KR19990058511A - Digital video signal recording / playback device - Google Patents

Abstract

The digital video signal recording / reproducing apparatus of the present invention separates horizontal and vertical sync signals from sequentially input video signals from switching means for sequentially converting video signals input from one or more video cameras on a field or frame basis, and displays luminance and color differences. A decoder for separating the signal and converting the luminance and chrominance signals into a digital signal; A codec for compressing the digital signal read out from the decoder or extending the compressed digital signal; A digital signal recorder storing a digital signal compressed by the codec; A system controller which controls the whole system and converts the compressed data into a file format in order to preserve the digital signal compressed by the codec as a file in the digital signal recording unit; A memory unit for temporarily receiving a digital signal from the codec for receiving and compressing compressed data stored in the digital signal recording unit; A memory control unit controlling timing of writing and reading of the memory unit; An encoder for converting the digital signal read from the memory unit into an analog signal and receiving the sync signal into a composite video signal; And a video output unit configured to output the composite video signal converted by the encoder to a split screen or a single screen.

Description

Digital video signal recording / playback device

The present invention relates to a digital video signal recording / reproducing apparatus, and more particularly, to convert a video signal input from one or more video cameras into a digital video signal and to store it in a hard disk so as to provide a high quality video signal. A digital video signal recording / reproducing apparatus.

In general, Closed Circuit Tele-Vision (hereinafter referred to as CCTV) system is installed in general houses, department stores, banks, factories, parking lots, and exhibition halls to prevent theft and prevent the operation of the machine or process flow. It is a device that is widely used for surveillance that can be easily checked and used to identify traffic conditions at major intersections. Such a CCTV system captures images taken from one or more video cameras or video cameras that capture surveillance objects. It consists of a monitor that outputs to the screen and a VCR that records the images shot by the video camera for later playback.

In the conventional CCTV system as described above, analog video signals input from one or more cameras are divided into horizontal and vertical sync signals and luminance and chrominance signals, and the luminance and chrominance signals are converted into digital signals and then converted into analog signals. After that, the horizontal and vertical synchronization signals and the luminance and color difference signals converted into analog signals were synthesized into video signals and recorded on the VCR. When the recorded video signal is reproduced, the analog video signal is reproduced as in the recording.

Therefore, conventionally, there is a problem in that image quality deteriorates due to frequent signal conversion.

Disclosure of Invention The present invention has been made to solve the above-described problem, and digital video signal recording is provided to convert a video signal input from one or more video cameras into a digital video signal and store the image signal on a hard disk to provide a high quality video signal. It is an object to provide a playback device.

The digital video signal recording / reproducing apparatus of the present invention for achieving the above object is a horizontal and vertical synchronization in the video signal sequentially input from the switching means for sequentially switching the video signal input from one or more video cameras in field or frame units A decoder which separates the signal and separates the luminance and the chrominance signal into a digital signal; A codec for compressing the digital signal read out from the decoder or extending the compressed digital signal; A digital signal recorder storing a digital signal compressed by the codec; A system controller which controls the whole system and converts the compressed data into a file format in order to preserve the digital signal compressed by the codec as a file in the digital signal recording unit; A memory unit for temporarily receiving a digital signal from the codec for receiving and compressing compressed data stored in the digital signal recording unit; A memory control unit controlling timing of writing and reading of the memory unit; An encoder for converting the digital signal read from the memory unit into an analog signal and receiving the sync signal into a composite video signal; And a video output unit configured to output the composite video signal converted by the encoder to a split screen or a single screen.

1 is a system block diagram showing an electrical configuration of a digital video signal recording / reproducing apparatus of the present invention.

*** Explanation of symbols for the main parts of the drawing ***

10. Buffer, 15. Multiplexer,

20, 45. Decoder 25. Memory section,

30. memory controller, 35. encoder,

40.OSD, 50.Codec,

55. Interface unit, 60. System control unit,

65. Hard disk

Hereinafter, a digital video signal recording / reproducing apparatus according to a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings.

1 is a system block diagram showing an electrical configuration of a digital video signal recording / reproducing apparatus of the present invention. In this embodiment, video signals are inputted from four video cameras. As shown in FIG. 1, the digital video signal recording / reproducing apparatus of the present invention includes a buffer 10 and a video camera which cyclically outputs video signals inputted from four video cameras (Video1, Video2, Video3, Video4). The multiplexer 15 sequentially converts the image signal input from the field or frame unit, and separates the horizontal and vertical sync signals from the analog image signal sequentially converted from the multiplexer 15, and the luminance (Y) and the color difference signal (BY, A decoder (20, 45) for converting the separated luminance and chrominance signals into digital signals after separation by RY), and the luminance signal and the chrominance signal or codec (50) separated from the decoder 20 for digital conversion. A memory unit 25 for receiving and temporarily storing the digital luminance and chrominance signals of the digital device, and a memory unit 30 and a memory unit 25 for controlling timing of writing and reading of the memory unit 25. Encoder 35 for converting a digital luminance and color difference signal into an analog signal, and converting the luminance and chrominance signal into a synthesized video signal by loading a synchronization signal received through the memory controller 30 into a converted image signal, and input of each video signal. The on-screen display unit 40 which synthesizes information about a channel and the like into a subtitle and displays the subtitle data by the OSD unit 40 and the on-screen display 40 A video output unit (MON) that outputs a split screen or a single screen on a screen, and a luminance signal and a color difference signal read by the decoder 45 are compressed or a luminance and color difference signal stored in the hard disk 65 is received and received. A codec (decoder / decoder; coder-decoder) 50, which is decompressed and output to the memory unit 25, receives a synchronization signal extracted by the decoder 45, and synchronizes a video signal to obtain a codec ( The interface unit 55, which delivers the data compressed by 50) to the system control unit 60, controls the entire system and converts the compressed data received from the interface unit 55 into a file format for preserving it as a file and converts it into a file format. A system control unit 60 for transferring the converted data to the hard disk 65 and a hard disk 65 for storing data in a file format entered through the system control unit 60 are provided.

Hereinafter, the operation process and the effect of the above-described digital video signal recording / reproducing apparatus will be described.

The video signals inputted from the four video cameras (Video1, Video2, Video3, Video4) sequentially converted through the buffer 10 and the multiplexer 15 are first separated from the horizontal and vertical sync signals by the decoder 20, and then the memory controller ( 30), and are separated into luminance Y and chrominance signals BY and RY. The separated luminance and chrominance signals are converted into digital signals and stored in the memory unit 25. At this time, the memory control unit 30 controls the timing for writing and reading the digital signal into the memory unit 25. The digital signal read out from the memory unit 25 is converted into an analog signal by the encoder 35 and receives the synchronization signal and the color burst signal inputted through the memory control unit 30 to convert the analog converted luminance signal and color difference signal into an image signal. Will be synthesized. The synthesized video signal converted by the encoder 35 is synthesized with the caption data by the OSD unit 40 and output to the monitor as a divided screen or a single screen.

In addition, the sync signal separated by the decoder 45 is input to the interface unit 55, and the digitally converted luminance and color difference signals are transmitted to the codec 50 and compressed. The data compressed by the codec 50 is converted into a file format for storage as a file by the system control unit 60 and stored in the hard disk 65.

When the data stored in the hard disk 65 is to be reproduced, the compressed data received from the codec 50 is decompressed and the decompressed digital format luminance and color difference signals are sent to the memory unit 25. The digital signal read out from the memory unit 25 is converted into an analog signal by the encoder 35 and receives a sync signal and a color burst signal input through the interface unit 55, and converts the converted luminance signal and color difference signal into an image signal. After synthesis, it is output to the monitor.

The digital video signal recording / reproducing apparatus of the present invention is not limited to the above-described embodiment, and can be implemented in various modifications within the range allowed by the technical idea of the present invention.

According to the digital video signal recording / reproducing apparatus of the present invention as described above, by converting the video signal input from one or more video cameras into a digital video signal and storing it in a hard disk, an image signal having excellent image quality can be provided. There is.

Claims (1)

The horizontal and vertical synchronizing signals are separated from the sequentially input image signals from the switching means for sequentially converting the image signals input from one or more video cameras in units of fields or frames, and the luminance and color difference signals are separated. A decoder for converting to a digital signal; A codec for compressing the digital signal read out from the decoder or extending the compressed digital signal; A digital signal recorder storing a digital signal compressed by the codec; A system controller which controls the whole system and converts the compressed data into a file format in order to preserve the digital signal compressed by the codec as a file in the digital signal recording unit; A memory unit for temporarily receiving a digital signal from the codec for receiving and compressing compressed data stored in the digital signal recording unit; A memory control unit controlling timing of writing and reading of the memory unit; An encoder for converting the digital signal read from the memory unit into an analog signal and receiving the sync signal into a composite video signal; And And a video output unit configured to output the composite video signal converted by the encoder to a split screen or a single screen.