KR100768950B1 - Digital broadcasting receive apparatus for reducing channel converting time and method thereof - Google Patents

Abstract

Disclosed are a digital broadcasting receiver and a channel switching method for minimizing channel switching time. The digital broadcasting receiver includes: a first transport stream demultiplexer (TSD) unit for separating a TS packet of a channel before a channel selection command is input; a second TSD unit for separating TS packets of a channel selected according to the channel selection command; And, if the channel selection command is input, it includes an MCE (Mpeg Core Engine) unit for decoding the first frame included in the TS packet of the selected channel subsequent to the last frame (frame) included in the TS packet of the previous channel. Accordingly, the channel switching time required for the user to use the digital broadcasting receiver can be minimized.

Channel switching, broadcasting signal, TS, frame, decoding, still picture

Description

Digital broadcasting receiving apparatus and channel switching method for minimizing channel switching time {digital broadcasting receive apparatus for reducing channel converting time and method

1 is a flowchart illustrating a channel switching method of a conventional digital broadcasting receiver;

2 is a block diagram showing a schematic configuration of a digital broadcasting receiver according to an embodiment of the present invention;

3 is a view for explaining a channel switching method of a digital broadcasting receiver according to an embodiment of the present invention;

4 is a diagram comparing a channel switching method of a digital broadcasting receiver according to an embodiment of the present invention, and

5 is a flowchart illustrating a channel switching method of a digital broadcasting receiver according to an embodiment of the present invention.

Explanation of symbols on the main parts of the drawings

100: tuner unit 110: 1st TSD unit

120: second TSD unit 130: memory unit

131: first channel buffer 133: second channel buffer

140: MCE unit 150: user command input unit

160: scaling unit 170: output unit

The present invention relates to a digital broadcasting receiver and a channel switching method for minimizing the channel switching time, and more particularly, the SI (System Information) information parsing time and input TS consumed during channel switching of the digital broadcasting receiver. The present invention relates to a digital broadcasting receiver and a channel switching method thereof which minimizes a channel switching time by reducing a decoding time of a transport stream.

In the digital broadcasting method, a broadcasting program is digitally compressed according to the MPEG2 standard at a broadcasting station and transmitted to a TS (Transport Stream) packet, and the digital broadcasting receiver receives the TS packet and then processes the signal to provide the user with an image and sound. It also provides various additional information.

In the header of the TS packet, SI (System Information) information including various kinds of information about a broadcast program is present, and Decoding Time Stamp (DTS) and PTS (PID) through PID (Packet IDentifier) information included in the SI information. You can find time information such as Presentation Time Stamp. Here, the DTS is a time for starting decoding after receiving the first frame included in the TS packet, and the PTS is a time for displaying the first decoded I frame on the screen. It is possible to decode the TS packet using this PID information.

1 is a flowchart illustrating a channel switching method of a conventional digital broadcasting receiver.

According to FIG. 1, first, when a channel selection command is input to a digital broadcasting receiver (S10), a broadcast program corresponding to the selected channel is tuned (S20). After parsing the PID information of the tuned broadcast program (S30), the TS packet of the tuned broadcast program is decoded using the PID information (S40). Finally, the decoded TS packet is signal processed and output to the screen as an image (S50).

In performing the conventional channel switching method, it takes about 1.5 to 2.8 s. That is, 0.6s for tuning the broadcast program corresponding to the selected channel, 0.2s for parsing the PID information, 1.7s for decoding the TS packet of the tuned broadcast program, and signal-processing the decoded TS packet to the screen. It takes about 0.328 seconds to output.

In addition, in the past, when a channel is switched, a broadcast program is not displayed on the screen, and a black screen is displayed or a message such as 'loading ...' or 'change channel is displayed.' As time goes on, you get bored.

Accordingly, an object of the present invention is to provide a digital broadcasting receiver and a channel switching method for minimizing channel switching time for reducing SI information parsing time and TS packet decoding time in order to reduce the time required for channel switching.

Another object of the present invention is to provide a digital broadcasting receiver and channel switching for minimizing channel switching time for continuously displaying the broadcast program of the previous channel and the broadcast program of the selected channel in order to alleviate the boredom felt by the user during channel switching. In providing a method.

According to an aspect of the present invention, there is provided a digital broadcast receiver according to the present invention, comprising: a first transport stream demultiplexer (TSD) unit for separating a TS packet of a channel before a channel selection command is input, and a channel selected according to the channel selection command; A second TSD unit for separating a TS packet of the second packet; and when the channel selection command is input, the second frame is decoded after the last frame included in the TS packet of the previous channel to decode the first frame included in the TS packet of the selected channel; It includes an MCE (Mpeg Core Engine) unit.

In addition, the digital broadcast receiver according to the present invention preferably further comprises a memory unit for storing the SI (System Information) information of the broadcast program corresponding to the channel selected according to the channel selection command.

The memory unit includes a second channel buffer through which a TS packet output from the second TSD unit is received, and the MCE unit includes a second channel buffer based on program map table (PMT) information included in the SI information. It is characterized by allocating capacity.

In addition, the digital broadcast receiver according to the present invention includes a scaling unit for scaling the last frame of the previous channel and the first frame of the selected channel decoded by the MCE unit, and the last frame of the previous channel scaled by the scaling unit. And an output unit for outputting the first frame of the selection channel.

The output unit may display the last frame of the previous channel and the first frame of the selected channel as a still picture.

On the other hand, the channel switching method of the digital broadcasting receiver according to the present invention comprises the steps of inputting a channel selection command, decoding the last frame of the TS (Transport Stream) packet of the channel before the channel selection command, the channel selection Separating the TS packets of the selected channel according to the command, and decoding the first frame included in the TS packet of the selected channel subsequent to the last frame included in the TS packet of the previous channel.

The method may further include storing SI (System Information) information of a broadcast program corresponding to a channel selected according to the channel selection command, and according to PMT (Program Map Table) information included in the SI information. The TS packet is characterized in that the capacity of the channel buffer to receive the allocation.

And scaling the last frame of the decoded previous channel and the first frame of the selected channel, and outputting the last frame of the scaled previous channel and the first frame of the selected channel. Do.

The outputting of the last frame of the previous channel and the first frame of the selected channel may be performed by displaying the last frame of the previous channel and the first frame of the selected channel as a still picture.

Hereinafter, with reference to the accompanying drawings will be described in detail an embodiment of the present invention. However, in describing the present invention, when it is determined that a detailed description of a related known function or configuration may unnecessarily obscure the subject matter of the present invention, the detailed description thereof will be abbreviated or omitted.

2 is a block diagram showing a schematic configuration of a digital broadcast receiving apparatus according to an embodiment of the present invention.

Referring to FIG. 2, the digital broadcast receiver includes a tuner unit 100, a first transport stream demultiplexer (TSD) unit 110, a second TSD unit 120, a memory unit 130, and an MPE (Mpeg Core Engine) unit. 140, a user command input unit 150, a scaling unit 160, and an output unit 170.

The tuner 100 tunes a digital broadcast signal transmitted in an ATSC (Advanced Television System Committee) method. That is, the tuner 100 tunes a broadcast signal corresponding to a channel selected by a user's channel selection command among the broadcast signals transmitted from the broadcasting station and outputs the tuned signal as a TS (Transport Stream) packet.

The first TSD unit 110 separates and outputs a TS packet corresponding to a channel before a channel selection command is input into a video packet, an audio packet, and an additional information packet.

The second TSD unit 120 separately outputs a TS packet of a selected channel tuned according to a channel selection command into a video packet, an audio packet, and an additional information packet.

The memory unit 130 stores SI (System Information) information of a broadcast program corresponding to the selected channel selected according to the channel selection command. SI information includes PMT (Program Map Table) information and PID (Packet IDentifier) information. In addition, the MCE unit 140 to be described later includes a first channel buffer 131 and a second channel buffer 133 required for decoding the TS packet. The TS packet corresponding to the previous channel output from the first TSD unit 110 is stored in the first channel buffer 131, and the TS packet of the selected channel output from the second TSD unit 120 is stored in the second channel buffer 133. Is stored.

The user command input unit 150 may include an operation key (not shown) necessary for receiving various user commands for controlling the operation of the digital broadcasting receiver or a light receiving unit (not shown) for receiving a signal transmitted from a remote controller (not shown). Equipped.

The scaling unit 160 scales and outputs the video signal decoded by the MCE unit 140, which will be described later, into resolutions such as 1080i, 720p, 480p, and 480i.

The output unit 170 displays the image signal output from the scaling unit 160 on the screen or outputs to an external display device (not shown).

When the channel selection command is input through the user command input unit 150, the MCE unit 140 decodes and outputs only the last frame included in the TS packet corresponding to the previous channel output from the first TSD 120. In this case, the MCE unit 140 uses the first channel buffer 131 and controls the scaling unit 160 and the output unit 170 to output the last frame of the previous channel as a still image.

In addition, the MCE unit 140 reads the SI information stored in the memory unit 130 before tuning the broadcast signal of the channel selected through the tuner unit 100. The second channel buffer 133 is allocated according to the PMT information so as to decode the broadcast program corresponding to the selected channel with reference to the read SI information. When the first frame of the selected channel is received by the second channel buffer 133, the MCE unit 140 decodes the first frame at the same time as the reception is completed.

Here, the first frame is an I frame, and among the frames received in the order of I, B, B, P, ..., if a P frame necessary to compose the screen is received, the MCE unit 140 displays the I frame on the screen. The scaling unit 160 and the output unit 170 are controlled to be displayed. At this time, since the time for switching to the last frame of the previous channel and the I frame, which is the first frame of the selected channel, is a short time of about 0.132 ms, the user may feel as if watching a continuous screen during channel switching.

Here, when the SI information of the broadcast program corresponding to the selected channel does not exist in the memory unit 130, the MCE unit 140 first tunes the broadcast signal corresponding to the selected channel through the tuner unit 100, The second TSD unit 120 is controlled to parse and store SI information existing in the header area of the TS packet in the memory unit 130.

When another channel selection command is input, the MCE unit 140 controls the second TSD unit 120 and the first TSD unit 110 to operate in reverse. That is, the second TSD unit 120 separates and outputs the TS stream of the previous channel, and the first TSD unit 110 separates and outputs the TS packet of the selected channel. The MCE unit 140 decodes and outputs the last frame of the second channel buffer 133, and then decodes the first frame when the first frame of the selected channel is received in the first channel buffer 131.

3 is a view for explaining a channel switching method of the digital broadcasting receiver according to an embodiment of the present invention.

Referring to FIG. 3, one GOP (Group Of Picture) includes a header (H) including SI information, the first frame (I ₁ ) of the selected channel, and the remaining frames (B ₂ , B ₃ , P) of the selected channel. ₄ , B ₅ , B ₆ , P ₇ , B ₈ , B ₉ , P ₁₀ , B ₁₁ , B ₁₂ ).

When the channel selection command is received, the MCE unit 140 refers to the PMT information included in the SI information pre-stored in the memory unit 130 and determines the capacity of the second channel buffer 133 by selecting the largest first frame of the channel. When buffering (I ₁ ), it is set to have a capacity that does not overflow. The first frame I ₁ of the selected channel output from the tuner 100 is received by the second channel buffer 133 and at the same time, the first frame I ₁ of the selected channel is decoded.

Herein, after the first frame I ₁ is received, the MCE unit 140 receives a fourth frame P ₄ among frames received in the order of B ₂ , B ₃ , P ₄ , B ₅ ,... When received by the second channel buffer 133, the scaling unit 160 and the output unit 170 are controlled to display the decoded first frame I ₁ on the screen.

In this case, the second and third frames (B ₂ , B ₃ ) are discarded because they are frames associated with unreceived frames, which are I frames before the first frame (I ₁ ), and are discarded and decoded from the fifth frame (B ₅ ). Is output. The first frame I ₁ is output as a still picture for 0.99 s until the fifth frame B ₅ is output on the screen. This is a very short time, and thus the user cannot recognize the still picture.

4 is a diagram comparing a channel switching method of a digital broadcasting receiver according to an embodiment of the present invention.

Referring to FIG. 4, conventionally, a broadcast program corresponding to a previous channel is displayed on a screen, and when a channel selection command is received, a loading screen is displayed on the screen for approximately 1.5 to 2.8 s and then corresponds to a selected channel. The program is displayed on the screen.

However, according to the digital broadcasting receiver according to the present invention, when a channel selection command is received, the first frame of the selected channel (Sel-channel First Frame: SFF) following the last frame (PLF) of the previous channel is received. ) Is displayed on the screen, which can significantly reduce the time required for channel switching.

Although not shown in FIG. 3, the black screen is displayed while the last frame (PLF) of the previous channel is switched to the first frame (SFF) of the selected channel, but this time is a short time of about 0.132 ms. When switching channels, you feel as if you are watching a series of screens.

5 is a flowchart illustrating a channel switching method of a digital broadcasting receiver according to an embodiment of the present invention.

Referring to FIG. 5, first, when a channel selection command is input (S200), the MCE unit 140 determines whether SI information of a broadcast program corresponding to the selected channel exists in the memory unit 130, and the SI information is stored in memory. If it is determined to exist in the unit 130 (S210), the SI information of the broadcast program corresponding to the selected channel from the memory unit 130 is read (S240).

On the other hand, if it is determined that the SI information of the broadcast program corresponding to the selected channel does not exist in the memory unit 130, after tuning the broadcast program corresponding to the selected channel (S220), parsing the SID information of the broadcast program ( parsing) and storing the same in the memory unit 130 (S230).

The MCE unit 140 sets the second TSD unit 120 and the second channel buffer 133 by using the SI information. That is, according to the PMT information included in the SI information, the capacity of the second channel buffer 133 is allocated to correspond to the size of the first frame I ₁ of the selected channel (S250).

The last frame of the previous channel is output as a still picture. That is, the MCE unit 140 controls only the display unit 160 to decode only the last frame of the previous channel and output the last frame of the previous channel as a still image (S260).

Then, the tuner unit 100 is controlled to tune the broadcast signal corresponding to the selected channel (S270), and when the fourth frame P ₄ is received by decoding the first frame I ₁ of the selected channel, the first frame is received. (I ₁ ) is output to the still image (S280). Thereafter, a broadcast program corresponding to the selected channel is output on the screen. That is, after decoding of the fifth frame B ₅ is completed, the fifth frame B ₅ and the remaining frames are displayed on the screen continuously (S290).

By the above process, it is possible to minimize the channel switching time of the digital broadcasting receiver. In the above description, the digital broadcasting receiver such as a television having a display function has been described. However, the present invention can also be applied to a digital broadcasting receiver such as a set-top box having no display function.

As described above, according to the present invention, the channel switching time for reducing the SI information parsing time and the decoding time of the input TS is minimized, and the channel switching is performed by continuously displaying the last frame of the previous channel and the first frame of the selected channel on the screen. You can avoid the time.

In addition, although the preferred embodiment of the present invention has been shown and described above, the present invention is not limited to the above-described specific embodiment, the technical field to which the invention belongs without departing from the spirit of the invention claimed in the claims. Anyone of ordinary skill in the art that various modifications can be made, as well as such changes are within the scope of the claims.

Claims (10)

A first Transport Stream Demultiplexer (TSD) unit that separates a TS packet of a channel before a channel selection command is input; A second TSD unit separating a TS packet of a channel selected according to the channel selection command; And A MCE (Mpeg Core Engine) unit for decoding the first frame included in the TS packet of the selected channel subsequent to the last frame included in the TS packet of the previous channel when the channel selection command is input; Digital broadcasting receiver, characterized in that. The method of claim 1, And a memory unit for storing SI (System Information) information of a broadcast program corresponding to a channel selected according to the channel selection command. The method of claim 2, The memory unit, And a second channel buffer through which the TS packet output from the second TSD unit is received. The MCE unit allocates the capacity of the second channel buffer according to the PMT (Program Map Table) information included in the SI information. The method of claim 1, A scaling unit for scaling the last frame of the previous channel and the first frame of the selected channel decoded by the MCE unit; And And an output unit for outputting the last frame of the previous channel and the first frame of the selected channel scaled by the scaling unit. The method of claim 4, wherein The output unit, And displaying the last frame of the previous channel and the first frame of the selected channel as a still picture. Inputting a channel selection command; Decoding a last frame of a transport stream (TS) packet of a channel before the channel selection command is input; Separating TS packets of the selected channel according to the channel selection command; And And decoding the first frame included in the TS packet of the selected channel subsequent to the last frame included in the TS packet of the previous channel. The method of claim 6, And after the separating of the TS packet, storing SI (System Information) information of a broadcast program corresponding to a channel selected according to the channel selection command. The method of claim 7, wherein And allocating capacity of a channel buffer in which the TS packet of the selected channel is received according to PMT (Program Map Table) information included in the SI information. The method of claim 6, After decoding the first frame, scaling a last frame of the decoded previous channel and a first frame of the selected channel; And After the scaling, outputting a last frame of the previous channel and a first frame of the selected channel. The method of claim 9, Outputting the last frame of the previous channel and the first frame of the selected channel, And displaying the last frame of the previous channel and the first frame of the selected channel as a still picture.

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