KR19990005645A - Device for implementing video conferencing service in STB - Google Patents

Abstract

The present invention can implement video conferencing and video telephony in an environment such as LAN (LOCAL AREA NETWORK) by adopting a PCI (PROCESS CONTROL INTERFACE) bus from a set top box (STB), and separates the compressed audio video signal that is input. The video codec 30 to be extracted, the audio codec 20 to compress the data or vice versa to restore the transmitted data, the NTSC decoder 28 to convert an analog video signal and output to a TV, and the TV. In the STB, which consists of an NTSC encoder 24 that transmits data to the PC, a converter 22, a PCI controller 16 that interfaces through a PCI bus, and glue logic 18 that interfaces, A device for implementing video conferencing services.

Description

Device for implementing video conferencing service in STB

The present invention relates to a STB (SET TOP BOX), in particular by employing a PCI (PROCESS CONTROL INTERFACE) bus network environment such as LAN (LOCAL AREA NETWORK), ISDN (INTEGRATED SERVICE DIGITAL NETWORK), PSDN (PACKET SWITCHED DATA NETWORK) The present invention relates to a video conferencing service implementation apparatus in a set top box (STB) capable of implementing video conferencing and video telephony.

As is well known, the era of multimedia that integrates media such as voice, video, and data is rapidly spreading, and information retrieval services such as electronic library, electronic art museum, and information delivery using text and pictures have already been generalized by the Internet. It is not too long for services such as broadcast services such as home shopping, home shopping, home banking, telemedicine, distance education, and video telephony in videoconferencing. I'm going.

Next-generation networks are expected to create new cultures and industries, and these expectations are moving toward building broadband at high speeds that are incomparable to conventional telephone networks.

However, the current network is individually configured in a proper manner for each media, and in order to provide a multimedia communication service, there is a problem in that different media characteristics must be satisfied for each media because each media communication is not integrated into one. .

SUMMARY OF THE INVENTION An object of the present invention is to solve the conventional problems as described above. The present invention provides a STB (SET) for satisfying their different communication characteristics by integrating respective media communications into one when constructing a high-speed broadband network. TOP BOX) to provide a video conferencing service implementation device.

In order to achieve the above object, a configuration of the present invention provides an apparatus for implementing a video conferencing service in a STB including a main board connected through a PCI bus and an ATM NIU that is made of 188BYTE packets and output to an MPEG board. A video codec that compresses data or extracts an audio video signal that is input through a network, and an audio that compresses data by using G.7xx, an audio compression algorithm, or restores data transmitted vice versa. An audio codec, an NTSC decoder that converts a digital video format input from the video codec into an analog video signal and outputs it to a TV, and receives a video signal from a CCD (CONFERENCE CALL DEVICE) camera or a camcorder. NTSC encoder to convert data into digital video format A converter including an ENCODER, a function of A / D conversion of the audio signal received from the microphone, and a function of D / A conversion of the signal received from the AUDIO CODEC to the outside through a speaker; And a PCI controller for interfacing the output of the video codec with an ATM NIU, an MPEG board, and a main board through a PCI bus without passing through a system processor and a system memory, and for interfacing the PCI controller to an audio codec. It is characterized by consisting of glue logic.

1 is a schematic block diagram illustrating an apparatus for implementing video conferencing service in a set top box (STB) of the present invention.

Explanation of symbols for main parts of the drawings

10: main board 12: ATM NIU

14: MPEG Board 16: PCI Controller

18: GLUE LOGIC 20: AUDIO CODEC

22: Converter 24: NTSC Decoder

28: NTSC encoder 30: VIDEO CODEC

Hereinafter, an exemplary embodiment of the videoconferencing service implementing apparatus according to the present invention will be described in detail with reference to the accompanying drawings.

As shown in FIG. 1, the main board 10 is connected to the MPEG board 14 through a PCI bus, and the ATM NIU 12 (ASYNCHRONOUS TRANSFER MODE NETWORK INTERFACE UNIT) is made into an 188BYTE packet through an ATM switch. The board 14 outputs a stream STREAM and the video codec 30 outputs a signal as a stream.

Here, in ATM NIU (ASYNCHRONOUS TRANSFER MODE NETWORK INTERFACE UNIT), the data synchronized with the output clock are separated by 188 BYTE's fixed length MPEG transmission packet. It is similar to the ATM method standardized in ITT-U for the purpose of carrying multiple programs, and each transport packet constitutes 188BATM.

The MPEG board 14 receives an MPEG stream signal from the ATM NIU 12, releases compressed data, and is connected to the PCI controller 16 and the main board 10 through the PCI bus.

In addition, the video codec 30 is algorithm H.261 (mainly used for communication media (except for MPEG 1, storage media), and assumes the signal of the current TV camera, CIF (COMMON INTERMEDIATE FORMAT): 342 ( H) * 248 (V) * 30 (F), which is a common intermediate format of NTSC (720 * 240 * 60) and PAL (720 * 288 * 50), divided into 16 * 16 square pixels and processed. (H) * 18 (H) = 396 macroblock units, similar to the MPEG-1 algorithm, and H.221 (multiple video and audio data to enable transmission over ISDN) Applies to). The video codec 30 receives the data of the digital video format (R, G, B or Y, U, V) from the NTSC encoder 24 using H.26x, which is an image compression algorithm for realizing video conference. After compressing the data, the audio codec 20 multiplexes the compressed data together and transmits the data to a system not shown, and then transmits it through a network. In order to realize the conference, data is reconstructed into digital video format using H.26x, which is a video compression algorithm, and input to NTSC encoder 24. That is, a video signal (H sync: 15.734k, V sync: 59.94, impedance: 750HM, video level: 1Vpp) is output to a CCD camera or camcorder.

H.261 is accepted for video compression algorithms applied to videoconferencing, G.71x for audio compression algorithms, and H.221 for video audio multiplexing algorithms.

The audio codec 20 receiving the quantized data from the A / D compresses the data using G.7xx, which is an audio compression algorithm, and then restores the transmitted data using the above algorithm. Here, G.7xx is G.711 which encodes PCM (PULSE CODE MODULATION pulse code modulation) pulse (0.3-3.4K) voice into 64Kbps (8k * 8 bit) signal, and ADPCM (ADAPTIVE DIFFERENTIAL PCM adaptive pulse) High-quality voice in G.721 that encodes telephone (0.3-3.4K) voice of code modulation method into 32 Kbps (8k * 4 bit) signal and SB (SUBBAND) -PCM (band division adaptive differential pulse code modulation method) (0.05-7k: Radio broadcast quality) G.721 and LD-CELL (LOW DELAY CODE EXITED LINEAR PREDICTION low delay code excitation linear prediction method) 32K ADPCM method used for teleconference by encoding voice into 64kbps signal It is G.728 which is applied to voice of mobile phone and mobile communication and satellite communication in a manner that realizes voice quality equal to or higher than.

NTSC decoder 28 has a resolution of (330) (H) * 350 (V), input / output impedance of 750HM, video input / output level of 1Vpp, horizontal and vertical synchronization of 15.734k and 59.94k, and CCIR (INTERNATIONAL). RADIO CONSULTATIVE COMMITTEE) The 601 level is in 4: 2: 2 or 4: 1: 1 YUV output format, which converts the digital video format suitable for the characteristics of the NTSC encoder 24 into an analog video signal for output to the TV.

NTSC encoder 24 has (330) (H) * 350 (V) resolution, input / output impedance is 750HM, video input / output level is 1Vpp, horizontal sync is 15.734k, vertical sync is 59.94k, CCIR 601 level Is in 4: 2: 2 or 4: 1: 1 YUV output format and inputs video signals (H sync: 15.734 k, V sync: 59.94, impedance: 750 HM, video level: 1 Vpp) from CCD cameras or camcorders. It converts into a digital video format suitable for the video codec 30 and transfers this data to the video codec 30.

The converter 22 includes a function of A / D conversion of a voice signal received from the microphone and a function of D / A conversion of the signal received from the audio codec 20 (AUDIO CODEC) to the outside through a speaker. have.

The PCI controller 16 delivers the output of the video codec 30 directly to the video memory via the PCI bus without passing through the system processor and system memory, or delivers the compressed audio video stream to the system memory, or from the system memory. The main board 10, which does not use the H.26x and G.7xx algorithms, and the ATM NIU 12 and the MPEG board 14 are interfaced to the codec 30.

Referring to the operation of the present invention configured as described above are as follows.

When the video signal input from the CCD camera is converted into a digital format by the NTSC encoder 24 and then transmitted to the video codec 30, the video codec 30 uses H.26x, which is an image compression algorithm for realizing a video conference. To compress the data.

In the converter 22, the analog signal is quantized and then converted to digital or vice versa, and then the data is compressed or restored by the audio codec 20 using G.7xx, which is an audio compression algorithm.

The data compressed or decompressed by the audio codec 20 is applied to the PCI controller 16 due to the interface function of the glue tissue 18.

In addition, the ATM NIU 12 arranges the packets input from the outside and transfers the packets to the MPEG board 14 as MPEG streams. The MPEG board 14 releases the compressed data, and then interfaces with the PCI controller 16 through the PCI bus. do.

As such, the data delivered by the glue logic 18 and the video codec 30 are delivered directly to the video memory by the PCI controller 16 or compressed audio without passing through a system processor and system memory (not shown). The stream is delivered to the system memory or from the system memory to the video codec 30.

The present invention provides a video conferencing service implementation apparatus in a STB (SET TOP BOX) configured as described above by using the PCI controller is connected to the packet input through the ATM switch and the video and audio information input through the CCD camera as appropriate In the multimedia era, the present invention not only satisfies communication characteristics for each media but also implements a high-speed broadband network.

Claims (6)

In the STB consisting of a main board connected through a PCI bus and an ATM NIU 12 which is made into a 188BYTE packet and outputs to the MPEG board 14, a video conferencing service implementing apparatus using the algorithm H.2.xx A video codec 30 for compressing or extracting an audio video signal input through a network, and an audio codec for receiving quantized data and compressing the data using an audio compression algorithm, G.7xx, or restoring the transmitted data. (20) (AUDIO CODEC) and the digital video format inputted from the video codec 30 are converted into analog video signals to receive a video signal from an NTSC decoder 28 and a CCD camera or camcorder into a TV. NTSC encoder 24 which converts the data into digital video format and transmits the data, and A / D converts the audio signal received from the microphone. A converter 22 including a function for D / A conversion of the signal received from the audio codec 20 to the outside through a speaker; and a system processor for outputting the output of the video codec 30; PCI controller 16 for interfacing with ATM NIU 12, MPEG board 14, and main board 10 via a PCI bus without passing through system memory, and PCI controller 16 and audio codec 20 ( An apparatus for implementing video conferencing services in an STB, comprising glue logic 18 for interfacing the AUDIO CODEC. The video codec (30) according to claim 1, wherein the video codec (30) is an image compression algorithm for realizing a video conference by receiving data of a digital video format (R, G, B or Y, U, V) from an NTSC encoder 24. After compressing the data using H.26x, multiplex the compressed data together in the audio codec 20, or separate and extract the compressed audio video signal transmitted through the network and restore the video data to the digital video format after NTSC encoder. And a video conferencing service implementation apparatus in the STB. 3. The apparatus of claim 2, wherein the algorithm used for the video codec is H.26x for video compression and H.22x for video audio multiplexing. The compression algorithm used in the audio codec 20 (AUDIO CODEC) according to claim 1, wherein G.7xx is a 64Kbps (8k *) voice of pulse (0.3-3.4K) of PCM (PULSE CODE MODULATION pulse code modulation). G.711, which encodes an 8-bit) signal, and G.721, which encodes a telephone (0.3-3.4K) voice of ADPCM (ADAPTIVE DIFFERENTIAL PCM Adaptive Pulse Code Modulation) into a signal of 32 Kbps (8k * 4 bits). G.721 and LD- used for teleconferencing by encoding high-quality audio (0.05-7K: radio broadcast quality) voice into 64Kbps signals in SB (SUBBAND) -PCM (Bandwise Division-Differential Pulse Coded Modulation). CELL (LOW DELAY CODE EXITED LINEAR PREDICTION, Low Delay Coded Excitation Linear Prediction Type) It is G.728 which is applied to video and voice communication of mobile phone and satellite communication. Device for implementing video conferencing service in the STB. The NTSC encoder 24 has a resolution of 330 (H) * 350 (V), an input / output impedance of 750HM, a video input / output level of 1Vpp, horizontal synchronization of 15.734k, and vertical synchronization of 59.94k. And CCIR 601 level is 4: 2: 2 or 4: 1: 1 YUV output format. The NTSC decoder 28 has a resolution of 330 (H) * 350 (V), an input / output impedance of 750HM, a video input / output level of 1Vpp, horizontal synchronization of 15.734k, and vertical synchronization of 59.94k. And CCIR 601 level is 4: 2: 2 or 4: 1: 1 YUV output format.