JP4768411B2 - Mobile subtitle specification conversion device for digital broadcasting and its conversion method - Google Patents

Description

  The present invention relates to a technique for displaying subtitles in accordance with video display, for example, in terrestrial digital broadcasting, and more particularly, to a technique for realizing appropriate subtitle display on a mobile receiving terminal.

  In terrestrial digital broadcasting, which is currently in widespread use, a function to display subtitles at designated positions on the screen in accordance with the video display of the program in order to enhance the visual effect and consider viewing by the visually impaired Is included (see Non-Patent Document 1).

  By the way, in terrestrial digital broadcasting, broadcasting for portable receivers (including on-vehicle receivers) is performed simultaneously with broadcasting for fixed receivers. In this case, it is necessary to consider that the display screen of the portable receiver is extremely small compared to the display screen of the fixed receiver. That is, for a fixed receiver, even if it is possible to display a caption on the display screen below a speaker person, if the caption is superimposed on a portable receiver, video display is hindered. Therefore, in the ARIB (Association of Radio Industries and Businesses) standard of Non-Patent Document 1 above, a caption display area (outscreen) is provided separately from the video display area, and each line of the speaker character is a character string. Mobile subtitle specifications that are sequentially displayed are included.

However, in the caption data created for the fixed receiver, the display position is designated by the coordinate information for each block of the character string, but such coordinate information is not added for the portable receiver. For this reason, for example, when individual subtitles for a plurality of speaker images are displayed on a fixed receiver, there are cases where the display order of character strings is mixed and a meaningless sentence is formed on a portable receiver.
Published by The Radio Industry Association “Structure and operation of digital subtitle data transmitted in auxiliary data packet format” ARIB STD-B37 2.2 version

  As described above, in digital broadcasting, it is necessary to create a portable subtitle specification that considers the arrangement of character strings for a portable receiver separately from the subtitle display specification for a fixed receiver. However, to change the subtitle display specification for a fixed receiver once created to the mobile subtitle specification for a portable receiver, specify the arrangement order and display timing so that the display order of each block is a meaningful word. This requires a complicated editing operation.

  The present invention solves the above problems, and automatically determines the arrangement order and display timing so that the display order for each block is a meaningful word, with the caption display specifications for the fixed receiver as portable caption specifications. It is an object of the present invention to provide a portable subtitle specification conversion device for digital broadcasting that can be edited and a conversion method thereof.

  In order to solve the above problem, a portable caption specification conversion device for digital broadcasting according to the present invention provides a broadcast program for displaying captions at designated positions on a screen in accordance with video display for a fixed receiver, A mobile phone that is used in a digital broadcasting system that provides the broadcast program for a portable receiver, and that converts caption data for a fixed receiver into caption data for a portable receiver in which a caption display area is defined separately from a video display area. A subtitle specification conversion apparatus, wherein each of the character strings divided by the character string dividing means is recognized by a character string dividing means for recognizing and dividing a character string based on a predetermined recognition condition. The character string sorting means that sorts the start coordinates in order from the reference point, and the relevance of each character string sorted by the character string sorting means Based on a predetermined sort condition when there are a plurality of character blocks constructed by the character block constructing means and the character block constructing means for combining the character strings determined to be related and constructing the character block Character block sorting means for determining the order of sending the character blocks.

  Also, the portable subtitle specification conversion method for digital broadcasting according to the present invention provides a broadcast program for displaying a subtitle at a designated position on the screen in accordance with video display for a fixed receiver, and for the portable receiver. This is a mobile subtitle specification conversion method that is used in digital broadcasting systems that provide broadcast programs and converts subtitle data for fixed receivers into subtitle data for mobile receivers that have a subtitle display area defined separately from the video display area. The start coordinate is a reference point for each of the character string dividing procedure for recognizing and dividing the character string based on a predetermined recognition condition and the character string divided by the character string dividing procedure. Check the relevance of each character string sorted by the character string sorting procedure and sort by the character string sorting procedure, and determine that there is a relevance A character block construction procedure for constructing a character block by combining the character strings; and when there are a plurality of character blocks constructed by the character block construction procedure, the order of sending the character blocks based on a predetermined sort condition And a character block sorting procedure for determining.

  According to the present invention, subtitle display specifications for fixed receivers are portable subtitle specifications, and the arrangement order and display timing are automatically determined and edited so that the display order of each block is a meaningful word. It is possible to provide a portable subtitle specification conversion device for digital broadcasting and a conversion method thereof.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a schematic configuration diagram showing an authoring device for creating a broadcast program of a terrestrial digital broadcasting system having the conversion function as one embodiment of a portable caption specification conversion device according to the present invention. In FIG. 1, the input interface unit 11 displays characters (for displaying subtitles superimposed on the lower part of a speaker person on a display screen together with video data and audio data as a program data file produced for a fixed receiver). A file in which character) data (hereinafter, caption data) is multiplexed is supplied. A CPU (arithmetic processing unit) 12 loads a program registered in advance in a ROM (read only memory) 14 in accordance with a user designation input by the operation unit 13 or automatically. The program includes a portable subtitle specification conversion program that implements a character string reconstruction function.

  By executing the conversion program, the program data file supplied to the input interface unit 11 is expanded in a RAM (Random Access Memory) 15 and the display position information of the character data for the fixed receiver is stored in the portable subtitle of the portable receiver. It is converted into display control information suitable for the display area and multiplexed with video data and audio data to create a program data file for a portable receiver. Finally, the program data file is output from the output interface unit 16 to an on-air transmission device (not shown).

  The basic processing flow of the caption layout conversion program is based on mobile caption conversion guidelines shown in the ARIB standard STD-B37. The main points of this guideline are as follows.

  First, in the portable receiver, as a model case, it is defined to secure a display area of standard size 12 characters × 4 lines or standard size 16 characters × 3 lines, and the number of characters that can be displayed at one time is 48 characters.

  The layout conversion processing to portable captions is based on a method of uniformly determining one sentence along the text flow from the upper left coordinates to the lower right coordinates. When there are a plurality of sentences on one caption screen, it is desirable to display them separately. As a method of judging a plurality of sentences, a method of judging character blocks (character strings constituting one context) of the same color adjacent in the character (horizontal) direction and line direction as a unit of one sentence, characters There is a method of judging character blocks of the same color that are adjacent only in the direction as a unit of one sentence.

  When there are a plurality of sentences on one subtitle screen, it is easy to see the display by using an action position line feed (APR) between sentences using an action position line feed between sentences. However, when the mobile subtitle is inserted into the operation position, even if it is 48 characters or less, it does not fit in the mobile subtitle display area. Also, when one sentence is composed of a plurality of lines, it may be determined as a plurality of sentences depending on the sentence determination method, and may not fit in the display area by inserting a line feed at the operation position. In such a case, the operation position line feed can be deleted or replaced with another symbol such as a space.

  Under the above conditions, an outline of a portable subtitle specification conversion method (program) for realizing the character string reconstruction function of the present embodiment will be described with reference to FIG.

  First, in consideration of the visual effect, coordinate information for displaying characters is added to the caption for the fixed receiver (HD caption). On the other hand, since mobile subtitles do not have coordinate information of the display position, it is necessary to reconstruct each character string as a character block when displaying the mobile subtitles converted from HD subtitles on the out-screen of the mobile receiver. is there. FIG. 2 shows an image when the character string is reconstructed. 2A shows a fixed receiver display example, and FIG. 2B shows a portable receiver display example.

  In FIG. 2, “Character string 1” and “Character string 3” displayed on the fixed receiver are dialogues on the left side, and it is assumed that a sentence is composed of “Character string 1” + “Character string 3”. In the portable receiver, in order to be able to read the dialogue sentence without a sense of incongruity, it is necessary to recognize that the character string 1 and the character string 3 are the same character block at the time of portable subtitle conversion. A function that realizes this conversion is called a “character string reconstruction function”.

  FIG. 3 shows the basic processing flow of the conversion program for realizing this character string reconstruction function. In FIG. 3, when a program data file is input and the character string reconstruction function is started, character string division processing (step S1), character string sorting processing (step S2), character block construction processing (step S3), character Processing is performed in the order of block sort processing (step S4). Hereinafter, specific processing contents of each step will be described.

Step S1: Character string division processing
In order to realize the character string reconstruction function, the portable subtitle specification conversion program needs to hold the display area of the fixed receiver and grasp the positional relationship of each character string. The maximum display area of the fixed receiver in the portable caption specification conversion program is, for example, 960 dots wide and 540 dots high. FIG. 4 shows an example of the internal display area of the fixed receiver caption in the portable caption conversion program.

  In FIG. 4, at the start of the program, 960 × 540 dots is set as the initial value of the display area. If the display area is set by the display position designation (SDP) control and the display configuration dot designation (SDF) control in the body data unit, the display area is reset. However, if the display area set in the text data unit exceeds the area of 960 × 540 dots, the display area is not reset and is set to the initial value. If SDP and SDF are not set in the body data unit, the display area in the program is set to the initial value. When the display area specified in the body data unit exceeds the area of 960 × 540 dots, the display area is limited to 960 × 540 dots.

  In addition, in the ARIB standard STD-B37 2.2 version, the display position is 170 dots wide, 30 dots long, and the display area is 620 dots wide as “mutual conversion standard of digital subtitle data transmitted in auxiliary data packet format”. Recommended as 480 dots vertically.

  As a method for dividing the fixed receiver subtitle data into character strings, the following conditions are used. When any of the conditions is satisfied, the fixed receiver subtitle data is recognized as a character string.

(Condition 1) Division by action position control code A character code from a control code relating to a character action position to a position immediately before a control code relating to the next character action position is defined as one character string. However, if there is no character code between the operation position control code and the operation position control code, the character string is not determined. Further, even when the character string is described only in a small size and the character code included in the character string is only the space control code, it is not determined as a character string, and the character string is not to be converted.

  For example, the character code may be described by continuously using the operation position backward (APB) control, the operation position advance (APF) control, or the like. FIG. 5 shows an example of character string division by the operation position control code. That is, in FIG. 5, the range (1) is determined as a character string. The range (2) is a small character string with only a space control code, and is not subject to conversion. The range of (3) is determined as a character string. Regarding the range (4), the first APB is not determined to be a character string, but is also determined to be a character string including the second APB. Therefore, in this example, the coordinate information of the character string is the coordinates for two APBs.

(Condition 2) Division by character string display state (coordinates) (wrapping division)
When the character string divided by the operation position control code is arranged in the display area, it is checked whether the character string exceeds the display area. If it exceeds the display area, the character code following the boundary value of the display area is set as another character string. An example is shown in FIG. When divided into separate character strings, the abscissa of the character string is the left end of the display area, and the ordinate is the ordinate of the original character string + the number of vertical dots of the current character size.

  An example of the initial value of the number of character dots of the character code constituting the character string is shown in FIG. In FIG. 7, the number of character dots may be changed by character configuration dot designation (SSM) control, line interval designation (SVS) control, or character interval designation (SHS) control. Further, since each character size is configured based on the “standard size”, when the number of dots constituting “standard size” is changed by the SSM control, it is necessary to recalculate all the character sizes.

The calculation formula for each character size is as follows.
(1) Standard size
Number of character dots (horizontal) = font size + character spacing
Number of character dots (vertical) = font size + line spacing
(2) Medium size
Number of character dots (horizontal) = font size / 2 + character spacing / 2
Number of character dots (vertical) = font size + line spacing
(3) Small size
Number of character dots (horizontal) = font size / 2 + character spacing / 2
Number of character dots (vertical) = font size / 2 + line spacing / 2
(4) Horizontal double size
Number of character dots (horizontal) = font size x 2 + character spacing x 2
Number of character dots (vertical) = font size + line spacing
(5) Vertical double size
Number of character dots (horizontal) = font size + character spacing
Number of character dots (vertical) = font size x 2 + line spacing x 2
(6) Vertical and horizontal double size
Number of character dots (horizontal) = font size x 2 + character spacing x 2
Number of character dots (vertical) = font size x 2 + line spacing x 2
When the character string is divided according to the character string display state, character repetition (RPC) control (control code for repeatedly displaying one character code following the control code for the number of times specified by the parameter) is performed on the character string. If it is used, care must be taken because it is necessary to add the character size × repetition count to the character string length. The displayed character size is a character code set before or after the RPC control code. Further, when the character string exceeds the display area by the RPC control, this division method is applied, and the character string exceeding the display area is set as a new character string.

  Data divided as a character string according to the above conditions is stored in a character string management table, and information on each character string is described. When the standard character size is considered in digital subtitles, the number of lines that can be displayed on the screen is about 14 lines. Also, assuming that one line of character blocks is a maximum of 3 blocks, the maximum character string is 42 columns. Therefore, the maximum number of character strings that can be handled by the character string reconstruction function is 50 in consideration of the reserve. FIG. 8A shows an example of a character string management table, and FIG. 8B shows an example of data described in each item of the management table.

Step S2: Character String Sorting Process In this process, the character strings divided according to the above conditions are rearranged in the order in which the start coordinates are close to the reference point. Further, after the character strings are sorted, it is determined whether the character string with the small character string flag is a ruby character string, or a prompt sound, a roaring sound, or a subscript character string. A character string deletion flag is attached to a character string determined to be a ruby character string, and it is excluded from the subsequent processing.

Note that the sound and roaring sound indicate small characters such as “yo”, “tsu”, and “ya” included in characters such as “a little” and “cabbage”. A subscript refers to a small number such as “CO ₂ ” or “H ₂ O” chemical formula.

  The determination of “ruby character string” determines whether the character string with the small character string flag is a ruby character string. The condition for determining that the character string is ruby is as follows. Only when all of the following conditions are satisfied, “ruby” is determined.

(Condition 1)
When the Y coordinate of the corresponding character string is a standard character size and is positioned one character higher than another character string or 0.5 characters lower (an image diagram is shown in FIG. 9).

(Condition 2)
The character string without the small character string flag is not adjacent to the X coordinate (start coordinate, end coordinate) of the character string (shown in the image diagram of FIG. 10).

  Since the small character string 1 satisfies the conditions 1 and 2, it is determined as a ruby character string. The small character string 2 satisfies the condition 1, but does not satisfy the condition 2, and thus is not determined as a ruby character string.

Step S3: Character block construction process The relevance of each character string arranged by the character string sorting process in step S2 is checked, and character strings determined to be relevant are combined to construct a character block.

  “Character string relevance check” is a process of checking relevance with each character string in order from the character string 1 in the character string management table. When the following relevance determination conditions are satisfied, it is determined as “relevant”. When it is determined that there is relevance, character string combining processing is performed.

  In the following judgment condition sentence, the character string for checking relevance is “A character string” and the character string to be checked is “B character string” in order to make it easy to understand the condition contents.

  (1) The Y coordinate difference between the A character string and the B character string is a standard character size and within one character. When the Y coordinate is a standard size and is separated from one character, the relevance check with the subsequent character string is not performed.

  (2) There is no terminal code in the A character string. If there is a terminal code, it is determined that the character block is a single character block, and the subsequent relevance check with the character string is not performed.

  (3) The color codes of the A character string and the B character string are compared, and the color codes are the same.

  (4) The X coordinate of the A character string and the B character string has an overlap with a standard character size of one character or more. The character overlap degree α is one or more characters, and is calculated using the following calculation formula.

<Calculation method of overlap condition α>
The X coordinate (X1) of the character string 1 is compared with the X coordinate (X2) of the character string 2, and the calculation formula is properly used according to the comparison result. In this calculation formula, the character string length of the character string 1 is L1, and the character string length of the character string 2 is L2.

When X1> X2
α = X2 + L2-X1
When X1 <X2
α = X1 + L1-X2
When X1 = X2
If L1 <L2, α = L1
If L1> L2, α = L2
Next, for character strings that are judged to be related by "Relevance check of character strings", character strings are combined to construct a character block. When combining character strings, the following conditions must be followed.

<String concatenation condition>
The Y coordinates of the character strings to be combined are compared, a character string having a small Y coordinate (close to 0) is used as the upper character string, and a character string having a large Y coordinate is combined with this character string. When the Y coordinate is the same, a character string having a small X coordinate (close to 0) is used as the upper character string, and a character string having a large X coordinate is combined with this character string. If the combined B character string has a terminal code, it is determined that the character block is complete. When the character block is completed, the A character string is not checked for relevance with the subsequent character string.

Step S4: Sort processing of character blocks When there are a plurality of character blocks constructed in step S3, the character blocks are sorted in order to determine the sending order of the character blocks. The conditions for sorting character blocks are as follows.

<Character block sorting conditions>
A character block having a small Y coordinate of the character block (close to 0) is set as a character block with a fast transmission order. When the Y coordinate is the same, priority is given to a character block with a small X coordinate (close to 0). The transmission order assigned to each character block is used as the storage order of character data when creating PES data.

  By the way, in the subtitle data for fixed receivers, the subtitle data expressing the prompting sound with a small size is converted into a character with a small character code of a 2-byte Kanji code. In addition, numbers and letters used as subscripts, prompt sounds, and stuttering are converted to medium size instead of standard size.

  According to the above processing, the fixed receiver subtitle data is divided according to conditions such as the operation position control code and the display state (coordinates) of the character string, and the divided character string is used as a reference point. Arrange the character blocks in the order of closeness, check the relevance of each character string, and combine the character strings determined to be related. If there are a plurality of constructed character blocks, the character blocks are sorted to make the character block having a small Y coordinate (close to 0) a character block with a fast sending order and having the same Y coordinate. In this case, the sending order can be automatically determined by giving priority to a character block having a small X coordinate (close to 0). Therefore, it is possible to automatically determine and edit the arrangement order and the display timing so that the subtitle display specification for the fixed receiver is a portable subtitle specification and the display order of each block is a meaningful word. .

  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 components disclosed in the embodiment. For example, some components may be deleted from all the components shown in the embodiment. Furthermore, constituent elements over different embodiments may be appropriately combined.

1 is a schematic configuration diagram showing an authoring device for creating a broadcast program of a terrestrial digital broadcasting system having the conversion function as one embodiment of a portable caption specification conversion device according to the present invention. The figure which shows a subtitle display image when the character string of HD subtitles is reconstructed into the character string of portable subtitles by the apparatus shown in FIG. The flowchart which shows the flow of a basic process of the conversion program which implement | achieves a character string reconstruction function in the apparatus shown in FIG. The figure which shows the example of an internal display area | region of a fixed receiver subtitle in the processing flow of the conversion program shown in FIG. The figure which shows the example of a division | segmentation by the operation position control code of the character string division | segmentation process in the processing flow of the conversion program shown in FIG. The figure which shows the example of a display in case the character code after the character code concerning the boundary value of a display area is made into another character string, when the divided character string shown in FIG. 5 exceeds a display area. The figure which shows the example of an initial value of the number of character dots of the character code which comprises the said character string. The figure which shows the character string management table for managing the said division | segmentation character string data, and its storage item. The image figure for demonstrating the 1st conditions which judge that a character string is ruby. The image figure for demonstrating the 2nd conditions which judge that a character string is ruby.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 11 ... Input interface part, 12 ... CPU (arithmetic processing unit), 13 ... Operation part, 14 ... ROM (read-only memory) 15 ... RAM (random access memory), 16 ... Output interface part.

Claims (16)

Provided for a fixed receiver a broadcast program that displays subtitles at a specified position on the screen in accordance with the video display, and used for a digital broadcast system that provides the broadcast programs for portable receivers. A portable caption specification conversion device for converting the data of the above into data for a portable receiver for which a caption display area is defined separately from a video display area,
A character string dividing means for recognizing and dividing a character string based on a predetermined recognition condition for the subtitle for the fixed receiver;
For each of the character strings divided by the character string dividing means, a character string sorting means for rearranging the start coordinates in order from the reference point,
Character block construction means for checking the relevance of each character string rearranged by the character string sorting means and combining character strings determined to be relevant to construct a character block;
A character block sorting means for determining a sending order of the character blocks based on a predetermined sorting condition when there are a plurality of character blocks constructed by the character block construction means;
A portable caption specification conversion device comprising:   The recognition condition is characterized in that a character code from a control code related to a character motion position added to subtitle data for the fixed receiver to a character string immediately before a control code related to the next character motion position is one character string. The portable caption specification conversion device according to claim 1.   The recognition condition is that the character string exceeds the caption display area when a character string divided by a control code related to the character motion position added to the caption data for the fixed receiver is arranged in the caption display area. 2. The portable caption specification conversion device according to claim 1, wherein the character code after the character code applied to the boundary value of the caption display area is set as another character string.   2. The relevance check according to claim 1, wherein when the coordinate interval between the character strings is within a reference range, it is determined that there is a relevance, and when it exceeds the reference range, it is determined that there is no relevance. Mobile caption specification conversion device.   In the relevance check, the first character string for checking relevance has no terminal code, the second character string to be checked has a terminal code, and the subsequent character string is adjacent to the first character string. The portable subtitle specification conversion apparatus according to claim 1, wherein if the character string is a character string to be determined, it is determined that there is a relevance, and if it is not, it is determined that there is no relevance.   The mobile subtitle specification conversion according to claim 1, wherein the relevance check determines that there is relevance when color codes between character strings added to the subtitle data for the fixed receiver are the same. apparatus.   The portable subtitle specification conversion apparatus according to claim 1, wherein the relevance check determines relevance from a degree of overlap between character strings.   The sorting condition is that a character block having a smaller Y coordinate in a direction orthogonal to the arrangement direction of the character strings is a character block with an earlier transmission order. If the Y coordinates are the same, the X coordinate in the arrangement direction of the character strings is 2. The portable subtitle specification conversion apparatus according to claim 1, wherein the smaller character block is prioritized. Provided for a fixed receiver a broadcast program that displays subtitles at a specified position on the screen in accordance with the video display, and used for a digital broadcast system that provides the broadcast programs for portable receivers. Is a portable caption specification conversion method for converting the data into caption data for a portable receiver in which a caption display area is defined separately from a video display area,
A character string dividing procedure for recognizing and dividing a character string based on predetermined recognition conditions for the subtitle for the fixed receiver;
For each of the character strings divided by the character string dividing procedure, a character string sorting procedure for rearranging the start coordinates in order from the reference point,
Character block construction procedure for checking the relevance of each character string rearranged by the character string sorting procedure and combining character strings determined to be relevant to construct a character block;
When there are a plurality of character blocks constructed by the character block construction procedure, a character block sorting procedure for determining the sending order of the character blocks based on a predetermined sorting condition;
A method for converting a portable subtitle specification, comprising:   The recognition condition is characterized in that a character code from a control code related to a character motion position added to subtitle data for the fixed receiver to a character string immediately before a control code related to the next character motion position is one character string. The portable subtitle specification conversion method according to claim 9.   The recognition condition is that the character string exceeds the caption display area when a character string divided by a control code related to the character motion position added to the caption data for the fixed receiver is arranged in the caption display area. 10. The portable caption specification conversion method according to claim 9, wherein the character code after the character code applied to the boundary value of the caption display area is set as another character string.   The relevancy check determines that there is relevance when the coordinate interval between the character strings is within a reference range, and determines that there is no relevance when the coordinate interval exceeds the reference range. Mobile subtitle specification conversion method.   In the relevance check, the first character string for checking relevance has no terminal code, the second character string to be checked has a terminal code, and the subsequent character string is adjacent to the first character string. 10. The portable caption specification conversion method according to claim 9, wherein if the character string is a character string to be determined, it is determined that there is a relevance, and if it is not, it is determined that there is no relevance.   The portable subtitle specification conversion according to claim 9, wherein the relevance check determines that there is relevancy when color codes between character strings added to the subtitle data for the fixed receiver are the same. Method.   10. The portable subtitle specification conversion method according to claim 9, wherein in the relevance check, the relevance is determined from the degree of overlap between character strings.   The sorting condition is that a character block having a smaller Y coordinate in a direction orthogonal to the arrangement direction of the character strings is a character block with an earlier transmission order. If the Y coordinates are the same, the X coordinate in the arrangement direction of the character strings is 10. The portable subtitle specification conversion method according to claim 9, wherein the smaller character block is prioritized.

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