JP2008311861A - Broadcast receiving device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a broadcast receiving device for reducing the sense of incongruity that a viewer feels when currently received segments are changed. <P>SOLUTION: An MPU 116 monitors a decoder error rate detected by a decoder 108 minute by minute, and when the decoder error rate rises more than a preset level and when the MPU 116 detects that a receiving state has deteriorated, the MPU 116 first controls a selecting part 107 so as to change data having the higher error rate out of decoder error rates (error rate of audio data and error rate of video data) to stream data of a hierarchy having a strong error resistance. Then, the MPU 116 controls the selecting part 107 so as to change the other remaining data to steam data of the already changed hierarchy having a strong error resistance after the elapse of the preset period of time. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a broadcast receiving apparatus used to receive a broadcast such as a terrestrial digital broadcast.

  As is well known, terrestrial digital broadcasting has started, and reception environments are being prepared throughout the country. In general digital broadcasting, such as terrestrial digital broadcasting, the same content is broadcast in a plurality of segments (bands), and the segment is switched according to the reception state to receive the broadcast, thereby enabling stable viewing (for example, Patent Document 1).

However, the conventional broadcast receiving apparatus has a problem that when the segment being received is switched to another segment, discontinuity occurs between the audio and the video, so that the viewer has a strong sense of incongruity when switching the segment.
JP2002-0944402

In the conventional broadcast receiving apparatus, when switching the segment being received to another segment, there is a discontinuity between the audio and the video, so that there is a problem that the viewer has a strong sense of incongruity when switching the segment.
The present invention has been made to solve the above problem, and an object of the present invention is to provide a broadcast receiving apparatus that reduces the uncomfortable feeling felt by the viewer when the segment being received is switched.

  In order to achieve the above object, the present invention is directed to receiving means for receiving radio signals each including first data and second data, and demodulating the radio signals received by the receiving means to obtain first data and first data Included in the channel data output from the separating means for separating the data into a plurality of channel data each including two data, the selecting means for selecting and outputting any one of the plurality of channel data, and the selecting means Decoding means for decoding the first data and the second data respectively, and an error included in the first data and the second data is detected at the time of decoding by the decoding means, and based on this, the data quality falls below a preset level A detecting means for detecting the deterioration, and the selecting means is controlled when the detecting means detects that the detecting means has deteriorated below the level. The first data included in the other channel data is output instead of the first data of the channel data that has been output, and the channel that has been selected and output by the selection means when a preset condition is satisfied after that. Control means for outputting second data of other channel data instead of the second data of data is provided.

  As described above, in the present invention, when the reception quality deteriorates, the first data and the second data are not switched to another channel (segment) at the same time, but the first data is switched first. After a certain time has elapsed, the remaining second data is switched.

  Therefore, according to the present invention, even when the channel is switched, the first data is switched first while continuing to reproduce the second data, and then the second data is also switched. One data can be continuously reproduced without interruption, and a broadcast receiving apparatus can be provided in which the discomfort felt by the viewer when the channel being received is switched is reduced.

Embodiments of the present invention will be described below with reference to the drawings.
FIG. 1 shows the configuration of a broadcast receiving apparatus according to an embodiment of the present invention. This broadcast receiving apparatus includes an antenna 101, a tuner 102, an OFDM demodulation unit 103, an error correction unit 104, a layer separation unit 105, a layer-specific error detection unit 106, a selection unit 107, a decoder 108, and a decoder. Error detection unit 109, BUS 110, audio controller 111, speaker 112, graphic controller 113, monitor 114, external interface (I / O) 115, MPU (Micro Processing Unit) 116, ROM 117, RAM 118 With.

  A digital broadcast radio signal transmitted from a transmitting station is received by a tuner 102 through an antenna 101, down-converted into a baseband signal, and then converted from an analog signal to a digital signal. This digital signal is OFDM (Orthogonal Frequency Division Multiplexing) modulated, and consists of 13 OFDM blocks to which pilot signals are added.

  The OFDM demodulator 103 demodulates the digital signal to obtain a transport stream packet (TSP) composed of 13 segments. This transport stream packet includes error detection information embedded in accordance with transmission data on the transmission side. In addition, the transport stream packet has a maximum of three layers, and the transmission characteristics differ from layer to layer. That is, the number of segments, modulation scheme, convolutional coding rate, etc. are set for each layer.

  The error correction unit 104 detects and corrects errors in the transport stream based on the error detection information in accordance with an instruction from the MPU 116 via the BUS 110. The transport stream whose error has been corrected here is output to the layer separation unit 105. The error correction unit 104 detects an error rate (hereinafter referred to as a stream error rate) based on the detected error, and records this in the RAM 118 through the BUS 110.

  The layer separation unit 105 separates the transport stream that has been error-corrected by the error correction unit 104 into streams a, b, and c for each layer, and outputs these to the layer-specific error detection unit 106 and the selection unit 107, respectively. .

  The layer-specific error detection unit 106 detects an error rate (hereinafter referred to as a layer-specific error rate) for each of the streams a, b, and c for each layer based on the error detection information included in each stream. This hierarchical error rate is recorded in the RAM 118 through the BUS 110 by the hierarchical error detection unit 106.

  The selection unit 107 selects any one of the streams a, b, and c output from the layer separation unit 105 in accordance with an instruction from the MPU 116 via the BUS 110 and outputs the selected stream to the decoder 108.

  The decoder 108 decodes the stream input from the selection unit 107 and corrects errors as necessary, and includes an audio decoder 108a and a video decoder 108b. Of the input streams, audio data is input to the audio decoder 108a, and video data is input to the video decoder 108b.

The audio decoder 108a decodes the input audio data, and if an error is detected during decoding, the audio decoder 108a corrects this error and notifies the decoder error detection unit 109 that an error has occurred.
Similarly, the video decoder 108b decodes input video data, and when an error is detected during decoding, the video decoder 108b corrects this error and notifies the decoder error detection unit 109 that an error has occurred.

  Further, the decoder 108 detects the level fluctuation of the audio data decoded by the audio decoder 108a, and changes the level of the luminance and color space information (RGB, YUV, etc.) of the video data decoded by the video decoder 108b. , And a correlation within a certain time of the audio data (hereinafter referred to as audio temporal correlation) and a correlation within the certain time of the video data (hereinafter referred to as video temporal correlation) are detected respectively. In general, continuous data within a short period of time has high continuity in its level, few steep fluctuations, and high temporal correlation.If data loss or error occurs, this temporal correlation is descend.

  The decoder 108 compares reference signals included in each of a plurality of continuous audio data decoded by the audio decoder 108a, detects a synchronization shift (hereinafter referred to as an audio synchronization error) in the audio data, and also detects video. Reference signals included in each of a plurality of continuous video data decoded by the decoder 108b are compared to detect a synchronization shift (hereinafter referred to as a video synchronization error) in the video data.

  Then, the decoder 108 synchronizes the decoded audio data and video data, and records these data in the RAM 118. The decoder 108 records the temporal correlation and the synchronization error of each data in the RAM 118.

  Based on the notification from the audio decoder 108a and the video decoder 108b, the decoder error detection unit 109 detects each error rate of the decoded audio data and video data of the stream output from the selection unit 107. Then, the decoder error detection unit 109 records each decoded error rate as a decoder error rate in the RAM 118 through the BUS 110.

  The audio controller 111 reads audio data decoded from the RAM 118 through the BUS 110 in accordance with an instruction from the MPU 116 and converts it into an analog audio signal. The analog audio signal is output through the speaker 112.

  The graphic controller 113 reads the video data decoded from the RAM 118 through the BUS 110 in accordance with an instruction from the MPU 116 and converts it into a video signal. This video signal is output as video through the monitor 114.

  Various devices are physically and electrically connected to the external interface (I / O) 115, and audio data and video data read from the RAM 118 under the control of the MPU 116 are transferred to the above devices via the I / O 115. Output.

The ROM 117 stores the control program and control data of the MPU 116 and is read out through the BUS 110.
The RAM 118 stores video data, audio data, various detection information and control parameters, and the above data is read and written through the BUS 110.

  The MPU 116 controls the respective units of the broadcast receiving apparatus in an integrated manner. The MPU 116 switches the selection unit 107 according to the decoder error rate detected by the decoder error detection unit 109 to obtain a desired reception quality. Are output to the subsequent decoder 108 for decoding.

  The MPU 116 also controls the selection unit 107 based on the stream error rate, the layer-specific error rate, the decoder error rate, the temporal correlation, and the synchronization error recorded in the RAM 118, and the audio data and video of the streams a, b, and c. Data is individually selected at an arbitrary timing, and is output to the subsequent decoder 108 for decoding. That is, the MPU 116 can switch, for example, one of audio data and video data to data of another stream that can be viewed stably without being linked to the other.

  Here, the operation according to the first embodiment of the broadcast receiving apparatus having the above configuration will be described first. The MPU 116 monitors the decoder error rate detected every moment by the decoder 108. When the MPU 116 detects that the decoder error rate has risen above a preset level and the reception state has deteriorated, first, the decoder error rate ( Of the audio data error rate and the video data error rate), the selection unit 107 is controlled so as to switch the data having the higher error rate to the data of the stream having the higher error tolerance. Then, after a preset time elapses, the selection unit 107 is controlled so that the remaining one of the data is switched to the data of the already switched error-resistant layer stream.

  As described above, in the broadcast receiving apparatus configured as described above, when the reception state deteriorates, both the audio data and the video data are not simultaneously switched to other stream data having a high error tolerance, but the error rate is improved. After a certain period of time has passed after switching the higher data first, the remaining data is switched.

  Therefore, according to the broadcast receiving apparatus having the above configuration, even when switching the hierarchy of the playback stream, the data with the lower error rate is switched first while switching the data with the higher error rate, while continuing the playback. Since the data with the lower error rate is also switched, at least one of the data can be continuously played back when the segment is switched, and the viewer's uncomfortable feeling when switching the segment can be reduced.

  In this embodiment, the data with the higher error rate is always switched first. However, the present invention is not limited to this, and preset data (eg, audio data) is always switched first. You may do it.

Next, the operation according to the second embodiment of the broadcast receiving apparatus having the above configuration will be described.
The MPU 116 monitors the audio synchronization error and the video synchronization error that are detected every moment by the decoder 108, and that any of these synchronization errors has risen to a predetermined level or more and the reception state has deteriorated. When detected, first, the selection unit 107 is controlled so as to switch the data whose synchronization error has risen to a preset level or higher to the data of the stream of the layer having strong error tolerance. Then, after a preset time elapses, the selection unit 107 is controlled so that the remaining one of the data is switched to the data of the already switched error-resistant layer stream.

  As described above, in the broadcast receiving apparatus configured as described above, when the reception state deteriorates, both the audio data and the video data are not simultaneously switched to the stream data of another layer having high error resistance, but the synchronization error is not generated. The larger data is switched first, and after a certain time has passed, the remaining data is switched.

  Therefore, according to the broadcast receiving apparatus having the above configuration, even when switching the hierarchy of the playback stream, the data with the smaller synchronization error is first switched while continuing to reproduce the data with the smaller synchronization error, Since the data with the smaller synchronization error is also switched, at least one of the data can be continuously played back at the time of segment switching, and the viewer's uncomfortable feeling at the time of segment switching can be reduced.

  In this embodiment, it has been described that the data with the larger synchronization error is always switched first. However, the present invention is not limited to this, and the preset data (for example, audio data) is always switched first. You may do it.

Next, an operation according to the third embodiment of the broadcast receiving apparatus having the above configuration will be described.
The MPU 116 monitors the audio temporal correlation and the video temporal correlation detected every moment by the decoder 108, and any of these temporal correlations falls below a preset level, and the reception state deteriorates. If it is detected, first, the selection unit 107 is controlled so as to switch the data whose temporal correlation has dropped below a preset level to the stream data having a higher error tolerance. Then, after a preset time elapses, the selection unit 107 is controlled so that the remaining one of the data is switched to the data of the already switched error-resistant layer stream.

  As described above, in the broadcast receiving apparatus having the above-described configuration, when the reception state deteriorates, both the audio data and the video data are not simultaneously switched to the other stream data having a high error resistance, but are temporally correlated. The data with the larger drop is switched first, and after a certain time has passed, the remaining data is switched.

  Therefore, according to the broadcast receiving apparatus having the above configuration, even when the hierarchy of the playback stream is switched, the data with the smaller temporal correlation is maintained while the data with the smaller temporal correlation is continuously reproduced. Since switching is performed first, and data having a smaller temporal correlation is also switched, at least one of the data can be continuously played back without interruption during segment switching, and the viewer's uncomfortable feeling during segment switching can be reduced.

  In this embodiment, it has been described that the data having the larger temporal correlation decrease is always switched first, but the present invention is not limited to this, and the preset data (eg, audio data) is always used. You may make it switch first.

Next, the operation according to the fourth embodiment of the broadcast receiving apparatus having the above configuration will be described.
The MPU 116 monitors the stream error rate detected from moment to moment by the error correction unit 104. When the MPU 116 detects that the reception state has deteriorated due to an increase in a level higher than a preset level, the MPU 116 first sets preset data (for example, audio The selection unit 107 is controlled so that the data of the data) is switched to the data of the stream with higher error tolerance. Then, after a preset time elapses, the selection unit 107 is controlled so that the remaining one of the data is switched to the data of the already switched error-resistant layer stream.

  As described above, in the broadcast receiving apparatus configured as described above, when the reception state deteriorates, both the audio data and the video data are not simultaneously switched to other stream data having a high error resistance, but one of the data Is switched first, and after a certain time has passed, the remaining data is switched.

  Therefore, according to the broadcast receiving apparatus having the above configuration, even when switching the hierarchy of the playback stream, while continuing to play back one data, the other data is switched first, and then the remaining data is also switched. In addition, at least one of the data can be continuously played back when the segment is switched, and the viewer's uncomfortable feeling when switching the segment can be reduced.

Finally, the operation according to the fifth embodiment of the broadcast receiving apparatus having the above configuration will be described.
The MPU 116 monitors the layer-specific error rate detected by the layer-specific error detection unit 106 every moment, and detects that the reception state has deteriorated because the layer-specific error rate of each layer has risen above a preset level. Then, first, the selection unit 107 is controlled so as to switch the preset data (for example, audio data) to the data of the stream having a higher error tolerance. Then, after a preset time elapses, the selection unit 107 is controlled so that the remaining one of the data is switched to the data of the already switched error-resistant layer stream.

  As described above, in the broadcast receiving apparatus configured as described above, when the reception state deteriorates, both the audio data and the video data are not simultaneously switched to other stream data having a high error resistance, but one of the data Is switched first, and after a certain time has passed, the remaining data is switched.

  Therefore, according to the broadcast receiving apparatus having the above configuration, even when switching the hierarchy of the playback stream, while continuing to play back one data, the other data is switched first, and then the remaining data is also switched. In addition, at least one of the data can be continuously played back when the segment is switched, and the viewer's uncomfortable feeling when switching the segment can be reduced.

In this embodiment, the error rate for each layer is monitored, but instead, for example, only the error rate for each layer of the layer selected by the selection unit 107 may be monitored. Good.
Further, in each of the above embodiments, after switching the data with the higher error rate, it is described that the switching of the other data is performed when a preset time has elapsed. Switching, when silence is detected for audio data, when a screen with low luminance is detected for video data, or when temporal correlation is low, that is, there is a discontinuity between screens due to noise or scene changes. It is also possible to use the time when it is detected.

  Note that the present invention is not limited to the above-described embodiment as it is, and can be embodied by modifying the constituent elements without departing from the scope of the invention in the implementation stage. In addition, various inventions can be formed by appropriately combining a plurality of constituent elements disclosed in the embodiment. Further, for example, a configuration in which some components are deleted from all the components shown in the embodiment is also conceivable. Furthermore, you may combine suitably the component described in different embodiment.

  For example, in the first to fifth embodiments, the deterioration of the reception state is detected based on a single indicator, but the deterioration of the reception state may be detected based on a plurality of indicators. For example, both the stream error rate detected by the error correction unit 104 and the decoder error rate detected by the decoder 108 are monitored, and when both of them rise and the reception state deteriorates, or at least one of them rises and is received When the state deteriorates, segment switching with a time difference as described above is performed.

  Further, when a plurality of indicators are monitored in this way, any of them may be preferentially used to determine that the reception state has deteriorated. For example, the stream error rate, decoder error rate, and synchronization error are monitored, and even if the stream error rate and decoder error rate are low, if the synchronization error that makes viewers feel uncomfortable is large, the reception state has deteriorated. judge.

  Further, in the above embodiment, as shown in FIG. 2, switching when the reception state deteriorates has been described, but conversely, when the reception state becomes favorable, the data of the stream of the layer having low error resistance is included. It is also possible to control the selection unit 107 to switch.

The circuit block diagram which shows the structure of one Embodiment of the broadcast receiver concerning this invention. The figure for demonstrating the segment switching of the broadcast receiver shown in FIG.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 101 ... Antenna, 102 ... Tuner, 103 ... OFDM demodulation part, 104 ... Error correction part, 105 ... Hierarchy separation part, 106 ... Error detection part according to hierarchy, 107 ... Selection part, 108a ... Audio decoder, 108b ... Video decoder, 109 Decoder error detection unit, 110 ... BUS, 111 ... Audio controller, 112 ... Speaker, 113 ... Graphic controller, 114 ... Monitor, 115 ... I / O, 116 ... MPU, 117 ... ROM, 118 ... RAM.

Claims (9)

Receiving means for receiving radio signals each including first data and second data;
A separating unit that demodulates the radio signal received by the receiving unit and separates the wireless signal into a plurality of channel data each including the first data and the second data;
Selecting means for selecting and outputting any one of the plurality of channel data;
Decoding means for respectively decoding the first data and the second data included in the channel data output by the selection means;
Detecting means for detecting an error included in the first data and the second data at the time of decoding by the decoding means, and detecting that the data quality has deteriorated below a preset level based on the error;
When the detecting means detects that the level has deteriorated below the level, the selecting means is controlled to replace the first data of the channel data already selected and output by the selecting means with other channel data. When the first data included is output, and then a preset condition is satisfied, the second data of the other channel data is substituted for the second data of the channel data selected and output by the selection means. A broadcast receiving apparatus comprising: control means for outputting Receiving means for receiving radio signals each including first data and second data;
Demultiplexing means for demodulating the radio signal received by the receiving means and separating the radio signal into a plurality of channel data each including first data and second data;
Selecting means for selecting and outputting any one of the plurality of channel data;
Decoding means for decoding the first data and the second data of the channel data output by the selection means,
The synchronization error of each data is detected based on the reference signal included in each of the first data and the second data decoded by the decoding means, and based on this, the data quality has deteriorated below a preset level. Detecting means for detecting;
When the detecting means detects that the level has deteriorated below the level, the selecting means is controlled and included in the other channel data in place of the first data of the channel that has already been selected and output by the selecting means. If the preset condition is satisfied after that, the second data of the other channel channel is replaced with the second data of the channel data selected and output by the selection means. A broadcast receiving apparatus comprising control means for outputting. Receiving means for receiving radio signals each including first data and second data;
Demodulation means for demodulating the radio signal received by the receiving means to obtain a data stream;
Error detection means for detecting errors contained in the data stream obtained by the demodulation means;
Separating means for separating the data stream into a plurality of channel data each including first data and second data;
Selecting means for selecting and outputting any one of the plurality of channel data;
Decoding means for respectively decoding the first data and the second data included in the channel data output by the selection means;
Detection means for detecting that the reception quality has deteriorated to a preset level or less based on the detection result of the error detection means;
When the detecting means detects that the level has deteriorated below the level, the selecting means is controlled to replace the first data included in the channel data already selected and output by the selecting means with another channel. When the first data included in the data is output and a preset condition is satisfied after that, the other channel data is substituted for the second data included in the channel data selected and output by the selection means. And a control means for outputting the second data included in the broadcast receiving apparatus. Receiving means for receiving radio signals each including first data and second data;
Demultiplexing means for demodulating the radio signal received by the receiving means and separating the radio signal into a plurality of channel data each including first data and second data;
Error detection means for detecting an error included in each of the plurality of channel data;
Selecting means for selecting and outputting any one of the plurality of channel data;
Decoding means for respectively decoding the first data and the second data included in the channel data output by the selection means;
Detecting means for detecting that the quality of the data has deteriorated to a preset level or less based on the detection result of the error detecting means;
When the detecting means detects that the level has deteriorated below the level, the selecting means is controlled to replace the first data contained in the channel data already selected and output by the selecting means. When the first data is output and then a preset condition is satisfied, it is included in the other channel data instead of the second data included in the channel data selected and output by the selection means And a control means for outputting the second data.   The broadcast receiving apparatus according to any one of claims 1 to 4, wherein the preset condition is an elapsed time after the first data is switched. One of the first data and the second data is composed of audio data and the other is composed of video data,
2. The preset condition is detection of silence in the case of audio data, and detection of a screen with low luminance or detection of a state with low temporal correlation in the case of video data. 4. The broadcast receiving device according to any one of 4. Receiving means for receiving radio signals each including first data and second data;
Demultiplexing means for demodulating the radio signal received by the receiving means and separating the radio signal into a plurality of channel data each including first data and second data;
Selecting means for selecting and outputting any one of the plurality of channel data;
Decoding means for decoding the first data and the second data of the channel data output by the selection means,
Detecting means for obtaining a correlation for each of the first data and the second data decoded by the decoding means, and detecting that the correlation has deteriorated to a predetermined level or less;
When the detecting means detects that the level has deteriorated below the level, the selecting means is controlled to include the first data or the second data corresponding to the correlation deteriorated below the level in other channel data. Control means for switching the first data or the second data to the other channel data after switching to the first data or the second data and satisfying a preset condition after that. A broadcast receiving apparatus comprising:   8. The broadcast receiving apparatus according to claim 7, wherein the preset condition is an elapsed time since the first data or the second data is switched. One of the first data and the second data is composed of audio data and the other is composed of video data,
8. The preset condition according to claim 7, wherein silence is detected in the case of audio data, and detection of a screen with low luminance or detection of a state with low temporal correlation is detected in the case of video data. The broadcast receiving apparatus described.

Images