KR100224623B1 - Image data storage device - Google Patents

Abstract

The present invention relates to a video data storage device of a DVCR, and includes a microcomputer 40 for inputting a selection signal and a frame number for selecting an image to be stored, and according to the selection signal and the frame number input from the microcomputer 40. And an external memory controller 50 for selectively outputting normal play data, and an external memory 60 for storing normal play data inputted from the external memory controller 50, the video cassette recorder tape being used in a video cassette recorder tape. As the reproduced image data is stored in the external memory 60 according to a user's selection, the necessary image may be edited or used by using a separate device.

Description

Image Data Storage {IMAGE DATA STORAGE DEVICE}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a digital video cassette recorder (hereinafter referred to as DVCR), and more particularly, to image data stored in a video cassette recorder tape (VCR tape), such as a memory IC card or a diskette. The present invention relates to an image data storage device that can be stored in an external memory such as a diskette) to edit or use an image required by another device.

Modern society is also called an information society, and as the amount of information to be processed is increasing day by day, data must be compressed to effectively use the existing transmission band.

In particular, in the case of digital video signals, since the amount of information is very large, it is necessary to compress the video data in order to more efficiently store, retrieve, and transmit the information.

For this reason, many compression techniques for image data have been developed. In summary, the compression of image data is reduced in order to reduce the amount of data required to display an image by removing spatial, temporal redundancy, and statistical redundancy.

The image data compression method can be classified into loss coding and lossless coding according to whether information is lost or not, and intraframe coding and temporal redundancy present in a video to remove spatial redundancy existed in still images. It can be divided into interframe encoding to remove.

Intra-frame encoding for removing spatial redundancy includes discrete cosine transform coding (DCT) and quantization, which are a type of transform encoding, and an example of inter-frame encoding for removing the temporal redundancy is two temporally adjacent screens. Motion estimation / compensation coding, which removes temporal heavyness by estimating and compensating motion of the liver.

In addition, by performing entropy coding on coefficient values that have undergone the discrete cosine coding (DCT) and quantization, statistical redundancy is removed.

That is, the entropy coding refers to a lossless coding algorithm for minimizing the bit rate by using a statistical property that a frequency of occurrence of quantized pixels is distributed differently and their entropy is smaller than B, and a code smaller than Bbpp exists. .

Such entropy coding techniques include Variable Lengh Coding (VLC), Run Length Coding (RLC), and Bit Plane Coding (BPC). Line length coding and variable length coding are the most widely used.

The length coding is mainly used to increase the compression efficiency of transform coding such as Discrete Cosine Coding (DCT). The transformed DCT coefficients are generally concentrated at low energy and high frequency components are almost zero. As they get closer to each other, a zig-zag scan is used to produce as long a zero-dimensional data stream as possible, followed by a two-dimensional symbol consisting of the number of consecutive zeros and non-zero coefficients that are immediately contiguous. .

In addition, the variable length coding is a technique of minimizing the bit generation rate by allocating small bits to symbols that are frequently generated according to the probability distribution of the symbols to be encoded, and assigning many bits to symbols having low occurrence.

There are many kinds of such variable length coding, but Huffman coding that is easy to implement is most widely used.

System coding is a technique for formatting the compressed video data bit stream to be suitable for transmission or storage in the above manner.

As the MPEG2 system international standard stipulates syntax and semantic rules, which are formatting rules as described above, when performing system encoding in a system encoder, a transport layer bitstream must be created according to the above rules. A system decoder must be designed to decode a transport layer bit stream made according to this rule.

As shown in FIG. 1, the DVCR encoder for storing the above-described transport layer bit stream in a recording medium such as a tape includes a clock generator 1, a timing signal generator 2, and a time stamp adder 3. Time Stamp Adder, first buffer 4, first buffer control 5, trick data extractor 6, first buffer 7, second buffer control 8, multiplexer (9), an error correction encoder 10, a modulator 11, and a recording device 12 are configured.

The clock generator 1 performs a phase locked loop (PLL) by using the clock encoding the input transport layer bit stream as a reference clock to generate a 27 MHz clock synchronized with the clock encoding the transport layer bit stream. The generated clock is input to the timing signal generator 2.

The timing signal generator 2 counts the clock input from the clock generator 1 and outputs a timing signal for displaying one track or an error correction coding block of a video cassette recorder tape. Output

The time stamp adder 3 uses the timing signal input from the timing generator 2 as the packet arrival time of the input transport layer bit stream to output the input transport layer bit stream in the same unit of time. A time stamp is added to each packet and input to the first buffer 4.

The first buffer 4 stores normal play data input through the time stamp adding unit 3, and the first buffer controller 5 stores data for low image play stored in the first buffer 4. Is read and output to the multiplexer (9).

The trick data extractor 6 extracts trick play data from the input transport layer bitstream and inputs the trick play data into the second buffer 7.

The second buffer 7 stores trick play data input from the trick data detector 6, and the second buffer controller 8 reads trick play data stored in the second buffer 7. And output to the multiplexer (9).

The multiplexer 9 multiplexes the data inputted from the respective buffer control units 5 and 8 to the error correction encoder 10, and the error correction encoder 10 receives the multiplexer 9. The data corrected through the error correction encoding is input to the modulator 11, and the error correction encoded data is modulated by the modulator 11 and then recorded on the tape through the recording device 12.

On the other hand, the DVCR decoder for reproducing the video data recorded on the tape as described above, as shown in Figure 2, the demodulator 21, the error correction decoder 22, the demultiplexer 23, the third buffer 24 And a third buffer control unit 25, a fourth buffer 26, a clock generator 27, a timing signal generator 28, and a timing controller 29.

In the DVCR decoder configured as described above, the demodulator 21 demodulates the video signal reproduced from the video cassette recorder tape through the playback device 20, inputs it to the error correction decoder 22, and the error correction decoder 22 ) Performs error correction decoding on the image data input from the demodulator 21 and inputs it to the demultiplexer 23.

The demultiplexer 23 separates the data input from the error correction decoder 22 into trick play data and normal play data, respectively, and inputs the data into the third buffer 24 and the fourth buffer 26, respectively.

The third buffer 24 stores the trick play data, and the third buffer controller 25 reads and outputs trick play data stored in the third buffer 24.

The clock generator 27 generates a 27 MHz clock and inputs the clock signal to the timing signal generator 28, and the timing signal generator 28 counts the clock input from the clock generator 27 to time the timing. The signal is input to the timing controller 29.

The timing controller 29 compares the timing signal input from the timing signal generator 28 with the time stamp added to the data packet for normal play input through the fourth buffer 26 to perform normal play at the same time. Outputs data for

However, the conventional DVCR decoder as described above has a problem in that necessary video cannot be edited or used by using image data stored in a tape.

Accordingly, the present invention is to solve the above-mentioned conventional problems, and more particularly, the image of the DVCR to store the image data stored in the video cassette recorder tape in the external memory to edit or use the required image with another device The purpose is to provide a data storage device.

1 is a schematic block diagram of a typical digital video cassette recorder (DVCR) encoder;

2 is a schematic block diagram of a general digital video cassette recorder (DVCR) decoder;

3 is a schematic block diagram of a digital video cassette recorder (DVCR) decoder equipped with a video data storage device according to the present invention;

FIG. 4 is a detailed block diagram of the external memory controller shown in FIG. 3.

Explanation of symbols for the main parts of the drawings

20: playback apparatus 21: demodulator

22: error correction decoder 23: demultiplexer

24: buffer 25: buffer control unit

26: buffer 27: clock generator

28: timing signal generator 29: timing controller

30: input key 40: micom

50: external memory control unit 51: transport stream demultiplexer

52: sequence header detector 53: buffer

54: buffer control unit 55: picture header detection unit

60: external memory

The video data storage device of the DVCR according to the present invention for achieving the above object,

A DVCR decoder for demodulating and error correcting and decoding video data reproduced on a video cassette recorder (DVCR) tape, and then separating the data data into normal play data and trick play data and storing them in an external memory, respectively.

A microcomputer for inputting a selection signal and the number of frames for selecting an image to be stored;

When storing the normal play data in the external memory according to the selection signal and the number of frames input from the micom, if the number of frames input from the micom exceeds the capacity of the external memory, only the number of frames that can be stored in the external memory is exceeded. And an external memory controller for controlling to store the data in the external memory.

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

4 is a schematic block diagram of a DVCR decoder with a video data storage device according to the present invention. The DVCR decoder with a video data storage device according to the present invention includes a demodulator 21, an error correction decoder 22, Demultiplexer 23, third buffer 24, third buffer controller 25, fourth buffer 26, clock generator 27, timing signal generator 28, timing controller 29, input The key 30, the microcomputer 40, the external memory control part 50, and the external memory 60 are comprised.

In the DVCR decoder configured as described above, the demodulator 21 is configured to demodulate the video signal reproduced from the video cassette recorder tape through the playback device 20 and input it to the error correction decoder 22. Reference numeral 22 denotes error correction and decoding of the image data input from the demodulator 21 and inputs it to the demultiplexer 23.

The demultiplexer 23 separates the data input from the error correction decoder 22 into trick play data and normal play data, respectively, and inputs the data into the third buffer 24 and the fourth buffer 26, respectively. have.

The third buffer 24 stores the trick play data, and the third buffer controller 25 reads and outputs trick play data stored in the third buffer 24.

The clock generator 27 generates a 27 MHz clock and inputs the clock signal to the timing signal generator 28, and the timing signal generator 28 counts the clock input from the clock generator 27 to time the timing. The signal is input to the timing controller 29.

The timing controller 29 compares the timing signal input from the timing signal generator 28 with the time stamp added to the data packet for normal play input through the fourth buffer 26 to perform normal play at the same time. It is intended to output the data for use.

In addition, the input key 30 is configured to input the selection signal of the required image and the number of frames desired to be stored after the selected image to the microcomputer 40 according to a user's manipulation.

The microcomputer 40 inputs the selection signal and the number of frames input through the input key 30 to the external memory controller 50.

The external memory controller 50 selects and outputs the normal play data output from the demultiplexer 23 according to the selection signal input from the microcomputer 40 and the number of frames, while the number of selected frames is output from the external memory 60. If the capacity is exceeded, the normal play data corresponding to the capacity of the external memory 60 is selected and output.

The external memory 60 includes a memory IC card, a diskette, and the like, and stores normal play data input from the external memory controller 50.

As illustrated in FIG. 4, the external memory controller 50 includes a transport stream demultiplexer 51, a sequence header detector 52, a buffer 53, a buffer controller 54, and picture header detection. The part 55 is comprised.

In the external memory controller 50 configured as described above, the transport stream demultiplexer 51 receives a normal play data, which is a transport layer bit stream input from the demultiplexer 23, and extracts only an image bit stream. Input to the header detection unit 52 is made.

The sequence header detector 52 detects a sequence header of an image bit stream input from the transport stream demultiplexer 51, and if the selection signal input from the microcomputer 40 is input, the sequence bit after the selection signal is input. The stream is input to the buffer 53.

The buffer 53 is configured to store a sequence bit stream input from the sequence header detector 52, and the buffer controller 54 reads a bit stream stored in the buffer 53 to read a picture header detector ( 55).

The picture header detector 55 detects a picture header of a bit stream input through the buffer controller 55, selects and outputs the frames as many as the frames input from the microcomputer 40, and outputs the frames. Control signals such as address signals and write signals required for storage are generated and output to the external memory 60, and when the number of frames input from the microcomputer 40 exceeds the capacity of the external memory 60, the external memory 60 is output. Only as many frames as can be stored in the frame is selected and output to the external memory (60).

3 and 4 will be described in detail with respect to the operation and effects of the image data storage device of the DVCR according to the present invention configured as described above.

The demodulator 21 demodulates the video signal reproduced from the video cassette recorder tape through the playback device 20 and inputs it to the error correction decoder 22, and the error correction decoder 22 is input from the demodulator 21. The corrected video data are subjected to error correction decoding and input to the demultiplexer 23.

The demultiplexer 23 separates the data input from the error correcting decoder 22 into trick play data and normal play data, respectively.

At this time, the normal play data output from the demultiplexer 23 is a bit stream composed of packets on the transport layer, and the bit stream is input to the external memory controller 50.

In addition, the external memory controller 50 selectively externally plays the normal play data input from the demultiplexer 23 according to the selection signal and the number of frames input by the user through the input key 30 and the microcomputer 40. It stores in the memory 60.

At this time, the data stored in the external memory 60 is an MPEG2 bit stream of an image layer.

In this case, the transport stream demultiplexer 51 of the external memory controller 50 extracts an image bit stream from the bit stream on the transport layer input from the demultiplexer 23 and inputs the image bit stream to the sequence header detector 52. The sequence header detector 52 detects a sequence header of an image bit stream input from the transport stream demultiplexer 51, and when the selection signal is input from the microcomputer 40, selects the sequence bit stream after the selection signal is input. It is stored in the buffer 53.

In addition, the buffer controller 54 reads the sequence bit stream stored in the buffer 53 and inputs it to the picture header detector 55, and the picture header detector 55 performs the sequence through the buffer controller 54. By receiving the bit stream, the picture header is detected by the number of frames inputted from the microcomputer 40, and the frames of the selected number of frames are stored in the external memory 60.

In this case, the picture header detector 55 generates a control signal such as an address signal and a write signal for storing the selected frame in the external memory 60 and inputs the control signal to the external memory 60.

When the number of frames input through the microcomputer 40 exceeds the capacity of the external memory 60, only the number of frames corresponding to the capacity of the external memory 60 is stored in the external memory 60.

As described above, according to the present invention, an image signal stored in a video cassette recorder tape may be stored in an external memory such as a memory device card or a diskette, thereby editing or using a necessary image using a separate device.

Claims (5)

A DVCR decoder for demodulating and error correcting and decoding video data reproduced on a video cassette recorder (DVCR) tape, and then separating the data data into normal play data and trick play data and storing them in an external memory, respectively. A microcomputer for inputting a selection signal and the number of frames for selecting an image to be stored; When storing the normal play data in the external memory according to the selection signal and the number of frames input from the micom, if the number of frames input from the micom exceeds the capacity of the external memory, only the number of frames that can be stored in the external memory is exceeded. And an external memory control unit for controlling the data to be stored in the external memory. The apparatus of claim 1, wherein the external memory is made of a memory element card. The image data storage device of claim 1, wherein the external memory comprises a diskette. The apparatus of claim 1, wherein the external memory controller comprises: a transport stream demultiplexer configured to receive normal play data and extract and output only a video bit stream; A sequence header detector for detecting a sequence header of an image bit stream input by the transport stream demultiplexer and selecting and outputting a sequence bit stream after a selection signal is input when a selection signal input by the microcomputer is input; A buffer for storing a sequence bit stream input from the sequence header detector; A buffer controller which reads and outputs a bit stream stored in the buffer; The buffer controller detects the picture header of the input bit stream, selects and outputs the frames as many as the frames input from the microcomputer, and generates control signals such as address signals and write signals necessary for storing the frames. And a picture header detector for inputting the memory into the memory. The DVCR as claimed in claim 4, wherein the picture header detector selects and inputs the frames to the external memory only as many as the frames that can be stored in the external memory when the number of frames input from the microcomputer exceeds the capacity of the external memory. Video data storage device.