JP3921450B2 - Digital broadcast receiver, digital broadcast receiving method, and digital broadcast receiving program - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a digital broadcast receiver, a digital broadcast receiving method, and a digital broadcast receiving program for receiving a digital broadcast such as DAB (Digital Audio Broadcasting), and more specifically, a service content can be reproduced with a delay. The present invention relates to a digital broadcast receiver, a digital broadcast reception method, and a digital broadcast reception program.
[0002]
[Prior art]
Patent Document 1 discloses that digital audio broadcast content is stored, and when the user wants to hear the digital audio broadcast content from a predetermined time before the current time, the stored digital audio broadcast content is output in a delayed manner. To do.
[0003]
[Patent Document 1]
Japanese Patent No. 3135514
[0004]
[Problems to be solved by the invention]
Japanese Patent Application Laid-Open No. 2004-228561 does not explain any cancellation of delay output of a digital broadcast receiver. Since it is difficult to accept the user's further delay output instruction during the delay output, it is necessary to return the output of the digital broadcast content to the real time output before the user's next delay output instruction. . In addition, since the memory capacity for storing digital audio broadcast contents is limited, if unnecessary storage in the memory is not deleted, it becomes difficult to store the digital audio broadcast contents being received in the memory, and delay output is maintained. Can not do it. On the other hand, eliminating the delay output by an explicit user operation is inefficient particularly in a digital audio broadcast receiver mounted on a car. In addition, even when there is no explicit user operation, when the delayed output is automatically canceled, the automatic cancellation time may be inconvenient for the user.
[0005]
An object of the present invention is to provide a digital broadcast receiver capable of delay output of service contents without causing the user to perform an explicit operation for canceling the delay time and without causing inconvenience to the user. A broadcast receiver, a digital broadcast receiving method, and a digital broadcast receiving program are provided.
[0006]
[Means for Solving the Problems]
The digital broadcast receiver of the present invention has the following.
Storage means for storing service contents included in digital broadcasting.
Delay output means capable of performing delayed output by reading out and reproducing the service content stored in the storage means and outputting the service content delayed from the reception time.
Attribute content detection means for detecting the attribute content of the service content during delayed output.
Real-time output means capable of performing real-time output for outputting the service contents of the currently selected service in real time.
Effective output selection means for selecting one of delayed output and real-time output as an effective output.
・ Delay in which the delay time of delayed output is reduced or the effective output selection means switches the effective output from the delayed output to the real time output when the attribute content of the service content in the delayed output changes during the delayed output period Time control means.
[0007]
Another digital broadcast receiver of the present invention has the following.
Storage means for storing service contents included in digital broadcasting.
Delay output means capable of performing delayed output by reading out and reproducing the service content stored in the storage means and outputting the service content delayed from the reception time.
Real-time output means capable of performing real-time output for outputting the service contents of the currently selected service in real time.
Effective output selection means for selecting one of delayed output and real-time output as an effective output.
Service switching detection means for detecting that the user has switched the selected service.
Delay time control means for causing the effective output selection means to switch the effective output from the delay output to the real time output when the user switches the selection service during the delay output period.
[0008]
The digital broadcast receiving method of the present invention has the following steps.
A storage step of storing the service content included in the digital broadcast in the storage means.
A delay output step of performing a delay output in which the service content stored in the storage means is read out and played to delay and output the service content from the reception time;
An attribute content detection step for detecting the attribute content of the service content being delayed. A delay time control step of reducing the delay time of the delay output or switching the currently selected service from the delay output to the real time output for outputting in real time when the attribute content of the service content being delayed output is changed.
[0009]
Another digital broadcast receiving method of the present invention includes the following steps.
A storage step of storing the service content included in the digital broadcast in the storage means.
A delay output step of performing a delay output in which the service content stored in the storage means is read out and played to delay and output the service content from the reception time;
A service switching detection step for detecting that the user has switched the selected service.
An output switching step of switching from the delayed output to the real time output for outputting the currently selected service in real time when the user switches the selected service during the delay output period.
[0010]
The digital broadcast receiving program of the present invention causes a computer to execute each step in the digital broadcast receiving method.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 is a functional block diagram of the digital broadcast receiver 10. The storage unit 11 stores service contents included in digital broadcasting. The delay output means 12 reads out the service content stored in the storage means 11 and reproduces it, thereby enabling delay output to output the service content with a delay from the reception time. The attribute content detection unit 13 detects the attribute content of the service content output by the delay output unit 12. The real-time output means 14 can perform real-time output that outputs the service contents of the currently selected service in real time. The effective output selection means 15 makes one output of the delay output means 12 and the real time output means 14 effective. The delay time control means 16 reduces the delay time of the delay output or changes the effective output from the delay output to the real time when the attribute contents of the service contents in the delay output change during the delay output period. Do you want to switch to output?
[0012]
Digital broadcasting is not limited to digital audio broadcasting, and includes digital television broadcasting. The storage means 11 is an IC memory, DVD-RAM, MD, hardware, or a device. For example, the storage unit 11 can write new data while reproducing the data. Optical discs such as DVD-RAM and MD are either read or written at each point in time, but if they can be read and written at double speed, a new service for reproducing the service content at single speed and receiving it at single speed Content can be written. A typical digital broadcast includes multiple services. A plurality of storage means 11 are provided, and each service in the common ensemble can be simultaneously stored in each storage means 11. The delay time control unit 16 causes the effective output selection unit 16 to switch the effective output from the delay output to the real time output, which means that the delay time is set to zero. The delay time control means 16 reduces the delay time by a predetermined amount related to or independent of the attribute contents each time the attribute contents of the service contents being output from the delay output means 12 change without setting the delay time to 0 at once. As a result, the delay time can be reduced to zero in stages.
[0013]
The digital broadcast receiver includes a digital audio broadcast receiver, and the digital audio broadcast receiver includes a digital audio broadcast receiver mounted on an automobile. In the digital audio broadcast receiver, the audio service is stored in the storage unit 11 based on, for example, the MP3 standard.
[0014]
The user of the digital broadcast receiver 10 automatically performs the actual operation according to the change of the attribute content of the service content during the delay output without performing an explicit operation to switch the service from the delay output to the real time output. Since the time output is changed, the operability of the digital broadcast receiver 10 is improved. When the user next desires delayed output, the digital broadcast receiver 10 has already been output in real time, so that delayed output can be performed smoothly.
[0015]
FIG. 2 is obtained by adding functions to the digital broadcast receiver 10 of FIG. Only differences from FIG. 1 will be described. The management unit 20 manages user settings regarding whether or not the delay time of the delay output can be reduced when the attribute content of the service content being delayed is changed during the delay output period. The delay time control means 16 reduces the delay time or switches the effective output from the delay output to the real time output only when the user setting is permitted.
[0016]
As a result, in the digital broadcast receiver 10 of FIG. 2, when the user is set to prohibit the delay time decrease, even if the attribute content of the service content being delayed output changes during the delay output period, the delay time Is not changed.
[0017]
Typically, the service is an audio service, and the attribute of the service content includes, for example, the genre, song title, artist name, and / or track number in which the service content is stored in the storage unit 11. Is included. The attribute content means the content of each attribute. When the attribute is a song name, the attribute content is, for example, song name A, song name B,... In the case of an artist name, the attribute content is, for example, artist U, artist V, artist W,.
[0018]
In DAB, attribute information such as the song name and artist name is transmitted along with the audio itself in the audio service, and in MP3, the attribute information of the audio content is stored as tag information in association with the audio content itself. ing.
[0019]
When the valid output selecting means 15 switches the valid output from the delayed output to the real time output, the deleting means 21 has a service content having the same attribute content as the attribute content of the service content that was delayed before switching. Is deleted from the storage unit 11.
[0020]
The deletion by the deletion unit 21 and the deletion unit 32 (FIG. 3) described later includes not only deleting the deletion target portion in the storage unit 11 but also putting the storage area of the deletion target portion in an overwrite-permitted state. Due to the deletion, the current storage capacity in the storage unit 11 increases.
[0021]
FIG. 3 is a functional block diagram of another digital broadcast receiver 30. Among the elements of the digital broadcast receiver 30, the same elements as those of the digital broadcast receiver 10 described above are designated by the same reference numerals. The storage unit 11 stores service contents included in digital broadcasting. The delay output means 12 reads out the service content stored in the storage means 11 and reproduces it, thereby enabling delay output to output the service content with a delay from the reception time. The real-time output means 14 can perform real-time output that outputs the service contents of the currently selected service in real time. The effective output selection means 15 selects one of the delayed output and the real time output as an effective output. The service switching detection means 31 detects that the user has switched the selected service. The delay time control means 16 switches the effective output from the delay output to the real time output in the effective output selection means 15 when the user switches the selection service during the period when the output from the delay output means 12 is valid. Let
[0022]
Switching of the selection service by the user is performed, for example, when the user presses an operation button of the digital broadcast receiver 30. Switching of the selection service by the user during the delayed output of the digital broadcast receiver 30 is inconvenient to the user even if the delay time is eliminated because the user does not expect delayed output for the selected service after switching. There is almost no.
[0023]
The digital broadcast receiver 30 can be equipped with a deleting unit 32 as appropriate. Similarly to the deleting unit 21 in FIG. 2, when the delay time control unit 16 switches the effective output from the delayed output to the real time output, the deleting unit 32 outputs a delay before switching. All the service contents related to the service are deleted from the storage means 11.
[0024]
FIG. 4 is a flowchart of the digital broadcast receiving method. In storage step S36, the service contents included in the digital broadcast are stored in the storage means. In the delay output step S37, the service contents stored in the storage means are read out and reproduced, so that delayed output is performed by delaying and outputting the service contents from the reception time. In attribute content detection step S38, the attribute content of the service content being delayed is detected. In S38, it is determined whether or not the attribute content of the service content being delayed is changed. If the determination is “correct”, the process proceeds to the delay time control step S40. If the determination is “No”, The method ends. In S40, the delay time of the delay output is reduced or the currently selected service is switched from the delay output to the real time output for outputting in real time. Note that switching the delay output to the real-time output means setting the delay time to zero. In S41, it is determined whether or not the delay time is 0. If the determination is “positive”, the method is terminated. If the determination is “No”, the process returns to S38. The fact that the delay time is determined to be 0 in S41 means that in S40, (a) there has been a switch from the delay output to the real time output, or (b) the delay time has been reduced multiple times. Means 0 has been reached.
[0025]
FIG. 5 is a flowchart obtained by partially changing the flowchart of FIG. Bell only for the differences from the flowchart of FIG. In the management step S43, the user setting about whether or not the delay time of the delay output can be reduced when the attribute content of the service content during the delay output changes is managed, and the delay time control step only when the user setting is permitted The execution of S40 is permitted. That is, in S43, it is determined whether or not the user setting permits the change of the delay time. If the determination is “correct”, the process proceeds to S38. End the method. For example, the service is an audio service, and the attribute of the service content includes the genre of the service content, the song title, the artist name, and / or the track number in which the service content is stored in the storage unit 11. In addition, in the delay time control step S40b, in addition to the processing of the delay time control step S40 in FIG. 4, when the delay output is switched to the real time output, all the service contents related to the service that has been delayed output before the switching. Is deleted from the storage means 11.
[0026]
FIG. 6 is a flowchart of another digital broadcast receiving method. In the flowchart of FIG. 6, steps having the same processing contents as those in the flowchart of FIG. 4 are designated by the same reference numerals. In the storage step S36, the service content included in the digital broadcast is stored in the storage means 11. In the delay output step S37, the service contents stored in the storage means 11 are read out and reproduced, thereby delaying the service contents from the reception time and outputting them. In service switching detection step S45, as soon as it is detected that the user has switched the selected service, the process proceeds to output switching step S46. In S46, the currently selected service is switched from the delayed output to the real time output for outputting in real time.
[0027]
In S46, in addition to the above-described processing, all the service contents related to the service that was delayed before switching can be deleted from the storage unit 11.
[0028]
Further, a digital broadcast receiving program is prepared. The digital broadcast receiving program causes a computer to execute each step in the digital broadcast receiving method described with reference to FIGS.
[0029]
【Example】
FIG. 7 is a block diagram of a transmitter 50 for DAB (Digital Audio Broadcasting). The transmitter 50 transmits an ensemble of a plurality of audio services and a plurality of data services. The audio compression encoder 51 performs audio compression by the MPEG (moving image compression) audio system. The error correction encoder 52 performs error correction encoding on the audio compression encoded data by a convolution method. Similarly, the error correction encoder 55 performs error coding on the data service by a convolution method. The time interleavers 53 and 56 perform time interleaving on the data error-encoded by the error correction encoders 52 and 55. The multiplexer 54 multiplexes the data interleaved with the time interleavers 53 and 56. An orthogonal frequency division multiplex modulator (OFDM unit) 57 performs inverse fast Fourier transform (IFFT) on the multiplexed data. The high frequency device (RF device) 58 converts the frequency of the signal in the time domain subjected to the inverse fast Fourier transform into a transmission frequency by the oscillator 59.
[0030]
The main transmission parameters of DAB are as follows.
Number of symbols: 76.
Transmission bandwidth: 1,536 MHz.
Number of carriers: 1536.
Carrier frequency interval: 1 KHz.
Number of frames: 96 ms.
NULL symbol length: 1.297 ms.
Effective symbol length: 1 ms.
Guard interval period: 246 μs.
Use: SFN.
Use frequency band: 375 MHz or less.
Total transmission amount: 2.3 Mbit / sec.
[0031]
The audio broadcasting band in DAB band III is 174 to 240 MHz, and is composed of a plurality of ensembles having a transmission bandwidth of 1.5 MHz, and each ensemble includes a plurality of audio services and a plurality of data services. Strictly speaking, the ensemble includes a plurality of services, and each service includes one primary service component and zero or more secondary service components. The primal service component is an audio service, the secondary service component is a primary service component, and an audio service and a data service.
[0032]
FIG. 9 is a configuration diagram of a transmission frame formed by the multiplexer 54 of FIG. The transmission frame has a synchronization channel, FIC (Fast Information Channel), and MSC (Main Service Channel) in order from the front. The MSC is a channel for audio data transfer, and one symbol constituting this is composed of a guard interval and a valid symbol. The guard interval absorbs a delay within this time even when a delayed wave such as a multipath wave is received. Symbol data is obtained by modulating a large number of orthogonal subcarriers by a method such as quadrature phase modulation (QPSK) or 16 quadrature phase amplitude modulation (QAM).
[0033]
The OFDM unit 57 (FIG. 7) performs serial-parallel conversion on transmission data and then performs inverse discrete Fourier transform. The transmission wave thus generated has a transmission bandwidth of about 1.5 MHz and 1536 subcarriers (in the case of mode I).
[0034]
FIG. 8 is a configuration diagram of the DAB car radio 70. The received signal is down-converted by the high frequency unit 71 and the PLL circuit 72 and is orthogonally demodulated. Thereafter, the signal is converted from analog to digital, converted from a time domain to a frequency domain by a fast Fourier transformer (FFT unit) 73, and demodulated a subcarrier to extract data. The FFT unit 73 is composed of a digital signal processor (DSP). The time deinterleave / Viterbi decoder 74 performs time deinterleave on the time-interleaved data, and further Viterbi-decodes the data that has been error correction encoded by the convolution method. The audio compression decoder 75 decodes the audio compression encoded data and generates an audio signal for a predetermined audio service. Thereafter, the data is converted from digital to analog and output as audio from the speaker 77 via the amplifier 76.
[0035]
The output of the time deinterleave / Viterbi decoder 74 is sent to the data decoder 79 and decoded into the character code of the data service, and then the text as the information content of the data service is displayed on the display 80. The operation key 82 is provided in the peripheral portion of the display device 80 and is operated by the user. The microcomputer 81 receives a user instruction from the operation key 82 and information from the time deinterleave / Viterbi decoder 74 and sends a control signal to the PLL circuit 72 and the time deinterleave / Viterbi decoder 74 and the like in the RF unit 71. Selection of a high frequency for down conversion, selection of an output audio channel from the time deinterleave / Viterbi decoder 74, and the like are performed.
[0036]
The storage means 84 is composed of, for example, an IC memory, a DVD (digital video disk), a hard disk, or an MD (mini disk). The storage means 84 stores any output signal of the RF unit 71, the FFT unit 73, and the time deinterleave / Viterbi decoder 74. The storage means 84 can also return the stored signal to the output unit of the RF unit 71, the FFT unit 73, and the time deinterleave / Viterbi decoder 74 as a location for taking in the stored signal, that is, an FFT unit. 73, the time deinterleave / Viterbi decoder 74, and the audio compression decoder 75 can be supplied to the input unit. The user can listen to the audio service at a time delayed by a predetermined time with respect to the actual broadcast time by reproducing the data stored in the storage means 84. The storage means 84 captures and stores the output of the time deinterleave / Viterbi decoder 74, and when returning the reproduction signal to the output unit of the time deinterleave / Viterbi decoder 74, all or predetermined values included in the selected ensemble are stored. In order to store the audio signals of a plurality of audio services, a plurality of storage means 84 may be provided. In response to a delay output instruction from the user via the operation key 82, the microcomputer 81 reads data from the storage means 84 and outputs the corresponding service content from the speaker 77, that is, delays by a predetermined time from the actual reception time. The delayed output is performed.
[0037]
FIG. 10 is a structural diagram of the MP3ID3v1.1 tag. The storage means 84 stores the service in, for example, an MP3ID3v1.1 tag format. In this storage format, in addition to the MP3 audio unit that stores the service content itself, a TAG name as an attribute of the service content in association with the service content, The song name, artist name, album name, production year, comment, track number, and music genre are written.
[0038]
FIG. 11 is a conceptual diagram of delay time control. In the real time output, the currently selected service is output from an audio output means such as a speaker at the real time, that is, the reception time. On the other hand, the delayed output is stored in the storage means 84 for the currently selected service and within a predetermined time T1 (T1 is related to the storage capacity of the storage means 11) from the reception time. The service contents from before T2 ≦ T1) are output from the audio output means with a delay from the real time by reading out the data related thereto from the storage means 84 and reproducing it. In an audio service, it is assumed that song A, song B, song C, song D,... Are broadcast continuously. A, B, C, D,... Mean music titles. The song name is assumed to be the attribute content of the service content, and it is assumed that the user has previously set permission to cancel the delay time for the attribute content. In FIG. 11, a thick black horizontal line indicates which of the real-time output and the delayed output is valid. The thick black horizontal line on the upper side means that real-time output is performed, and the thick black horizontal line on the lower side means that delay time output is performed. While listening to the song A with real time output, the user wants to hear the song A from the beginning, and at time t, instructs the delay output from a predetermined operation key of the digital audio broadcast receiver. In this case, the delayed output is delayed by a time T2 with respect to the real time. In the delayed output, when the song A ends, the song name as the attribute content in the delayed output changes, so that the valid output is automatically switched from the delayed output to the real time output, and the delay time is eliminated. Further, along with this switching, the data of song A is deleted from the delay output memory, and the remaining storable amount of the memory increases.
[0039]
In FIG. 11, the description has been given by taking the name of a song as an example, but the same applies when an artist name, a genre, a track number, or the like is selected as an attribute. In other words, as the artist name or genre changes for delayed service contents, switching from delayed output to real-time output, or a gradual decrease in delay time, or delayed output before switching Data of the service content of the artist name or genre that is the same as the artist name or genre of the service content that has been stored is deleted from the storage means.
[0040]
【The invention's effect】
According to the present invention, in a digital broadcasting receiver capable of delay output of service contents, without requiring an explicit operation for canceling the delay time during delay output, and without inconvenience to the user, Real-time output delay time can be eliminated automatically.
[Brief description of the drawings]
FIG. 1 is a functional block diagram of a digital broadcast receiver.
FIG. 2 is obtained by adding a function to the digital broadcast receiver of FIG.
FIG. 3 is a functional block diagram of another digital broadcast receiver.
FIG. 4 is a flowchart of a digital broadcast receiving method.
5 is a flowchart obtained by partially changing the flowchart of FIG.
FIG. 6 is a flowchart of another digital broadcast receiving method.
FIG. 7 is a configuration diagram of a DAB transmitter.
FIG. 8 is a configuration diagram of a car radio for DAB.
9 is a configuration diagram of a transmission frame formed by the multiplexer of FIG. 7. FIG.
FIG. 10 is a structural diagram of an MP3ID3v1.1 tag.
FIG. 11 is a conceptual diagram of delay time control.
[Explanation of symbols]
10 Digital broadcast receiver
11 Storage means
12 Delay output means
13 Attribute content detection means
14 Real-time output means
15 Effective output selection means
16 Delay time control means
20 Management means
21 Deletion means
30 Digital broadcast receiver
31 Service switching detection means
32 Deletion means

Claims (13)

Storage means for storing service contents included in digital broadcasting;
Delay output means capable of implementing delayed output for outputting the service contents delayed from the reception time by reading and reproducing the service contents stored in the storage means,
Attribute content detection means for detecting attribute content of service content during delayed output,
Real-time output means that can perform real-time output that outputs the service contents of the currently selected service in real time,
Effective output selection means for selecting one of the delay output and the real time output as an effective output, and whether the delay time of the delay output is reduced when the attribute content of the service content in the delay output changes during the delay output period. Delay time control means for enabling the effective output selection means to switch the effective output from the delay output to the real time output;
A digital broadcast receiver characterized by comprising: A management means for managing user settings as to whether or not the delay time of the delay output can be reduced when the attribute content of the service content during the delay output changes during the delay output period;
Have
2. The digital broadcast receiver according to claim 1, wherein the delay time control means reduces the delay time or switches the effective output from the delay output to the real time output only when the user setting is permitted. The service is an audio service, and the service content attribute includes a genre of the service content, a song title, an artist name, and / or a track number in which the service content is stored in the storage unit. The digital broadcast receiver according to claim 1 or 2. When the valid output selecting means switches the valid output from the delay output to the real time output, the storage related to the service content having the same attribute content as the service content attribute content that was delayed before the switching is stored in the memory Deletion means for deleting from the storage means;
The digital broadcast receiver according to claim 1, wherein the digital broadcast receiver is provided. Storage means for storing service contents included in digital broadcasting;
Delay output means capable of implementing delayed output for outputting the service contents delayed from the reception time by reading and reproducing the service contents stored in the storage means,
Real-time output means that can perform real-time output that outputs the service contents of the currently selected service in real time,
Effective output selection means for selecting one of the delay output and the real time output as an effective output;
Service switching detecting means for detecting that the user has switched the selected service, and a delay for causing the effective output selecting means to switch the effective output from the delayed output to the real time output when the user switches the selected service during the delay output period. A digital broadcast receiver comprising time control means. When the delay time control means causes the effective output selection means to switch the effective output from the delay output to the real time output, the entire service contents related to the service that was delayed before switching are deleted from the storage means. Delete means,
6. The digital broadcast receiver according to claim 5, further comprising: A storage step of storing the service contents included in the digital broadcast in a storage means;
A delay output step of performing a delay output that reads out and reproduces the service content stored in the storage means and outputs the service content with a delay from the reception time;
Attribute content detection step that detects the attribute content of the service content being delayed, and when the attribute content of the service content being delayed is changed, the delay time of the delayed output is reduced or the currently selected service is real time Delay time control step to switch from delay output to real time output output at
A digital broadcast receiving method characterized by comprising: When the attribute contents of the service contents during delay output change, the user setting about whether or not the delay time of the delay output can be reduced is managed, and the execution of the delay time control step is allowed only when the user setting is permitted. 8. The digital broadcast receiving method according to claim 7, further comprising a management step. The service is an audio service, and the service content attribute includes a genre of the service content, a song title, an artist name, and / or a track number in which the service content is stored in the storage unit. The digital broadcast receiving method according to claim 7 or 8. The delay time control step of deleting the storage related to the service content having the same attribute content as the service content attribute output delayed before switching from the storage means when switching from the delay output to the real time output ,
The digital broadcast receiving method according to claim 7, wherein the digital broadcast receiving method is provided. A storage step of storing the service contents included in the digital broadcast in a storage means;
A delay output step of performing a delay output that reads out and reproduces the service content stored in the storage means and outputs the service content with a delay from the reception time;
Service switching detection step for detecting that the user has switched the selected service, and when the user switches the selected service during the delay output period, from the delayed output to the real time output that outputs the currently selected service in real time Output switching step for switching,
A digital broadcast receiving method characterized by comprising: In the case of switching from delayed output to real-time output, the output switching step of deleting all the service contents related to the service that was delayed before switching from the storage means,
The digital broadcast receiving method according to claim 11, further comprising: 13. A program for receiving digital broadcasts, which causes a computer to execute each step in the digital broadcast receiving method according to claim 7.

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