on the control signal S1 from the unit 7 is provided, and the image output switch controls the image output to the image output terminal OUT.

Next, the video processing section 3, as shown in FIG. 3, has an A / D / D / A converter 31 and an image input control circuit 3.
2, RAM 33, and image compression / expansion circuit 34. The A / D / D / A converter 31 includes a PLL circuit, a filter circuit, and the like, and the synchronization signal, the luminance signal, the
And color signals are respectively converted into digital signals (hereinafter referred to as image data) and supplied to the image input control circuit 32, while output image data supplied from a video display unit 4 described later is converted into analog signals, The video signal is supplied to the video circuit unit 2 as a video signal.

The image input control circuit 32 includes A / D and D / A
When data is exchanged between the converter 31, the RAM 33, and the image compression / expansion circuit 34, writing to the RAM 33,
Controls reading. That is, the image input control circuit 3
2 temporarily stores the image data supplied from the A / D / D / A converter 31 in the RAM 33, and also stores the image data in the RAM based on an instruction from the CPU unit 7 described later.
The image data temporarily stored in 33 is sequentially read and supplied to the image compression / expansion circuit 34. When the image data is compressed or expanded, the image data temporarily stored in the RAM 33 is sequentially read out and the image compression / expansion circuit 34 is read.
Image data that is supplied to, or compressed or decompressed
The data is stored in a predetermined area of the AM 33.

Next, the image compression / expansion circuit 34 uses a predetermined encoding method, that is, an encoding method according to the type of image to be handled (still image in this case), for example, JPEG.
(JointPhotographic Coding Experts Group) algorithm, DCT (Discrete Cosin) for each 8 × 8 pixel block
Transform: Discrete Cosine Transform), quantization, Huffman coding, etc., and then the compressed image data is stored in the RAM via the image input control circuit 32.
Sequentially write to 33. In addition, the image compression / expansion circuit 34
Has a function of decoding and decompressing compressed / encoded image data, and compression / decompression stored in the RAM 33.
The encoded image data is converted into the image input control circuit 32.
After being sequentially read out via the, the decoding, the dequantization, or the expansion processing, the expanded image data is sequentially written into the RAM 33 again via the image input control circuit 32. As described above, the image data supplied from the video circuit 2, the compressed image data, and the decompressed image data are stored in the RAM 33 in respective predetermined areas under the control of the image input control circuit 32. It is like this.

As shown in FIG. 4, the video display unit 4 includes a display control circuit 41, a RAM 42, and an OSDC (On Scr).
een Disply controler) 43. The display control circuit 41 changes the input image data or the decompressed image data, which is position-stored in the RAM 33 of the video processing unit 3 described above, according to an instruction from the CPU unit 7 described later.
The image data is sequentially transferred to M42, and the output image data is generated by performing interpolation and thinning processing on these image data according to the display specifications, and temporarily stored in the RAM 42. In addition, the display control circuit 41 receives an instruction from the CPU unit 7 to cause the OSDC
The character stored in the character ROM built in 43 is read and combined with the output image data temporarily stored in the RAM 42, and the A / D.
It is supplied to the D / A converter 31.

The NCU section 5 is a control circuit for switching between a telephone line and a telephone, a circuit for simultaneously outputting a voice output signal to both the modem section interface and the telephone, a voice input signal from the telephone and an external voice input. Is a discrete circuit including a circuit for synthesizing the microphone input signal with the input signal. That is, the NCU unit 5 synthesizes the voice input signal from the telephone, the external voice input, and the microphone input signal, and supplies them to the voice processing unit 6 described later. Further, the NCU unit 5 sends the output audio signal supplied from the audio processing unit 6 to a telephone and an audio output terminal described later.

Next, the voice processing unit 6 is composed of a CODEC 61, a RAM 62, and a voice compression / expansion circuit 63, as shown in FIG. The CODEC 61 includes a filter, an A / D converter, and a D / A converter, and an audio signal (analog signal) from the NCU unit 5
Are digitally converted and sequentially stored temporarily in the RAM 62.
Further, the CODEC 61 converts the decoded and expanded audio data into an analog signal as described later,
It is supplied to the NCU unit 5. The voice compression / decompression circuit 63 is R
Digital audio data temporarily stored in the AM 62, for example, based on the CELP (Code-Excited Linear Prediction) algorithm, for input data of a fixed time,
A compression / encoding process is executed by a predetermined encoding method by means for analyzing, waveform combining by analyzed parameters, error calculating means for input waveform and combined waveform, etc., and the compressed audio data is temporarily stored in RAM 62. .
Further, the audio compression / expansion circuit 63, for the compressed / encoded compressed audio data stored in the RAM 62,
Decryption and decompression processing are executed and supplied to the CODEC 61.

Next, the CPU section 7, as shown in FIG.
CPU 71, RAM 72, and GA (Gate Array) 7
3 and controls each part of the present videophone device. The CPU 71 sends out various control signals for controlling each part of the video telephone device to each part via a bus and executes a communication control program according to the type of the communication line to be connected. The CPU 71 is the camera unit 1
Alternatively, after the video signal supplied from the external input terminal IN is digitized, compressed and encoded, the image data temporarily stored in the RAM 33 of the video processing unit 3 described above, the telephone or the external voice input, the microphone input After the audio signal from is digitized and compressed / encoded, it is multiplexed with the audio compression data temporarily stored in the RAM 62 of the audio processing unit 6 described above, and is transmitted as image / audio compression data via the bus. It is supplied to the modem unit 8 described later. Also,
The CPU 71 controls the modem unit 8 which will be described later for the image / sound data multiplexed and transmitted from the other party's videophone device.
When demodulated by, the demodulated image / audio data is separated, and the compressed image data is processed by the video processing unit 3 via the bus.
In addition to being stored in the RAM 33, the compressed voice data is stored in the RAM 62 of the voice processing unit 6 via the bus. The RAM 72 is a program used in the program processing executed by the CPU 71,
It is a semiconductor memory that stores data, compressed image data, audio data, and the like. Further, the GA 73 is the CPU 7
This is a collection of random logics that form one peripheral circuit, and forms, for example, an input signal receiving circuit from the remote controller 10 that controls the present videophone device.

Next, the modem section 8 is, as shown in FIG.
DSP (Digital Signal Process) that controls modulation and demodulation
ssor) 81, A / D conversion, D / A conversion, filter processing,
AFE (Analog Front End) 82 for controlling NCU 5 and interface processing with CPU, ROM 83,
And RAM 84. The DSP 81 and the AFE 82 have a function as a modulator that converts the compressed image / audio data multiplexed by the CPU 71 into a transmission signal (analog signal) that can be transmitted through a communication line and transmits the signal. Conversely, the transmission signal (analog signal) sent via the communication line
Is again provided with a function as a demodulator (demodulator) for returning to a digital signal that can be decoded by the CPU 71, and can be used as a communication line used by the NCU 5 on a general subscriber line. . RO
The M83 is a semiconductor memory that stores programs used by the DSP 81, data, and the like. RAM84 is a ROM
It is a semiconductor memory that is booted from 83 and stores a program executed by the DSP 81, and is also used as a program used in the program processing executed by the DSP 81, a buffer that stores transmission / reception data, and the like.

Further, the modem unit 8 and the NCU unit 5 in this embodiment use an analog public line at a transmission rate of 1440.
Data transmission at 0 bps (bit per second) is possible, and as a processing unit, image data, audio data, or control data is transmitted in a time-division manner as each packet configuration. At this transmission speed, normal image data for one screen can be transmitted as an intermittent image at a rate of approximately 1 frame in approximately 3.5 seconds, and in the case of detailed image data, a rate of approximately 1 frame in approximately 30 seconds. It is possible to transmit with. This data transmission method will be described later.

A-2. Connection Configuration of Videophone Device and Peripheral Equipment Next, the connection configuration of the above-described videophone device and peripheral equipment will be described with reference to FIG. FIG. 8 is a schematic diagram showing a connection configuration between a videophone device and peripheral devices. The parts corresponding to those in FIG. 1 are designated by the same reference numerals and the description thereof will be omitted. In the figure, a display device 20 such as a normal television receiver (CRT) is connected to the image output terminal OUT as a monitor of the NCU 5 of the present video telephone device.
The display device 20 may be an LCD display. Further, a telephone 21 for making a telephone call is connected to the NCU 5 of the present video telephone device by a normal modular cable. A conversation by voice is conducted by the telephone 21. Further, the telephone 21 may be provided with a so-called child device 22. Further, the NCU 5 of the present videophone device is connected to a communication line (in this case, an analog public line) via the modular jack 23.

Further, in the figure, the remote controller 10 is provided with a button switch for sending various instructions to the present video telephone apparatus. In particular, SW1 is a video circuit unit 2 from the external input terminal IN. This is a camera / video changeover switch for instructing whether to capture the image signal of 1 or the image signal from the camera unit 1. Also, SW2
Is a start / stop button that is operated prior to making a call while exchanging images with each other after the line connection with the other party is secured. Further, SW3 has the same function as the start / stop button SW2, and is provided in the main body of the present videophone device. These camera / video changeover switch SW1, start / stop button SW2, and start / stop button SW3
Will be described later.

B. Operation of Embodiment Next, the operation of the above-described embodiment will be described. In the following, a left-right reversed display process for horizontally reversing the self-portrait, a burn-in prevention process for preventing burning, and a high-speed transmission process for smoothly transmitting image data and audio data immediately after the start of a call will be described.

B-1. Left-Right Inverted Display Processing First, the left-right inverted display processing of horizontally reversing and displaying the own image will be described. 9 to 12 are flowcharts for explaining the operation of the left-right inverted display processing, and FIG. 13 is a schematic diagram showing a display example on the external display device 20. (A) Video / camera input switching process In FIG. 9, an image to be displayed on an external display device connected to the present videophone device is either an image from the external input terminal IN or an image from the camera unit 1. 8 is a flowchart of a video / camera input switching process for switching whether to perform the operation based on an operation of a camera / video switching switch SW1 provided on the remote controller 10. First, in step S10, it is determined whether or not the video input is currently selected. As described above, whether to display the image from the external input terminal IN or the image from the camera unit 1 depends on the remote controller 1
It is instructed by the camera / video changeover switch SW1 provided at 0. Then, when the image from the camera unit 1 is selected, the determination result in step S10 is “YES”, and the process proceeds to step S12.

In step S12, the control signal S1 is applied to the video circuit section 2 to switch the input image to the camera section 1 side. Therefore, in this case, in the subsequent processing, the image captured by the camera unit 1 is sent to the external display device 20 via the video circuit unit 2. On the other hand, when the image from the external input terminal IN is selected, the determination result in step S10 is "NO", and the process proceeds to step S14. In step S14, the control signal S1 is applied to the video circuit unit 2 to switch the input image to the external input terminal IN side. Therefore, in this case, in the subsequent processing, the video signal supplied from the external input terminal IN is sent to the external display device 20 via the video circuit unit 2.

(B) Left / Right Reverse Display Processing Next, when the user makes a call or when a call comes in and the handset is lifted, that is, when the user goes off-hook, the main routine shown in FIG. 10 is executed. . First, in step S20, a video through process for displaying an image on the videophone device side on the external display device 20 is executed. In this video through process, based on the above-mentioned video / camera input switching process,
It is determined whether the video to be displayed on the external display device 20 is the video from the camera unit 1 or the video from the external input terminal IN, and the left-right inverted display is performed according to the video. The details of the video through process will be described later.
Next, in step S22, it is determined whether or not the reception of the compressed image data transmitted from the other party has been completed. Then, if the reception of the compressed image data is not completed, the determination result in step S22 is "NO", the process returns to step S20, and the above-described processing is repeatedly executed.

On the other hand, if the reception of the compressed image data is completed, the result of the determination in step S22 is "YES", and the process proceeds to step S24. In step S24, a partner image display process for displaying the compressed image data transmitted from the partner on the external display device 20 connected to the videophone device is executed. In this partner image display processing, the compressed image data from the partner is expanded and displayed on the external display device 20. Details of this partner image display processing will be described later. When the partner image display process in step S24 is completed, the process returns to step S20. Hereinafter, steps S20 to S24 are repeatedly executed.

(C) Video Through Processing Next, the above video through processing will be described with reference to FIG. First, in step S30, the input image is sampled. Here, when the video from the camera unit 1 is selected in the above-mentioned video / camera input switching process, the video signal captured by the camera unit 1 is supplied to the video processing unit 3 via the video circuit unit 2. To be done. The video signal is sampled by the video processing unit 3 and then temporarily stored in the RAM 33 as image data. This image data is stored in the RAM 4 of the video display unit 4.
2 is transferred. On the other hand, when the video from the external input terminal IN is selected in the above-mentioned video / camera input switching processing, the video signal from the external input terminal IN is supplied to the video processing section 3 via the video circuit section 2. To be done.
The video signal is sampled by the video processing unit 3 and then temporarily stored in the RAM 33 as image data. This image data is transferred to the RAM 42 of the video display unit 4.

Next, in step S32, it is determined whether the image from the external input terminal IN or the image from the camera unit 1 is selected. Then, when the image from the camera unit 1 is selected, the process proceeds to step S34. In step S34, the CPU section 7 sends an inversion instruction to the display control circuit 41 of the video display section 4. Next, in step S38, the image data sampled in step S30 is displayed on the external display device 20. In this case, since the inversion instruction is supplied, RA
The image data stored in M42 is read by the display control circuit 41 in the reverse direction with respect to the horizontal direction, and then supplied to the video processing unit 3. Next, the image data is converted into an analog video signal by the A / D / D / A converter 31 of the video processing unit 3 and then, via the video circuit unit 2, a display device such as an external CRT. Sent to. In this embodiment, the screen of the external display device is divided into four as shown in FIG. 13, and the image on the videophone device side is displayed in the area A and transmitted from the other party. The incoming image is displayed in area B. In this case, the horizontally-inverted self-portrait is displayed in the area A of the external display device.

On the other hand, if the image from the external input terminal IN is selected, the process proceeds to step S36. In step S36, the CPU section 7 sends a non-inversion instruction to the display control circuit 41 of the video display section 4. Next, the process proceeds to step S38 described above, and the image data sampled in step S30 is displayed on the external display device 20. In this case, since the non-reverse instruction is supplied, the image data stored in the RAM 42 is read out in the forward direction by the display control circuit 41 and then supplied to the video processing unit 3.
Next, the image data is the A / D / D of the video processing unit 3.
After being converted to an analog video signal by the A / A converter 31, the external display device 20 is connected via the video circuit unit 2.
Sent to In this case, an image that is not horizontally reversed is displayed in the area A of the external display device.

(D) Partner Image Display Processing Next, the partner image display processing described above will be described with reference to FIG. The compressed image data transmitted from the other party via the communication line is demodulated by the modem unit 8,
It is temporarily stored in the RAM 33 of the video processing unit 3. RAM
The image data stored in 33 is first of all in step S40.
In, the image is expanded by the image compression / expansion circuit 34,
After being stored in the RAM 33 again, it is further transferred to the RAM 42 of the video display unit 4. Next, step S42.
In the CPU, after sending a non-inversion instruction from the CPU section 7 to the display control circuit 41 of the video display section 4, the process proceeds to step S44, and the image data decompressed in step S40 is combined with the image data of the videophone device side, Is displayed on the display device 20. In this case, since the non-inversion instruction is supplied, the received image data stored in the RAM 42 is read by the display control circuit 41 in the forward direction and then supplied to the video processing unit 3. Next, the image data is converted into a video signal of an analog signal by the A / D / D / A converter 31 of the video processing unit 3, and then sent to the external display device 20 via the video circuit unit 2. It In this case, an image that is not horizontally inverted is displayed in the area B of the external display device 20.

In the above-mentioned left-right reversed display processing, whether the left-right reversed display or the non-left-right reversed display is performed is whether the input video is the video from the external input terminal IN or the video from the camera section 1. However, the present invention is not limited to this and may be switched by operating the switch of the key / LED 9 or the remote controller 10. For example,
When the user's face is photographed by the video camera connected to the external input terminal IN, it is preferable to display the face by reversing it as in the case of photographing by the camera unit 1. Therefore, in this case, the key / LED 9 or the remote controller 10
The image input from the external input terminal IN is horizontally reversed and displayed by the switch operation.

As described above, in the above-described left-right reversed display processing, only the self-portrait displayed on the screen of the external display device 20 is left-right reversed and displayed. The self-portrait also moves, which makes it easier to position your face. Also, the external input terminal IN
Since the video from and the received video of the other party are displayed as they are, the video of the other party can be viewed naturally, and when the text is included, the text can be read as it is.

B-2. Image sticking prevention process Next, image sticking prevention process for preventing image sticking will be described. FIG. 14 is a flowchart for explaining the operation of the burn-in prevention process, and FIGS.
[Fig. 6] is a schematic diagram showing a display example of the display device 20 in the main burn-in prevention process. When the videophone device is powered on, the flowchart shown in FIG. 14 is executed. First, in step S50, the CPU 71 of the CPU unit 7
Supplies the control signal S1 to the video circuit 2 to turn on the image output switch in the video circuit 2. next,
In step S52, the opening message prepared in advance is displayed on the display device 20 connected to the outside. That is, in response to a command from the CPU unit 7, the display control circuit 41 of the video display unit 4 reads the opening message (character) stored in the character ROM built in the OSDC 43 and temporarily stored in the RAM 42. It is combined with the output image data and supplied to the A / D / D / A converter 31 of the video processing unit 3 described above. The opening message is the A / D / D / A converter 3
After being converted into an analog video signal by 1, the video signal is supplied to the video circuit unit 2, and as shown in FIG.
It is displayed on the external display device 20.

Next, in step S54, it is determined whether or not T seconds have elapsed since the opening message was displayed. Then, when T seconds have not elapsed, the determination result in step S54 becomes "NO", and step S54 is repeatedly executed until T seconds elapse. On the other hand, when T seconds have elapsed, the determination result in step S54 is "YES", and the process proceeds to step S56. In this way, when the power is turned on, the opening message is displayed for a fixed time (T seconds). In step S56, the video display unit 4, the video processing unit 3, and the video circuit unit 2
As shown in FIG. 15B, a black image (minimum brightness, no color) is displayed on the external display device 20 via.
Next, in step S58, the image output switch of the video circuit unit 2 is turned off by the control signal S1. As a result, no video signal is output from the image output terminal OUT. Here, in step S56, a black image is temporarily displayed because when the image output switch of the video circuit unit 2 is turned on / off, the screen of the display device 20 is disturbed due to a momentary loss of synchronization. This is to prevent this. By displaying a black image before turning on / off the image output switch, the disturbance of the screen is made inconspicuous. In this way, after displaying the opening message, the external display device 20
Nothing is displayed in (standby mode).

Next, in step S60, when a call is made or a call is received from the other party, it is determined whether or not the handset is lifted to go off-hook. If it is not off-hook, the determination result in step S60 is "NO", and step S60 is repeatedly executed. On the other hand, when a call is made or when a call is received from the other party and the handset is lifted to go off-hook, the determination result in step S60 is "YES".
Then, the process proceeds to step S62. In step S62,
The control signal S is sent from the CPU 71 of the CPU section 7 to the video circuit 2.
1 is supplied to turn on the image output switch in the video circuit 2. Next, in step S64, similarly to step S56 described above, the external display device 20
To display a black image once.

Next, in step S66, a call process by the videophone is performed. That is, the video signal captured by the camera unit 1 is supplied to the video processing unit 3 via the video circuit unit 2. The video signal is processed by the video processing unit 3
After being sampled by
It is temporarily stored in M33. This image data is transferred to the RAM 42 of the video display unit 4. Next, the image data stored in the RAM 42 is read by the display control circuit 41 and then supplied to the video processing unit 3. The image data is converted into the A / D / D / A converter 31 of the video processing unit 3.
After being converted into a video signal of an analog signal by, it is sent to the external display device 20 via the video circuit unit 2 and displayed in the area A of the display device 20 as shown in FIG. The compressed image data transmitted from the other party via the communication line is demodulated by the modem unit 8,
It is temporarily stored in the RAM 33 of the video processing unit 3. RAM
The image data stored in 33 is the image compression / expansion circuit 3
4 is expanded and stored again in the RAM 33, and then further transferred to the RAM 42 of the video display unit 4. Next, after the image data stored in the RAM 42 is read by the display control circuit 41, the video processing unit 3
Supplied to The image data is A of the video processing unit 3.
After being converted into an analog video signal by the D / D / D / A converter 31, the video signal is sent to the external display device 20 via the video circuit unit 2, and as shown in FIG. Is displayed in area B of.

In the above-mentioned call processing, in step S68, it is determined whether or not the call is hung up, that is, whether or not the call is on-hook. Then, if it is not on-hook, the determination result in step S68 is "NO", the process returns to step S66, and the above-described call processing is repeatedly executed. On the other hand, when the call ends and the call is disconnected,
The determination result in step S68 is “YES”,
Return to step S56. Hereinafter, in step S56, a black image is displayed on the display device 20, and in step S58, the image output switch of the video circuit unit 2 is turned off, and the steps S56 to S68 are repeated.

As described above, in the above-described image sticking prevention processing, the image output switch of the video circuit unit 2 is turned off to prevent the video signal from being output except during a call, so that the image sticking of the screen of the display device 20 is prevented. it can. In the call processing of the above-described image sticking prevention processing, when the self-portrait and the image of the other party are displayed on the external display device 20, the above-described left-right reverse display processing is applied to display the self-portrait in the left-right inverted manner. You may Further, in the above-mentioned call processing of the burn-in prevention processing, the video signal is automatically output only during the call, but the key / LED 9 or the remote controller 10 may be output as necessary even when the call is not being performed.
The video signal may be output by operating an operator (switch) provided on the.

B-3. High-speed transmission process Next, a high-speed transmission process for smoothly transmitting image data and audio data immediately after the start of a call will be described. FIG. 16 is a schematic diagram showing a format of data transmission in the normal time in the video telephone device, and FIG. 17 and FIG.
8 is a flowchart for explaining the operation of the high speed transmission process. First, the format of data transmission in this videophone device will be described. As shown in FIG. 16, in the present videophone device, as described above, image data, audio data, and control data are time-divisionally transmitted in packet units. Each data has a header and CRC
The code is added, and the image data actually effective for transmission is about 7,000 bps, and the voice data is about 7,000 bps.
Has become. In other words, as the image data, as in the present embodiment, when color image data of 4096 colors (12 bits) with 112 × 128 pixels in one screen is handled, the pixel data amount of one screen is 112 × 128 × 12 = 17203.
Although it is 2 bits (about 21.5 kilobytes), the data can be compressed to about 1/7 by image compression processing. Therefore, an intermittent still image is transmitted at a rate of 1 frame every 24500 bits of image data divided by the number of bits that can be transmitted per second (about 7,000 bits), that is, 24500 ÷ 7000≈3.5 seconds. Become. In this way, in actuality, 49152-bit image data obtained by dividing 172032 bits by 3.5 seconds is compressed to about 1/7 and transmitted as about 7000-bit image data. On the other hand, audio data is treated as digital data sampled at 12 bits and 8 kHz, and this 12 × 8
The audio data of 000 = 96000 bits is compressed to about 1/14 and transmitted as audio data of about 7000 bits.

Next, a description will be given of the processing at the start of the call and during the call. When a call is made to the other party or a call is received from the other party, the power of this videophone device is automatically turned on and PinP (Picture in P
icture) screen displays the self-portrait photographed by the camera unit 1 on the external display device 20. The self-portrait at this time is displayed as a 1/16 small screen. After confirming that the self-portrait is displayed, the user can
The start / stop button SW2 provided on the remote controller 9 or the start / stop button SW3 provided on the remote controller 10 is pressed. Then, for example, when the start / stop button SW2 is pressed, FIG. 17 and FIG.
The flowchart shown in is executed by the CPU 71.

First, in step S70, the V. 32
A connection request (negotiating request) according to bis is issued to the modem unit 8. Next, in step S72, the V. 32bi
It is determined whether or not the connection request by s is completed. If the connection request is not completed, step S7
The determination result in 2 is “NO”, and the same step S7
Repeat 2 On the other hand, when the connection request is completed,
The determination result in step S72 is “YES”,
It proceeds to step S74. In step S74, the compressed voice data transmitted from the other party via the public line is received. This compressed audio data is supplied to the modem unit 8 via the NCU unit 5, demodulated by the modem unit 8, and then read by the CPU 71 via the bus. C
The PU 71 determines that the data is audio data by discriminating the audio header, and then supplies the audio data to the audio processing unit 6. The voice data is decompressed by the voice compression / decompression circuit 63 of the voice processing unit 6, converted into an analog signal by the CODEC 61, and output via the NCU unit 5 to the telephone 21 connected to the outside.

Next, in step S76, the camera unit 1
The image data captured by is transmitted to the other party via the public line according to the procedure described later. Next, in step S78, the compressed image data transmitted from the other party via the public line is received according to the procedure described later. Then, in step S80, it is determined whether the transmission of the image data for one screen is completed. Here, if the transmission of the image data for one screen is not yet completed, the determination result in step S80 is "NO", and the process proceeds to step S82. In step S82, it is determined whether the reception of the image data for one screen is completed.
When the reception of the image data for one screen is not completed, the determination result in step S82 is "NO".
Then, the process returns to step S74. Hereinafter, step S is performed until either one screen of image data is transmitted or received.
74 to S82 are repeatedly executed.

The image data transmission / reception processing described above will be described. First, in the image data transmission processing in step S76, the image data photographed by the camera unit 1 is stored in the video circuit unit 2 and the video processing unit 3. A
After being temporarily stored in the RAM 33 via the / D / D / A converter 31 and the image input control circuit 32, it is compressed by the image compression / expansion circuit 34 by a predetermined compression method. The compressed image data is read by the CPU 71 via the bus. The CPU 71 adds an image header to this compressed image data and then sends it to the modem unit 8 via the bus.
The modem unit 8 adds CRC to the compressed image data to which the header is added and modulates the compressed image data, and then transmits the compressed image data to the other party via the public line. On the other hand, in the image data transmission process in step S78, the image data received via the public line is demodulated by the modem unit 8 via the NCU unit 5 and read by the CPU 71 via the bus. C
The PU 71 discriminates the image header to confirm that the image data is image data, and then the PU 71 is supplied to the video processing unit 3 via the bus and temporarily stored in the RAM 33.

When only the transmission of the image data for one screen is completed in the reception of the voice data, the transmission of the image data, and the reception of the image data described above, the determination result in step S80 is "YES", and the process proceeds to step S84. In step S84, it is determined whether the reception of the image data for one screen is completed. When the reception of the image data for one screen is not completed, the determination result in step S84 is "NO", and the above-described step S8 is performed.
2, the steps S74 to S84 are repeated. When only one screen of image data is received in the above-described audio data reception, image data transmission, and image data reception, the determination result in step S82 is "YES", and the process proceeds to step S86.

In step S86, it is determined whether the transmission of the image data for one screen is completed. Then, when the transmission of the image data for one screen is not completed, the determination result in step S86 becomes "NO", the process returns to step S74, and steps S74 to S86 are repeatedly executed. On the other hand, when the reception of the image data for one screen is completed after the transmission of the image data for one screen is completed,
The determination result in step S84 is “YES”,
It proceeds to step S88. Similarly, when the transmission of the image data for one screen is completed after the reception of the image data for one screen is completed, the determination result in step S86 is “Y”.
ES ”, and the process proceeds to step S88. That is, the process proceeds to step S88 only when the transmission / reception of the image data for one screen is completed in steps S46 and S78. In step S88, the received image data is decompressed and displayed on the external display device 20.

That is, in step S88, the compressed image data received via the public line and temporarily stored in the RAM 33 is the image compression / expansion circuit 34 of the video processing unit 3.
After being expanded by, it is supplied to the video display unit 4 via the bus. In the video display unit 4, the expanded image data is displayed by the display control circuit 41 in the A of the video processing unit 3.
The signal is supplied to the / D / D / A converter 31, converted into an analog signal, and then output via the video circuit unit 2 to the display device 20 connected to the outside. Next, proceeding to step S90 shown in FIG. 18, voice data is transmitted. That is,
The voice data input from the receiver of the external telephone 21 is supplied to the voice processing unit 6 via the NCU unit 5 and compressed according to a predetermined compression method. Next, the compressed audio data is read by the CPU 71 of the CPU unit 7 via the bus. The CPU 71 adds a voice header to the compressed voice data, and then supplies the compressed voice data to the modem unit 8 via the bus. In the modem unit 8, the compressed voice data to which the upper voice header is added is added to the CRC and modulated, and then transmitted to the other party via the public line.

Next, in step S92, the voice data transmitted from the other party via the public line is received, as in step S74 described above. Then, in step S94, the image captured by the camera unit 1 is transmitted. Next, in step S96, after receiving the image data transmitted from the other party via the public line, the process returns to step S90. Hereinafter, steps S90 to S96 are repeatedly executed until the handset of the telephone connected to the outside is placed and the on-hook state is set, and voice data and image data are transmitted and received.

In the high-speed transmission processing described above, the transmission of the audio data was started at the time when the transmission / reception of the image data was completed. You may make it start transmission of audio | voice data at the time when it passes. As described above, in the above-described high-speed transmission processing, immediately after the call is started, the voice data is not transmitted until at least the transmission / reception of the image data for one screen is completed. Therefore, until the first screen is displayed. The time can be shortened and the call can be started from the time when both of them receive the image, so that the user can talk in a natural state while watching the image of the other party.

In the above-mentioned embodiment, the compression method of the image data is not limited to the JPEG algorithm but may be, for example, a block coding method, a predictive coding method or the like, and a compression method of the audio data. as,
Not limited to the CELP algorithm, for example, AD / PCM
(Adaptive Differential Pulse Code Modulation) method, VSELP (Vector Sum Excited Liner Predictio)
n) method may be used.

[0061]

According to the present invention, the screen of an external display device connected to the device is divided into a plurality of areas, and only the image displayed in a specific area of the plurality of areas is horizontally inverted. Since it is displayed, the following advantages can be obtained. (1) If the self-portrait is displayed in a specific area, the self-portrait is displayed in left-right inversion, so that the self-portrait can be easily aligned. (2) Also, if the image from the external input terminal or the image of the other party received is displayed in a region other than the specified area, it will not be flipped horizontally.For example, if the image contains characters. Can be read as is.

Further, the self-portrait which has been left-right inverted by the left-right inversion means and the other-side image of the other party transmitted via the communication line are displayed on the external display device connected to the device by the display control means. Therefore, the following advantages can be obtained. (1) The self-portrait can be easily aligned by reversing the image. (2) Further, the image from the external input terminal or the image of the other party received is displayed as it is, so that even if the image contains characters, it can be read as it is.

Further, since the switching means outputs the image captured by the image capturing means from the output terminal only when the off-hook state is detected by the detecting means, the following advantages can be obtained. (1) Since the video signal is output to the outside only when making a call or receiving a call, burning can be prevented. (2) Since the output / non-output of the video signal is automatically controlled according to the detection of the off-hook state, when making a call or
Whenever a call is received, it is not necessary to turn on the power of the external display device each time, and the operation is easy. (3) When not in a call, the standby mode is set, so that power consumption can be reduced. (4) If the output / non-output of the video signal is selectively switched by the operator means, the person's appearance can be monitored and the video capture means (camera) can be adjusted or the other party can be called before the call. The video to be transmitted can be sampled in advance and stored.

At the start of communication, the communication means transmits / receives an image to / from the other party, and when the transmission / reception of at least one screen image is completed, the communication means transmits / receives an audio to / from the other party. Since it is controlled by the communication control means so as to start, the following advantages can be obtained. (1) Since the voice is not transmitted until the transmission / reception of the video for at least one screen is completed, the time until the first video is displayed can be shortened. (2) Since the voice is transmitted and received when the video transmission and reception is completed, you can talk in a natural state while watching the video of the other party.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of a videophone device according to an embodiment of the present invention.

FIG. 2 is a block diagram showing a configuration of a camera unit of the videophone device according to the present embodiment.

FIG. 3 is a block diagram showing a configuration of a video processing unit of the videophone device according to the present embodiment.

FIG. 4 is a block diagram showing a configuration of a video display unit of the videophone device according to the present embodiment.

FIG. 5 is a block diagram showing a configuration of an audio processing unit of the videophone device according to the present embodiment.

FIG. 6 is a block diagram showing a configuration of a CPU unit of the videophone device according to the present embodiment.

FIG. 7 is a block diagram showing a configuration of a modem unit of the videophone device according to the present embodiment.

FIG. 8 is a schematic diagram showing a connection configuration of a videophone device according to the present embodiment and peripheral devices connected thereto.

FIG. 9 is a flowchart of a video / camera input switching process for switching an image to be displayed on an external display device connected to the present videophone device.

FIG. 10 is a flowchart for explaining the operation of the main routine of the left-right reversed display processing.

FIG. 11 is a flowchart for explaining the operation of video through processing.

FIG. 12 is a flowchart for explaining an operation of a partner image display process.

FIG. 13 is a schematic diagram showing a display example on an external display device in the left-right inverted display processing.

FIG. 14 is a flowchart illustrating an operation of a burn-in prevention process.

FIG. 15 is a schematic diagram showing a display example of a display device in a burning prevention process.

FIG. 16 is a schematic diagram showing a format of data transmission in a normal state in the present videophone device.

FIG. 17 is a flowchart for explaining the operation of high-speed transmission processing.

FIG. 18 is a flowchart for explaining the operation of high-speed transmission processing.

[Explanation of symbols]

 1 camera section (video capturing means) 2 video circuit section (display video switching means, switching means) 3 video processing section (display control means) 4 video display section (horizontal reversing means, video control means) 5 NCU 6 audio processing section 7 CPU section (detection means, communication control means) 8 Modem section (communication means) 9 Key / LED section 10 Remote control (operator means) 11 Lens 12 CCD 13 CCD driver 14 A / D / D / A converter 15 DSP 31 A / D / D / A converter 32 Image input control circuit 33 RAM 34 Image compression / expansion circuit 41 Display control circuit (left / right inversion means) 42 RAM 43 OSDC 61 CODEC 62 RAM 63 Audio compression / expansion circuit 71 CPU (detection means, communication) Control means) 72 RAM 73 GA 81 DSP 82 AFE 83 ROM 84 RAM 20 Display device (external Display device) 21 phone 22 slave unit 23 modular jack IN image input terminal OUT image output terminal (output terminal) SW1 camera / video change-over switch SW2, SW3 start / stop button

Claims (13)

[Claims] 1. A screen of an external display device connected to the device is divided into a plurality of areas, and only an image displayed in a specific area of the plurality of areas is horizontally reversed. Videophone device. 2. A video capturing means for capturing at least a self-portrait of a user, a communication means for receiving a partner image of a destination transmitted via a communication line, and a self-portrait captured by the video capturing means to the left and right. And a display control means for simultaneously displaying the partner image received by the communication means and the self-portrait inverted by the left / right reversing means on an external display device connected to the apparatus. Characteristic videophone device. 3. One of a self-portrait captured by the video capturing means and a video supplied from the outside,
3. The videophone apparatus according to claim 1, further comprising display image switching means for selectively switching the image to be displayed on the external display means and supplying the image to the left / right inverting means. 4. The left and right reversing means, when an image supplied from the outside by the display image switching means is selected, displays the image on the external display means without horizontally reversing. The videophone device according to items 1 or 2. 5. A manipulator means for instructing the left / right reversing means whether to display the image captured by the device in left / right reversal display or in non-left / right reversal display. The videophone device described. 6. The image captured by the device is digital data stored in a predetermined storage means, and the left / right reversing means reverses the horizontal direction of the image stored in the storage means. 4. The videophone device according to claim 1, wherein the videophone device is horizontally flipped when read. 7. An image capturing means for capturing an image, a detecting means for detecting whether or not the telephone is in an off-hook state, and an image capturing means for detecting an off-hook state only by the detecting means. A videophone device, comprising: a switching unit that outputs the captured video from an output terminal. 8. A video control means for turning on the switching means when the apparatus is powered on and outputting an opening message stored in advance from the output terminal for a predetermined time. Item 7. The videophone device according to Item 7. 9. The image control means outputs a black image to the output terminal prior to the switching operation of the image output / non-output by the switching means.
The videophone device described. 10. The videophone according to claim 7, wherein the switching means is a switch which is provided at a final stage of outputting the video signal and which is turned on / off based on a control signal from the detection means. apparatus. 11. The operating means means for instructing to turn on the switching means and output an image from an output terminal regardless of the detection of the off-hook state by the detecting means. Videophone device. 12. A communication means for transmitting and receiving video and audio through a communication line, and at the start of communication, the communication means transmits and receives the video, and the transmission and reception of at least one screen of video is completed. And a communication control means for starting transmission / reception of voice by the communication means to / from a partner at a point of time. 13. The communication control means, when the transmission time required to transmit / receive one screen of video is constant, transmits / receives video to / from a partner at the start of communication by the communication means, 13. The videophone device according to claim 12, wherein when the transmission time has elapsed, transmission and reception of voice with the voice partner is started by the communication means.