JP2006197420A - Broadcast receiver - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a broadcast receiver capable of eliminating the dissatisfaction that characters superimposed by a broadcasting station side are so small that they can be hard to be looked at on a display. <P>SOLUTION: An OCR processing part 13a performs superimposition area determination processing and recognition processing of superimposed characters. In the superimposition area determination processing, inter-dot luminance difference and the gathering degree of dots having not less than fixed luminance, or the like are detected about received video data in the width of 20 dots around the received video data. The OCR processing part 13a performs optical character recognition processing of an area estimated to have characters and transfers a generated text code to a CPU 13. When the CPU 13 receives the text code from the OCR processing part 13a, the CPU 13 converts the text code into a certain font of a certain size and supplies the resultant text code as OSD (on-screen display) data to an OSD circuit 12. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a broadcast receiving apparatus that receives a television broadcast.

In digital television broadcasting and analog television broadcasting, caption supervision and the like are broadcast on the broadcast video by superimposing (superimposing) on the broadcast video (see Patent Document 1).
JP-A-9-83868

  However, when the size of characters superimposed on the broadcast station side is small, it may be difficult to see the characters on the received video. In particular, in recent years, a small broadcast receiving apparatus such as a mobile phone with a TV has been proposed, and the screen of such a small broadcast receiving apparatus is so small that character recognition becomes more difficult.

  In view of the above circumstances, an object of the present invention is to provide a broadcast receiving apparatus that can eliminate the dissatisfaction such that characters superimposed on the broadcast station side are small and difficult to see on the display.

  In order to solve the above problem, the broadcast receiving apparatus of the present invention has recognized means for receiving broadcast waves and generating video, and means for recognizing superimposed characters in the received video. It is characterized by comprising means for imaging a character and means for displaying the imaged character on a display.

  In the above configuration, the recognized character size should be enlarged and imaged, but even if the character size is not enlarged, the character is selected by appropriately selecting the character color, background color, etc. It becomes easy to see. In these configurations, at least one of the recognized character size, font, character color, and background color of the character image display area may be changed by a user operation.

  In the broadcast receiving apparatus configured as described above, the received video is displayed on the display, and the imaged characters may be displayed over the area where the characters of the received video are displayed. Alternatively, the received video may be displayed on the display, and the imaged characters may be displayed so as not to overlap the display area of the received video. Alternatively, the display on which the imaged characters are displayed may be a sub display different from the display on which the received video is displayed. When the sub display is provided, the sub display may be provided with a lens for image enlargement.

  Further, the broadcast receiving apparatus of the present invention comprises means for receiving broadcast waves to generate video, means for performing image enlargement processing of a display area of characters superimposed in the received video, and received video Means for displaying the enlarged character area image on the display to be displayed so as not to overlap the received video.

  Further, the broadcast receiving apparatus of the present invention comprises means for receiving broadcast waves to generate video, means for performing image enlargement processing of a display area of characters superimposed in the received video, and received video Means for displaying the enlarged character area image on a sub-display different from the display to be displayed.

  Further, the broadcast receiving apparatus of the present invention includes means for receiving broadcast waves to generate video, means for performing image extraction or image enlargement processing of a display area of characters superimposed in the received video, And means for displaying the extracted or enlarged character area image on a sub-display having a lens for image enlargement different from the display on which the received video is displayed.

  The broadcast receiving apparatus according to the present invention also includes means for receiving broadcast waves to generate video, means for recognizing superimposed characters in the received video, and means for storing the recognized character string. And means for performing communication through a network, and means for transmitting the character string when performing the communication.

  The said structure WHEREIN: You may be comprised so that it may be discriminate | determined automatically whether the said character string is an electronic mail address or the description which specifies the arrival method to the resource which exists on the net | network.

  In the broadcast receiving apparatus configured as described above, an area that is a target of the character recognition, the image enlargement process of the character display area, or the image extraction process of the character display area may be a peripheral area other than the center of the received video. .

  The broadcast receiving apparatus having these configurations may be configured to estimate the presence of characters in the received video based on the luminance change of the dots constituting the received video. In such a configuration, the presence of a character may be estimated on the condition that there is no change in luminance of the corresponding dot between a plurality of frames of the received video.

  Further, the broadcast receiving apparatus having these configurations may be configured as a portable type or a mobile type that receives a terrestrial broadcast.

  According to the present invention, there are various effects such that it is possible to eliminate the dissatisfaction that the characters superimposed on the broadcasting station side are small and difficult to see on the display.

  A broadcast receiving apparatus according to an embodiment of the present invention will be described below with reference to FIGS. Here, a digital terrestrial broadcast receiver configured as a mobile phone with a TV is illustrated.

  FIG. 1 is a block diagram showing a mobile phone 10 with a TV. The mobile phone with TV 10 includes a telephone function unit 30 and a digital broadcast receiving unit 20. The telephone function unit 30 includes a control unit 31, a wireless communication unit 32, a voice processing unit 33, a memory unit 34, a key input unit (operation unit) 35, a display unit (for example, a liquid crystal panel) 36, data And a processing unit 37. The voice signal received in the normal telephone process is given to the speaker 38 via the voice processing unit 33, while the voice uttered by the user is converted into a voice signal by the microphone 39 and subjected to processing such as amplification by the voice processing unit 33. The audio signal is sent out by the wireless communication unit 32. The data processing unit 37 performs processing on the received packet. The wireless communication unit 32 performs voice and data transmission / reception processing and predetermined protocol processing (transmission time processing and reception time processing) with the base station 60. The control unit 31 performs overall control in the telephone function unit 30 and performs processing for cooperation with the digital broadcast receiving unit 20. For example, as a basic process, when the TV function activation key is turned on in the key input unit 35, an ON command is given to the digital broadcast receiving unit 20, and the video output from the digital broadcast receiving unit 20 is displayed on the display unit 36. A process of giving the digital broadcast receiving unit 20 a channel selection command with the number as a channel number when the numeric keypad of the key input unit 35 is operated is performed.

  The control unit 31 also functions as a mail processing unit and a Web client unit. The wireless communication unit 32 performs communication processing during operation of the Web client unit, communication processing during mail communication operation, and the like. The control unit 31 functioning as a Web client unit transmits a notation (URL or the like) specifying a method of reaching a resource existing on the Internet, and stores a file transmitted from the resource side in the memory unit 34 And processing to generate display image data by interpreting the file. The control unit 31 functioning as a mail transmission / reception unit performs a process of receiving a mail from a mail server on the Internet or transmitting a mail address and a mail text to the mail server. The email address and URL may be acquired by OCR processing, which will be described later, instead of manual input by the user.

  Next, the digital broadcast receiver 20 will be described with reference to FIG. The terrestrial antenna 1 gives the received signal to the terrestrial digital tuner 2. The terrestrial digital tuner 2 extracts a signal having a specific frequency from the high-frequency digital modulation signal including video / audio data. The terrestrial digital tuner 2 includes a demodulation circuit, a deinterleave circuit, an error correction circuit, etc., and demodulates the selected digital modulation signal to output a transport stream.

  The demultiplexer (DEMUX) 3 sends the transport stream to the H.264 in IEEE. H.264 video stream, audio stream, PSI / SI (Program Specific Information / Service Information), broadcast information (region identifier, service type, broadcast station identification, service number, remote control key ID), etc. The demultiplexer 3 supplies the video stream and the audio stream to the AV decoder 4 and supplies PSI / SI, broadcast information and the like (these information is called program information) to the CPU 13.

  The AV decoder 4 includes a video decoder that decodes a video stream and an audio decoder that decodes an audio stream. The video decoder decodes an input encoded signal to obtain a quantization coefficient and a motion vector, and performs inverse DCT transform, motion compensation control based on the motion vector, and the like. The audio decoder decodes the input encoded signal to generate audio data. The video data generated by the decoding is stored in a frame buffer memory (SDRAM or the like) 7 for four frames, sequentially read from the old frames and output to the video processing circuit 5, and the audio data is output to the audio processing circuit 6. The

  The video processing circuit 5 receives video data from the frame buffer memory 7 and generates, for example, RGB data. The RGB data is given to the display unit (liquid crystal panel or the like) 36 for video display. The audio processing circuit 6 receives the audio data output from the AV decoder 4 and performs D / A conversion to generate, for example, a right (R) sound analog signal and a left (L) sound analog signal. These audio signals are supplied to the speaker 38 or a speaker (not shown) provided separately from the telephone.

  An OSD (on-screen display) circuit 12 adds video data based on character information and color information instructed to be output from the CPU 13 to an adder (this adder may be a drawing memory (VRAM) in the display unit 36) 20. Output. The adder 20 performs processing for incorporating the video data into the received video data output from the frame buffer memory 7. The OSD circuit 12 can perform processing such as menu screen display and text image insertion display described later.

  The memory (for example, RAM, EEPROM, flash memory, etc.) 14 has a channel table (channel list in which frequency information, broadcast station name, etc. correspond to remote control key IDs and channel numbers), program information extracted from broadcast waves, etc. Is stored.

  The OCR processing unit 13a performs a superimpose area determination process and a superimposed character recognition process. These processes will be specifically described below. Normally, the broadcasting station inserts characters (subtitles and guidance text) into peripheral areas such as the upper side, lower side, right side, and left side of the image (almost never inserted into the central area of the image). In addition, the brightness of characters is generally high.

  Here, if the received digital image is 240 (horizontal) × 320 (vertical) dots, the capacity of the frame buffer memory 7 is set to 480 × 640 dots so that image data for four frames is buffered. In addition, the drawing memory in the display unit 36 is assumed to be 240 × 340 (320 + 20) dots. In the superimpose area determination process, the brightness difference between dots or the degree of gathering of dots having a certain brightness or more is detected with a width of 20 dots around each image data. When characters are present, there are many places where a large luminance difference occurs between the dots, and it is considered that dots having a certain luminance or more are not dispersed but often exist adjacent to each other. If such a tendency indicating the presence of characters is detected at the same position for four consecutive frames, it can be estimated that characters are generally present.

  The OCR processing unit 13a performs an optical character recognition process on a peripheral area estimated to have a character. For this character recognition processing itself, an existing algorithm may be used. If the percentage of characters that cannot be recognized is greater than a certain reference value, it is processed as no text (character). When the reference value is exceeded, it is determined that there is text (character), and the generated text (character) code is passed to the CPU 13.

  The CPU 13 exchanges information with the telephone function unit 30 via the external input / output interface 9. Further, as a process according to the present invention, when the CPU 13 receives a text code from the OCR processing unit 13a, the CPU 13 converts the text code into a font of a certain size and supplies it to the OSD circuit 12 as OSD data. The OSD circuit 12 generates image data so that characters by the font exist in an area of 240 × 20 dots, and displays the image data, for example, under a received video (240 × 320).

  FIG. 3 is a flowchart showing the text output process of the mobile phone with TV. The digital broadcast receiver 20 generates video data of 240 × 320 dots (digital television video: 30 frames / second) (step S1), and sequentially stores the video data in the frame buffer memory 7 having an area for four images. (Step S2). When four images are stored (YES in step S3), the received video output process and the text determination / OCR process are performed in parallel. In the reception video output, the first image (240 × 320 dots) is sequentially transferred to the drawing memory (step S4). On the other hand, as text determination / OCR processing, the peripheral contrast of the 4-frame images is compared with a width of 20 dots (step S5), and the presence of a character is estimated (step S6). If it is estimated that no character exists, a blank image (240 × 20 dots) is created (step S7). If it is estimated that there is a character (YES in step S6), the area is subjected to OCR processing (step S8), and it is determined whether a text code has been generated (step S9). If the text code cannot be generated, the process proceeds to step S7. If the text code can be generated, the text code is output to the font conversion unit (step S10), font conversion is performed (step S11), and a text data image (240 × 20 dots) is created (step S12). Then, the text data image or blank image (240 × 20 dots) created in step S7 or step S12 is transferred to the drawing memory (step S13). Then, a text data image (or blank image) is superimposed on the received video to generate an image of 240 × 340 dots (step S14), and this image is displayed on the display unit (step S15).

  Note that the mobile phone with TV can be configured to perform both horizontal screen display and vertical screen display. In the vertical screen display, the received video is not displayed using the entire screen, but a blank area is formed in the upper or lower area of the display portion of the received video. Therefore, as described above, it is preferable that the text data image is displayed in a blank area (the area of the received video is not eroded). On the other hand, in the horizontal screen display, the received video is often displayed on the entire screen, and in this case, the text data image may be drawn on the superimposed portion of the received video (eroding the area of the received video). . Of course, even in the horizontal screen display, the received video is not displayed on the full screen, and an L-shaped blank area is formed (the received video is reduced by a scaler (not shown)), and text data is displayed in this blank area. An image may be displayed. Also, the character size, character font, character color, and background color of the character image display area are not fixed, and at least one of them can be changed by a user operation (for example, key operation of the key input unit 35, etc.). Also good. Even when a text data image is displayed with a size equivalent to the original character size, it may be easier to see the character by appropriately selecting the character color and background color, changing the font, or the like. When all the text does not fit within the screen due to the increased character size, automatic scroll display (processing such as moving the character display position several dots at a constant speed) or manual scroll display (key operation is performed) It is preferable to perform processing such as moving the character display position several dots each time. Further, the text data may be displayed on a different sub display unit (for example, an auxiliary black and white liquid crystal panel for displaying a message or the like) different from the display unit for displaying the received video. Even if the display of the text data is equivalent to the original character size, for example, by providing a lens in the sub display unit, the user can see the optically enlarged character.

  In the above embodiment, the OCR process is performed on the area when it is estimated that the character exists. However, the present invention is not limited to this, and the area is enlarged (pixels) when it is estimated that the character exists. Interpolation) or the like. The enlarged image portion may be displayed on a display unit that displays the received video in a form that does not erode the area of the received video. Further, the enlarged image portion may be displayed on a sub display unit provided with a lens. In addition, if the lens is provided in the sub display unit as described above, an area estimated to contain characters may be simply cut out and displayed on the sub display unit without being enlarged.

  On the other hand, when the OCR process described above is performed, there is an advantage that the character string obtained by the OCR process can be used in addition to the effect of making the characters easy to see. That is, when a character string such as an e-mail address or URL (uniform resource locator) is superimposed on a video and transmitted on the broadcast station side, the digital broadcast receiving unit 20 can acquire the character string as data. The character string data (e-mail address or URL) can be supplied from the digital broadcast receiving unit 20 to the control unit 31. As described above, the control unit 31 also functions as a mail processing unit and a Web client unit, and performs processing using the received e-mail address and URL. That is, the user can save time and effort to manually input an e-mail address and URL. When the presence of the “@” mark is detected in the character string, it is determined that the character string is an e-mail address. When the presence of the character string “http: //” is detected in the character string, The control unit 31 can automatically perform processing for determining that the character string is a URL. After automatic determination, for example, an email address may be registered in the email address list, and a URL may be registered in the URL list.

  In the above example, the mobile phone with TV has been described. However, the mobile phone may be configured as a portable or mobile digital broadcast receiver. Moreover, it is not limited to a portable type or a mobile type, but may be a stationary digital broadcast receiving apparatus. Moreover, it can be configured not only as terrestrial digital broadcasting but also as a receiving device for satellite (CS / BS) digital broadcasting. It should be noted that the ease of viewing the superimposed characters is likely to be a problem in portable or mobile digital terrestrial broadcast receivers, and the advantages of the present invention are more exhibited in such a configuration. In the above embodiment, the configuration for receiving a digital broadcast is shown. However, the present invention can be applied to a configuration for receiving an analog television broadcast.

It is the block diagram which showed the mobile telephone with TV of embodiment of this invention. It is the block diagram which showed the broadcast receiving part of the mobile telephone with TV of embodiment of this invention. It is the flowchart which showed the processing content of embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Mobile phone 13a OCR processing part 20 Digital broadcast receiving part 30 Telephone function part 31 Control part 32 Wireless communication part

Claims (16)

Means for receiving a broadcast wave to generate a video; means for recognizing a superimposed character in the received video; means for imaging the recognized character; and A broadcast receiving apparatus comprising: means for displaying; The broadcast receiving apparatus according to claim 1, wherein the recognized character is enlarged to form an image. 3. The broadcast receiving apparatus according to claim 1, wherein at least one of the recognized character size, font, character color, and background color of the character image display area is changed by a user operation. A broadcast receiving apparatus characterized by the above. 4. The broadcast receiving device according to claim 1, wherein a received video is displayed on the display, and the imaged characters are displayed over the area where the characters of the received video are displayed. A broadcast receiving apparatus. 4. The broadcast receiving device according to claim 1, wherein a received video is displayed on the display, and the imaged characters are displayed so as not to overlap a display area of the received video. A broadcast receiving device characterized. 4. The broadcast receiving apparatus according to claim 1, wherein the display on which the imaged characters are displayed is a sub-display different from the display on which the received video is displayed. apparatus. 7. The broadcast receiving apparatus according to claim 6, wherein the sub-display is provided with a lens for image enlargement. Means for receiving broadcast waves to generate video, means for performing image enlargement processing of a display area of a character superimposed in the received video, and displaying the received video on a display on which the received video is displayed. Means for displaying the enlarged character area image so as not to overlap, and a broadcast receiving apparatus. Means for receiving broadcast waves to generate video, means for performing image enlargement processing of a display area of characters superimposed in the received video, and a sub-display different from a display on which the received video is displayed And a means for displaying the enlarged character area image on the broadcast receiving apparatus. Separately from means for receiving broadcast waves and generating video, means for performing image extraction or image enlargement processing of a display area of characters superimposed in the received video, and a display on which the received video is displayed And a means for displaying the extracted or enlarged character area image on a sub-display having a lens for image enlargement. Means for receiving broadcast waves and generating video; means for recognizing superimposed characters in the received video; means for storing recognized character strings; means for communicating through a network; Means for transmitting the character string when performing the communication. 12. The broadcast receiving apparatus according to claim 11, wherein the broadcast receiving apparatus is configured to automatically determine whether the character string is an e-mail address or a notation that specifies a method of reaching a resource existing on the net. Broadcast receiving device. The broadcast receiving device according to any one of claims 1 to 12, wherein an area to be subjected to the character recognition, the image enlargement process of the character display area, or the image extraction process of the character display area is set as an object of the received video. A broadcast receiving apparatus characterized in that it is a peripheral area other than the center. The broadcast receiving device according to any one of claims 1 to 13, wherein the presence of characters in the received video is estimated based on a change in luminance of dots constituting the received video. A broadcast receiving device characterized. 15. The broadcast receiving apparatus according to claim 14, wherein the presence of a character is estimated on condition that there is no change in luminance of corresponding dots between a plurality of frames of received video. The broadcast receiving apparatus according to any one of claims 1 to 15, wherein the broadcast receiving apparatus is configured as a portable type or a mobile type.

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