KR20020080048A - The video data coding method for the limited bandwidth channel application - Google Patents

Abstract

The present invention has been developed as a solution to simultaneously solve the problem of transmission speed and duplication, which is a problem of the existing video transmission, at the time of increasing the desire for multimedia communication with the development of a high-speed communication network.

The problem of multimedia communication in the high-speed communication network is the copyright problem in which the size of the media data that is large compared to the communication quality is copied.

In order to solve this problem, MPEG-1, 2, 3, 4, etc., which have reduced the data size, have been developed, and non-replicated stream transmission methods have been spread, but they are not satisfactory.

The communication quality guaranteed by home high-speed network varies from about 1Mbps to 8Mbps. This quality, however, falls far short of the speed that can be sent across multiple paths at the speed of the end user's network vendor's distributor.

In fact, according to the survey result of Benchbee site, it can be seen that it is staying at 300Kbps overseas, and the on-demand multimedia video service (VOD) which has to be serviced through various channels is not yet available for this reason.

In the present invention, in order to increase the quality of the communication speed by about 2 times, the method of separating the image data was developed, some of them were pre-stored on the user's computer, and some of them were designed to serve in real time. The problem of duplication was solved by making sure that the complete image is not stored without being stored and partly synthesized with real time data.

Through the present invention, it is possible to watch high-quality video at home, and also to solve a copyright problem, thereby implementing a new video on demand service (VOD).

Description

The video data coding method for the limited bandwidth channel application}

With the spread of high-speed communication networks, technologies for transmitting large amounts of data such as movies (eg movies) and playing them in real time on a PC have been developed. As a series of technologies, representative international standard technologies such as MPEG 1,2,3,4, which are data compression techniques to overcome the quality limitations of transmission lines, have been developed and applied to products. In particular, software such as Windows Media Player and Real Player occupy most of the world's market as application software that plays data transmitted by compressing with various compression technologies. However, even in the case of ADSL or cable modem, the average download quality does not exceed 300Kbps, so the quality of the playback video is very small or the resolution is much lower when playing in full screen mode. Falls. However, since DVD is available only through a separate DVD driver, users can obtain DVD titles directly, so they can't use VOD (VIDEO ON DEMAND) service that wants to transfer and watch videos from a remote server.

An object of the present invention is to provide a high quality video service similar to the DVD level on a current communication network (ADSL, cable) modem.

In order to protect the copyright of the video, the two challenges required for VOD service must be able to protect the transmitted video from being copied on the user's side, and overcome the technical barrier of compressing and restoring the transmission data to meet the transmission channel quality limit. It is. Therefore, the technical problem to be achieved by the present invention

-Compression technology that transmits DVD-level bulk data to 300Kbps transmission network

-Technology that makes it impossible to watch the data during playback even if the user cannot copy or duplicate the transmitted data

-Compression / playback technology for this.

.

In the present invention, in order to overcome the technical problem, the video data is divided into two parts, and one of them is downloaded in advance (non-real time) and the other part is transmitted in real time, and the data downloaded in advance and received in real time from the PC are received. We devised a way to combine and reproduce data.

The advantage of this method is that by dividing the video data in advance, it is impossible to play the video using only the non-real-time data downloaded by the user, so that it is possible to protect the content property rights such as the video and to allow the user to watch the high-capacity video playback within the narrow bandwidth. do.

The present invention consists of a video data segmentation method and video data coding and demodulation method for realizing such a design.

i) Video segmentation method

The video segmentation method for achieving the above object can be divided into two categories.

First: Screen Dividing Method

This method divides the screen for every frame of the image into N × N small screens as shown in Fig. 1, and randomly selects them in odd-numbered and even-numbered screens or in a specific order and re-edits them into two screens. This reduces the size of the split screen in half, using one of them for non-real-time downloads and the other for real-time downloads. Of course, at this time, the audio data is edited to be added for real-time download during division, thereby preventing audio reproduction during unauthorized reproduction of non-real-time downloaded data.

Second: how to divide the image pixel grade (grade level)

In the case of the color of the image data, RGB data is allocated to 8 bits each, and the information is represented by the color and intensity of each pixel.

As shown in FIG. 3, these video data can be divided into 8 bits each of the RGB into upper 4 bits and lower 4 bits.

In this case, the lower 4 bits better represent difference information between adjacent pixels, and the upper 4 bits have almost similar values in the background of similar colors. Therefore, when compressing these two separated image data, the higher 4 bit part has similar values between adjacent pixels, so more compression is possible. Therefore, in this case, if the video data of the upper 4bit part is used for real-time download, the non-real-time download data cannot identify the video at the user's random playback, so copyright protection is possible and high quality video playback is possible due to the limited quality of the transmission line. .

ii) Video data coding / playback method

4 is a block diagram of a device for transmitting and playing high quality video devised in the present invention.

The image segmentation module of the image segmentation compression apparatus can be used by selecting one of the two methods described above or a combination of the two. Coding and decoding of the divided image can use various coding methods developed in the past.

The segmented video playback apparatus is a playback software similar to the media player currently used and installed and operated in the user's PC.

By providing clear picture quality to consumers without BUFFERING phenomenon, it can provide true VOD service and can expand viewers such as broadcasting and education through internet so that there is no difference in time and space.

According to the quality of communication line, non real time and real time download data size can be selected and used to maximize the quality of communication line.

In addition, it is possible to prevent the copy or leakage of service material of the video.

Claims (4)

In order to overcome the limitations of channel bandwidth and to prevent video duplication and to provide VOD service, the video data is divided and pre-downloaded (caching) part of it in real time, and the rest is received in real time to play the original video. device In order to achieve the purpose of claim 1, a method of dividing a screen as shown in FIG. Method of dividing and transmitting the information (Grade Level) of the video pixel as shown in Figure 3 of the video data segmentation method to achieve the object of claim 1 High quality video playback system with the structure as shown in FIG. 4 for segmenting and playing video data