JPH08265717A - Video telephone system - Google Patents

Abstract

PURPOSE: To obtain a video telephone system capable of closing up a screen and performing magnified display without using a zoom lens in an image pickup part. CONSTITUTION: This system is provided with a camera part 22 for digitizing image data and voice data generated by the image pickup part 21 and a receiver 3 in an A/D conversion part 4, an image processing part 23 for compressing the data from the camera part 22 in a codec part 8, then multiplexing the image data and the voice data and generating video data, a magnification processing part 25 for converting the resolution of a magnification range specified in a magnification range specifying part 26 in a resolution conversion part 27, a transmission/reception part 11 for outputting the video data to a line, a display part 16 for outputting the data from the image processing part 23 as video images, an operation part 17 for performing the various kinds of operations and a CPU 18 in charge of the overall control of the system. Then, the magnification processing part 25 converts the resolution in the A/D conversion part 4 which is the preceding stage of a compression processing in the codec part 8.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a videophone device having a magnifying display function.

[0002]

2. Description of the Related Art In recent years, along with the widespread use of video telephone devices, there has been a demand for an enlarged display function capable of closing up the central portion of the screen. FIG. 6 is a block diagram showing the configuration of such a conventional videophone device.

In FIG. 6, an image pickup section 1 is composed of a lens, a diaphragm, and an image pickup element such as a CCD. Incident light from the subject captured by the image capturing unit 1 is sent to the encoder 2 after being converted from an optical signal into an electrical signal. The electric signal sent to the encoder 2 is converted into image data composed of a luminance signal and a color signal defined by NTSC, PAL, etc., and then sent to the A / D converter 4 together with the voice data captured by the handset 3. . Both analog data sent to the A / D converter 4 are digitized and temporarily stored in the input memory 5. The data processed by the camera unit 6 is sent to the codec unit 8 of the image processing unit 7, and the codec unit 8 uses the memory 9 for codec processing to encode and compress the data sent from the memory 5. . Since the codec unit 8 reversibly encodes and compresses the data, the data can be restored by the reverse process. In the subsequent demultiplexing unit 10, the image data and audio data are multiplexed and integrated into video data. Since the multiplexing / separating unit 10 also reversibly multiplexes the image data and the audio data, the video data can be separated into the image data and the audio data by the reverse processing. The video data thus multiplexed is sent to the transmission / reception unit 11, then sent to the line 13 via the interface unit 12 (line interface unit), and is projected on the videophone device of the other party.

On the other hand, the video data transmitted from the other party's videophone through the line 13 is separated into image data and audio data by the demultiplexing unit 10 via the interface unit 12. Then, both data that have been encoded and compressed are decoded and decompressed by the codec unit 8 and then temporarily stored in the output memory 14. After that, the digital data sent from the memory 14 is converted into an analog signal by the D / A conversion unit 15 and the CRT.
It is displayed on the display unit 16 such as a (cathode ray tube display) or LCD (liquid crystal display).

The image pickup section 1 of the camera section 6 described above is provided with a zoom lens so that the vicinity of the central portion of the screen can be enlarged and displayed on the display section 16 in an enlarged manner. Less than,
An enlarged display function of the videophone device using the zoom lens will be described with reference to FIG. 6 and FIG. 7 which are schematic diagrams showing a call state in the conventional videophone device.
In FIG. 6, the main part 19 is the part excluding the image pickup part 1, the display part 16, the operation part 17, and the CPU 18 from the videophone device shown in FIG.

In order to activate the enlargement display function of the other party's videophone device by remote control and to enlarge and display the image on the display section 16 of the own side videophone apparatus, first, the operation section 17 of the own side videophone apparatus. Performs a predetermined operation for remotely controlling the other party's videophone device. Then, the CPU 18, which is responsible for the overall control of the system, sends an operation signal for operating the imaging unit 1 on the other side to the interface unit 12 via the D interface unit 20 (D channel signal interface unit) of the transmission / reception unit 11, and the interface unit 12 The section 12 transmits an operation signal to the line 13 together with the video data.

On the other hand, in the video telephone apparatus of the other party, the interface section 12 receives the video data and the operation signal sent from the line 13, and the D interface section 2
At 0, the operation signal is separated and transmitted to the CPU 18. Then,
The CPU 18 operates the zoom lens of the image pickup unit 1 based on the operation signal, shifts from the standard side to the telephoto side, and closes up the vicinity of the center of the screen. Then, this enlarged image is transmitted from the videophone device on the other side to the videophone device on the self side and is displayed on the videophone device on the self side.

On the contrary, it is also possible to send a close-up image to the other party in advance by the videophone apparatus on the own side. In this case, a predetermined operation is performed from the operation unit 17, and the image on the self side is switched to be displayed on the display unit 16 on the self side. Then, the zoom lens of the image pickup unit 1 on the self side is operated to shift from the standard side to the telephoto side to close up the vicinity of the central portion. When the video image displayed on the display unit 16 on the self side is confirmed, a predetermined operation is performed again from the operation unit 17 and the close-up video image on the self side is sent to the line 13 and transmitted to the other side. At this time, the image on the display unit 16 on the self side is switched to the image sent from the videophone device on the other side. If the enlarged display function is limitedly used only on the self side on the assumption that the videophone device on the other side is not remotely controlled, the D interface section 20 of the transmission / reception section 11 becomes unnecessary.

Since the image of the display unit 16 which is taken up as a close-up image is taken up at the first stage of the image pickup unit 1, the resolution on the screen is naturally higher than that of the image before the close-up. does not change.

[0010]

However, in the conventional videophone apparatus as described above, the image pickup section 1 is required to have a telephoto function for enlarging and enlarging the vicinity of the central portion of the screen. However, if a zoom lens is adopted in the image pickup unit 1 in order to provide the telephoto function, the image pickup unit 1 is inevitably used.
However, there is a problem in that the size becomes large and the size and weight cannot be reduced, and the cost increases.

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above problems and to provide a videophone device capable of enlarging and displaying a screen close-up without using a zoom lens in an image pickup section.

[0012]

In order to solve the above problems, the video telephone apparatus of the present invention has a camera section for digitizing image data and voice data generated by an image pickup section and a handset by an A / D conversion section. An image processing unit that compresses data from the camera unit by the codec unit and then generates image data by multiplexing image data and audio data; and resolution conversion of the resolution of the expansion range specified by the expansion range specification unit. Enlargement processing unit that converts in the unit, transmission / reception unit that outputs video data to the line, display unit that outputs data from the image processing unit as video, operation unit that performs various operations, and overall control of the system The enlargement processing unit is provided with a CPU, and the resolution is converted by the A / D conversion unit before the compression processing in the codec unit.

[0013]

With this configuration, the compression process in the codec unit inevitably involves a decrease in resolution, but the expansion process can be performed at a high resolution stage before that. Therefore, even if the image is enlarged and displayed in close-up by image processing without using the zoom lens, the normal resolution can be maintained after the compression processing.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings, but it is assumed that this embodiment is used for both calls by a videophone device. The same parts as those in the conventional example are designated by the same reference numerals.

FIG. 1 is a block diagram showing the structure of a videophone apparatus according to an embodiment of the present invention. The structure of this embodiment is substantially the same as that of the conventional example except for the enlarged display function.

In FIG. 1, the image pickup section 21 is composed of a lens, a diaphragm, and an image pickup element such as a CCD. Incident light from the subject captured by the imaging unit 21 is converted into an electrical signal from an optical signal and then sent to the encoder 2. The electric signal sent to the encoder 2 is converted into a luminance signal and a color signal specified by NTSC, PAL, etc., and then the handset 3
It is sent to the A / D conversion unit 4 together with the audio signal captured by. A
Both analog data sent to the / D conversion unit 4 are digitized and temporarily stored in the input memory 5. The data processed by the camera unit 22 is sent to the codec unit 8 of the image processing unit 23, and the codec unit 8 uses the memory 9 for codec processing to encode and compress the data sent from the memory 5. Since the codec unit 8 reversibly encodes and compresses the data, the data can be restored by the reverse process. In the subsequent demultiplexing unit 10, the image data and audio data are multiplexed and integrated into video data. Since the multiplexing / separating unit 10 also reversibly multiplexes the image data and the audio data, the video data can be separated into the image data and the audio data by the reverse processing. The video data thus multiplexed is sent to the transmission / reception unit 11 and then the interface unit 1
It is transmitted to the line 13 via 2 and is projected on the videophone device of the other party.

On the other hand, the video data transmitted from the other party's videophone through the line 13 is separated into image data and audio data by the demultiplexing unit 10 via the interface unit 12. Then, both data that have been encoded and compressed are decoded and decompressed by the codec unit 8 and then temporarily stored in the output memory 14. After that, the digital data sent from the memory 14 is converted into an analog signal by the D / A conversion unit 15 and displayed on the display unit 16 such as a CRT or LCD.

Unlike the conventional example, the image pickup section 21 of the camera section 22 described above is provided with only a single-focus lens.
It is not possible to close up the vicinity of the central portion of the screen at the stage of the image pickup unit 21 and enlarge and display it on the display unit 16. Even if the image currently displayed on the display unit 16 is forcibly closed up by the image processing at the stage of the display unit 16, the resolution of the main image is constant. A screen that is degraded and enlarged becomes difficult to see.

By the way, when comparing the resolution of the image as the video telephone device before and after the data compression processing in the codec section 8, the resolution before the compression processing is far finer than the resolution after the compression processing. Specifically, the resolution at the output stage of the encoder 2 before compression processing is, for example, 510 ×
It has a high resolution of 492 dots (corresponding to about 300 horizontal resolutions, and the resolution at this stage is proportional to the number of pixels of the image sensor such as CCD), while the resolution after compression processing is, for example, The upper limit is set for the low resolution of 176 × 144 dots (QCIF format of H261 standard). The reason why the resolution is low after the compression process is that the line 13 is subject to the restriction of the transmission rate again in addition to the restriction of the data capacity and the transmission rate of the data compression processing in the codec unit 8.

Therefore, close-up by image processing is performed at the high resolution stage before data compression processing in the codec section 8, and the resolution of the image after close-up is higher than the resolution after compression processing (for example, 176 × 144 dots). Try to keep it. By doing so, both the resolution of the close-up image and the resolution of the image before the close-up will be transmitted at the same level of resolution (176 × 144 dots) after the compression processing in the codec unit 8. Even with this, it is possible to prevent the resolution of the image from being lowered.

The above description will be described with reference to FIG. 2 which is a schematic diagram showing a change in resolution of the videophone apparatus according to the embodiment of the present invention.

Area A of the screen displayed on the display unit 16
Represents a full screen of 510 × 492 dots, and area B represents a screen of 176 × 144 dots. Although the actual expansion range is limited by the processing speed of the A / D conversion unit 4, theoretically, even if the image of the area B is enlarged and expanded to the area A, the resolution after the compression processing by the codec unit 8 is increased. Can maintain 176 × 144 dots. Of course, even if the image of the area C of 264 × 216 dots, which is wider than the area B, is closed up and enlarged to the area A, the resolution after the compression processing in the codec unit 8 can be maintained at 176 × 144 dots similarly. However, 132 narrower than region B
When the image of the area D of × 108 dots is enlarged and expanded to the area A, the resolution after compression processing in the codec unit 8 can no longer maintain 176 × 144 dots, and
We have to accept the low resolution of 32 × 108 dots.

In other words, the 176 × 144 dots in the area B is a practical threshold value (shikiichi) when the codec section 8 performs compression processing, and the areas A and C wider than the area B are in the codec section 8. After the compression process, there is a threshold constraint 17
It converges to 6 × 144 dots. However, the area D, which is narrower than the area B, is not restricted by the threshold value and is 132 × 10
Keep 8 dots as is.

The enlarged display function of the videophone device by image processing will be described below with reference to FIG. 1 and FIG. 3 which is a schematic diagram showing a call state in the videophone device according to the embodiment of the present invention. 3, the image pickup unit 21, the display unit 16, the operation unit 1 from the videophone device shown in FIG.
7, the part excluding the CPU 18 is shown as a main part 24.

To remotely activate the enlargement display function of the other party's videophone device and display the enlarged image on the display section 16 of the own side videophone apparatus, use the operation section 17 of the own side videophone apparatus. Performs a predetermined operation for remotely controlling the videophone device of the other party. When the enlargement range designating unit 26 of the enlargement processing unit 25 is operated, the horizontal and vertical coordinates of one frame of the screen correspond to the screen of the display unit 16, so the operation unit 17 is operated to display the current display screen. The part to be magnified and displayed is arbitrarily defined and is used as a magnifying frame. Then, the CPU 18, which is responsible for the overall control of the system, processes the coordinate data of the enlargement frame, and transmits the coordinate data of the enlargement frame to the interface unit 12 via the D interface unit 20 together with the operation signal for operating the videophone device of the other party. Then, the interface unit 12 transmits the operation signal and the coordinate data of the enlargement frame to the line 13 together with the video data.

On the other hand, the video telephone apparatus on the other side receives the operation data and the coordinate data of the enlarged frame at the interface section 12 together with the video data sent from the line 13.
The D interface unit 20 separates the operation signal and the coordinate data of the enlargement frame and sends it to the CPU 18. Then, CPU1
Reference numeral 8 activates the enlargement range designation unit 26 and the resolution conversion unit 27 of the enlargement processing unit 25 based on the operation signal and the coordinate data of the enlargement frame. The enlargement range designation unit 26 is an enlargement frame (a portion to be closed up) based on the coordinate data of the enlargement frame sent.
The resolution conversion unit 27 calculates the number of samples and the sampling frequency in order to sample the luminance signal and the chrominance signal in accordance with the displayed enlargement frame. The number of samples is the same as the number of samples on the standard display screen before the enlargement process, and the sample frequency is different before and after the enlargement process. In the resolution conversion unit 27, the arbitrarily designated enlargement frame is displayed on the display unit 16.
In order to maximize the display on the screen, the display range is corrected by mixing the double reading and the third reading in the vertical direction based on the horizontal-vertical ratio (aspect ratio) of the screen. Then, the A / D converter 4 samples the luminance signal and the color signal based on the calculated sample number and the sample frequency, and digitizes the analog data.

Since the resolution of the enlarged frame portion at this stage exceeds the resolution after the compression processing in the codec section 8, the resolution after the compression processing in the codec section 8 is the same as in the case of the standard display screen. 176 × 144 dots can be maintained. The data digitized by the A / D conversion unit 4 is temporarily stored in the memory 5 and then compressed by the codec unit 8. At this time, the codec unit 8 uses the timing in the case of the standard display screen. Data is read from the takeover memory 5. By doing so, the compression process can be performed in the enlarged display screen in the same time as in the standard display screen.

After that, the same processing as in the case of the standard display screen is performed, and the enlarged image is transmitted from the videophone device on the other side to the videophone device on the self side and is displayed on the videophone device on the self side. It

On the contrary, it is possible to send a close-up image to the other party by the video telephone apparatus on the own side. In this case, a predetermined operation is performed from the operation unit 17 to switch the image on the self side to be displayed on the display unit 16 on the self side, and the enlargement range designation unit 26 and the resolution conversion unit 27 on the self side.
Is operated to close up the portion of the enlargement frame arbitrarily determined as described above. When the video image displayed on the display unit 16 on the self side is confirmed, a predetermined operation is performed again from the operation unit 17 and the close-up video image on the self side is sent to the line 13 and transmitted to the other side. At this time, the image on the display unit 16 on the self side is switched to the image sent from the videophone device on the other side. If the enlarged display function is limitedly used only on the self side on the assumption that the videophone device on the other side is not remotely controlled, the D interface section 20 of the transmission / reception section 11 becomes unnecessary.

As described above, the resolution converter 27 calculates the number of samples and the sampling frequency in order to sample the luminance signal and the chrominance signal according to the enlargement frame shown. The calculation method will be described with reference to FIGS. 5. The layout will be described with reference to the schematic diagram showing the enlargement processing of the videophone device in the fifth embodiment of the present invention.

4 to 5, the portion surrounded by the horizontal synchronizing signal corresponds to one field of the display screen.
In FIG. 4 showing the standard display screen, the display range is M and the number of samples is N. In FIG. 5 showing the enlarged display screen, the display range is m,
Let n be the number of samples. Even if the display range is reduced from M on the standard display screen to m on the enlarged display screen, if the number of samples is the same for both the standard display screen and the enlarged display screen, N = n, the sampling frequency is N / M of the standard display screen. From the enlarged display screen N
/ M. Then, the HCI standard QCI
It is possible to close up the enlarged frame portion from the standard display screen while maintaining the resolution of 176 × 144 dots or more, which is the F format. However, due to the restriction on the processing speed of the A / D conversion unit 4, the actual expansion range is limited from the theoretical value described in FIG.

As described above, the video telephone device of the present invention is
By performing image processing, the screen can be enlarged and displayed while maintaining the resolution. Moreover, since it is possible to magnify and display any part of the screen, it is superior to the case of using a zoom lens that can magnify only the central part. In addition, since the image pickup unit can be configured with a single-focus lens having a small number of components, it is possible to promote size reduction and weight reduction and cost reduction.

[0033]

According to the videophone device of the present invention, the camera section for digitizing the image data and the audio data generated by the image pickup section and the handset by the A / D conversion section, and the data from the camera section are compressed by the codec section. After that, an image processing unit that multiplexes image data and audio data to generate video data,
An enlarging processing unit that converts the resolution of the enlarging range specified by the enlarging range specifying unit by the resolution converting unit, a transmitting / receiving unit that outputs the video data to the line, a display unit that outputs the data from the image processing unit as an image, and various The enlargement processing unit converts the resolution in the A / D conversion unit before the compression processing in the codec unit.

With this configuration, the compression process in the codec unit inevitably involves a decrease in resolution, but the expansion process can be performed at a high resolution stage before that. Therefore, even if the image is enlarged and displayed in close-up by image processing without using the zoom lens, the normal resolution can be maintained after the compression processing.

[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 schematic diagram showing a change in resolution of a videophone device according to an embodiment of the present invention.

FIG. 3 is a schematic diagram showing a call state in a videophone device according to an embodiment of the present invention.

FIG. 4 is a schematic diagram showing enlargement processing of a videophone device according to an embodiment of the present invention.

FIG. 5 is a schematic diagram showing enlargement processing of a videophone device according to an embodiment of the present invention.

FIG. 6 is a block diagram showing a configuration of a conventional videophone device.

FIG. 7 is a schematic diagram showing a call state in a conventional videophone device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Imaging unit 2 Encoder 3 Handset 4 A / D conversion unit 5 Memory 6 Camera unit 7 Image processing unit 8 Codec unit 9 Memory 10 Multiplexing / separating unit 11 Transmitting / receiving unit 12 Interface unit 13 Line 14 Memory 15 D / A conversion unit 16 Display Part 17 Operation part 18 CPU 19 Main part 20 D interface part 21 Imaging part 22 Camera part 23 Image processing part 24 Main part 25 Enlargement processing part 26 Enlargement range designation part 27 Resolution conversion part A area B area C area D area

Claims (4)

[Claims] 1. A camera unit for digitally processing an image signal and an audio signal generated by an image pickup unit and a handset in an A / D conversion unit, a codec unit for compressing data from the camera unit, and a compression in the codec unit. An image processing unit having a multiplexing / separating unit that multiplexes processed image data and audio data to generate video data and separates the video data into image data and audio data, and a display screen of the display unit. An enlarging processing unit having an enlarging range designating unit for managing the enlarging and displaying range as coordinate data, and a resolution converting unit for converting the resolution of the enlarging range designated by the enlarging range designating unit to the resolution after enlarging, A transmission / reception unit that inputs / outputs data to / from the line, a display unit that outputs data from the image processing unit as an image, an operation unit that allows the user to perform various operations, and the control of the entire device. A videophone apparatus that includes a CPU for the enlargement processing unit videophone apparatus characterized by converting the resolution before the compression process by the codec unit. 2. The video telephone apparatus according to claim 1, wherein the enlargement processing unit converts the resolution after digital processing is performed by the A / D conversion unit. 3. The videophone device according to claim 1, wherein the enlargement processing unit converts the resolution by operating the self-side terminal device. 4. The videophone device according to claim 1, wherein the enlargement processing unit converts the resolution by operating the terminal device on the self side or the partner side.