KR100352295B1 - The system for realtime transfering multimedia data - Google Patents

Abstract

The present invention relates to a multimedia transmission system for providing multimedia information to a client through the Internet or a LAN network. More particularly, the present invention relates to MJ-code conversion of video data in hardware and to data transmission (or accommodation) of a client's access network (or system). By controlling and transmitting the video / audio synthesis rate according to the capability and providing the player optimized for the multimedia server, the video / audio synthesis rate control according to the data transmission amount providing the high quality multimedia information to the client in real time and the hardware MJ Peck A real-time multimedia transmission system using the transformation.

Description

Real-time multimedia transmission system using video / audio synthesis rate control based on data transmission amount and hardware M-JPEG conversion {The system for realtime transfering multimedia data}

The present invention relates to a real-time multimedia transmission system using video / audio synthesis rate control and hardware MJ conversion according to data transmission amount, and more particularly, to MJ code conversion of video data in hardware and to a client network (or system). By controlling the video / audio synthesis rate according to the data transmission capacity (or capacity) of the video), the video / audio synthesis rate control and the hardware MJ Peg conversion according to the data transmission amount to provide high quality multimedia information to the client in real time It relates to a real-time multimedia transmission system using.

Recently, as network (LAN) such as local area network (LAN) or wide area network (WAN) such as the Internet is widely spread and information transmission and data compression technologies are developed, information transmission such as video, audio, and graphics is simultaneously provided. Multimedia services are being promoted to improve the accuracy and variety of information and to satisfy the information through the five senses (currently visual and auditory).

Such multimedia services are utilized in various fields such as real-time Internet broadcasting service on the web or on-demand video service (V.O.D), video conferencing, and in-house broadcasting.

In addition, since the amount of multimedia data including video information is huge, the data volume is reduced and converted using various compression techniques for real-time monitoring or broadcasting on the web or network, and users can use the multimedia player to convert the data. The data is decoded and played back.

However, if the compression rate is increased to improve the transmission speed as described above, the video quality generally deteriorates, and thus the user has a limit in receiving a satisfactory multimedia service.

1 is a block diagram schematically showing a general configuration of a real-time multimedia transmission system.

As shown in FIG. 1, a live source capture means 1 such as a microphone or a camera obtains a live source that is performed in real time such as news, sports, performances, and the like through a wired or wireless communication network to a multimedia transmission server 2. Will be sent to. The multimedia transmission server 2 samples the obtained media analog signal at regular intervals, converts it into a digital signal, mixes video data and audio data at a predetermined rate, compresses the data using a specific codec conversion, and then The transmission is performed in real time to the client PCs 5 and 7 connected to the server 2 via the network 4 or the Internet 6 (WAN) 6.

In addition, the web server 3 is for providing a multimedia service on the web to a client connected through the Internet network 6, and designates the URL of the data in a web document (HTML, CGI, ASP, JAVA, etc.) When the client requests this web document, the data is transmitted through this URL, and the client plays the live source through a real or media player.

However, the conventional Internet broadcasting or real-time multimedia transmission system as described above generally compresses video data using MPEG codec, and MPEG compression enables high compression of 250: 1 or more, thereby increasing the amount of data transmitted. Although it can reduce and increase the transmission speed, it is not only asymmetric in decoding decoding, but also has a problem in that image quality is degraded during playback. In other words, MPEG format or RA / RM format which is generally used in video processing such as real system or media player increases loss of data in real-time transmission system because the higher the resolution, the greater the delay of transmission data. At the same time, the display screen is made very small for high quality.

In addition, when the multimedia transmission server 2 compresses data, the CPU performs floating code operation and performs codec processing in association with compression (MPEG, etc.) software. This can put a strain on the processing power, which can lead to a decrease in client connections and server downtime.

On the other hand, since the clients access the multimedia transmission server 1 through various network paths and their respective computer systems, the bandwidth or data capacity of the network is different for each client. In addition to the transmission, the network state (dedicated line, telephone line, congestion, etc.) is not adequately coped with, and clients do not receive efficient multimedia services for their communication systems.

Therefore, the conventional multimedia transmission system as described above does not transmit high-definition video and audio information in real time, and a delay time of 15 seconds or more occurs, and therefore, services such as horse racing, sports, and news provided on the Internet are important. However, there is a problem that the operation is possible during the delay time and the information becomes useless.

In addition, parking lots, bank surveillance cameras, security systems, etc. because the data is transmitted in an unclear picture quality for real-time high-speed transmission, it may not be able to accurately identify the identity of vehicles, criminals, and the like.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an object of the present invention is to construct a M-code encoding method using hardware, and to maintain high quality image information by using this, as well as in data conversion and transmission and data reproduction. By shortening the delay time as much as possible, it is to provide a real-time multimedia transmission system using a video / audio synthesis rate control and hardware MJ Peck conversion according to the data transmission amount to provide high-quality multimedia information to the client in real time.

1 is a block diagram schematically showing the configuration of a general multimedia transmission system.

Figure 2 is a block diagram showing the configuration of a real-time multimedia transmission system implemented on the web according to the present invention.

3 is a block diagram showing the configuration of a real-time multimedia transmission system through a plug-in player according to the present invention.

<Description of Symbols for Main Parts of Drawings>

1. Live source capture means 2,20. Multimedia transmission server

3,38. Web server 5, 7, 40. Client PC

21.Video Capture Cards 22,26. A / D converter

23. MJPEG Codec 24,28. PCI controller

25. Audio Capture Card 27. Audio Codec

30. Multimedia Processing Unit 33. Main Processor

34. Subprocessor 35. Video / Audio Synthesis

36. Transmission capacity checker 37. Client socket

43. Web Browser 50. Plug-in Player

51.Video/Audio Separator 53,55. Stream buffer

56. Media Playback

In order to achieve the above object, the real-time multimedia transmission system using the video / audio synthesis rate control and the hardware M-JPEG conversion according to the data transmission amount according to the present invention obtains the analog video signal and converts it to digital and M-JPEG codec. A video capture card for converting and transmitting to a multimedia processing apparatus; an audio capture card for receiving an analog voice signal and converting the digital codec and an audio codec to a multimedia processing apparatus and transmitting the converted audio codec; and an M-JPEG type received from the video capture card. Video buffers for temporarily storing video data, audio buffers for temporarily storing audio data received from the audio card, and a predetermined amount of data per hour transmitted to the client PC for each client socket to check the client's data capacity. Judging capacity check A multimedia processing apparatus having a video / audio mixing unit configured to adjust a mixing ratio of a video signal and an audio signal according to the checked data capacity of the client and transmit the same through a corresponding client socket; And a client PC for restoring the audio signal.

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

2 is a block diagram schematically illustrating a configuration of a multimedia transmission system implemented on a web according to the present invention.

As shown in FIG. 2, the present invention provides a multimedia transmission server 20 and a web hosting server including a web server 38 to which a client PC 40 is interconnected through a network such as an internet network. The live source is transmitted to the clients connected to the web server 38 through data conversion and compression in real time.

The multimedia transmission server 20 obtains an analog video signal from a camera or the like, and converts the digital capture and the MJ-code into a video capture card 21 for transmission to the multimedia processing device 30 and an analog voice from a microphone. The audio capture card 25 transmits the digital capture and the audio code conversion to the multimedia processing device 30 after receiving the signal, and transmits the obtained video and audio data by controlling the mixing ratio according to the bandwidth of the client network. And a web processing server 38 for transmitting multimedia data in a web transmission form to a client connected on the web.

The video capture card 21 receives an analog video signal from a camera or the like, samples at a predetermined period (or frames per second fps and sampling rate bitrate), converts it into a digital signal, and forms an original video file in RGB format. A D-converter 22 and an M-JPEG codec 23 for encoding the RGB data received by the A / D converter 22 according to the JPEG format and compressing the data at a specific compression ratio; And a PCI controller 24 for transmitting M-JPEG data to the multimedia processing device at high speed.

The audio capture card 25 samples an analog audio signal received from a microphone or the like at regular intervals, and then converts the digital audio data into a specific compression format. An audio codec 27 for compression and a PCI controller 28 for transmitting the compressed audio data to the multimedia processing device 30 at high speed may be provided. As the audio codec 27, an audio codec conversion such as MPEG Layer-3, Windows Media audio codec, Voxware, or the like may be used.

In the compression (encoder) of moving image data (RGB type data) having a large amount of data as described above, the M-JPEG code conversion process in the video capture card 21 is transferred to the M-JPEG codec 23 without passing through the CPU. Because it is done directly in hardware, the task of the processor 33, 34, such as the CPU of the multimedia processing device 30 is relatively small, and the performance of the client itself is much more stable, and many clients connect. Even if the speed is not reduced, it may not occur.

On the other hand, the multimedia processing device 30 is a video buffer 31 for temporarily storing video data in the form of M-JPEG received from the video capture card 21 and the audio data received from the audio capture card 25 A transmission capacity checker 36 which checks the audio buffer 32 to be temporarily stored, the amount of data per time transmitted to the client PC 40 for each client socket 37, and determines the data capacity of the client; And a video / audio mixing unit for adjusting the mixing ratio of the video signal and the audio signal according to the checked data capacity of the client and transmitting the same through the corresponding client socket 37.

The main processor 33 is performed by the server 20 through the UNIX O / S operating system such as Solaris, Linux, or PreBusdie, such as the conversion and transmission of data by the control of the capture card 21 and the audio card 25, and client connection. It is a processor to control the overall process.

The subprocessor 34 is a processor for generating a socket 37 of a client and processing a task for each client when the client accesses the server 20. The subprocessor 34 generates a socket for each client and a video / audio mix ratio. Controls processing such as adjustment and transmission data amount check.

On the other hand, the video / audio mixing unit 35 is to form a series of multimedia streams by mixing a predetermined amount of video frame data and audio frame data, calculates the amount of data transmitted for a certain time, a low-speed network network In case of transmitting to the low performance client PC, it reduces the network burden by reducing the composition ratio of video data, and increases the relative composition ratio of video data to audio when the network bandwidth is large. Allows you to watch high quality video. Therefore, the video / audio mixing unit 35 transmits data at an optimal mixing ratio with respect to the data capacity of the network or the client PC, so that the client can receive the best multimedia service in his environment. In addition, the data capacity of the network or the client is determined by checking the data transfer rate per predetermined time for each client socket 37.

In addition, the web server 38 connected to the multimedia transmission server 20 is provided with a plurality of web programs 39 to convert the multimedia data into a web format to a client PC 7 connected through the Internet network 6. Provided on the web.

On the other hand, the client accesses the web server 38 through a web browser 43, separates the multimedia stream data into video and audio, restores the video data through the MJ decoder decoder 41, and the audio encoder (codec). Through the audio decoder 42 having the same compression format as that of (27), the live audio signal is restored, so that the live source can be viewed on the web in real time with no buffering and no downloading.

However, in the process of converting the format into a Java applet or the like for processing on the web, a delay of transmission occurs and a player composed of the Java applet may not process all the multimedia streams transmitted from the web server 38. As described below, the client can install the plug-in player 50 in his computer PC so that the client can be directly transmitted to the multimedia transmission server 20.

On the other hand, Figure 3 is a block diagram showing the general configuration of a multimedia transmission system via a plug-in player according to the present invention.

As shown in FIG. 3, the client PCs 5 and 7 include a video / audio separator 51, an MJ decoder 52, an audio decoder 54, a stream buffer 53, 55, Including a plug-in player 50 consisting of a media player 56 can be directly connected to the multimedia transmission server.

The plug-in player 50 is configured to be optimally compatible with the multimedia server 20 to maximize the performance of the server. When the client executes the player 50, the server 20 automatically operates. Access to the server and network capabilities to the limit of performance.

In addition, the present invention may be provided with a stream buffer (53, 55) of a predetermined capacity in order to prevent abnormal display phenomenon that may occur due to communication networks or other failures.

On the other hand, the stream buffer 53 for the video data may be made of a FiFo buffer, which temporarily stores the decoded video data (about 0.5 to 2 seconds) and then displays it through the media player 56, thereby providing a network. This function prevents screen disconnection due to anxiety.

The stream buffer 55 for the audio data may be formed as a circular buffer, which stores the decoded audio data to continuously reproduce the stored audio data when the multimedia stream is disconnected due to network instability, thereby overcoming the disconnection phenomenon. .

The present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the scope of the technical idea of the present invention.

According to the present invention made as described above, by processing M-code conversion in hardware and determine the transmission capacity of the connected network to transmit the video / audio mixing ratio in an optimal state, thereby reducing the multimedia transmission time to the maximum This enables real time broadcasting and enables clients to enjoy high quality multimedia services.

Claims (5)

A video capture card which obtains an analog video signal and transmits it to a multimedia processing device after digital conversion and M-JPEG codec conversion; An audio capture card which receives an analog voice signal and converts the digital audio signal and the audio codec to a multimedia processing apparatus; Each client stores a video buffer for temporarily storing M-JPEG type video data received from the video capture card, an audio buffer for temporarily storing audio data received from the audio card, and a predetermined amount of data transmitted to a client PC. Transmission capacity checker that checks the data capacity of the client by checking the socket, and adjusts the mixing ratio of the video signal and the audio signal according to the checked data capacity of the client and transmits the video / audio through the corresponding client socket. A multimedia processing apparatus having a mixing unit; And a client PC configured to receive the multimedia stream and restore video and audio signals. The real-time multimedia transmission system using the video / audio synthesis rate control and the hardware M-JPEG conversion according to the data transmission amount. The video / audio synthesis rate according to the amount of data transmission according to claim 1, further comprising a web server for allowing a client to watch live sources on the web in real time with no buffering or no download through a web browser. Real-time multimedia transmission system using control and hardware M-JPEG transformation. The video capture card of claim 1, further comprising: an A / D converter for receiving an analog video signal from a camera or the like, sampling at regular intervals, and converting the same into a digital signal; and RGB data from the A / D converter. A real-time multimedia transmission system using video / audio synthesis rate control and hardware MJ conversion according to the data transmission amount, characterized in that it comprises the MJ codec that encodes and compresses according to the MJPEC format after receiving the. delete 2. The method of claim 1, wherein the client PC includes a plug-in player optimized for a multimedia transmission server, a FiFo scrim buffer for storing a predetermined amount of video data to be decoded, and a circular stream buffer for storing a predetermined amount of audio data to be decoded. Real-time multimedia transmission system using video / audio synthesis rate control and hardware M-JPEG conversion according to the data transmission amount.