KR0171756B1 - Method and apparatus for extracting the standing fictures from a receiver of digital dbs - Google Patents

Abstract

The present invention provides a digital DBS capable of extracting a desired still picture during viewing of a video program by outputting a decoded video signal output from the decoding means and stored in the buffer to a recording medium by the buffer output signal selecting means. An apparatus for extracting a still image of a receiver and a method of extracting the same, the method comprising: decoding a VES signal for a received image signal from a DBS receiver 8 through an MPEG2 system demux 16, and a corresponding buffer of a storage means 24; Video coding means 18 for outputting a video signal to a point; selection from the storage means 24 and command commander 30, in which the video signal from the video decoding means 18 is stored in the buffer portion of the point. And a buffer output signal selection means 28 for outputting the video signal stored in the storage means 24 to the recording means 26 by a signal. .

Description

Method and apparatus for extracting the standing fictures from a receiver of digital DBS

1 is a block diagram of a still image extraction apparatus of a digital DBS receiver according to the present invention.

2 is a view schematically showing a process of outputting a still image signal from a storage means to a recording means according to the present invention.

3 is a flowchart showing the operation flow of the still image extraction apparatus and the extraction method of the digital DBS receiver according to the present invention.

* Explanation of symbols for main parts of the drawings

8: Digital DBS (Direct Broadcastign Stellite) Receiver

10: tuner portion 12: channel decoder portion

14 Descrambler 16 MPEG2 System Demux

18: video decoder unit 20: audio decoder unit

21: video output unit 22: decoder unit

23: speaker 24: DRAM

26: recording means 28: microprocessor

30: Command Authorization 32: Modem

34: smart card 36: subscriber station management system

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to recording a predetermined still picture of an image received through a digital DBS receiver to an external digital storage medium, and in particular, a decoded video signal output from decoding means and stored in a buffer unit. And a method for extracting a still image of a digital DBS receiver, which outputs a predetermined image signal to a recording medium by a buffer output signal selection means, so that a desired still image can be extracted during viewing of a video program.

Conventional digital still images require considerable storage capacity and bandwidth during storage and transmission due to the large amount of representation information, and image compression technology is essential to effectively store and transmit them without distortion.

This has resulted in many international standardizations such as Joint Bi-level Image Experts Group (JBIG), Joint Photographic Experts Groups (JPEG), Moving Picturts Experts Group (MPEG), and H.261.

Here, JBIG is a standardized work for black-and-white still images, and standardization is mainly carried out around ISO / IEC / JTC1 / SC29 / WG29. JPEG stands for International Standardization for Standardization for Compression / Restoration of Still Images by the International Organization for Standardization (ISO).

H.261, on the other hand, is the standardization of the ITU-T processing in multiples of 65Kbps, which is the basic transmission speed of ISDN, for video data transmission.

In addition, MPEG is a standardization activity for moving picture encoding performed by ISO / IEC. MPEG-1 targeting a 1.5 Mbps general digital storage medium, CD-ROM with a 3 to 15 Mbps CD, ROM, Digital VTR, LDP, CATV, There are MPEG-2 for HDTV, and MPEG-4 of tens of Kbps for public telephone networks, video phones, and videotex.

The video compression algorithm of MPEG compensates for motion in units of blocks to reduce redundancy in time, and uses a compression algorithm based on discrete cosine code (DCT) to reduce spatial redundancy.

In other words, the image is divided into an intra (I) picture, a prediction (P) picture, and an interpolation (B) picture to reduce the bit rate due to interpolation and random access of the stored video for temporal redundancy reduction. By providing the access point for the book, the P picture is loaded by referring to the previous picture, and the B picture is formed by referring to the previous picture and the future picture, thereby increasing the compression ratio.

In addition, in order to remove redundancy in space, variable coding (VLC) and vector quantization technique (VQ) are used in combination with discrete cosine coding (DCT).

The bitstream of an MPEG video has six layers such as a block, a macroblock, a slice, a picture, a group of picture, and a sequence. In order to transmit such a bit stream through a communication channel, it is transmitted in packet units.

In addition, it is required to be standardized in order to use it in different applications. Moving Pictures Expert Group (MPG), a working group under the International Organization for Standardization (ISO), an international standardization organization, has been involved in video and audio since 1988. Development of relevant standards has begun.

Here, the proposed MEPG standard proposes MEPG-video, which defines a video signal compression algorithm, MEPG-audio, which specifies a compression algorithm for digital audio signals, and MEPG, which specifies the combination of encoded audio and video streams into one data stream. The system consists of three parts.

On the other hand, according to the data rate of the application codec is generally divided into MEPG1 and MEPG2, MEPG1 standardizes an algorithm capable of compressing video and related audio to about 1.5Mbps, these encoded audio and video streams into a single data stream It is prescribed to combine.

The specification has many applications in many digital storage media and communication channels, but is already in use in industrial and consumer electronics, particularly with CD-ROMs, which have high storage capacity and low cost.

In addition, MEPG2 standardizes an algorithm that can compress video and related audio signals to about 1.5Mbps. MEPG2-video uses block-based motion estimation and compensation to reduce temporal redunacy, and spatial redundancy. To reduce the spatial redunancy, a discrete cosine transform (DCT) compression method is used.

In addition, statistical redundancy is eliminated by using epitaxial coding such as two-dimensional Huffman coding, and visual redundancy is removed by adaptive quantization, which defines a compression algorithm that is optimized at about 1.5Mbps. Doing.

Accordingly, the present invention has been made to solve the above-mentioned problem, and by outputting a lyric video signal to a recording medium by a buffer output signal selection means, the decoded video signal output from the decoding means and stored in the buffer unit is desired. It is an object of the present invention to provide a still image extraction apparatus and a method of extracting a digital DBS receiver capable of extracting a video image.

The present invention provides a video decoding means for decoding the VES signal for the received video signal from the DBS receiver through MEPG2 system demux and outputting the video signal to the corresponding buffer point of the storage means; And a storage means for storing the video signal from the video decoding means into the buffer unit at the corresponding point, and a buffer output signal selecting means for outputting the video signal stored in the storage means to the recording means by a selection time from the command application unit. Characterized in that configured.

In addition, the storage means is characterized by consisting of the ES buffer unit, the OSD buffer unit, the first angle cover portion, the second angle cover portion, and the B frame buffer.

Decoding the VES signal for the received video signal from the DBS receiver through the MPEG2 system demux, and outputting the video signal to a corresponding buffer point of the storage means; Storing a video signal from the video decoding means into a buffer unit of a corresponding point; And outputting the video signal stored in the storage means to the recording means by the selection signal from the command application unit.

According to the present invention configured as described above, the decoded video signal output from the video decoder unit and stored in the storage means is recorded on the recording medium by outputting the still image signal to the recording medium by a buffer output signal selecting means.

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

1 is a block diagram of an apparatus for extracting a still image of a digital DBS receiver and a method of extracting the same according to the present invention, wherein the apparatus receives from a digital DBS (Direct Broadcasting Satellite) receiver 8 through an MPEG2 system demux 16. Video decoding means (18) for decoding the VES (Viedo Elementary stream) signal for the video signal and outputting the video signal to the corresponding buffer point of the storage means 24, and the video from the video decoding means 18. A buffer output signal for outputting a video signal stored in the storage means 24 to the recording means 26 by means of a storage means 24 in which a signal is stored in the buffer portion of the corresponding point and a selection signal from the command application unit 30; It comprises a selecting means 28.

In addition, the storage means 24 is composed of an ES (Elementary stream) buffer unit, the OSD buffer unit, the first anchor cover portion, the second anchor cover portion, and the B frame buffer portion.

In addition, the still image extraction method of the digital DBS receiver decodes the VES signal for the received image signal from the DBS receiver 8 through the MPEG2 system demux 16, and decodes the image to the corresponding buffer point of the storage means 24. Outputting a signal; Storing the video signal from the video decoding means (18) into a buffer unit of the corresponding point; And outputting the video signal stored in the storage means 24 to the recording means 26 by the selection signal from the command application unit 30.

On the other hand, when a predetermined still image of the screen is to be recorded while watching a video program, if a video signal is received through the DBS receiver 8, the video signal is not shown in the BS converter of the DBS receiver 8 (not shown). ) Is input to the tuner unit 910, and then the video signal from the tuner unit 10 is input to the MPEG2 system demux 16 through the channel decoder unit 12.

In this case, if the video signal input from the tuner unit 10 is a scrambled video signal, the video signal is the MEPG2 system demux 16 through the descrambler 14 by the control signal of the microprocessor 28. Will be entered.

Subsequently, the VES signal output from the MPEG2 system demux 16 is decoded by the video decoder 18 and output to the image output unit, and an image signal of one frame unit is output to the corresponding buffer point of the DRAM 24. In addition, the AES (Audio Elementary Stream) signal output from the MPEG2 system demux 16 is decoded by the audio decoder 20 and output to the speaker 23.

At this time, when the still image signal stored in the DRAM 24 is to be recorded, when the screen capture key 30 of the front side of the remote controller (not shown) is pressed, the screen capture signal is input to the microprocessor 28, The microprocessor 28 outputs an image capture control signal to the decoding unit 22 by the screen capture signal so that a still image signal of one frame stored in the DRAM 24 is output to the video decoder unit 18. do.

Thereafter, the still image signal of the one frame is recorded in the recording means 26 through the microprocessor 28.

2 is a diagram schematically showing a high-steady state in which a still image signal is output from a storage means to a recording means according to the present invention, wherein the video decoder 18 decodes and stores a still image signal of one frame for a predetermined screen. When outputted to the means 24, the storage means 24 outputs the video signal from the video decoder 22 to a buffer of the corresponding buffer point, for example, a first anchor cover, a second anchor cover, and a B frame. The buffer is stored in units of 1 frame.

Then, when the screen capture key 30 on the front of the remote controller (not shown) is pressed, the screen capture signal is input to the microprocessor 28, and the microprocessor 28 controls image capture by the screen capture signal. By outputting the signal to the decoding unit 22, the still image signal of one frame stored in the storage means 24 is output to the video decoder unit 18.

Thereafter, the still image signal of the one frame is recorded in the recording means 26 through the microprocessor 28.

3 is a flowchart showing the operation flow of a still image extracting apparatus and a method of extracting the digital DBS receiver according to the present invention. In the case where a predetermined still image is to be recorded while watching an image program, the image output unit 21 When the video signal being output to the first buffer unit is input to the predetermined buffer unit among the first anchor cover unit, the second anchor cover unit, and the B frame buffer unit, the buffer pointer of the image for the predetermined screen is obtained (S1).

Then, when the screen capture key 30 on the front of the remote controller (not shown) is pressed, the screen capture signal is input to the microprocessor 28, and the microprocessor 28 controls image capture by the screen capture signal. By outputting the signal to the decoding unit 922, a still image signal of one frame stored in the buffer pointer of the long-term DRAM 24 is output to the video decoder unit 918 (S2).

Next, the one frame still image signal is recorded in the recording means 26 through the microprocessor 28 (S3).

Thereafter, when the video signal of the B frame for the still picture is transmitted to the recording means 26 (S4), the recording of the still picture is ended, and if the recording is not performed, the process of step S2 is performed. Will be performed.

On the other hand, the reference numerals written in the components of the claims of the present application to facilitate the understanding of the present invention, and are not written in the intention to limit the technical scope of the present invention to the embodiments shown in the drawings.

As described above, according to the present invention, the decoded video signal output from the decoding means and stored in the storage means is output by the buffer output signal selection means to the recording medium to extract a desired video screen during viewing of the video program. It becomes possible.

Claims (3)

A video decoding means 18 for decoding the VES signal for the received video signal from the DBS receiver 8 through the MPEG2 system demux 16 and outputting the video signal to a corresponding buffer point of the storage means 24; The video signal stored in the storage means 24 is recorded by the storage means 24 in which the video signal from the video decoding means 18 is stored in the buffer section of the corresponding point, and by the selection signal from the command application section 30. And a buffer output signal selecting means (28) for outputting to the means (26). The still image of the digital DBS receiver according to claim 1, wherein the storage means (24) comprises an ES buffer portion, an OSD buffer portion, a first angle cover portion, a second angle cover portion, and a B frame buffer portion. Extractor. Decoding the large VES signal to the received video signal from the DBS receiver 8 via the MPEG2 system demux 16, and outputting the video signal to a corresponding buffer point of the storage means 24; Storing the video signal from the video decoding means (18) into a buffer unit of the corresponding point; And outputting the video signal stored in the storage means (24) to the recording means (26) in the selection signal from the command application unit (30).