KR100452614B1 - Method for trick play in digital broadcasting receiver - Google Patents

Abstract

The present invention relates to a trick play method in a digital broadcast receiver, and does not separately generate and record a search information file or the like for a broadcast program recorded on a hard disk (HDD) in a digital broadcast receiver such as a set-top box (STB), Instead, according to the user's request speed, the variable read speed of the broadcast program recorded on the hard disk is variably controlled, and I-picture data is selected from the read broadcast program data. By intermittently or repeatedly playing according to the playback speed requested from the user, various trick speeds can be performed, thereby preventing the file system of the hard disk from being complicated by the search information file. It is also possible to create, record and read the navigation information file. It is a very useful invention that allows the elimination of complex components and algorithms.

Description

Method for trick play in digital broadcasting receiver

The present invention provides a trick play in a digital broadcast receiver such as a set top box that receives a digital broadcast program, transmits it to an external connected device, and records and stores the same on a recording medium such as a hard disk (HDD). It is about a method.

In conventional analog television broadcasting, a video signal is transmitted through radio wave and wired cable by AM modulation or FM modulation, but recently, digital television broadcasting has been developed according to the development of digital technologies such as digital image compression and digital modulation / demodulation. Standardization and commercialization are rapidly progressing, and conventional terrestrial, satellite, and cable broadcasting are also being digitized based on the Moving Picture Experts Group (MPEG).

On the other hand, the digital broadcast as described above, according to the development of digital video / audio compression technology and digital transmission technology can provide a higher quality broadcast service than the analog broadcast signal service, in particular multiplexing and transmitting a plurality of broadcast programs in the same bandwidth And it has an advantage that can greatly increase the interoperability with digital communication media and digital storage media.

In the digital broadcast, a plurality of broadcast programs encoded on the basis of MPEG are multiplexed and transmitted in a transport stream, and the transport stream is a digital receiver such as a set-top box (STB) installed at a receiving side. A plurality of broadcast programs received by the broadcast receiver and included in the transport stream are demultiplexed.

Therefore, only one broadcast program desired by the user can be selected, and in a digital broadcast receiver such as the set-top box, the selected broadcast program is restored to the original audio and video signal by using a decoder provided in the receiver. After that, the output is transmitted to an A / V output device such as a general television.

Recently, a large capacity hard disk (HDD) is additionally provided in a digital broadcast receiver such as the set-top box, and a program recorded on the hard disk is stored and stored on the hard disk. According to the user's request, it is expected that a digital broadcast receiver having a digital broadcast recording / reproducing function for reproducing and outputting a broadcast program recorded on the hard disk will be developed and released.

In addition, a search information file including a plurality of navigation information for searching and reproducing and reproducing a broadcast program recorded on the hard disk HDD is generated, and a file system of the hard disk may be generated. Navigation information recorded in the search information file when additional play is recorded, and when a user requests trick play, for example, a trick play of various speeds such as high speed playback or low speed playback is requested. By using the, a trick for a corresponding trick play operation is being proposed from the relevant companies.

However, in order to generate a search information file including various navigation information for searching and reproducing a broadcast program recorded and stored on a hard disk (HDD) as described above, and to additionally record the search information file in the file system of the hard disk, the search information file In addition to the need for complex algorithms and configuration means for generating the data, the file system of the hard disk becomes complicated, and a complex playback algorithm for reading and utilizing the navigation information recorded in the search information file is necessary. Problems will arise.

Accordingly, the present invention was created to solve the above problems, and does not separately generate and record a search information file for a broadcast program recorded on a hard disk (HDD) in a digital broadcast receiver such as a set-top box (STB). Instead of controlling the data read speed of the broadcast program recorded and stored on the hard disk according to the user's requested speed, I-picture data is selected from the read program data. Accordingly, an object of the present invention is to provide a trick play method in a digital broadcast receiver for intermittent playback or repeat playback according to a playback speed requested by a user, so that trick play at various speeds can be performed.

1 illustrates a configuration of a digital broadcast receiver to which a trick play method according to the present invention is applied;

2 illustrates a detailed configuration of a stream decoder of a digital broadcast receiver according to the present invention.

3 is a table showing information included in MPEG-2 encoded data used in the trick play method according to the present invention;

4 is a flowchart illustrating a trick play method in the digital broadcast receiver according to the present invention.

※ Explanation of code for main part of drawing

10: Demultiplexer 11: Buffer Memory

12: hard disk 13: micom

14 memory 15 stream decoder

150 Parser 151 Video Decoder

152: Audio Decoder 153: Text Decoder

154: I-picture detector

A trick play method in a digital broadcast receiver according to the present invention for achieving the above object comprises the steps of: recording and storing digital broadcast program data on a recording medium; Shifting a data reading speed from the recording medium when a shift reproduction request for broadcast program data stored in the recording medium is requested; And selecting three pieces of the base image data of the variable speed read-out program data and intermittently or repeatedly restoring the output based on the requested reproduction speed.

Hereinafter, a preferred embodiment of a trick play method in a digital broadcast receiver according to the present invention will be described in detail with reference to the accompanying drawings.

First, FIG. 1 illustrates a configuration of a digital broadcast receiver to which a trick play method according to the present invention is applied. For example, a digital broadcast receiver such as a set-top box (STB) having a recording / playback function of a broadcast program is provided. The demultiplexer 10 may include a demultiplexer 10, a buffer memory 11, a hard disk 12, a microcomputer 13, a memory 14, and a stream decoder 15. The demultiplexer 10 may include a demultiplexer 10. In this case, a plurality of digital broadcast programs selectively output a transport stream (SPTS: Single Program TS) of any one program among the transport streams (MPTS: Multi-Program TS) of the multiplexed multi-program.

In the buffer memory 11, the transport stream selectively outputted through the demultiplexer is temporarily stored and then stored in the hard disk 12 at a predetermined write speed corresponding to the transmission speed of the broadcast program data. In addition to recording and storing, when the playback operation is performed, the microcomputer 13 controls broadcast program data recorded on the hard disk, for example, broadcast program data recorded as a transport stream or a PES stream (Packetized Elementary Stream). According to the signal, the data is read at a predetermined read speed and temporarily stored, and then output to the stream decoder 15.

The stream decoder 15 decodes the data stream of the broadcast program output from the buffer memory 11 and restores the original video and audio signals to the original video and audio signal. When the user requests a trick play operation at various double speeds such as high speed reproduction or low speed reproduction, the data read speed in the buffer memory 11 and the decoding operation in the stream decoder 15 are controlled, respectively. Allows trick play operations at various speeds to be performed. In addition, the memory 14 contains and records control data and information necessary for the control operation in the microcomputer 13.

Meanwhile, as illustrated in FIG. 2, the stream decoder 15 includes a parser for temporarily outputting the data stream after being temporarily stored in the buffer memory 11 as video, audio, text, and navigation information. Parser 150 and a video decoder 151, an audio decoder 152, and a text decoder 153 for decoding the separated output video, audio and text data and restoring and outputting the original video, audio and text data. It may be configured to include.

In addition, the stream decoder 15 may include an I-picture detector 154 for selectively searching for I-picture data with reference to navigation information separately output through the parser 150. In the I-picture detector 154, as shown in FIG. 3, information contained in MPEG-2 coded data, in particular, a picture start code (PSC: Picture) recorded in a picture layer of a video elementary stream Start Code (PC) information and Picture Coding Type (PCT) information are searched and checked, and output to the microcomputer 13 as search information for I-picture data.

Accordingly, when the user requests a trick play operation of various speeds such as high speed playback or low speed playback, the microcomputer 13 variably controls the data reading speed in the buffer memory 11, With reference to picture start code (PSC) information and picture coding type (PCT) information retrieved and output from the I-picture detector 154, only the I-picture data is selected by the video decoder 151, and intermittently played back, or A series of trick play operations for repeated playback are performed, which will be described in detail below.

4 is a flowchart illustrating a trick play method in the digital broadcast receiver according to the present invention. As described above, in the microcomputer 13, the buffer memory 11 is connected to the buffer memory 11 in response to a user's request for playback. By controlling the operation of the stream decoder 15, a general reproducing operation of reading and reproducing the broadcast program data recorded on the hard disk 12 at 1x speed is performed (S10).

Subsequently, when performing a trick play such as high speed playback from the user while performing the normal playback operation of 1x as described above (S11), the microcomputer 13 checks the playback speed of the high speed playback requested from the user. Thus, the data read speed in the buffer memory 11 is variably increased to 1x or more (S12). For example, when 4X playback is requested from the user, the data in the buffer memory 11 is increased. The reading speed is variably increased from 1x to 4x.

As described above with reference to FIG. 3, I-picture search information searched and output from the I-picture detector 154 included in the stream decoder 15, that is, navigation information included in MPEG-2 encoded data. Picture start code (PSC) information and picture coding type (PCT) information recorded in the picture layer of the video elementary stream are searched and checked, and the start position of the I-picture data is searched (S13).

Thereafter, the microcomputer 13 controls the video decoder 151 so that only the I-picture data is selected from the video data streams input to the video decoder, and restored to the original video data. For example, when the user requests a 4x playback operation, the video decoder 151 selects only I-picture data and controls the decoding operation to be performed intermittently, thereby performing a series of high speed playback tricks corresponding to the 4x playback operation. The play is made (S14).

In addition, the microcomputer 13 pauses the decoding operation of the audio decoder 152 and the text decoder 153 while performing the trick play of the high speed reproduction through the above-described process. This prevents unmatched audio or text from being displayed.

On the other hand, in the micom 13, when performing a trick play such as low speed playback from the user during the normal 1x playback operation (S20), by checking the playback speed of the low speed playback requested from the user, The data read rate in the buffer memory 11 is variably reduced to 1x or less (S21). For example, when 0.5x reproduction is requested from the user, the data read rate in the buffer memory 11 is reduced. Is reduced from 1 times to 0.5 times.

As described above, the I-picture search information searched and output from the I-picture detector 154 included in the stream decoder 15, that is, the video elementary stream of the navigation information included in the MPEG-2 coded data. Picture start code (PSC) information and picture coding type (PCT) information recorded in the picture layer are searched and checked, and a start position of the I-picture data is searched (S22).

Thereafter, the microcomputer 13 controls the video decoder 151 so that only the I-picture data is selected from the video data streams input to the video decoder, and restored to the original video data. For example, when a user requests a 0.5x playback operation, the video decoder 151 selects and decodes only I-picture data and repeatedly reproduces and outputs the same, thereby performing a series of operations corresponding to 0.5x playback. The trick play of the low speed reproduction is made (S23).

In addition, the microcomputer 13 pauses the decoding operations of the audio decoder 152 and the text decoder 153 while performing the trick play of the low speed reproduction through the above process, thereby reproducing the low speed. Audio or text that does not match the image may be prevented from being displayed.

The above-described preferred embodiments of the present invention are disclosed for purposes of illustration, and within the technical spirit and scope of the present invention disclosed in the appended claims, various other embodiments are improved, changed, replaced Or addition may be possible.

The trick play method in the digital broadcast receiver according to the present invention constructed and constructed as described above separately generates a search information file for a broadcast program recorded on a hard disk (HDD) in a digital broadcast receiver such as a set-top box (STB). Instead of recording, instead of controlling the data read speed of the broadcast program recorded and stored on the hard disk according to a user's requested speed, an I-picture of the read broadcast program data. By selecting data and intermittently or repeatedly playing the data according to the playback speed requested by the user, and performing trick play at various speeds, the file system of the hard disk is complicated by the search information file. It can be prevented at the source, and the search information file is generated. And it would be very useful to be able to delete the inventors complex configuration and algorithm means for using the read.

Claims (3)

Recording and storing the digital broadcast program data on a recording medium; Shifting a data reading speed from the recording medium to a high speed or a low speed corresponding to the speed requested for reproduction when the speed change reproduction request for the broadcast program data stored in the recording medium is requested; And And checking the picture start code and the picture coding type of the video elementary stream of the variable speed readout program data, selecting the base picture data, and intermittently or repeatedly restoring the base picture data. A trick play method for a digital broadcast receiver. delete The method of claim 1, In the step 3, the selected base image data is intermittently or repeatedly restored and output according to the requested playback speed, and the decoding operation of the audio and text data is paused in the digital broadcast receiver. How to play tricks.