JP2007013826A - Video image receiving device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a video image receiving device, capable of shortening a non video image (blackout) period upon switching a receiving channel. <P>SOLUTION: The video image receiving device is provided with a plurality of series of tuners and decoders, while the channels of systems which are not used for viewing and listening are checked periodically to store images, decoded in respective channels in a memory, sequentially together with a header information. When switching of channel is generated, the image of a specified channel stored in the memory is precedingly displayed, until the system of normal viewing and listening becomes enabled to output the video image of the specified channel. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a video receiving apparatus that receives digital television broadcasts.

  In a video receiving apparatus compatible with digital television broadcasting, a signal received by an antenna is demodulated into TS data by a tuner, and video / audio PES data of a viewing channel is separated by a TS separator. The separated PES is supplied to an AV decoder, and the video / audio compressed by the MPEG method is decoded and output as a video / audio signal.

  This conventional video receiving apparatus has a problem that a non-video (blackout) period of 1 second or more occurs when the reception channel is switched. This is mainly because it takes time to stabilize the demodulation process of the tuner, to acquire sequence header information in video decoding, and to wait for video / audio synchronization.

  In general, it is said that if there is a time lag of 0.5 seconds or more from when the user selects a channel until it is displayed, the user feels stress on the operability. In order to cope with this problem, as an example of the conventional technique, there is a technique of a receiving apparatus that attempts to shorten a non-video period (see, for example, Patent Document 1).

In an example of this prior art, two channels of tuners and TS separators are used, and a TS number of seconds for each channel is obtained cyclically using a system that is not received by normal viewing and stored in a memory. At the time of channel switching, the non-video period is shortened by decoding and outputting the stored TS until the normal viewing system can output.
JP 2001-309255 A

  However, in the above prior art example, since the stored TS is decoded and output, it takes time to decode this TS, and the non-video period is not sufficiently shortened.

  In view of the above problems, an object of the present invention is to provide a video receiver capable of sufficiently shortening the non-video period at the time of channel switching.

  In order to solve the above problems, a video receiving apparatus according to the present invention stores a main tuner and decoder that receive a channel for normal viewing, a sub tuner and decoder that receives a channel that is not normally viewed, and a decoded image. A memory unit that periodically circulates reception channels by the sub-system tuner and decoder, stores images decoded by each channel in the memory unit, and designates by the main system tuner and decoder when the reception channel is switched The decoded image corresponding to the designated channel is displayed until a video of the selected channel is displayed.

  According to the present invention, the no-video (blackout) period at the time of channel switching can be greatly shortened, and the user's stress on operability can be reduced.

(Embodiment 1)
FIG. 1 is a block diagram showing a configuration of an embodiment of a video receiving apparatus according to the present invention. Hereinafter, embodiments of the present invention will be described with reference to this figure.

  In FIG. 1, a tuner A11 is a main (normal viewing) tuner unit, and a tuner B12 is a sub (non-normal viewing) tuner unit, which demodulates the received signal of each channel to obtain a TS. TS separation A21 is a main system TS separation unit, and TS separation B22 is a sub system TS separation unit, which extracts video PES data of each channel. The decoder A31 is a main system decoding unit, and the decoder B32 is a sub system decoding unit, which performs decoding processing of the separated TS video images.

  The memory unit 101 stores the image and image information obtained by the decoder B32. The video switching unit 41 switches between the viewing video by the decoder A31 and the image stored in the memory unit 101, and displays either of them on the video output unit 51.

  Further, the control unit 100 sets a channel for reception processing in the main system configuration (tuner A11, TS separation A21, decoder A31) and a channel for reception processing in the sub system configuration (tuner B12, TS separation B22, decoder B32). And switching of output display in the video switching unit 41 is controlled.

  First, the operation during normal viewing in the above configuration will be described. FIG. 2 is a time chart showing the flow of processing during normal viewing according to the embodiment of the present invention.

  The control unit 100 controls the main system configuration (tuner A11, TS separation A21, decoder A31) to process a user-specified viewing channel. In this figure, it is assumed that channel 1 is viewed as an example. At this time, the switching unit 41 and the video output unit 51 are controlled so as to output the video of the viewing channel. In the case shown in this figure, video 1 which is the contents of channel 1 is output.

  Further, for the sub system configuration (tuner B12, TS separation B22, decoder B32), control is performed so that all channels are periodically switched and processed. In this figure, channels 1 to 6 are circulated. At this time, the reference image and image information (such as header parameters) of each channel decoded in the sub system are sequentially stored in a predetermined area of each channel of the memory unit 101. In the example shown in the figure, areas 1 to 6 correspond to the predetermined area.

  Note that although the sub system processing targets are all channels here, this may be limited to a channel group with high viewing frequency. In this configuration, one sub system is used, but a plurality of systems may be used to share channels for cyclic processing.

  Next, the operation at the time of channel switching will be described. FIG. 3 is a time chart showing the flow of processing at the time of CH switching according to the embodiment of the present invention. Prior to the timing indicated by the arrow as “switch occurrence” in this figure (the left side of the broken line) is as described with reference to FIG.

  When channel switching occurs, the control unit 100 first changes the processing channel of the main system configuration (tuner A11, TS separation A21, decoder A31) to a designated channel. In the example shown in this figure, the channel 1 is switched to the channel 2.

  At the same time, the video switching unit 41 switches the output target to the decoded image of the designated channel stored in the memory 101. In this example, since channel 2 is the designated channel, the corresponding decoded image is stored in area 2 of the memory unit 101, so it is read out and stored in the area in the video output unit 51. The image that has been displayed will be displayed. Here, since the decoded image is already stored in the memory unit 101, the decoding time is not necessary and the image is displayed immediately, and there is almost no non-video period.

  When the control unit 100 detects that the video output of the decoder A31 is possible through the transition state, the control unit 100 changes the output target in the video switching unit 41 to the main system viewing video. In the example shown in this figure, the video of channel 2 is displayed. Thereafter, the operation during normal viewing is performed with channel 2 as the designated channel.

  Here, the images stored in the memory unit and displayed in advance may be single or plural (image sequence). Further, when switching from the previously displayed image to the viewing video, special processing such as fade-in (gradually displaying the image) for reducing unnaturalness may be added.

  With the above-described configuration and operation, according to the video display device of the present invention, the pre-decoded image is displayed in advance during the channel switching transition period. Can be shortened.

  Furthermore, an example in which the images of each channel stored in the memory unit 101 are used in the electronic program guide (EPG) and the back program list display will be described with reference to FIG.

  When a viewer switches channels, there are cases in which, in addition to selecting a channel to be switched directly, an electronic program guide is displayed and a channel to be switched from there is selected. At that time, according to the video display device of the present invention, not only the program table is composed of the EPG data multiplexed on the broadcast wave or the EPG data acquired from the Web or the like, but as shown in FIG. For the program being broadcast, its image is also displayed in the program guide. In this image display, together with program information of each channel, the image is read from the memory unit 101 and synthesized and displayed.

  As described above, since the decoded image of each channel is stored in the memory unit 101 for the currently broadcast program, the composite display is smoothly performed and the period of no video is greatly reduced. it can. Also, the channel to be switched by the EPG is selected, the processing channel of the main system configuration (tuner A11, TS separation A21, decoder A31) is changed to the designated channel, and the switching period until the video of this channel is displayed. If the previously decoded image is displayed in advance as described above, the no-video (blackout) period can be greatly shortened.

  Also, with the sub system configuration (tuner B12, TS separation B22, decoder B32), all channels are cyclically switched and the reference image and image information of each decoded channel are stored in a predetermined channel of the memory unit 101. Since the programs are sequentially stored in these areas, the back program can be displayed as a list as shown in FIG. This image display is the same as that in the case of the above EPG display, and the channel switching operation is also the same, so the description thereof is omitted.

  Although the present embodiment has been described with reference to the time charts of FIGS. 2 and 3, the channels 1 to 6 and areas 1 to 6 in the description are specific examples of the operation, and the present invention is only specific examples It is not limited to.

  The video receiving apparatus according to the present invention can significantly reduce the non-video period at the time of channel switching, and is useful in a video receiving apparatus that receives and displays a digital signal.

The block diagram which shows the structure which concerns on embodiment of this invention Time chart showing the flow of processing during normal viewing according to an embodiment of the present invention The time chart which shows the flow of the process at the time of CH switching which concerns on embodiment of this invention The figure which shows an example of the screen display which concerns on embodiment of this invention

Explanation of symbols

11 Tuner A (Main tuner)
12 Tuner B (Sub-system tuner)
21 TS separation A (TS separation section of the main system)
22 TS separation B (sub system TS separation section)
31 Decoder A (decoding section of main system)
32 Decoder B (Sub system decode part)
41 Video switching unit 51 Video output unit 100 Control unit 101 Memory unit

Claims (2)

A main tuner and decoder for receiving a normal viewing channel, a sub tuner and decoder for receiving a non-normal viewing channel, and a memory unit for storing decoded images;
The reception channel is periodically circulated by the sub-system tuner and decoder, and an image decoded in each channel is stored in the memory unit,
A video receiving apparatus, wherein the decoded image corresponding to the designated channel is displayed during a period until the video of the channel designated by the main tuner and decoder is displayed when the reception channel is switched. 2. The video receiving apparatus according to claim 1, wherein when displaying the electronic program guide or the back program list, the decoded image of each channel stored in the memory unit is displayed together with program information.

Images