JP2001016492A - Digital video camera - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a digital video camera by which a high speed encoding function and a high speed decoding function can be utilized by external equipment including PC. SOLUTION: The digital video camera is provided with an image pickup part 2 for converting visual information into a digital video signal, an image encoding part 3 for selecting the digital video signal outputted from the image pickup part and the digital video signal inputted from the outside and data- compressing the selected digital video signal, a recording part 4 for recording the data-compressed digital video signal and an output part for outputting the digital video signal outputted from the image encoding part 5 to the outside. Thus, the image encoding means of the digital video camera is utilized by external equipment.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to image data compression and image compression.
The present invention relates to a digital video camera which records and reproduces an image by decompression, and in particular, its image data compression function or image data.
The present invention relates to a digital video camera capable of using an external device with a data expansion function.

[0002]

2. Description of the Related Art In recent years, digital video cameras capable of recording and reproducing moving images in digital form have become widespread. In these video cameras, if moving image data is recorded as it is, the amount of data is large, and it cannot be stored on a recording medium with a limited recording density (total recording amount). And perform some kind of video coding (compression) with the product. As a compression method, the DV method is most often used, but recently, MPEG (Moving P
title Coding ExpertsGrou
Products that perform compression according to p) -2 or MPEG-4 are also available. These products enable editing operations by exchanging compressed image data by connecting to a personal computer (hereinafter, referred to as PC), and recording / reproduction of digital video cameras. Some of them accept operations from outside.

[0003] In any case, the moving picture coding (compression) devices of these digital video cameras can use only the image taken from the imaging section as an input. For this reason, the high-speed encoding function for compressing a moving image can be used only when recording as a camera, and other devices such as a PC cannot use the function. This is considered to be because only the function as the digital video camera was considered.

Further, the exchange of image data between the digital video camera and the external device is performed in a compressed form. However, regarding this exchange, if the interface to be used is selected, the compressed form is exchanged. The restriction of limiting is gone. That is, for example, IEEE (Institute of Technology) which is an interface standard for digital image data.
Electronic and Electroni
cEngineering) 1394 is up to 400M
The transfer of bps (bits / second) is specified, and it is possible to transfer an image which is not compressed as an image.

[0005]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has been made to enhance the added value of a digital video camera. An object of the present invention is to provide a digital video camera that can use the digital video camera.

[0006]

In order to solve the above-mentioned problems, the present invention provides imaging means for converting visual information into a digital video signal, a digital video signal output from the imaging means and a digital signal input from the outside. Image encoding means for selecting a video signal and data-compressing the selected digital video signal, recording means for recording the data-compressed digital video signal, and digital video output from the image encoding means Means for outputting a signal to the outside.

Thus, the external device can use the image encoding means of the digital video camera.

[0008] Further, imaging means for converting visual information into a digital video signal, image encoding means for data-compressing the digital video signal output from the imaging means, and recording the data-compressed digital video signal. Recording means, image decoding means for selecting a digital video signal read from the recording means and an externally input data-compressed digital video signal and decompressing the selected digital video signal, Means for externally outputting a digital video signal output from the image decoding means.

Thus, the external device can use the image decoding means of the digital video camera.

[0010] Further, an image pickup means for converting visual information into a digital video signal, a digital video signal output from the image pickup means and a digital video signal inputted from the outside are selected, and the selected digital video signal is selected. Image encoding means for compressing data, recording means for recording the data-compressed digital video signal, digital video signals read from the recording means and data-compressed digital video signals inputted from the outside Image decoding means for expanding the data of the selected digital video signal upon selection of the digital video signal, means for outputting the digital video signal output from the image coding means to the outside, and output from the image decoding means Means for outputting a digital video signal to the outside.

Thus, the external device can use both the image encoding means and the image decoding means of the digital video camera.

[0012] Further, it is characterized in that it further comprises means for inputting a control signal for controlling the operation, and means for controlling the operation in accordance with the input control signal.

Thus, the digital video camera can perform the above-described desired operation under the control of an external device.

[0014]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a diagram showing a configuration of a digital video camera according to an embodiment of the present invention and a configuration in a case where an external device uses some functions of the camera.

As shown in FIG. 1, this configuration includes a digital video camera 1 and an external device 11.

The digital video camera 1 has an imaging unit 2, an image encoding unit 3, a data recording unit 4, an image decoding unit 5, an image display unit 6, and an interface connection unit 7.

The imaging unit 2 converts optical information, which is an input image, into electrical information, digitizes the electrical information to generate a digital video signal, and supplies the digital video signal to the image encoding unit 3. The image encoding unit 3 compresses the supplied digital video signal, and if the input image is a moving image, the data rate is reduced. Data compression methods include DV, MPEG-2, and MPE.
G-4 or the like can be used.

The data recording section 4 records the data-compressed digital video signal on a recording medium. As a recording medium, a semiconductor memory such as a flash memory can be used in addition to a video tape. The data recording section 4 also performs an operation for reading recorded data, that is, a reproducing operation in the case of a video tape.

The image decoding section 5 performs an operation of restoring the compressed video signal reproduced or read by the data recording section 4, that is, data expansion.

The image display section 6 displays on the screen what has been decompressed and converted into the original digital video signal. Specifically, it is a liquid crystal display, etc.
It is also possible to provide an output terminal to an external display.

The interface connection unit 7 exchanges a video signal with an external device, and furthermore, the digital video camera 1
Under the control of an external device, accepts a control signal for external operation, and outputs a response to the external device. As the output of the video signal, in the case of a compressed signal, there are a case where the video signal is output from the image encoding unit 3 and a case where the data is output from the data recording unit 4. Similarly, the output from the image decoding unit 5 is not compressed. The input of the video signal is to the image decoding unit 5 in the case of the compressed one. Similarly, when the image is not compressed as an input, the processing is to the image encoding unit 3.

The interface standard is I
EEE1394, USB (universal ser
Other than the above, a wireless interface such as Bluetooth (trademark) can be used.

The external device 11 is, for example, a PC, and includes an interface connection unit 12, a camera control unit 13, a data recording unit 14, and a display unit 14.

The interface connection unit 12 exchanges video signals with the digital video camera 1 and outputs control signals for operating the digital video camera 1 from the external device 11 under the control of the external device 11. The response is received from the digital video camera 1.

The camera control section 13 controls the digital video camera 1. Specifically, for example, a CPU (central processing) in a PC
unit) and software for controlling the camera.

The data recording section 14 records data, and is specifically a hard disk or the like.

The display section 15 displays information necessary for the external device 11, and is a CRT (cathode mode).
(ray tube) display or a liquid crystal display is used.

Next, the operation of this embodiment will be described.

First, as an example, a case in which uncompressed moving image data stored in the data recording unit 14 of the external device 11 is compressed using the digital video camera 1 and stored again in the data recording unit 14 will be described. .

The processing flow in this case is roughly described as follows.
First, the external device 11 and the digital video camera 1 make a request and response to start data transfer, then, in the data transfer mode, actually transfer moving image data, and finally make a request and response to end data transfer. Procedure.

The flow of these operations will be described with reference to the flowcharts of FIGS. The operation of the external device 11 is as shown in FIG. In FIG. 3, the left side shows the entire flow, and the right side shows the data transfer mode which is a part of the whole.

That is, the operation of the external device 11 is as follows.
A data transfer start request is issued to the camera-side interface (step S31), and a response is waited for (step S3).
2). When the transfer start response arrives, the mode shifts to the data transfer mode (step S33).

In the data transfer mode, the data recording unit 14
First, the moving image data read from is transferred to the camera-side interface (step S331), and then the compressed data from the camera-side interface is waited for (step S33).
2). When the compressed data arrives, the data is fetched (step S333), written to the data recording unit 14, and
It is determined whether or not the data has been captured (step S
334). If not, the process returns to the beginning of the data transfer mode. If not, the data transfer mode ends.

Finally, the external device 11 outputs a data transfer end request (step S34), and waits for a response (step S35). When the transfer end response arrives, all processing ends.

The operation of the digital video camera 1 in response to the operation procedure of the external device 11 is as shown in FIG. In FIG. 2, the one on the left shows the entire flow, and the one on the right shows the data transfer mode, which is a part of the whole.

That is, the digital video camera 1 first waits for a data transfer start request sent from the interface of the PC as the external device 11 (step S2).
1). When the request arrives, a data transfer start response is output (step S22), and the mode shifts to the data transfer mode (step S23).

In the data transfer mode, first, the transfer of image data from the PC side interface is waited (step S2).
31) When the image data arrives, the image data is fetched and transferred to the image encoding unit 3 (step S232). Here, the image encoding (data compression) is performed in real time, and then the output is awaited (step S233). When the compressed data is output and arrives, the compressed data is transferred to the PC side interface (step S234). Here, it is determined whether a transfer end request has arrived (step S235). If it has not arrived, the process returns to the beginning of the data transfer mode, and if it has arrived, the data transfer mode is ended.

Finally, a data transfer end response is output (step S24), and all processing ends.

As described above, in this example, the PC which is the external device 11 can compress the moving image data using the digital video camera 1.

Next, as another example, a case in which a video image taken by the digital video camera 1 is compressed into a moving image and taken into the external device 11 to perform real-time moving image communication (for example, in the case of a videophone) Will be described.

The processing flow in this case is roughly described as follows.
As in the above-described example, first, the external device 11 and the digital video camera 1 perform a data transfer start request and response, and
Next, in the data transfer mode, the moving image data is actually transferred, and finally, a request and response to the end of the data transfer are made.

The flow of these operations will be described with reference to the flowcharts of FIGS. The operation of the external device 11 is as shown in FIG. In FIG. 5, the one on the left shows the entire flow, and the one on the right shows the data transfer mode which is a part of the whole.

That is, the operation of the external device 11 is as follows.
A data transfer start request is issued to the camera-side interface (step S51), and a response is waited for (step S5).
2). When the transfer start response arrives, the mode shifts to the data transfer mode (step S53).

In the data transfer mode, first, compressed data of a moving image from the camera side interface is waited for (step S531), and when the compressed data arrives, the data is taken in (step S532). Then, it is determined whether or not the data has been captured (step S533). If not, the process returns to the beginning of the data transfer mode. If not, the data transfer mode ends. Data is stored in external device 1
1 is transmitted to a communication function unit (not shown) or a mobile phone, thereby realizing video communication, that is, a videophone.

Finally, the external device 11 outputs a data transfer end request (step S54), and waits for a response (step S55). When the transfer end response arrives, all processing ends.

The operation of the digital video camera 1 with respect to the operation procedure of the external device 11 is as shown in FIG. In FIG. 4, the one on the left indicates the entire flow, and the one on the right indicates the data transfer mode which is a part of the whole.

That is, the digital video camera 1 first waits for a data transfer start request sent from the interface of the PC as the external device 11 (step S4).
1). When the request arrives, a data transfer start response is output (step S42), and the mode shifts to the data transfer mode (step S43).

In the data transfer mode, first, a timer interrupt is waited for (step S431). When the interrupt occurs, the image of the image pickup unit 2 is captured and transferred to the image encoding unit 3 (step S432). Here, the image encoding (data compression) is performed in real time, and then the output is awaited (step S433). P when compressed data is output and arrives
It waits for a data transfer completion response from the C-side interface (step S434). When the completion response arrives, it is determined whether a transfer end request has arrived (step S435).
If it has not arrived, it returns to the beginning of the data transfer mode, and if it has arrived, the data transfer mode is ended.

Finally, a data transfer end response is output (step S44), and all processing ends.

In this case, as an example, a timer-interrupt is generated, and an image captured by the timer-interrupt is output to the image encoding unit 3.
And the data transfer completion response is received from the interface of the PC, which is the external device 11, and the minimum processing is terminated. Of course, the digital video camera 1 is completely It is also possible to operate under the control of.

As described above, in this example, the PC as the external device 11 can realize real-time video communication such as a videophone using the imaging function and the video compression function of the digital video camera 1. it can.

In this case, MPEG-4 is generally used as a moving image compression method in accordance with the standard of moving image communication. Therefore, the interface between the digital video camera 1 and the external device 11 is low. USB, which is a data rate standard, can be used. Further, this interface may be a wireless interface such as Bluetooth (trademark).

Next, as another example, a case will be described in which a video material shot by the digital video camera 1 and recorded in the data recording unit 4 is edited by the external device 11.

The compressed moving image data recorded in the data recording unit 4 is reproduced or read out and sent to the image decoding unit 5. Here, the data is expanded to become the original digital video signal, which is guided to the interface connection unit 7. Further, the data is transferred to the interface connection unit 12 of the external device 11 and recorded in the data recording unit 14 via the camera control unit 13.

In the external device 11, the data recording unit 1
4 is edited, and the edited image data is recorded in the data recording unit 14. Since uncompressed data is used in this editing, it can be clearly displayed on the display unit 15 as an image even during editing.

The edited image data recorded in the data recording unit 14 is supplied to the image encoding unit 3 via the camera control unit 13 and the interface connection units 12 and 7 to be compressed and recorded in the digital video camera 1. Recorded again in section 4.

In this example, when editing is performed on the external device 11, the external device 11 encodes and encodes a moving image.
It is not necessary to prepare a codec device for performing decoding (compression / decompression) processing. Also, there is no need to perform compression / decompression by software, and the CPU load is reduced.

In this example, the exchange of moving image data between the digital video camera 1 and the external device 11 uses an uncompressed one at a high data rate.
This can be realized using the EE1394 standard.

In addition to the above-described example, similarly, for example, the compressed image data recorded in the data recording unit 14 is supplied to the image decoding unit 5 via the camera control unit 13 and the interface connection units 12 and 7. Image display section 6
Can also be displayed. Also in this case, the compressed moving image data can be reproduced as the original image without placing a burden on the external device 11.

[0061]

As described in detail above, according to the present invention,
The input and output of the image encoding unit (data compression unit) or image decoding unit (data decompression unit) inside the digital video camera can be connected to the outside, so that these can be used for external devices. Become. This eliminates the need for the external device to prepare a new moving picture codec device, and also eliminates the burden of performing compression / decompression by software.

Further, since the control signal of the external device can be input, the above-mentioned desired operation can be performed under the control of the external device.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration of an embodiment of the present invention.

FIG. 2 is a flowchart showing an operation example of the digital video camera in the embodiment of FIG.

FIG. 3 is a flowchart showing an operation example of an external device in the embodiment of FIG. 1;

FIG. 4 is a flowchart showing another operation example of the digital video camera in the embodiment of FIG. 1;

FIG. 5 is a flowchart showing another operation example of the external device in the embodiment of FIG. 1;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Digital video camera 2 Imaging part 3 Image encoding part 4 Data recording part 5 Image decoding part 6 Image display part 7 Interface connection part 11 External equipment 12 Interface connection part 13 Camera control part 14 Data recording part 15 Display part

Claims (4)

[Claims] An imaging unit for converting visual information into a digital video signal, a digital video signal output from the imaging unit and a digital video signal input from the outside selected, and the selected digital video signal is selected. Image encoding means for compressing data, recording means for recording the data-compressed digital video signal, and means for externally outputting a digital video signal output from the image encoding means. Digital video camera. 2. An imaging unit for converting visual information into a digital video signal, an image encoding unit for compressing the digital video signal output from the imaging unit, and a recording of the data compressed digital video signal. Recording means, image decoding means for selecting a digital video signal read from the recording means and a data compressed digital video signal input from the outside, and decompressing the selected digital video signal, Means for externally outputting a digital video signal output from said image decoding means. 3. An image pickup means for converting visual information into a digital video signal, a digital video signal outputted from the image pickup means and a digital video signal inputted from the outside selected, and the selected digital video signal is selected. Image encoding means for compressing data; recording means for recording the data-compressed digital video signal; digital video signals read from the recording means and data-compressed digital video signals inputted from outside; Image decoding means for expanding the data of the selected digital video signal upon selecting the digital video signal; means for outputting the digital video signal output from the image encoding means to the outside; output from the image decoding means Means for outputting a digital video signal to an external device. 4. The digital video camera according to claim 1, further comprising: a unit for inputting a control signal for controlling an operation; and a unit for controlling an operation based on the input control signal. The digital video camera according to any one of claims 1 to 3, comprising: