KR20030028214A - Image data communication system capable of reducing bandwidth of image data for transmitting - Google Patents

Abstract

Disclosed is a video data transmission / reception system capable of reducing a frequency bandwidth of video data for transmission. The image data transmission / reception system converts and transmits a digital image signal, which is reproduction data output by reproducing and outputting image data from a recording medium and / or recording data photographing a subject through a camera, and converting the digital image signal transmitted serially. In the video data transmission and reception system for receiving and converting to parallel to restore the original signal, the video data transmission / reception system performs compression to remove a predetermined horizontal signal and / or vertical signal from the digital video signal, and converts the compressed digital video signal to serial. An image data transmission device and an image data reception device for receiving a compressed digital video signal, restoring a horizontal signal and / or a vertical signal removed in accordance with compression, and converting the restored digital video signal to parallel. By performing compression on the digital video signal through the image data transmission device, serial transmission is performed, and by receiving the digital video signal transmitted serially through the image data receiving device to decompress and restore the original signal, It is possible to reduce the bandwidth of the sampling frequency required to transmit.

Description

Image data communication system capable of reducing the frequency bandwidth of the image data for transmission {Image data communication system capable of reducing bandwidth of image data for transmitting}

The present invention relates to an uncompressed video data transmission and reception system, and more particularly, to a non-compressed video data transmission device for transmitting digital video data in an uncompressed form and a video data reception device for receiving digital video data in an uncompressed form. The present invention relates to a compressed video data transmission / reception system.

As full-scale information enters the market, the recent trend of technological development has been compounding and digitizing the external display products that display audio / video products and audio / video data output from the audio / video products. Accordingly, the recent image data transmission and reception system is required to transmit and receive high-quality image signal and simple operation. In particular, recently, with the development of semiconductor technology, digital video cameras using digital signal technology have been developed and released. Such digital video cameras are being installed in premises such as banks, schools, apartments, homes, etc., replacing conventional closed circuit television systems (CCTV systems).

The format of digital image data through a digital camera is subject to the international telecommunication union-radiocommunication sect (ITU-R) standard. The ITU-R standard specifies that reproduction and restoration of image data except for an output terminal (not shown) and an input terminal (not shown) for image data are performed through an 8-bit interface. Accordingly, in order to transmit image data according to the ITU-R standard, 8 bits are converted into serial and transmitted in units of 1 bit.

Referring to the output of a video signal through a digital camera using the ITU-R601 as an example, a wireless communication standard such as the ITU-R601 has a sampling frequency of a predetermined bandwidth (bandwidth). At this time, the ITU-R601 has a bandwidth of 27 [MHz]. In order to apply the frequency band to image data transmission and reception such as serial wireless communication, a sampling frequency for communication of 216 [MHz] band is required.

1 is a block diagram schematically illustrating a conventional image data transmission and reception system. According to the drawing, the transmitting end is provided with a serial converter 2 for converting 8-bit image data in units of 1 bit and a transmitter 4 for transmitting serially converted image data to an external device by wire and / or wirelessly. . At this time, the image data transmitted from the transmitter 4 is transmitted in units of 1 bit, and thus the image data transmitted from the transmitter 4 has a high sampling frequency band.

In addition, the receiving end has a receiving unit 6 for receiving high frequency image data in units of 1 bit and a parallel converting unit 8 for converting the received image data from serial to parallel. The video data converted to parallel is restored to the original signal at the rear end of the parallel converter 8. At this time, in order to restore the original signal, the original signal is restored through frequency synchronization with respect to the image data.

Such image data transmission and reception system is required for the overall accuracy according to the transmission and reception of high frequency. Accordingly, the conventional video data transmission / reception system requires a high performance video data transmission device and a reception device capable of responding to high frequencies in detail. Such a high performance image data transmitter and receiver are factors that increase the production cost for producing a product. In addition, conventional image data transmitters and receivers require higher accuracy due to higher frequencies when performing phase synchronization of frequencies.

In order to solve this problem, spatial redundancy of image data is removed by using a transform coding of a discrete cosine transform (DCT) in an image data encoder (not shown) of a transmitting side of a conventional image data transmission / reception system. In addition, the method may be applied by compressing the video signal by removing temporal redundancy of the video signal by using differential encoding through motion estimation and prediction on the video data. However, such compression requires an encoder and a decoder in an image data transmission / reception system, and a memory having a larger capacity than a conventionally required memory capacity is required to perform abnormal cosine conversion.

An object of the present invention for solving the above problems, when transmitting and receiving high-frequency image data through serial conversion, by simply compressing the image data of a specific format by lowering the band of the sampling frequency required for the predetermined image data image An object of the present invention is to provide an image data transmission / reception system that can reduce a data transmission / reception burden.

1 is a block diagram schematically showing a conventional image data transmission and reception system;

2 is a block diagram schematically illustrating an image data transmission / reception system capable of reducing a frequency bandwidth of image data for transmission according to the present invention; and

3 is a flowchart illustrating a video data transmission / reception method for reducing the frequency bandwidth of video data for transmission according to the present invention.

Explanation of symbols on the main parts of the drawings

10: image data compression unit 20: serial converter

30: transmitter 40: receiver

50: extending unit 60: restoring unit

In order to achieve the above object, an image data transmission / reception system capable of reducing a frequency bandwidth of image data for transmission according to the present invention may be performed by reproducing image data from image data and / or recording media photographing a subject through a camera. A video data transmission / reception system for converting a digital video signal, which is output data, to be converted into serial data, and receiving a digital video signal transmitted in serial and converting it to parallel to restore an original signal. And / or an image data transmission device which converts a compressed digital video signal into serial by performing compression to remove vertical signals, and horizontal signals and / or vertical signals which are removed according to compression by receiving compressed digital video signals. Video to convert the restored digital video signal to parallel And a receiver receiver.

Preferably, the image data output apparatus may perform compression by removing data that is not necessary to display the digital image signal through a display unit provided in the image data receiving apparatus. In addition, the image data output apparatus may perform compression by DPCM, VLC, and RLC, or may perform compression by run length combination by removing a blank section of a digital image signal.

On the other hand, the image data transmission and reception method which can reduce the frequency bandwidth of the image data for transmission in accordance with the present invention for achieving the above object, the image data from the image pickup data and / or recording medium photographed the subject through the camera A video data transmission / reception method for converting a digital video signal, which is reproduced and outputted data, by converting it into a serial signal, receiving a digital video signal transmitted through a serial signal, converting the signal into a parallel signal, and restoring the original signal. Performing compression to remove horizontal and / or vertical signals; converting and transmitting a compressed digital video signal to serial; receiving and receiving a compressed digital video signal and removing the horizontal and / or vertical signals. Restoring the data, and converting the restored digital video signal to parallel. Characterized in that.

Preferably, the compressing step may perform compression by removing data that is not necessary to display the digital video signal on the external device. Also, the compression step may perform compression by DPCM, VLC, and RLC. On the other hand, the compression step may perform compression by run length combination by removing the blank section of the digital video signal.

According to the present invention, a serial transmission is performed by compressing a digital video signal through a video data transmission device, and a digital video signal transmitted to a serial is received through a video data receiver to cancel compression and restore the original signal. By doing so, the bandwidth of the sampling frequency required for transmitting the image data can be reduced.

Hereinafter, the present invention will be described in detail with reference to the drawings.

2 is a block diagram illustrating a video data transmission / reception system capable of reducing a frequency band of video data for transmission according to the present invention. The image data transmission / reception system according to the drawing includes an image data compression unit 10, a serial converter 20, a transmitter 30, and a receiver 40 and an extension unit corresponding to the image data receiver. 50, the restoration part 60 is provided.

The image data compression unit 10 compresses the image data by removing a predetermined horizontal signal and / or a vertical signal of the image data input through the 8-bit interface. At this time, when the image data is compressed through the image data compression unit 10, the frequency bandwidth for the image data is reduced, thereby lowering the sampling frequency. The serial converter 20 serially converts 8-bit compressed image data in 1-bit units. The transmitter 30 transmits the serially converted image data to an external device by wire and / or wirelessly. At this time, the image data transmitted from the transmitter 30 is transmitted in units of 1 bit, and the frequency bandwidth of the image data transmitted in this way is reduced by half compared to the frequency bandwidth before compression. Meanwhile, when the transmission channel is wireless, the transmission unit 30 means an antenna (not shown) for transmitting image data in the air, and when the transmission channel is wired, a cable for transmitting image data ( Means a communication interface (not shown) to be connected to (not shown).

Accordingly, it is possible to reduce the product cost burden due to the accuracy of the synchronization unit (not shown) required for frequency synchronization and the amplification oscillator (not shown) required for amplifying the sampling data for image data.

Meanwhile, the receiver 40 of the image data receiving end receives the image data serially transmitted in 1-bit units through wired and / or wireless. In this case, the receiver 40 means an antenna (not shown) when the transmission channel of the image data transmitted through the transmitter 30 is wireless, and when the transmission channel of the image data is wired, the receiver and the receiver are connected. Means a communication interface (not shown) provided to be connected to the connecting cable (not shown). The decompression unit 50 restores the removed vertical signal and / or the horizontal signal with respect to the image data received by 1 bit. The reconstruction unit 60 converts serial image data in 1-bit units into parallel in 8-bit units. At the rear end of the restoring unit 60, the parallel-converted image data is restored to the original signal and processed according to the operation of the image data receiving apparatus.

Accordingly, the image data receiving end performs a reconstruction operation on the image data corresponding to the low frequency band, thereby providing high accuracy for the synchronizer (not shown) and the amplifier (not shown) necessary for frequency synchronization and amplification of the image data. Does not cost. Therefore, in the production of the product, the cost can be reduced.

Meanwhile, when the transmitter 30 transmits the image data, the image data compression unit 10 of the transmitting end encodes the image data using spatial and temporal correlation of the image data, and then transmits the image data to the receiver 40 through a limited transmission channel. Perform compression. In the compression of the image data compression unit 10 according to the present embodiment, a number of methods have been proposed for effectively compressing and transmitting digital image signals such as image data. Among them, discrete cosine is applied to a differential pulse code modulation (DPCM) encoding method. It is desirable to use a high efficiency coding technique that properly combines transform coding such as Discrete Cosine Transform and variable length coding (VLC).

On the other hand, the image data compression unit 10 is an image that is not necessary to be displayed on an external display device (not shown) for the image data captured and reproduced through a camera (not shown) and / or a digital video signal player (not shown) You can also perform compression by removing data. At this time, the image data compression unit 10 compresses by removing 1 to 15 lines and 236 to 254 lines (hereinafter, referred to as blank sections) that are not related to displaying image data among the vertical and horizontal signal lines of the image data. Can be performed. Meanwhile, the image data compression unit 10 may perform compression using run length coding (RLC) for the blank section.

Meanwhile, the image data compression unit 10 may perform compression by applying DPCM, VLC, and RLC to the image data, respectively.

Accordingly, the image data transmitting and receiving apparatus according to the present embodiment can reduce the accuracy of the synchronization unit and / or amplification unit required for the product by reducing the frequency bandwidth by half to a high sampling frequency necessary for transmitting and receiving high image data. . Accordingly, the cost required for producing the product can be reduced.

3 is a flowchart illustrating a method of transmitting / receiving image data capable of reducing a frequency band of image data for transmission according to the present invention. Referring to the drawings, first, when image data captured and reproduced through a camera and / or a digital image signal is input to the image data compression unit 10, the image data compression unit 10 is applied to the image data input with 8 bits. Compression is performed (S10). In this compression method, DPCM, VLC, RLC and the like can be applied. When the 8-bit image data is compressed in S10, the serial converter 20 performs serial conversion of the compressed 8-bit image data in units of 1 bit (S20). At this time, the transmission unit 30 transmits the image data converted into a 1-bit serial to the receiving unit 40 of the receiving end by wire and / or wireless.

On the other hand, for the image data transmitted by S20, the receiver 40 and the decompression unit 50 receives the image data transmitted in units of 1 bit through the antenna and / or interface, and compress the compressed image data An expansion operation of removing is performed (S30). At this time, the decompression operation of the decompression unit 50 is an image data format before being compressed by the image data compression unit 10, and is only serial image data in units of 1 bit. On the other hand, with respect to the decoded 1-bit image data, the reconstructor 60 converts the 1-bit image data to 8-bit unit parallel (S40). At this time, the restoration unit 60 restores the image data converted to parallel to the original signal through the 8-bit interface and transmits the image data to the signal processing unit (not shown) which performs the corresponding operation. The signal processor restores the 8-bit image data to the original signal to be displayed on a screen (not shown) (S50).

Therefore, the burden of the frequency bandwidth on the image data can be reduced, and accordingly, there is an effect of cost reduction in product production.

In this embodiment, compression of the image data output through the camera and the digital image signal player is performed to reduce the signal processing burden according to the bandwidth of the sampling frequency, but the digital image signal is wired and / or wirelessly to an external device. The above-described embodiments may be equally applied to a transmission electronic device.

According to the present invention, before the digital image data is converted into serial through the image data transmitting apparatus and transmitted to the image data receiving apparatus, the image data transmitting apparatus performs compression to reduce the sampling frequency bandwidth for the digital image data. By converting the image data to serial and transmitting the image data to the image data receiving apparatus, transmission and reception of image data requiring a high frequency band is possible.

In addition, according to the present invention, by performing the compression to lower the frequency band for a high frequency through the image data transmission and reception to transmit and receive the image data, the burden on the accuracy of the synchronization unit (not shown) to synchronize the sampling frequency It can reduce the cost of producing the product.

In the above described and described with respect to the preferred embodiment of the present invention, the present invention is not limited to the specific preferred embodiment described above, in the technical field to which the invention belongs without departing from the spirit of the invention claimed in the claims Various modifications can be made by those skilled in the art, and such changes are within the scope of the claims.

Claims (12)

Converts and transmits a digital image signal, which is reproduction data output by reproducing image data from a recording medium and / or recording data photographing a subject through a camera, and receiving and converting the digital image signal transmitted serially to parallel. In the video data transmission and reception system for restoring the original signal, A video data transmission device for performing compression to remove a predetermined horizontal signal and / or vertical signal from the digital video signal, converting the compressed digital video signal into a serial, and transmitting the serial signal; And And a video data receiving device for receiving the compressed digital video signal, restoring the horizontal signal and / or the vertical signal removed according to compression, and converting the restored digital video signal to parallel. Image data transmission and reception system. The method of claim 1, And the video data transmission device performs compression by removing data that is not necessary to display the digital video signal through a display unit provided in the video data receiving device. The method of claim 1, And the image data transmission device performs compression by DPCM. The method of claim 1, And the image data transmission device performs compression by VLC. The method of claim 1, And the image data transmission device performs compression by RLC. The method of claim 1, And the image data transmission device performs compression by run length combination by removing the blank section of the digital image signal. Converts and transmits a digital image signal, which is reproduction data output by reproducing image data from a recording medium and / or recording data photographing a subject through a camera, and receiving and transmitting the digital image signal transmitted in the serial to parallel In the video data transmission and reception method for converting and restoring to an original signal, Performing compression to remove a predetermined horizontal signal and / or vertical signal from the digital video signal; Converting and compressing the compressed digital video signal into the serial; Receiving the compressed digital video signal and restoring the horizontal signal and / or the vertical signal removed according to compression; And And converting the reconstructed digital video signal to parallel. The method of claim 7, wherein And the compressing step performs compression by removing data that is not necessary to display the digital video signal on an external device. The method of claim 7, wherein The compression step is a video data transmission and reception method, characterized in that for performing compression by DPCM. The method of claim 7, wherein The compressing step is a video data transmission and reception method, characterized in that for performing compression by VLC. The method of claim 7, wherein The compressing step is a video data transmission and reception method, characterized in that for performing compression by RLC. The method of claim 7, wherein And the compression step removes the blank section of the digital video signal and performs compression by run length combination.