JP2009290279A - Digital broadcast receiver and reception method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a digital broadcast receiver for reproducing video images without errors even in the state that the reception state of digital broadcast waves changes. <P>SOLUTION: The digital broadcast receiver includes: a plurality of reception parts (201-209) for receiving the digital broadcast waves and demodulating the digital broadcast waves to stream data; a plurality of decoding parts (210-212) for decoding the stream data output by the respective reception parts to display image data corresponding to each of the plurality of reception parts; an error table (213) for recording the error information of the display image data corresponding to the respective decoding parts; a composition part (214) for, while error information is recorded by the respective decoding parts in decoding, selecting the display image data without errors on the basis of the error information from the display image data output by the respective decoding parts and composing display images; and a display part (215) for displaying the display images. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a digital broadcast receiving apparatus.

  Digital broadcast (ISDB-T) receivers have become widespread and have been widely introduced in vehicle-mounted televisions and the like. In a digital broadcast receiving apparatus in a mobile environment, the reception state of a digital broadcast wave constantly changes under the influence of fading or the like. Therefore, depending on the reception state, the display image may not be normally reproduced. The following technologies are disclosed as related technologies for solving such problems.

  Patent Document 1 discloses a digital broadcast receiving apparatus that can reduce the occurrence of a decrease in reception quality during mobile reception in a digital broadcast apparatus that receives digital broadcasts. The digital broadcast receiving apparatus disclosed in Patent Document 1 demodulates a plurality of antennas, a plurality of tuner units that input signals received by the antennas to select digital broadcast waves, and a broadcast wave selected by the tuner unit. A plurality of demodulation units, a plurality of reception quality detection units for detecting the quality of received radio waves, a determination unit for determining each reception quality from a plurality of outputs of the reception quality detection unit, and outputs of a plurality of front end units A selection unit that selects a signal from the signal, and a control unit that controls the plurality of tuner units and the plurality of demodulation units, and the selection unit selects one of the plurality of demodulated signals based on the result determined by the determination unit. It is characterized by selecting one.

  The digital broadcast receiving apparatus disclosed in Patent Document 1 detects the reception quality of digital broadcast waves received by a plurality of antennas using a reception quality detection unit, and determines the best detection output among the reception qualities of the plurality of antennas using a determination unit. The video is reproduced using the digital broadcast wave received by the antenna.

JP 2002-246930 A

  Here, the digital broadcast receiving apparatus of Patent Document 1 determines the reception quality of a digital broadcast wave based on the received electric field strength for each antenna and the error rate at the time of demodulation. For this reason, it is possible to determine a reception radio wave having a good reception state. However, if there is an error in the stream data decoding process, error correction cannot be performed. This is because whether or not normal video can be reproduced from the stream data can be determined only after decoding.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a digital broadcast receiving apparatus that can reproduce an error-free video even in a state in which a digital broadcast wave reception state changes.

  Hereinafter, means for solving the problem will be described using the numbers used in (Best Mode for Carrying Out the Invention). These numbers are added to clarify the correspondence between the description of (Claims) and (Best Mode for Carrying Out the Invention). However, these numbers should not be used to interpret the technical scope of the invention described in (Claims).

  The digital broadcast receiving apparatus of the present invention receives a digital broadcast wave, and demodulates the digital broadcast wave into stream data. Each of the plurality of reception units corresponds to each of the plurality of reception units. A plurality of decoding units (210 to 212) that decode the stream data output from the receiving unit into display image data, an error table (213) that records error information of the display image data corresponding to each decoding unit, and an error Information is recorded by each decoding unit at the time of decoding, and from among the display image data output from each decoding unit, display image data having no error is selected based on error information, and a combining unit (214) for combining the display images And a display unit (215) for displaying a display image.

  In the digital broadcast receiving method of the present invention, a plurality of receiving units receive digital broadcast waves and demodulate them into stream data, and a plurality of decoding units corresponding to each of the plurality of receiving units output each receiving unit. The step of decoding stream data into display image data, the step of recording error information of display image data corresponding to each of the decoding units at the time of decoding, and the display image data output from each decoding unit are converted into error information. A step of selecting display image data having no error on the basis thereof and synthesizing the display image; and a step of displaying the display image.

  ADVANTAGE OF THE INVENTION According to this invention, the digital broadcast receiver which can reproduce | regenerate an image | video without an error can be provided even in the state in which the reception state of a digital broadcast wave changes.

  A digital broadcast receiving apparatus according to an embodiment of the present invention will be described below with reference to the accompanying drawings.

[Description of configuration]
First, the configuration of the digital broadcast receiving apparatus according to the present embodiment will be described with reference to FIG. FIG. 1 shows a configuration of a digital broadcast receiving apparatus according to this embodiment. The digital broadcast receiving apparatus 200 according to this embodiment includes antennas 201, 202, and 203, tuner units 204, 205, and 206, demodulation units 207, 208, and 209, decoding units 210, 211, and 212, and an error block information table. (Hereinafter referred to as an error table) 213, a combining unit 214, and a display unit 215.

  As shown in FIG. 1, the antenna 201 is connected to a tuner unit 204, the tuner unit 204 is connected to a demodulation device 207, and the demodulation device 207 is connected to a decoding device 210. Similarly, an antenna 202, a tuner unit 205, a demodulator 208, and a decoder 211 are connected. Similarly, an antenna 203, a tuner unit 206, a demodulator 209, and a decoder 212 are connected.

  First, the antennas 201, 202, and 203 will be described. Antennas 201, 202, and 203 receive digital broadcast waves transmitted from a broadcast station after OFDM modulation. The antennas 201, 202, and 203 are generally installed at a certain distance from each other. Therefore, the reception state of the digital broadcast wave differs depending on each antenna.

  Next, the tuner units 204, 205, and 206 will be described. The tuner units 204, 205, and 206 input digital broadcast waves from the connected antennas 201, 202, and 203, respectively, and select a predetermined frequency band. Tuner sections 204, 205, and 206 output received signals in the selected frequency band to demodulation sections 207, 208, and 209 connected thereto, respectively.

  Next, the demodulation units 207, 208, and 209 will be described. Demodulating sections 207, 208, and 209 perform stream demodulation on the received signal and acquire stream data. Demodulating sections 207, 208, and 209 output the stream data to decoding sections 210, 211, and 212 connected thereto, respectively.

  Next, the decoding units 210, 211, and 212 will be described. The decoding units 210, 211, and 212 decode stream data. In digital broadcasting (ISDB-T), techniques such as MPEG-2 and H264 / AVC are used to compress video data. In MPEG-2 and H264 / AVC, one screen (one frame) of a continuous display image is divided into blocks provided in units of 8 × 8 pixels (or 16 × 16 pixels), and encoding is performed in units of blocks. Video data encoded in units of blocks is stored in a TS (Transport Stream) packet, and timing data indicating the display timing of a display image including the block is added to be transmitted as stream data. When the decoding units 210, 211, and 212 receive stream data from the corresponding demodulation units 207, 208, and 209, respectively, encoding is performed in units of blocks. When there is an error in the block decoded by the internal stream processor, the decoding units 210, 211, and 212 generate error information of the block. The decoding units 210, 211, and 212 record error information generated corresponding to each block in the display image at each display timing in the error table 213. The decoding units 210, 211, and 212 output the decoded display image data (hereinafter referred to as display image data) to the combining unit 214.

  Next, the error table 213 will be described. The error table 213 records error information of a block having an error in the display image at each display timing (hereinafter referred to as an error block) corresponding to each of the decoding units 210, 211, and 212. In the error table 213, error information is recorded from each of the decoding units 210, 211, and 212. 2A and 2B show examples of the error table 213. FIG. Referring to FIG. 2A, the “display timing” column indicates the timing for displaying the block. In this embodiment, serial numbers are entered for simplicity of explanation. Therefore, the recording format in the “display timing” column is not limited to this. The “decoding part number” column is an identification number of a decoding part that has decoded the block. In this embodiment, for the sake of simplicity, the code of each decoding unit is entered. Therefore, the recording format in the “decoding part number” column is not limited to this. The “block number” column indicates the scanning order of blocks included in the display timing. In this embodiment, for simplification, the number of blocks is described as 16 blocks of 4 × 4. For this reason, the recording format in the “block number” column is not limited to this. The “error” column indicates that there was an error by “1” or “0”. In the error column, “1” is recorded when there is an error, and “0” is recorded when there is no error. In FIG. 2A, since only blocks with errors are recorded, the “error” column is all “1”. The recording format in the “error” column is not limited to this. Referring to the top record in FIG. 2A, when the display timing is “345”, the decoding unit 210 indicates that there is an error in the decoded display image at the block number “5”. As described above, the error table 213 records error information corresponding to each block of the display image at each display timing corresponding to each decoding unit.

  Note that the recording format of the error table 213 is not limited to this format. FIG. 2B shows another format of the error table 213. Referring to FIG. 2B, (a) records the decoding state of all the blocks in the display image at the display timing “345” in the decoding unit 210. Referring to the top record in (a), the decoding unit 210 indicates that there is no error in the block number “1” in the display image at the display timing “345”. Similarly, (b) records the decoding state of all the blocks in the display image at the display timing “345” of the decoding unit 211. Furthermore, (c) records the decoding state of all the blocks in the display image of the display timing “345” of the decoding unit 212. Thus, data may be recorded for each decoding unit. In addition, there may be other recording formats.

  Next, the synthesis unit 214 will be described. The synthesizing unit 214 receives display image data from the decoding units 210, 211, and 212, and synthesizes a display image for each display timing. Here, the display image is one screen (one frame) displayed by the display unit 215 at each display timing. In the present embodiment, the synthesis unit 214 generates a display image based on display image data after decoding input from the decoding unit 210. When there is an error block in the display image at each display timing input from the decoding unit 210, the combining unit 214 adds an error to the specific block in the display image at the same display timing input from the decoding unit 211 or the decoding unit 212. Investigate if there is any. When there is no error in the specific block in the display image of the same display timing input from the decoding unit 211 or the decoding unit 212, the synthesis unit 214 and the error block of the decoding unit 210 or the error of the decoding unit 211 or 212 The image data with a block without a block (hereinafter referred to as a normal block) is replaced in units of blocks. Hereinafter, display image data in units of blocks is referred to as block display image data. In this way, the synthesizer 214 synthesizes a display image without an error. The combining unit 214 outputs the combined display image to the display unit 215.

  FIG. 3 shows display image block replacement processing performed by the composition unit 214. With reference to FIGS. 3 and 2B, the display image data exchange processing at a certain display timing performed by the synthesis unit 214 will be described. In order to simplify the description, it is assumed that the display image has 16 blocks in one image (one frame). Note that the number of block divisions of the display image is not limited to this. Further, it is assumed that the display image used for the description is an image to be reproduced at a display timing of “345”. The display timing designation method is not limited to this.

The combining unit 214 inputs display image data after decoding from the decoding units 210, 211, and 212. Decoded images 300, 301, and 302 are display images based on display image data input from the decoding units 210, 211, and 212, respectively. Also, (a), (b), and (c) of FIG. 2B show the error tables 213 of the decoding units 210, 211, and 212, respectively, as described above. In FIG. 2B, (a), (b), and (c) each record error information corresponding to each block of the display image at the display timing “345”.
As described above, the synthesis unit 214 replaces the block display image data based on the display image data of the decoding unit 210. The synthesizing unit 214 searches the error table 213 (FIG. 2B (a)) and checks whether there is an error in each block of the display image data at the display timing “345” from the decoding unit 210. The synthesizing unit 214 detects that an error exists in the block number “5” from the error table 213 of the decoding unit 210. An error block 400 of the decoded image 300 indicates an error of the block number “5” in the decoded image 300.
The synthesizing unit 214 searches the error table 213 (FIG. 2B (b)) to replace the block number “5” included in the display image of the decoding unit 210 with the block display image data of another decoding unit. In the display image of the display timing “345” from the decoding unit 211, it is investigated whether or not there is an error in the block number “5”. Referring to FIG. 2B (b), there is no error in the block number “5” of the decoded image of the decoding unit 211 at the display timing 345. The normal block 420 indicates that there is no error in the block number “5” in the decoded image 301. As a result of searching the error table 213, the combining unit 214 detects that there is no error in the block number “5” in the display image at the display timing “345” from the decoding unit 211. The combining unit 214 outputs the block display image data of the block number “5” in the display image of the display timing “345” from the decoding unit 210 and the block number “5” of the display image of the display timing “345” from the decoding unit 211. The block display image data is replaced. This means that the error block 400 of the decoded image 300 is replaced with the normal block 420 of the decoded image 301.

Further, the synthesis unit 214 searches the error table 213 (FIG. 2B (a)) and checks whether there is an error in another block in the display image at the display timing “345” from the decoding unit 210. The composition unit 214 detects that an error exists in the block number “12” of the display image at the display timing “345” from the decoding unit 210. The error block 410 of the decoded image 300 indicates that there is an error in the block number “12” in the decoded image 300.
The combining unit 214 replaces the block display image data of the block number “12” in the display image of the decoding unit 210 with the block display image data in the display image of the other decoding unit, so that the error table 213 (FIG. 2B (b )). The synthesizing unit 214 searches the error table 213 (FIG. 2B (b)) and checks whether there is an error in the block number “12” in the display image at the display timing “345” of the decoding unit 211. However, referring to FIG. 2B (b), an error also exists in the block number “12” in the display image at the display timing “345” from the decoding unit 211. The error block 430 indicates that there is an error in the block number “12” in the decoded image 301. As a result of searching the error table 213, the combining unit 214 detects that an error exists in the block number “12” in the display image at the display timing “345” from the decoding unit 211.
In this case, the synthesis unit 214 further searches the error table 213 and examines error information of other decoding units. The synthesizing unit 214 searches the error table 213 (FIG. 2B (c)) to search whether there is an error in the block number “12” in the display image at the display timing “345” from the decoding unit 212. Referring to FIG. 2B (c), there is no error in the block number “12” in the display image at the display timing “345” of the decoding unit 212. The normal block 440 indicates that there is no error in the block number “12” in the decoded image 302. As a result of searching the error table 213, the combining unit 214 detects that there is no error in the block number “12” in the display image at the display timing “345” of the decoding unit 212. The combining unit 214 outputs the block display image data of the block number “12” in the display image of the display timing “345” from the decoding unit 210 and the block number “12” of the display image of the display timing “345” from the decoding unit 212. The block display image data is replaced. This means that the error block 410 of the decoded image 300 is replaced with the normal block 440 of the decoded image 301.

Furthermore, there may be an error in the block number “12” in the display image at the display timing “345” from the decoding unit 212. In this case, the composition unit 214 determines that the block cannot be replaced because there is an error in the block number “12” in the display images from all the decoding units. The combining unit 214 combines the display image with the block display image data of the block number “12” in the display image at the timing “345” from the decoding unit 210 in which an error exists.
Further, when the digital broadcast receiving terminal device is provided with another decoding unit, the combining unit 214 may search the error table 213 for error information of all the decoding units.

In this way, when there is an error in a specific block of the decoded image 300 serving as a reference, the synthesis unit 214 has an error in the block display image data of the error block and a block at the same position as the error block. The block display image data in the decoded image of the other decoding unit that is not performed is exchanged in units of blocks. Therefore, the composition unit 214 can generate a display image without error. In the above example, the error block 400 of the decoded image 300 and the normal block 420 of the decoded image 301 are replaced, and the error block 410 of the decoded image 300 and the normal block 440 of the decoded image are replaced. . In the decoded image 304, it can be confirmed that all the blocks are normal blocks.
The synthesizing unit 214 performs block display image data replacement processing based on the display image from the decoding unit 210. However, this is not performed on the basis of a specific decoding unit. By selecting, the display image may be synthesized.

  Next, the display unit 215 will be described. The display unit 215 displays the display image input from the synthesis unit 214.

  The above is the description of the configuration of the present embodiment.

[Description of operation method]
Next, the operation method of the digital broadcast receiving apparatus in this embodiment will be described with reference to FIGS. First, FIG. 4 illustrates an operation method of the decoding units 210, 211, and 212 of the digital broadcast receiving apparatus in the present embodiment. FIG. 4 shows an operation flow of the decoding units 210, 211, and 212 of the digital broadcast receiving apparatus in the present embodiment. Since the decoding units 210, 211, and 212 have the same operation method, the following description will be made with the decoding unit 210 as an example.

(Step S10)
The decoding unit 210 receives stream data received by the antenna 201, selected by the tuner unit 204, and demodulated by the demodulation unit 207. The decoding unit 210 initializes the error table 213. The decoding unit 210 may initialize the error table 213 every time decoding processing for each display image screen (frame) is completed.

(Step S20)
The decoding unit 210 performs decoding from the stream data for each block among the blocks included in the display image.

(Step S30)
When decoding for one block is completed, the decoding unit 210 determines whether there is an error in the block display image data. If an error exists, the process proceeds to step S40 to record error information. On the other hand, if there is no error, the process proceeds to step S50 to proceed to the next process.

(Step S40)
When there is an error in the decoded block display image data, the decoding unit 210 records error information of the block in the error table 213. As shown in FIG. 2A or 2B, the decoding unit 210 records the display timing, the identification number of the decoding unit, the block number, and the error flag in the error table 213. Note that the recording format and recording items in the error table 213 are not limited to these.

(Step S50)
When the decoding process for one block is completed, the decoding unit 210 determines whether the process has been completed for all the blocks of one display image (frame). If there is a block that has not been processed in one screen, the process returns to step S20. When the decoding process is completed for all the blocks of one screen, the display image data after decoding is output to the synthesizing unit 214, and this operation method ends.

  The above is the description of the operation method of the decoding process of the decoding unit 210 of the digital broadcast receiving apparatus in the present embodiment. By this operation method, the decoding process for one display image at a certain display timing is completed. Further, the error information of the blocks included in the display image 1 screen is recorded in the error table 213 by this operation method. Although the description is omitted, the decoding unit 211 and the decoding unit 212 similarly operate in the same manner.

  Next, the operation method of the synthesizing unit 214 of the digital broadcast receiving apparatus in this embodiment will be described with reference to FIG. FIG. 5 shows an operation flow of the synthesizing unit 214 of the digital broadcast receiving apparatus in the present embodiment. In the following description of the operation method, an operation method for a display image at a certain display timing among continuous display images will be described as an example.

(Step S100)
The combining unit 214 inputs display image data for one display image after decoding from the decoding units 210, 211, and 212, respectively. The combining unit 214 selects one block from the image data for one screen of the display image input from the decoding unit 210 that is a reference for combining the display images. The combining unit 214 searches the error table 213 and extracts error information corresponding to one selected block (hereinafter, selected block) from the error information corresponding to the decoding unit 210. In the present embodiment, the display image is generated based on the decoded image of the decoding unit 210. However, the reference decoded image may be the image of the decoding unit 211 or the image of the decoding unit 212.

(Step S110)
The synthesizing unit 214 determines whether an error is recorded in the “error” of the error information of the selected block extracted from the error table 213. If “1” is recorded in the error column of the error information corresponding to the selected block, and there is an error in the image data of the selected block, the process proceeds to step S130. On the other hand, if “0” is recorded in the error column of the error information corresponding to the selected block and there is no error in the image data of the selected block, the process proceeds to step S120.

(Step S120)
When there is no error in the selected block, the composition unit 214 determines the image of the selected block as the display image of the block in the display image.

(Step S130)
When there is an error in the selected block, the synthesis unit 214 determines whether there is another decoding unit capable of examining the error information of the selected block in order to replace the block display image data. If there is another decoding unit that can be investigated, the process proceeds to step S140 in order to investigate error information of the other decoding unit. On the other hand, when the error information investigation of the selected block has been completed for all the decoding devices and there is no other decoding unit that can perform the investigation, the synthesizing unit 214 changes the selected block of the decoding unit 210 to The display image of the block in the display image is determined. In this case, the process proceeds to step S170.

(Step S140)
The combining unit 214 checks error information of other decoding units that have not been checked for error information. The synthesizing unit 214 extracts error information of the selected block from error information corresponding to other decoding units recorded in the error table 213.

(Step S150)
The synthesizing unit 214 determines whether an error is recorded in the “error” of the error information of the selected block in the other decoding unit extracted from the error table 213. In the error information of the selected block in the other decoding unit, “1” is recorded in the error column, and when there is an error in the image data of the selected block in the other decoding unit, the error information of the other decoding unit is further displayed. In order to investigate, it returns to step S130. On the other hand, in the error information of the selected block in the other decoding unit, “0” is recorded in the error column, and when there is no error in the image data of the selected block in the other decoding unit, the process proceeds to step S160.

(Step S160)
When there is no error in the selected block of the other decoding unit, the synthesizing unit 214 replaces the block display image data of the selected block of the decoding unit 210 with the block display image data of the selected block of the other decoding unit. . The combining unit 214 determines the display image of the selected block of the other decoding unit after replacement as the display image of the block in the display image. As a result, the selected block of the display image is in an error-free state.

(Step S170)
The composition unit 214 determines whether or not the investigation has been completed for all the blocks included in the one display image screen. If the survey has not been completed for all the blocks, the process returns to step S100 to investigate another block. On the other hand, when the survey for all the blocks is completed, a display image for one screen is output to the display unit 215, and this operation ends.

The above is the description of the operation method of the synthesizing unit 214 in the digital broadcast receiving apparatus of the present embodiment. The digital broadcast receiving apparatus repeats this operation method for each screen of the display image, and replaces the error block present in the display image after decoding with a normal block without error. Therefore, a display image in which an error block exists after decoding can be corrected to a display image without an error block.
In step S100, the composition unit 214 selects a selected block from among the blocks existing on one display screen. In this selection method, blocks may be selected in the order in which the display unit 215 scans the display screen. The order of selecting blocks is not particularly limited. Further, the synthesis unit 214 searches for error information of other decoding units in the error table 213 in order to replace error blocks. In this case, the selection order of the other decoding units is not particularly limited. For example, an operation method may be used in which statistics of error information of each decoding device are collected and selected and investigated in ascending order of error rate.

The above is the description of the present embodiment. As described above, the decoding units 210, 211, and 212 record error information in units of blocks in the error table 213 when there is a data error after decoding in the decoding process for each block. When there is an error in the selected block of the decoded image 300 serving as a reference, the synthesizer 214 searches for the selected block of the other decoding unit and blocks the selected block and the image data of the other decoding unit in which no error exists. Swap in units. Therefore, the composition unit 214 can generate a display image without error. Since these processes are performed after decoding of the display image, it is possible to correct an error in the image data to be actually displayed.
In the above embodiment, the block display image data of the display image is replaced in units of blocks. However, the display image may be replaced in units of one screen. In this case, each decoding unit records error information in the error table 213 for each screen of the display image, and the combining unit 214 selects a display screen depending on whether there is an error for each screen of the display image and displays the display unit 215. May be displayed. Alternatively, the synthesis unit 214 may select a display screen with a small number of error blocks on the display screen 1 screen and display it on the display unit 215.

  Although the present invention has been described with reference to the embodiments, the present invention is not limited to the above-described embodiments. Various changes that can be understood by those skilled in the art can be made to the configuration and details of the present invention within the scope of the present invention.

It is a figure which shows the structure of the digital broadcast receiver in this embodiment. It is a figure which shows the example of the error table. It is a figure which shows the example of the error table. It is a figure which shows the block replacement process of the display image which the synthetic | combination part 214 performs. It is an operation | movement flow of the decoding parts 210, 211, and 212 of the digital broadcast receiver in this embodiment. It is an operation | movement flow of the synthetic | combination part 214 of the digital broadcast receiver in this embodiment.

Explanation of symbols

200 Digital Broadcasting Receiver 201 Antenna 202 Antenna 203 Antenna 204 Tuner Unit 205 Tuner Unit 206 Tuner Unit 207 Demodulation Unit 208 Demodulation Unit 209 Demodulation Unit 210 Decoding Unit 211 Decoding Unit 212 Decoding Unit 213 Error Block Information Table 214 Synthesis Unit 215 Display Unit 300 Decoded image 301 Decoded image 302 Decoded image 304 Decoded image 400 Error block 410 Error block 420 Normal block 430 Error block 440 Normal block

Claims (6)

A plurality of receivers that receive digital broadcast waves and demodulate the digital broadcast waves into stream data;
Corresponding to each of the plurality of receiving units, a plurality of decoding units that decode the stream data output from each receiving unit into display image data;
An error table for recording error information of the display image data corresponding to each of the decoding units;
The error information is recorded by each decoding unit during the decoding,
From the display image data output by each decoding unit, a combining unit that combines the display image by selecting the display image data without the error based on the error information;
A digital broadcast receiving apparatus comprising: a display unit that displays the display image. The digital broadcast receiver according to claim 1,
The display image is divided into a plurality of blocks each including a plurality of pixels.
The decoding unit performs the decoding of each of the plurality of blocks for each of the blocks, and records block error information for each block in the error table in association with the decoding unit,
The synthesis unit synthesizes the display image by selecting the display image data without error from the display image data output from the decoding units on a block basis based on the block error information. Broadcast receiving device. The digital broadcast receiver according to claim 2,
The synthesizing unit selects one selection decoding unit from the decoding units, selects a selection block in the block unit in the display image data output from the selection decoding unit, and selects the selection block from the error table. The block error information corresponding to the selected block is checked, and when there is an error in the selected block, the block error information of the other device selected block corresponding to the selected block in the display image data output from another decoding unit is If there is no error in the other device selection block after checking from the error table, the display image data of the selected block and the display image data of the other device selection block are switched to synthesize the display image. Digital broadcast receiver. Receiving digital broadcast waves by a plurality of receiving units and demodulating them into stream data;
Decoding the stream data output from each receiving unit into display image data by a plurality of decoding units corresponding to each of the plurality of receiving units;
Recording error information of the display image data corresponding to each of the decoding units at the time of decoding;
Selecting the display image data without the error based on the error information from the display image data output by each decoding unit, and combining the display image;
A digital broadcast receiving method comprising: displaying the display image. The digital broadcast receiving method according to claim 4,
The display image is divided into a plurality of blocks each including a plurality of pixels.
The decoding step includes:
Decoding each of the plurality of blocks for each block;
The step of recording comprises:
Recording block error information for each block in the error table in association with each decoding unit;
The synthesizing step includes:
Digital broadcasting including a step of selecting the display image data without error from the display image data output from each decoding unit in units of blocks based on the block error information and synthesizing the display image Reception method. 6. The digital broadcast receiving method according to claim 5, wherein the step of selecting in units of blocks and synthesizing the display image include:
Selecting one selected decoding unit from each of the decoding units;
Selecting a selection block in units of blocks in the display image data output by the selection decoding unit;
Examining the block error information corresponding to the selected block from the error table;
When there is an error in the selected block, examining the block error information of the other device selection block corresponding to the selected block in the display image data output from another decoding unit from the error table;
If there is no error in the other device selection block, the display image data of the selected block and the display image data of the other device selection block are replaced to synthesize the display image. Method.

Images