CN100401774C - Method for Realizing Large-Scale Digital TV Video on Demand on Unidirectional TV Network - Google Patents

Abstract

The invention provides a method for realizing large-scale digital TV video-on-demand on a one-way TV network. The method is that the front-end server sends the TV program to the TV network through digital broadcasting, and the user uses the TV set-top box to receive and select the digital broadcast of the corresponding TV program. The selected TV programs are cached on the hard disk in the set-top box for users to watch on demand; compared with the prior art, the method of the present invention overcomes the deficiencies in the prior art, and can support large-scale user demand without line modification. And it can provide enough programs for users to choose to order. Therefore, it has the characteristics of large storage capacity, random on-demand, and convenient use. The digital TV set-top box can be used externally or internally. For various types of TV sets that users already have, external ones can be used. TV manufacturers should Choose to produce a built-in TV to reduce the effective space occupied in the room.

Description

Method for Realizing Large-Scale Digital TV Video on Demand on Unidirectional TV Network

1. Technical field

The invention relates to a digital TV transmission and reception technology, in particular to a method for realizing large-scale digital TV video-on-demand on a one-way TV network.

2. Background technology

The main way to watch video programs now is to receive cable, wireless or satellite broadcasts through TV, which has the advantages of wide coverage and unlimited number of supported users, but it has its own weaknesses, such as fleeting, only passive order watch. Therefore, video on demand has attracted people's attention. Video on demand allows users to easily select programs and start playing from anywhere. At present, there are video-on-demand solutions based on various technologies:

Video-on-demand based on computer networks has been very mature after a long period of development, but due to the limitation of network bandwidth, the number of online video-on-demand users is limited. In order to increase the number of supported users, various latest and most advanced technologies are adopted, such as improving video compression rate, adopting server cluster and content distribution network. The comprehensive use of these technologies has increased the number of online video-on-demand users to a certain extent, but there is still a very large gap in the realization of universal services to home users.

On the basis of digital TV, the use of cable TV network to provide video-on-demand service has also been deeply researched, and two schemes have been proposed. The first is to transform the cable TV network into a two-way network, or use telephone dial-up or the Internet to transmit the user's on-demand and other control commands to the on-demand server, and the server controls the playback system to play the corresponding content and modulate it to the assigned channel. . In this way, each user has to monopolize a channel, and the number of users that can be supported is very limited, at most several hundred. The other is the quasi-video-on-demand method—NVOD. The video server delays and loops a TV program in several channels/channels, so that users can adjust the time to watch the corresponding program. The number of users supported by this method is not limited, but one program occupies multiple channels/channels, and there are very few programs to choose from.

Therefore, the current video-on-demand technology generally has the disadvantages of supporting few users or selecting on-demand programs, and there is still a long way to go to provide universal humanized services.

3. Contents of the invention

The purpose of the present invention is exactly to provide a kind of method that realizes digital TV video on demand on cable and terrestrial TV broadcasting network in order to overcome above-mentioned shortcoming, does not need to carry out line transformation, just can support large-scale user to carry out on demand, and can provide enough Programs for users to choose on demand.

The technical solution for realizing the object of the present invention comprises the following steps:

a. First, one or more analog channels are reserved in the frequency space of TV transmission as the program content transmission channel, and each reserved analog channel is called a pre-broadcast channel;

b. For a pre-broadcast channel, generate a digital transmission channel that exceeds the normal digital TV broadcast bandwidth, which can occupy the entire bandwidth of the analog channel at most. The front-end server reads the video program file and broadcasts data through this digital transmission channel. This process is called Preview the show. Different from ordinary TV, in order to make the program content reach the user end as soon as possible, the data broadcasting rate is higher than the program playback rate;

c. Before the program pre-broadcasting, formulate the program pre-broadcast sequence, and generate the pre-broadcast EPG for release;

d. The digital TV set-top box receives the pre-broadcast EPG, and displays the pre-broadcast program table for the user to select the program of interest;

e. The digital TV set-top box automatically receives the data broadcast in the pre-broadcast channel according to the pre-broadcast time of the selected program, and saves it in the hard disk for buffering for users to order. The digital TV set-top box monitors the available space of the hard disk, and when the space is insufficient, some programs are automatically deleted to accommodate new programs;

f. Once the program selected by the user starts to be received, the digital TV set-top box marks the program as an available program and prompts the user to play it.

The one pre-broadcast channel mentioned in step a generally occupies 8MHz frequency band.

Wherein, the bandwidth of the digital channel described in step b has some differences according to different modulation methods, for example, the transmission code rate of 64QAM used in cable TV can reach up to about 41.34Mb/s. On each pre-broadcast channel, when the broadcasting of all programs is completed, rebroadcasting is performed according to the broadcasting program list. In the case of multiple pre-broadcast channels, the pre-broadcast programs are broadcast in different places in different pre-broadcast channels. Taking three pre-broadcast channels as an example, for a set of well-prepared pre-broadcast programs ABCDEFGHIJ, the sequence of broadcasting on different channels according to time is shown in Figure 1. A pre-broadcast channel can release about 100 to 150 hours of DVD-quality video program content a day, which is equivalent to 60 to 90 standard movies.

Wherein the pre-broadcast EPG described in step c comprises the following contents: program name, program introduction, time length,

File size, <pre-broadcast channel number, start time, end time>, ..., <pre-broadcast channel number, start time, end time. A pre-broadcast plan for the next week or even a month can be made at a time, and hundreds or even thousands of movies can be provided according to the number of pre-broadcast channels. During the pre-broadcasting process, the list of pre-broadcast programs can be partially modified, programs added earlier can be removed, new programs can be added, and the EPG can be corrected accordingly.

Wherein the digital TV set-top box described in step d needs to have the EPG that supports this program pre-broadcast technology, can read and process the pre-broadcast program, and has a large-capacity hard disk. Digital TV set-top boxes are recommended to use dual tuners and have advanced power management functions.

In step d, displaying the list of pre-broadcasted programs to the user only needs to display content such as program introductions, and does not need to display the pre-broadcast time of the programs.

Wherein the data receiving of the pre-broadcast channel described in step e, for the double tuner digital TV set-top box, when the first tuner normally watches digital TV, the second tuner receives the prebroadcast content, avoids conflict, does not When watching TV, both tuners receive pre-broadcast content from different pre-broadcast channels; when the digital TV set-top box only has a single tuner, it can only receive it during the time when it is not watching TV. It is turned off when there is no need to receive the pre-broadcast. When the pre-broadcast program that needs to be received is reached, it will be automatically turned on in advance, and it will be turned off after receiving it. When it is working, it can turn off idle modules, such as hard disk, tuner, decoding chip, etc.

The hard disk used for buffering pre-broadcast programs mentioned in step e has a capacity of at least 60GB, and buffers 30 hours of DVD-quality programs, and recommends 160GB or more, and buffers 80 hours of programs. When the available hard disk space is not enough to accommodate the next pre-broadcast program to be received, the digital TV set-top box counts the information of the cached program, and automatically chooses to delete it according to the program file size, receiving time, whether it has been played, whether it is selected to be kept, etc. Part of the program to cache new pre-run programs.

Wherein in step f, the digital TV set-top box provides the user with a list of buffered and buffered programs for the user to enjoy on demand. Since the transmission rate of the pre-broadcast program is much higher than the playback rate, the user can enjoy it when receiving the pre-broadcast program.

Since the present invention adopts the method that users first define their own on-demand requirements, and then cache the content on the large-capacity hard disk of the digital TV set-top box, it can better cover the user's on-demand intentions, and the real on-demand is carried out locally without being affected by external factors such as the network. , with full control, works great.

4. Specific implementation

The technical solution for realizing the object of the present invention comprises the following steps:

a. Store a large number of video program files in the storage server of the front-end system of cable or wireless TV;

b. Select some programs in the front-end system as the pre-broadcast content for a certain period of time to form a pre-broadcast program list. In addition, during the pre-broadcast process, some programs selected earlier can be removed from the pre-broadcast program list at any time, and new ones can be added. program;

c. The front-end system generates a pre-broadcast EPG according to the pre-broadcast program list at any time, and broadcasts to the TV network. The pre-broadcast EPG includes the following contents: program name, program introduction, duration, file size, <pre-broadcast channel number, start time, end time>, ..., <pre-broadcast channel number, start time, end time>;

d. The digital TV set-top box that supports program pre-broadcast receives the pre-broadcast EPG, and provides the user with the name and introduction of the pre-broadcast program, and the user can choose a large number of interested pre-broadcast programs;

e. The digital TV set-top box receives from the corresponding pre-broadcast channel according to the pre-broadcast time of the pre-broadcast program selected by the user, and caches it on the large-capacity hard disk;

f. The digital TV set-top box prompts the user with a program list that has been or is being cached locally, and the user can order and enjoy it.

The digital TV set-top box can be external or built-in. For various types of TVs that users already have, external ones can be used, and TV manufacturers should choose to produce built-in TVs to reduce the effective space occupied in the room.

Claims (6)

1. The method for realizing large-scale digital TV video on demand on a one-way TV network is characterized in that the front-end server sends the TV program to the TV network through digital broadcasting, and the user uses a digital TV set-top box with a hard disk memory to receive and select the corresponding TV program. Broadcasting, the selected TV programs are cached on the hard disk in the digital TV set-top box for users to order and watch; the order method includes the following steps: a. Firstly, in the frequency space of TV transmission, one or more pre-broadcast channels are reserved as program content sending channels; b. Each pre-broadcast channel generates a digital transmission channel that exceeds the broadcast bandwidth of normal digital TV. The maximum bandwidth of this digital transmission channel is the entire bandwidth of the pre-broadcast channel. Program preview; c. Before the program pre-broadcasting, formulate the program pre-broadcast sequence table, and generate the pre-broadcast EPG for release; d. The digital TV set-top box receives the pre-broadcast EPG, and displays the pre-broadcast program list for the user to choose; e. According to the pre-broadcast time of the selected program, the digital TV set-top box automatically receives the data broadcast in the pre-broadcast channel and saves it in the hard disk for buffering, so that users can order it; f. Once the program selected by the user starts to be received, the digital TV set-top box marks the program as an available program and prompts the user to play it. 2. the method for realizing large-scale digital television video-on-demand on one-way TV network according to claim 1, is characterized in that, the broadcast rate of program content is higher than normal play rate during pre-broadcasting, so that program content can be broadcasted more quickly When reaching the user end, try to use the full bandwidth of the analog channel while maintaining the reliability of the transmission. 3. the method for realizing large-scale digital television video-on-demand on one-way television network according to claim 1, is characterized in that, pre-broadcast program sequence is arranged, broadcast on the pre-broadcast channel, in a plurality of pre-broadcast channels In some cases, the pre-broadcast programs are staggered and broadcast on different channels, and the channel and time arrangement of the pre-broadcast programs are released in the form of EPG. 4. the method for realizing large-scale digital TV video on demand on one-way TV network according to claim 1, is characterized in that, the digital TV set-top box searches for the pre-broadcast of program in the pre-broadcast EPG according to the list of pre-broadcast programs selected by the user channel and time. 5. the method for realizing large-scale digital television video-on-demand on one-way television network according to claim 1, is characterized in that, the digital set-top box that realizes large-scale digital television video-on-demand method on one-way television network adopts double tuner to receive One of the high-frequency heads is used to receive normal digital TV, and the other high-frequency head is used to receive program previews. When not watching TV, the two high-frequency heads receive program previews at the same time. 6. the method for realizing large-scale digital TV video on demand on the one-way TV network according to claim 5 is characterized in that, in the digital TV set-top box, a large-capacity hard disk is used to cache the pre-broadcast program content, and when the available space of the hard disk is not enough, the digital TV The set-top box automatically deletes part of the program content according to the storage time of the program or the number of times it is played.