JP2007174013A - Digital broadcasting receiver - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a digital broadcasting receiver capable of returning to a data broadcasting screen of an original channel, even if a channel is changed during viewing of data broadcasting. <P>SOLUTION: A data broadcasting document decoded by a data decoding means 6 is supplied to a data broadcasting browser 9 forming the data broadcasting screen. When a channel switching signal is inputted during broadcasting of a data broadcasting content; a browser control means 13 gives an instruction of channel switching to a receiving means 1 and a multiplex separation means 3 after detecting zapping, gives an instruction of state retention to a document analysis means 11 that outputs layout information for forming the data broadcasting screen, and also, gives an instruction of initialization to a layout drawing means 12 for forming the data broadcasting screen. When it is returned to the channel at the time when a channel switching signal is inputted, the browser control means 13 gives an instruction of validation to the layout drawing means 12 while giving an instruction of release of the state retention to the document analysis means 11. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a digital broadcast receiver that can return to the data broadcast screen that was being viewed when the channel is returned to the original channel and continue to view even if a channel zapping operation is performed during the viewing of the data broadcast. .

  With the practical application of digital broadcasting, various data broadcasts are being broadcast and various data broadcast contents are being viewed. In order to receive data broadcasting, the channel is set to the desired channel and then the d button is pressed to move to the target page (or display state), which is a relatively complicated operation. Need. On the other hand, if you change the channel while watching the data broadcast, you will not return to the original data broadcast screen, so if you want to watch the data broadcast before changing the channel again, start over from the beginning. It will move to the target page.

  In many cases, while viewing various broadcast contents, a remote program is operated to temporarily view broadcast programs on other channels. For example, when a desired broadcast program is selected, there are many cases in which a desired broadcast program is selected by sequentially changing channels by zapping. In some cases, zapping is performed during a commercial period to check other broadcast programs. Thus, the zapping operation is widely used as a simple method when the viewer selects a desired channel.

  In a conventional digital broadcast receiver, when a zapping operation is performed during viewing of a data broadcast to temporarily view a broadcast program of another channel, the d broadcast button is pressed again because the program does not return to the data broadcast screen immediately before zapping. It was necessary to redo the operation. However, since the operation of the data broadcast screen is relatively complicated, it has been a heavy burden on the viewer when it is desired to continue watching the original data broadcast. Such a burden on the viewer is an obstacle to the utilization of the data broadcast, and cannot sufficiently respond to the demand of the viewer who desires to continuously view the data broadcast.

An object of the present invention is to provide a digital broadcast receiver that returns to the data broadcast screen of the original channel even if the channel is changed during viewing of the data broadcast.
Another object of the present invention is to provide a digital broadcast receiver that automatically returns to the data broadcast screen at the start of zapping when zapping is completed or stopped.

A digital broadcast receiver according to the present invention comprises a receiving means for receiving a channel selection signal and selecting a TV signal of a designated channel;
Demodulating means for demodulating the TV signal of the selected channel and outputting a digital signal stream;
Demultiplexing means for outputting an audio signal stream, a video signal stream, and a data signal stream, respectively, and a data decoding means for decoding the data signal stream and outputting a data broadcast document from the digital signal stream;
A data broadcast browser for receiving the data broadcast document and forming a data broadcast screen;
In a digital broadcast receiver comprising control means for controlling the above means,
The data broadcast browser receives the data broadcast document and outputs a layout information for forming a data broadcast screen, a layout analysis unit that receives the layout information and forms a data broadcast screen, and a document analysis Browser control means for controlling the means and layout drawing means,
When a channel switching signal is input during viewing of data broadcasting content, the browser control means instructs the document analysis means to hold a state and instructs the layout drawing unit to initialize,
When returning to the channel at the time when the channel switching signal is input, the browser control means instructs the document analysis means to cancel the state holding and instructs the layout drawing means to validate. To do.

  In the present invention, when a channel switching signal is input from the remote control while viewing a data broadcast of a predetermined channel, the control means detects that the operation has shifted to the zapping operation, and the browser control means maintains a state for the document analysis means. Instruct. Thereafter, when the channel is switched and the channel returns to the channel at the start of zapping, the control means detects the end of zapping, and the browser control means instructs the document analysis means to cancel the state holding. As a result, the data broadcast of the channel immediately before the channel is switched is displayed. When the browser control unit instructs the document analysis unit to maintain the state, the browser control unit accepts an internal command for forming an internal signal and maintains an external command from a remote controller or the like. The

A second digital broadcast receiver according to the present invention comprises a receiving means for receiving a channel selection signal and selecting a TV signal of a designated channel;
Demodulating means for demodulating the TV signal of the selected channel and outputting a digital signal stream;
Demultiplexing means for outputting an audio signal stream, a video signal stream, and a data signal stream, respectively, and a data decoding means for decoding the data signal stream and outputting a data broadcast document from the digital signal stream;
A data broadcast browser for receiving the data broadcast document and forming a data broadcast screen;
In a digital broadcast receiver comprising control means for controlling the above means,
The data broadcast browser receives the data broadcast document and outputs a layout information for forming a data broadcast screen, a layout analysis unit that receives the layout information and forms a data broadcast screen, and a document analysis Browser control means for controlling the means and layout drawing means,
When a signal for instructing zapping is input during viewing of the data broadcasting content, the control means instructs the receiving means to sequentially switch channels, and the browser control means instructs the document analysis means. Instructing the state drawing to the layout and instructing the layout drawing unit to initialize,
When a signal for instructing the end of zapping is input, the control means instructs the receiving means to switch to the channel immediately before zapping, and the browser control means instructs the document analysis means to maintain the state. The release is instructed, and the layout drawing means is instructed to validate.

The digital broadcast receiver relates to a digital broadcast receiver provided with a zapping button for generating an input signal instructing a zapping operation. In the digital broadcast receiver, when a zapping signal for instructing the start of zapping is input via the remote controller, the document analysis unit of the data broadcast browser holds the internal command and does not accept the external command, and the zapping end signal When this occurs, the document analysis means is instructed to cancel the state. As a result, when zapping is completed, the screen returns to the data broadcasting screen when zapping is disclosed. In the present specification, “sequentially switching channels” includes both cases where channels are switched in descending order and ascending order according to a predetermined order, and channels are switched randomly.

Another digital broadcast receiver according to the present invention comprises a receiving means for receiving a channel selection signal and selecting a TV signal of a designated channel;
Demodulating means for demodulating the TV signal of the selected channel and outputting a digital signal stream;
Demultiplexing means for outputting an audio signal stream, a video signal stream, and a data signal stream, respectively, and a data decoding means for decoding the data signal stream and outputting a data broadcast document from the digital signal stream;
A data broadcast browser for receiving the data broadcast document and forming a data broadcast screen;
In a digital broadcast receiver comprising control means for controlling the above means,
The data broadcast browser receives the data broadcast document and outputs a layout information for forming a data broadcast screen, a layout analysis unit that receives the layout information and forms a data broadcast screen, and a document analysis Browser control means for controlling the means and layout drawing means,
The document analysis means includes first and second document analysis units that switch between the active system and the standby system,
When zapping is detected or a signal instructing zapping is input, the browser control means instructs the first document analysis unit of the active system to hold the state and switches from the active system to the standby system. Switch the second document analysis unit to the active system,
When the end or stop of zapping is detected, the browser control means switches the active second document analysis unit to the standby system and switches the standby first document analysis unit to the active system. To do.

  In the digital broadcast receiver, document analysis means for outputting layout information for forming a data broadcast screen is composed of two systems of document analysis units. Therefore, each time zapping is detected, the document analysis unit is used as an active system. By switching between the standby system and the standby system, it is possible to automatically return to the data broadcasting screen at the time of starting zapping at the end of zapping. Further, by having the two systems of document analysis units, the advantage that it is possible to view the data broadcast of the channels that are sequentially switched even during the zapping period is achieved.

In a preferred embodiment of the digital broadcast receiver, the layout drawing means further includes first and second layout drawing units that switch between an active system and a standby system,
When zapping is detected or a signal instructing zapping is input, the browser control means instructs the first document analysis unit of the active system to hold the state, and the first document analysis unit and the first document analysis unit The layout drawing unit is switched to the standby system, the standby second document analysis unit and the second layout drawing unit are switched to the active system,
When the end or cancellation of zapping is detected, the browser control means switches the active second document analysis unit and the second layout drawing unit to the standby system, and sets the standby first document analysis unit and the second document analysis unit. One layout drawing unit is switched to an active system. In this example, since there are two systems of layout drawing means, the advantage of shortening the return time to the original data broadcast screen is achieved.

Another digital broadcast receiver according to the present invention comprises a receiving means for receiving a channel selection signal and selecting a TV signal of a designated channel;
Demodulating means for demodulating the TV signal of the selected channel and outputting a digital signal stream;
Demultiplexing means for outputting an audio signal stream, a video signal stream, and a data signal stream, respectively, and a data decoding means for decoding the data signal stream and outputting a data broadcast document from the digital signal stream;
A data broadcast browser for receiving the data broadcast document and forming a data broadcast screen;
Control means for controlling each of the above means,
The data broadcast browser receives the data broadcast document and outputs a layout information for forming a data broadcast screen, a layout analysis unit that receives the layout information and forms a data broadcast screen, and a document analysis In a digital broadcast receiver having browser control means for controlling the means and layout drawing means,
The receiving means, demodulating means, demultiplexing means, data decoding means, and document analysis means each have first and second systems that are alternately switched between the active system and the standby system,
When zapping is detected or a signal instructing zapping is input, the first system means of the working system is switched to the standby system, and the second system means of the standby system is switched to the working system.
When the end of zapping is detected, the second system means is switched to the standby system, and the first system means is switched to the active system.

  The digital broadcast receiver achieves the advantage of being able to completely follow even if the data broadcast state changes during zapping.

  In the digital broadcast receiver according to the present invention, it is possible to take an appropriate countermeasure according to the state change in consideration of the state change of the data broadcast between the time of starting zapping and the end of zapping. As means for detecting a change in state of the data broadcast, for example, whether or not the data broadcast is updated at the start of zapping or whether or not the BML document is updated can be used. In addition, when a state change is not recognized, it can return to the data broadcast at the time of zapping disclosure, and when a state change is recognized, for example, it can be set to execute the data broadcast from the initial state.

  In the present invention, when zapping is detected from the channel switching signal, it is configured to automatically return to the data broadcast screen when returning to the original channel, or after the zapping signal is input and zapping is started, the zapping ends. When a signal is input, the channel automatically returns to the data broadcasting screen of the channel at the start of zapping, so that even if a zapping operation is performed during viewing of the data broadcast, the original data broadcast can be automatically viewed. As a result, it is possible to continue viewing the data broadcast without performing a complicated data broadcast operation.

  FIG. 1 is a diagram showing the basic configuration of a digital broadcast receiver according to the present invention. A TV signal such as an RF signal or an IF signal is channel-selected in the receiving unit 1, frequency-converted, and output to the demodulating unit 2. The demodulator 2 demodulates the TV signal of the selected channel and outputs a digital signal stream. For example, in the case of terrestrial digital broadcasting, the TV signal (IF signal) is an ISDB-T signal, and the demodulator 2 performs OFDM demodulation on the ISDB-T signal and outputs an MPEG-2 transport stream as a digital signal stream. The digital signal stream is input to the demultiplexing unit 3, separated into an audio signal stream, a video signal stream, and a data signal stream, and input to the audio decoding unit 4, the video decoding unit 5, and the data decoding unit 6. The audio signal stream input to the audio decoding unit 4 is decoded (decoded), and a TV audio signal is output. The video decoding unit 5 decodes the video signal stream, and outputs a TV video signal through the reduced layout unit 7 and the video synthesis unit 8. The data decoding unit 6 decodes the input data signal stream to generate a data broadcast document, and outputs the data broadcast document to the data broadcast browser 9. In the case of terrestrial digital broadcasting, the data decoding unit 6 decodes a data carousel transmitted as a data signal stream, and outputs a resource (file) of the data broadcasting document. The data broadcast browser 9 decodes the input data broadcast document to generate a data broadcast video signal to be displayed on the layout, and outputs the data broadcast video signal to the video composition unit 8. The video synthesis unit 8 synthesizes the TV video signal output from the video decoding unit 5 and the data broadcast video signal output from the data broadcast browser 9 and outputs a video signal.

  The receiver control unit 10 is configured to receive a receiving unit 1, a demodulating unit 2, a decoding unit 3, an audio decoding unit 4, a video decoding unit 5, a data decoding unit 6, and a data decoding unit 6 based on a receiver operation such as channel switching input via a remote controller. The data broadcasting browser 9 is controlled.

  The data broadcast browser 9 includes a document analysis unit 11, a layout drawing unit 12, and a browser control unit 13. The document analysis unit 11 interprets the input data broadcast document, generates a layout command instructing the layout of the data broadcast screen, and outputs the layout command together with the data broadcast document displayed on the screen to the layout drawing unit 12. The document analysis unit 11 has a function of temporarily storing the input data broadcast document, creating an internal document for generating a layout command, and temporarily storing the created internal document. The layout drawing unit 12 lays out and draws the data broadcast document based on the layout information supplied from the document analysis unit 11 to generate a data broadcast screen. Further, the layout drawing unit 12 supplies video layout information for laying out the TV video to the video reduction layout unit 7. The browser control unit 13 receives the control signal from the receiver control unit 10 and the data broadcast operation signal from the remote control, instructs the document analysis unit 11 based on the document analysis, An invalidation command is transmitted to instruct the execution of layout and drawing processing and the cancellation of the execution.

  The video reduction layout unit 7 performs layout of the TV video signal that is a part of the layout of the data broadcast. Therefore, based on the layout information for the TV video supplied from the layout drawing unit 12 of the data broadcast browser, the video reduction layout unit 7 Perform placement.

  The video synthesis unit 8 synthesizes the TV video output from the video reduction layout unit 7 and the data broadcast video output from the data broadcast browser, and outputs a video signal.

  Next, the channel switching operation of the digital broadcast receiver shown in FIG. 1 will be described. The receiver control unit 10 receives the channel switching signal sent from the remote controller, and receives the target channel (frequency channel for the receiving unit 1 and the demultiplexing unit 3 via the receiving unit 1 and the demultiplexing unit 3). Instructs to select (Knitting channel). At the same time, the browser controller 13 of the data broadcast browser 9 is instructed to perform initialization. Further, if necessary, the demodulation unit 2, the audio decoding unit 4, the video decoding unit 5 and the data decoding unit 6 are instructed to perform initialization and the like. Under the control of the receiver control unit, the audio signal and video signal of the newly switched channel are output.

  Next, the operation during zapping will be described. As a zapping operation, a zapping instruction button for instructing the start and end of zapping is provided on the remote control, and when the viewer presses the zapping button, the zapping mode is entered, and when the viewer switches the channel while watching the data broadcast. A case will be described in which the receiver side automatically determines that it is in the zapping mode when a new data broadcast is not viewed.

First, a description will be given of processing when it is determined that zapping is automatically performed on the receiver side in response to channel switching by the remote control operation of the viewer. When a channel switching instruction is input from the remote controller while viewing the data broadcast, the receiver control unit 10 and the browser control unit detect zapping. In response to detection of this zapping, the receiver controller selects a new channel for the receiver 1 and the demultiplexer 3 (frequency channel for the receiver and organization for the demultiplexer). Channel). At the same time, it instructs the data broadcast browser 9 to switch channels. In response to this channel switching instruction, the browser control unit 13 instructs the document analysis unit 11 to hold a state and instructs the layout drawing unit 12 to invalidate the state. As a result, the document analysis unit 11 maintains the state of the temporary storage of the broadcast document sent from the data decoding unit, and continues the process of the temporary storage of the internal command. That is, (a command from the remote control) external command is not accepted, the execution of an internal command (command included in the data broadcast its timer over events, etc.) continues. On the other hand, the layout drawing unit 12 is initialized, and the data broadcast screen is blank (data broadcast document is not displayed). At the same time, video layout information is sent to the video reduction layout unit 7 so as to be a full-screen TV video, and finally a full-screen TV video is output. This state is continuously maintained, and the data broadcast browser maintains this state even when the channel is switched, except when a condition described later is satisfied.

  When the channel is switched to return to the original state (a state in which the channel is returned to the original channel immediately before zapping), the receiver control unit detects the end or stop of zapping and performs the following operation on the data broadcasting browser. Instruct. The browser control unit 13 instructs the document analysis unit 11 to cancel the state holding and instructs the layout drawing unit 12 to validate. Thereby, the document analysis unit 11 starts to fetch the data broadcast document newly decoded by the data decoding unit 6 for the temporary storage processing of the data broadcast document, and creates and temporarily stores the internal document for generating the layout command. For, continue execution of internal commands and resume execution of external commands. On the other hand, the layout drawing unit 12 is activated and performs layout and drawing of the data broadcast screen. At the same time, the video reduction layout unit 7 sends video layout information to the video reduction layout unit 7. Finally, a video signal in which the TV video and the data broadcast screen are synthesized is output from the video synthesis unit 8. In this way, the data broadcast screen immediately before channel switching is displayed.

  On the other hand, when the data broadcast button is pressed without returning to the original channel, zapping is stopped, and the normal channel switching process is started, and the browser control unit 13 initializes the document analysis unit and the layout drawing unit. And data broadcasting of a new channel is executed from the initial state.

  Thus, even when a zapping operation is performed, the content can be continuously viewed from the state of the original data broadcast screen by returning to the original channel unless data broadcast is performed on the zapped channel.

  When returning to the original channel, the newly decoded document is compared with the document before switching the channel, and if the version has changed or the document structure is different, It is possible to introduce exception processing such as determining that it is difficult to continuously display data broadcasting, or determining that there is a possibility of failure, and initializing the data broadcasting browser.

  Next, a process in the case where an explicit zapping instruction is given from the viewer, that is, a zapping instruction button provided on the remote controller is pressed will be described. Note that channel switching is performed according to normal operations and operations. When zapping input is performed from the viewer via the remote controller, the receiver control unit 10 instructs each function or means to perform zapping and instructs to perform channel switching processing. At the same time, the channel identification information immediately before zapping input is stored. The receiver control unit instructs the data broadcasting browser 9 in the zapping state. The browser control unit 13 of the data broadcast browser 9 instructs the document analysis unit 11 to hold the state, and instructs the layout drawing unit 12 to invalidate it. As a result, the document analysis unit maintains the state of the temporary storage of the data broadcast document, and the internal document creation and temporary storage are continuously executed. That is, external commands are not accepted, and internal commands are continuously executed. In addition, the layout drawing unit is initialized and the data broadcast is not displayed on the screen. At the same time, video layout information to be a full-screen TV video is sent from the layout drawing unit to the video reduction layout unit 7, and finally the full-screen TV video is output from the video composition unit 8.

  When the zapping end button is pressed during channel switching and zapping is completed, the receiver control unit instructs each component or means to end or stop zapping. The receiver control unit instructs the receiving unit and the demultiplexing unit to select the stored zapping start channel and instructs the data broadcasting browser to cancel the zapping state. Upon receiving this zapping cancellation instruction, the browser control unit 13 instructs the document analysis unit 11 to cancel state retention, and instructs the layout drawing unit 12 to validate. As a result, the document analysis unit 11 resumes taking in the newly decoded document for temporary storage of the data broadcasting document, and continues execution of internal commands for creation and temporary storage of the internal document when there is no change in the document. To do. When the document is changed, the internal document is created again. That is, acceptance of an external command that is a command from the remote controller is started, and execution of an internal command that is a command generated by the data broadcast itself is continued. On the other hand, the layout drawing unit 12 is activated, and the data broadcast screen is laid out and drawn. At the same time, video layout information on which a TV video is to be reduced and laid out is sent to the video reduction layout unit 7. As a result, the video broadcasting screen immediately before the zapping start (the screen corresponding to the change) and the TV video screen are synthesized and output from the video synthesizing unit 8. In this way, even when zapping is performed, it is possible to return to the original channel and continuously view the content from the state of the original data broadcast screen.

  If zapping is stopped and the data broadcast button is pressed before returning to the original data broadcast screen to select a data broadcast of another channel, the browser control unit 13 causes the document analysis unit 11 and the layout drawing unit 12 to be selected. , And data broadcasting of a new channel is executed from the initial state.

  When moving to the original data broadcast screen display, the newly decoded document is compared with the document before switching the channel, and if the version has changed or the document structure is different, the switch is made. It is possible to introduce exception processing such as determining that it is difficult to continuously display the previous data broadcast, or determining that there is a possibility of failure, and initializing the data broadcast browser.

  FIG. 2 is a diagram showing a second embodiment of the digital broadcast receiver according to the present invention. The same components as those used in FIG. 1 are denoted by the same reference numerals, and the description thereof is omitted. In this example, as the document analysis unit 20, there are provided two types of document analysis units, a first document analysis unit and a second document analysis unit. The rest is the same as the digital broadcast receiver shown in FIG. When the start of zapping is instructed, the receiver control unit 10 instructs the receiving unit 1 and the demultiplexing unit 3 to switch to a new channel and instructs the data broadcasting browser 13 to perform zapping. Upon receiving the zapping instruction, the browser control unit 13 saves the first document analysis unit in the active state (active system) in the backup system, and uses the second document analysis unit in the save state (standby system). Switch to the system. By this switching, the first document analysis unit maintains the state for the temporary storage function of the data broadcast document, and continuously executes the function for creating and temporarily storing the internal document. That is, the external command is not accepted, and the internal command is switched to a state where execution is continued. On the other hand, using the second document analysis unit that has become the active system, a sequential switching display of channels including data broadcasting is performed. At this time, the layout drawing unit continues the effective operation state.

  When the zapping is completed, the receiver control unit 10 is instructed to end the zapping. In response to this, the receiver control unit 10 instructs the receiving unit 1 and the demultiplexing unit 3 to select the channel immediately before starting zapping and instructs the data broadcasting browser 9 to cancel the zapping state. To do. Upon the cancellation of the zapping state, the browser control unit 13 switches the second document analysis unit from the active state (active system) to the save state (standby system), and returns the first document analysis unit from the save state to the active state. Let In this way, by switching from the first system to the second system, the first document analysis unit starts taking in the newly decoded document, and the internal document creation and temporary storage functions are controlled by the internal command. Continue execution. As a result, the layout drawing unit 13 starts laying out and drawing the data broadcast screen, the video layout information is also supplied to the video reduction layout unit 7, and finally, the data broadcast screen and the TV video screen are displayed from the video composition unit 8. Synthesized and output. In this way, the data broadcast screen immediately before the start of zapping is displayed.

  On the other hand, when the zapping is stopped without returning to the original data broadcast screen, the data broadcast is presented while the second document analysis unit is set to be active. Further, when a new zapping is started from this state, the second document analysis unit is saved and the first document analysis unit is set to be active and data broadcasting is presented.

  In the second embodiment, it is possible to display a data broadcast even during zapping. In the first embodiment, since the state of the document analysis unit is maintained during zapping, the function as a data broadcasting browser cannot be used as a whole. On the other hand, in the second embodiment, instead of the first document analysis unit holding the state, another document analysis unit switched to the active system executes the process, so that the data broadcasting browser as a whole Can continue as a function.

  When returning to the original data broadcasting screen after the completion of zapping, the newly decoded document is compared with the document before switching the channel, and the version has changed or the document structure is different. Can perform the exception handling described above.

  FIG. 3 is a diagram showing a third embodiment of the digital broadcast receiver according to the present invention. In addition, the same code | symbol is attached | subjected about the component same as the component used in FIG. 1, and the description is abbreviate | omitted. In this example, the document analysis unit 30 includes first and second document analysis units that are switched between the active system and the standby system, and the layout drawing unit 31 is also switched between the active system and the standby system. The first and second layout drawing sections are provided to enable reception of data broadcast of the current channel even during zapping and to shorten the return time from zapping to the original channel.

  When the start of zapping is detected by the channel switching signal or the zapping instruction signal, the receiver control unit 10 instructs the receiving unit 1 and the demultiplexing unit 3 to switch to a new channel, and the data broadcasting browser. 13 is instructed to zapping. Upon receiving the zapping instruction, the browser control unit 13 saves the first document analysis unit that has been currently used, and switches the second document analysis unit that has been in the save state to the active system. By this switching, the first document analysis unit maintains the state for the temporary storage function of the data broadcast document, and continuously executes the function for creating and temporarily storing the internal document. That is, the external command is not accepted, and the internal command is switched to a state where execution is continued. On the other hand, the channel including data broadcasting is sequentially presented by using the second document analysis unit which has become the active system. Similarly, the layout drawing unit 31 continues the layout and drawing of the data broadcast screen according to the result of the first document analysis unit paired with the first layout drawing unit which was the active system. That is, the execution of the internal command is continued without accepting the external command, and the data broadcast screen is drawn. On the other hand, the second document analysis unit and the second layout drawing unit switched to the active system sequentially present the zapping channels including the data broadcast as usual.

  When the zapping is completed, the receiver control unit is notified of the end of the zapping, and the receiver control unit instructs the receiving unit and the demultiplexing unit to select the channel immediately before the zapping is started, and data broadcasting. Instructs the browser control unit of the browser to cancel the zapping state. Under control of the browser control browser, the first document analysis unit and the first layout drawing unit in the standby system are switched to the active system, and the second document analysis unit and the second layout drawing unit are switched to the standby system. . As a result, the first document analysis unit switched to the active system continues execution of the internal command and resumes execution of the external command for the temporary storage function of the data broadcast document. The first layout drawing unit switched to the active system performs the layout and drawing of the data broadcast screen in response to an instruction from the first document analysis unit. As a result, the data broadcast screen immediately before zapping is displayed in layout, video layout information is sent to the video reduction layout unit, and finally the data broadcast screen and TV video are synthesized and output from the video synthesis unit. In this way, it is possible to return to the channel at the time of starting zapping and continue to view the content of the original data broadcast screen.

  In addition, when zapping is newly started without returning to the original data broadcasting screen, the first document analysis unit and the layout drawing unit and the second document analysis unit and the layout drawing unit are alternately saved, and the other Data broadcasting is displayed using the document analysis unit and the layout drawing unit.

  In the second embodiment shown in FIG. 2, the actual layout and drawing must be performed by the layout drawing unit after the end of zapping is instructed. On the other hand, in this example, the layout drawing unit is saved while performing the layout and drawing, so that the data broadcast screen can be displayed immediately after the return. Accordingly, it is possible to further reduce the time required for returning to the original data broadcast screen after the completion of zapping.

When returning to the data broadcasting screen immediately before zapping, the newly decoded document is compared with the document before the channel switching, and when the version is changed or the document structure is different, the first and second This is the same as the second embodiment.

  FIG. 4 is a diagram showing a fourth embodiment of the digital broadcast receiver according to the present invention. In this example, a receiving unit 41, a demodulating unit 42, a demultiplexing unit 43, a data decoding unit 44, and a document analyzing unit 45 are provided in a plurality of systems (two systems in this example), and the state of the original channel is changed even during zapping. Can respond.

  The receiving unit, demodulating unit, demultiplexing unit, data decoding unit, and document analyzing unit immediately before zapping are set as system 1, system 1 is set as the active system, the system after zapping is set as system 2, and system 2 is set as the standby system. When zapping is detected or a zapping signal is input, the working system is saved and switched to the standby system. Then, the system 2 is switched to the active system, and the system 2 is used to receive the channel being zapped. Here, the term “save” means that the reception and demodulation operations are continued as they are in accordance with the input from the TV signal after being separated from the data broadcasting operation. When zapping is completed, the active system and the standby system are switched, the system immediately before zapping is returned to the active system, and data broadcasting immediately before zapping is resumed.

  In the present embodiment, even if the data broadcasting state changes during zapping, it is possible to completely follow. That is, in the first to third embodiments, when the data broadcast state changes during zapping, the continuation of data broadcast reception may not be guaranteed. In many cases, it is possible to continue receiving data broadcasts, but there are also cases where it is impossible to continue. On the other hand, in this example, since data broadcasting reception is always operated even during zapping, it can cope with any change in the state of data broadcasting as in the case of reception by a normal receiver. It becomes possible. As in the third embodiment, it is possible to shorten the return time to the original data broadcast screen by providing two layout drawing units.

In the first to third embodiments, since the data broadcast of the original channel is not always received during zapping, if the state of the data broadcast changes during zapping, it may not be restored correctly when returning. is assumed. Therefore, when a change in the state of the data broadcast is detected and it is determined that the normal return is impossible, it is necessary to give up the return and execute the data broadcast from the initial state. The exception handling in such a case is illustrated below.
(1) As a highly secure method, the data broadcast displayed at the start of zapping is updated from the initial state if there is an update, and if there is no update, the data broadcast is returned and continuously executed. As a method for detecting whether or not the data broadcast has been updated, a method for detecting a change in module version in the DSM-CC data carousel transmission method, which is a data broadcast transmission method, can be used.
(2) As a practical method, for a data broadcast displayed at the start of zapping, a method of returning to the original data broadcast and continuing execution when the BML document is not updated is assumed. When the BML document is updated, data broadcasting is executed from the initial state. In the case of this example, unlike (1) above, data broadcasting is continuously executed without setting the initial state only by changing the image (PNG, etc.) and data (binary table, etc.). Of course, the image and data are executed with the updated new data. The detection of the update of the BML document can be performed by the same method as the above (1) when one module is constituted by the BML document alone. However, in reality, one module is often composed of multiple files in addition to BML documents, so compare BML documents themselves or create and store message digests of BML documents for comparison. This method is effective.
(3) As the easiest method, it is assumed that the data broadcasting is resumed for the time being and the execution is continued as long as there is no contradiction. Conversely, when a contradiction occurs, the data broadcast is immediately initialized, or after sending a confirmation message, the data broadcast is initialized (presented in the initial state), or the data broadcast is terminated.

  In addition to changes in the state of data broadcasting, changes in internal state such as timer events considered in the first to fourth embodiments, and updating of data broadcasting documents or data considered in (1) to (3) above The state change by the event message can be used. A state change caused by an event message cannot be dealt with unless a receiving unit, a demodulating unit, a demultiplexing unit, and a data decoding unit are set up in a plurality of lines and a data broadcasting is always in a receiving state as in the fourth embodiment. Therefore, in order to cope with a state change caused by an event message, it is desirable to include the logic (3) as an exception process.

  Next, specific examples of control in Examples 2 to 4 having two systems (system 1 and system 2) as document analysis means will be described. FIG. 5 (1) shows control when a normal zapping operation is performed in a digital broadcast receiver having two systems. It is assumed that the program (chA) is viewed using the system 1 as the active system. When zapping is instructed and the channel is switched, the working system 1 is switched to the standby system, and the standby system 2 is switched to the working system. In this state, a new channel (chB) is presented. During zapping, the system 1 is kept in the retracted state, and the channels are switched in the system 2 to present new channels (chC, chD, chE). When the end of zapping is instructed, the saved system 1 is returned to the active system, and the original channel (chA) is presented again. Note that the system 1 and the system 2 are equivalent and can be established even if they are reversed.

(2) of FIG. 5 shows control when a new zapping is started in the middle of zapping. First, it is assumed that the program (chA) is viewed using the system 1. When the start of zapping is instructed and the channel is switched, the working system 1 is switched to the standby system, and the standby system 2 is switched to the working system. Then, a new channel (chB) is presented using the system 2. During zapping, channel 1 is switched in system 2 while system 1 is saved, and new channels (chC, chD, chE) are displayed. Here, it is assumed that the user likes a new channel (chE) and wants to make that channel a candidate, but continues zapping to check whether there is a more favorite channel. In this case, when the zapping is newly started and the channel is switched, the system 2 which is the active system is switched to the standby system, and the system 1 which is the standby system is switched to the active system. Then, a new channel (chF) is presented using the system 1. During the zapping, the channel 2 is switched in the system 1 while the system 2 is saved in the standby system, and new channels (chG, chH, chI) are presented. When the zapping is completed, the saved system 2 is restored and the display returns to the original channel (chE) display. Note that the system 1 and the system 2 are equivalent, and are the same even if they are set in reverse.

(3) of FIG. 5 is a diagram for explaining control when switching channels normally without zapping when two document analysis units are provided. In this example, it is assumed that two systems (system 1 and system 2) are used, and channel A is first viewed using system 1. Channel switching (chA → chB) and system switching (system 1 → 2) are performed at the same time. Next, when switching the channel from chA to chB, only the system is switched. Thus, when switching to the previous channel, the channel can be switched by simply switching the system. In this case, of course, the data broadcasting can be restored. Furthermore, as shown in (3) in FIG. 5, as long as to switch between the two channels, similar state is maintained. However, when switching to the third other channel (chB → chC), since the channel is switched, it is not possible to return to data broadcasting. However, as long as the two new channels are moved back and forth (chC → chB), there is no need to switch channels, and it is only necessary to restore the system, so that it is possible to restore the state to data broadcasting. When switching channels according to normal operation, it is possible to switch channels using only one system, but control as in this example enables continuity of data broadcasting and faster access. Become.

It is a diagram which shows the basic composition of the digital broadcast receiver by this invention. It is a diagram which shows 2nd Example of the digital broadcast receiver by this invention. It is a diagram which shows 3rd Example of the digital broadcast receiver by this invention. FIG. 7 is a diagram showing a fourth embodiment of a digital broadcast receiver according to the present invention. It is a diagram for demonstrating control in the case of having a plurality of document analysis units.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1,41 Receiving part 2,42 Demodulation part 3,43 Demultiplexing part 4 Audio decoding part 5 Video decoding part 6 Data decoding part 7 Video reduction layout part 8 Video composition part 9 Data broadcast browser 10 Receiver control part 11, 20, 30 Document analysis unit 12, 31 Layout drawing unit 13 Browser control unit

Claims (6)

Receiving means for receiving a channel selection signal and selecting a TV signal of a designated channel;
Demodulating means for demodulating the TV signal of the selected channel and outputting a digital signal stream;
Demultiplexing means for outputting an audio signal stream, a video signal stream, and a data signal stream, respectively, and a data decoding means for decoding the data signal stream and outputting a data broadcast document from the digital signal stream;
A data broadcast browser for receiving the data broadcast document and forming a data broadcast screen;
In a digital broadcast receiver comprising control means for controlling the above means,
The data broadcast browser receives the data broadcast document and outputs a layout information for forming a data broadcast screen, a layout analysis unit that receives the layout information and forms a data broadcast screen, and a document analysis Browser control means for controlling the means and layout drawing means,
When a channel switching signal is input during viewing of data broadcasting content, the browser control means instructs the document analysis means to hold a state and instructs the layout drawing unit to initialize,
When returning to the channel at the time when the channel switching signal is input, the browser control means instructs the document analysis means to cancel the state holding and instructs the layout drawing means to validate. Digital broadcast receiver. Receiving means for receiving a channel selection signal and selecting a TV signal of a designated channel;
Demodulating means for demodulating the TV signal of the selected channel and outputting a digital signal stream;
Demultiplexing means for outputting an audio signal stream, a video signal stream, and a data signal stream, respectively, and a data decoding means for decoding the data signal stream and outputting a data broadcast document from the digital signal stream;
A data broadcast browser for receiving the data broadcast document and forming a data broadcast screen;
In a digital broadcast receiver comprising control means for controlling the above means,
The data broadcast browser receives the data broadcast document and outputs a layout information for forming a data broadcast screen, a layout analysis unit that receives the layout information and forms a data broadcast screen, and a document analysis Browser control means for controlling the means and layout drawing means,
When a signal for instructing zapping is input during viewing of the data broadcasting content, the control means instructs the receiving means to sequentially switch channels, and the browser control means instructs the document analysis means. Instructing the state drawing to the layout and instructing the layout drawing unit to initialize,
When a signal for instructing the end of zapping is input, the control means instructs the receiving means to switch to the channel immediately before zapping, and the browser control means instructs the document analysis means to maintain the state. A digital broadcast receiver characterized by instructing release and instructing the layout drawing means to validate. Receiving means for receiving a channel selection signal and selecting a TV signal of a designated channel;
Demodulating means for demodulating the TV signal of the selected channel and outputting a digital signal stream;
Demultiplexing means for outputting an audio signal stream, a video signal stream, and a data signal stream, respectively, and a data decoding means for decoding the data signal stream and outputting a data broadcast document from the digital signal stream;
A data broadcast browser for receiving the data broadcast document and forming a data broadcast screen;
In a digital broadcast receiver comprising control means for controlling the above means,
The data broadcast browser receives the data broadcast document and outputs a layout information for forming a data broadcast screen, a layout analysis unit that receives the layout information and forms a data broadcast screen, and a document analysis Browser control means for controlling the means and layout drawing means,
The document analysis means includes first and second document analysis units that switch between the active system and the standby system,
When zapping is detected or a signal instructing zapping is input, the browser control means instructs the first document analysis unit of the active system to hold the state and switches from the active system to the standby system. Switch the second document analysis unit to the active system,
When the end of zapping is detected, the browser control means switches the active second document analysis unit to the standby system and switches the standby first document analysis unit to the active system. Broadcast receiver. The digital broadcast receiver according to claim 3, wherein the layout drawing means further includes first and second layout drawing units that switch between the active system and the standby system,
When zapping is detected or a signal instructing zapping is input, the browser control means instructs the first document analysis unit of the active system to hold the state, and the first document analysis unit and the first document analysis unit The layout drawing unit is switched to the standby system, the standby second document analysis unit and the second layout drawing unit are switched to the active system,
When the end or cancellation of zapping is detected, the browser control means switches the active second document analysis unit and the second layout drawing unit to the standby system, and sets the standby first document analysis unit and the second document analysis unit. A digital broadcast receiver characterized in that one layout drawing unit is switched to an active system. Receiving means for receiving a channel selection signal and selecting a TV signal of a designated channel;
Demodulating means for demodulating the TV signal of the selected channel and outputting a digital signal stream;
Demultiplexing means for outputting an audio signal stream, a video signal stream, and a data signal stream, respectively, and a data decoding means for decoding the data signal stream and outputting a data broadcast document from the digital signal stream;
A data broadcast browser for receiving the data broadcast document and forming a data broadcast screen;
Control means for controlling each of the above means,
The data broadcast browser receives the data broadcast document and outputs a layout information for forming a data broadcast screen, a layout analysis unit that receives the layout information and forms a data broadcast screen, and a document analysis In a digital broadcast receiver having browser control means for controlling the means and layout drawing means,
The receiving means, demodulating means, demultiplexing means, data decoding means, and document analysis means each have first and second systems that are alternately switched between the active system and the standby system,
When zapping is detected or a signal instructing zapping is input, the control means instructs the first system means of the active system to hold the state and switches the first system means to the standby system. , Switch the second system of the standby system to the active system,
A digital broadcast receiver characterized in that, when the end of zapping is detected, each of the second system means is switched to a standby system, and the first system means is switched to an active system.   The digital broadcast receiver according to any one of claims 1 to 5, further comprising means for detecting a state change of the data broadcast, wherein the data broadcast at the start of zapping and the data broadcast at the end of zapping A digital broadcast receiver characterized in that if a change in state is detected and if no change in state is recognized, the data broadcasting is resumed when zapping is disclosed, and if a change in state is recognized, the data broadcast is executed from the initial state. .