TWI517688B - Method for controlling digital video device - Google Patents

Description

Method of controlling digital video device

The present invention relates to a method of controlling a digital video device, and more particularly to a method of controlling a digital video device to increase the speed of program switching.

With the rapid growth of multimedia technology, various video services have been released, such as terrestrial broadcasting, satellite broadcasting, cable broadcasting, and Internet TV, so that users can go home or go out. Enjoy high quality audio and video services. Therefore, as long as the user purchases a video and audio product that can receive the signal provided by the above service, such as a television, a set top box, etc., many interesting programs can be immediately seen.

However, when watching a TV program, the user must watch a program that is of interest to him, so the action of switching the program channel is inevitable. Please refer to FIG. 1. FIG. 1 is a functional block diagram of a general digital video device. The digital video device 100 includes a tuner 110, a demodulator 120, a demultiplexer 130, and a decoder 140. The tuner 110 is configured to receive a radio frequency signal S _RF having a plurality of transport streams (TS) and amplify and lock the received radio frequency signal S _RF to a specified frequency point to output a signal S _F . The designated frequency point is a corresponding frequency point of a program that the user wants to watch. The tuner 110 filters out signals of the above-mentioned multiple transmission streams that are not the designated frequency points. The demodulator 120 is configured to modulate the signal S _F output by the tuner 110 to a baseband signal to output a transport stream TS whose frequency is the specified frequency.

The demultiplexer 130 demultiplexes the transport stream TS to obtain Program Specific Information/Service Information PSI/SI and a process identifier PID. The program specific information/service information PSI/SI is basic information of DVB (Digital Video Broadcasting) for describing information such as a network, a transport stream, a program event, a service, and the like. The specifications followed by the program specific information/service information PSI/SI are formulated in the standard ISO/IEC 13818-1. In addition, the process identifier PID is used to distinguish information of different programs in the transport stream. The process identifiers corresponding to each program are different from each other.

The decoder 140 is configured to decode the program specific information/service information PSI/SI to output the video signal IMG. The video signal IMG can be transmitted to a display to display a corresponding picture.

Please refer to FIG. 1 and FIG. 2. FIG. 2 is a flowchart of controlling the digital video device 100 of FIG. 1 according to the prior art. According to the prior art method for controlling the digital video device 100, when the user controls the digital video device 100 to switch programs, the digital video device 100 first sets the frequency points of the tuner 110 and the demodulator 120 to cause the tuner 110 to And the frequency point of the demodulator 120 is adjusted from one frequency point to another frequency point (step S210). For convenience of explanation, in the following description, the frequency point to which the tuner 110 and the demodulator 120 are next locked is referred to as "designated frequency point". Thereafter, the digital video device 100 determines whether the tuner 110 and the demodulator 120 have been locked to the designated frequency point (step S220). If the tuner 110 and the demodulator 120 have not been locked to the designated frequency point, then step S220 is continued until the tuner 110 and the demodulator 120 are locked to the designated frequency point. Thereafter, the digital video device 100 turns on (enables) the demultiplexer 130 to cause the demultiplexer 130 to start demultiplexing the transport stream TS to obtain program specific information/service information PSI/SI (step S230). Thereafter, the digital video device 100 sets the decoder 140 to control the decoder 140 to start decoding the program specific information/service information PSI/SI to output the video signal IMG (step S240).

The above steps S230 and S240 must be executed after the steps S210 and S220 are completed. Therefore, according to the conventional control method, the demultiplexer 130 and the decoder 140 must wait until the tuner 110 and the demodulator 120 have locked to the designated frequency point, and then start the operations of demultiplexing and decoding, respectively. As a result, for some users who are pursuing performance, the digital video device 100 takes too long to perform program switching, and cannot meet its requirements.

The present invention provides a method of controlling a digital video device that can reduce the time required to switch programs, thereby increasing the speed of program switching.

The present invention provides a method of controlling a digital video device. The above method includes receiving a multiplexed transport stream through a tuner of a digital video device. The method further includes obtaining a process identifier corresponding to the designated frequency point, and setting a tuner and a demodulator of the digital video device to the designated frequency point. The method further includes turning on a demultiplexer of the digital video device to obtain program specific information/service information in the plurality of transport streams during the period in which the tuner and the demodulator are locked to the designated frequency point, and according to the process identifier. A decoder controlling the digital video device decodes program specific information/service information.

In an embodiment of the invention, the tuner is configured to filter out signals of the plurality of transmission streams that are not the designated frequency point, and the demodulator is configured to modulate the output signal of the tuner to the baseband signal to output the frequency. Specifies the transport stream for the frequency point.

In an embodiment of the invention, after the tuner and the demodulator are locked to the designated frequency point, the demultiplexer outputs program specific information/service information of the specified frequency point, and the decoder programs the specified frequency point. Specific information/service information is decoded.

In an embodiment of the invention, the decoder outputs a black screen picture signal before the tuner and demodulator are locked to the designated frequency point.

In an embodiment of the invention, after the tuner and the demodulator are locked, the decoder stops outputting the black screen picture signal, and outputs a video signal based on the result of decoding the program specific information/service information.

In an embodiment of the invention, the control digital video device is a set top box.

In an embodiment of the invention, the control digital video device is a digital television.

Based on the above, the present invention simultaneously turns on the demultiplexer of the digital video device while the tuner and the demodulator are locked to the designated frequency point, and controls the decoder to decode the program specific information/service information according to the process identifier. . Therefore, when the digital video device switches the program, since the operation of locking the frequency point and the operation of demultiplexing and decoding are performed at the same time, the switching time required for switching the program can be shortened, and the speed of program switching can be improved.

The above described features and advantages of the invention will be apparent from the following description.

Please refer to FIG. 3 and refer to FIG. 1 at the same time. 3 is a flow diagram of a method for controlling the digital video device 100 of FIG. 1 in accordance with an embodiment of the present invention. The main difference between the method of the present embodiment and the previous method is that the present invention turns on (enables) the demultiplexer 130 during the period when the tuner 110 and the demodulator 120 are locked to the designated frequency point. The program specific information/service information PSI/SI, and controls the decoder 140 to decode the program specific information/service information PSI/SI. In other words, when the tuner 110 and the demodulator 120 have not been locked to the designated frequency point, the demultiplexer 130 and the decoder 140 can be activated. Thus, the time required for the digital video device 100 to switch programs can be shortened, thereby increasing the speed at which the digital video device 100 switches programs.

According to the method of the embodiment, when the user controls the digital video device 100 to switch programs, the digital video device 100 first sets the frequency points of the tuner 110 and the demodulator 120 to make the tuner 110 and the demodulator 120 The frequency point is switched to the designated frequency point (step S310). The "designated frequency point" referred to herein is the same as defined in the above description, that is, the frequency point at which the tuner 110 and the demodulator 120 are next locked. Thereafter, the digital video device 100 simultaneously performs steps S320 and S330. In step S320, the digital video device 100 locks the tuner 110 and the demodulator 120 to a designated frequency point. In step S330, the digital video device 100 turns on the demultiplexer 130 to acquire program specific information/service information PSI/SI. After completing step S330, the digital video device 100 performs step S340 to control the decoder 140 to decode the program specific information/service information PSI/SI according to the process identifier PID corresponding to the designated frequency point to output the video signal IMG. Wherein, since steps S330 and S340 are performed in parallel with step S320, the manners of steps S210, S220, S230, and S240 are sequentially performed in comparison with the conventional process of FIG. 2, and the manner of the embodiment can reduce the time when the program is switched. And improve the speed of the program switching.

In an embodiment of the present invention, when the digital video device 100 is controlled to perform program switching, the digital video device 100 is controlled to obtain related information of a specified frequency point in advance, and the related information includes a process identifier PID corresponding to the designated frequency point. . Thus, when steps S330 and S340 are performed, the digital video device 100 can directly set the demultiplexer 130 and the decoder 140 without regard to whether the tuner 110 and the demodulator 120 have been locked to the designated frequency point. Further, before controlling the digital video device 100 to output the video signal IMG, the search operation is performed first, and the search operation is to scan the frequencies in the frequency list one by one according to the local standard frequency list. The control digital video device 100 parses the program information list from the radio frequency signal S _RF and stores the program list in a database. When the program is switched, the digital video device 100 is controlled to retrieve information (e.g., frequency, PID, etc.) of the program to be switched from the program list in the database, and to switch the program with the information.

In addition, before the tuner 110 and the demodulator 120 have not been locked to the designated frequency point, if the digital video device 100 has completed steps S330 and S340, the video signal IMG output by the decoder 140 will be a black screen picture signal, and if With an associated audio signal, the associated audio signal will be a mute signal. When the tuner 110 and the demodulator 120 complete the lock, the decoder 140 stops outputting the black screen picture signal, and outputs the video signal IMG based on the result of decoding the program specific information/service information PSI/SI.

In an embodiment of the invention, the control digital video device is a set-top box. In an embodiment of the invention, the above-described digital video control device is digital television.

Please refer to FIG. 4 and refer to FIG. 1 at the same time. 4 is a flow diagram of a method for controlling the digital video device 100 of FIG. 1 in accordance with an embodiment of the present invention. In step S410, the tuner 110 of the apparatus 100 receives a radio frequency signal S _RF multiplexed transport stream with the transmission of digital video. In step S420, the digital video device 100 acquires the process identifier PID corresponding to the designated frequency point, and sets the tuner 110 and the demodulator 120 of the digital video device 100 to the designated frequency point. In step S430, while the tuner 110 and the demodulator 120 are locked to the designated frequency point, the digital video device 100 turns on the demultiplexer 130 to obtain the program specific information/service information PSI/ in the above-described multiple transport stream. SI, and the program specific information/service information PSI/SI is decoded by the decoder 140 according to the process identifier PID.

In summary, the present invention simultaneously turns on the demultiplexer of the digital video device while the tuner and the demodulator are locked to the designated frequency point, and controls the decoder specific information/service information according to the process identifier. Decode. Therefore, when the digital video device switches programs, it is locked at the same time. The frequency action will be demultiplexed and decoded, so the switching time required to switch programs can be shortened, and the program switching speed can be improved.

Although the present invention has been disclosed in the above embodiments, it is not intended to limit the present invention, and any one of ordinary skill in the art can make some changes and refinements without departing from the spirit and scope of the present invention. The scope of the invention is defined by the scope of the appended claims.

100‧‧‧ digital video installation

110‧‧‧Tuner

120‧‧‧ demodulator

130‧‧‧Demultiplexer

140‧‧‧Decoder

S210~S240, S310~S340, S410~S430‧‧‧ Process steps

S _RF ‧‧‧RF signal

S _F . . . signal

TS. . . Transport stream

PSI/SI. . . Program specific information / business information

PID. . . Process identifier

IMG. . . Video signal

1 is a functional block diagram of a general digital video device.

2 is a flow chart for controlling the digital video device of FIG. 1 in accordance with the prior art.

3 is a flow diagram of a method for controlling the digital video device of FIG. 1 in accordance with an embodiment of the present invention.

4 is a flow diagram of a method for controlling the digital video device of FIG. 1 in accordance with an embodiment of the present invention.

S310～S340. . . Process step

Claims (7)

A method for controlling a digital video device, comprising: receiving, by a tuner of the digital video device, a radio frequency signal having a plurality of transport streams; obtaining a process identifier corresponding to a specified frequency point, and setting the digital video device a tuner and a demodulator to the designated frequency point; and during the tuner and the demodulator being locked to the designated frequency point, turning on a demultiplexer of the digital video device to obtain the multi-channel transmission Program specific information/service information in the stream, and a decoder of the digital video device is controlled to decode the program specific information/service information according to the process identifier. The method of claim 1, wherein the tuner is configured to filter out signals of the plurality of transmission streams that are not the designated frequency point, and the demodulator is configured to modulate the output signal of the tuner to the baseband signal. , the output stream is the transport stream of the specified frequency point. The method of claim 1, wherein when the tuner and the demodulator are locked to the designated frequency point, the demultiplexer outputs program specific information/service information of the specified frequency point, and the decoder The program specific information/service information of the specified frequency point is decoded. The method of claim 1, wherein the decoder outputs a black screen picture signal before the tuner and the demodulator are locked to the designated frequency point. The method of claim 4, wherein, after the tuner and the demodulator are locked, the decoder stops outputting a black screen picture signal and outputs based on a result of decoding the program specific information/service information. Video signal. The method of claim 1, wherein the digital video device is a set top box. The method of claim 1, wherein the digital video device is a digital television.