Abstract:
The claimed invention relates to a method of selecting a subtitle word displayed on a display by a digital versatile disc (DVD) system and thereafter displaying additional information corresponding to the selected subtitle word on a display. The method comprising the following steps: displaying subtitle data from a DVD on a display; selecting a subtitle data to be examined; converting the selected subtitle data into recognizable images; retrieving predetermined information related to the recognizable images; and displaying the predetermined information on the display. Operation of the DVD may thereafter be resumed. According to a first embodiment of the present invention, the DVD system is provided having an electronic dictionary function. The predetermined information is word definitions corresponding to words displayed in subtitles on the display. A user may select an unknown word, after which the definition of the unknown word is displayed on the display.

Description:
FIELD OF THE INVENTION  
         [0001]    The present invention relates to a method of selecting subtitle data displayed on a display by a digital versatile disc (DVD) system, and thereafter retrieving and displaying additional predetermined information corresponding to the selected subtitle data. Thus, a user may select a subtitle word appearing on the display, and the DVD system thereafter displays additional information based on the user&#39;s selection. In a first embodiment of the invention, a DVD system includes an electronic dictionary function. A user selects a subtitle word displayed on the display. Thereafter, a definition of the selected word is displayed on the display.  
         DESCRIPTION OF THE PRIOR ART  
         [0002]    A conventional DVD system is operable to access and receive information stored upon a laser-readable disc of storage media (DVD disc). The DVD disc stores compressed video, audio, and subtitle data. This data is stored on the DVD disc in accordance with a standardized format. The DVD system reads the data from the DVD disc, and stores the data in a buffer memory for subsequent retrieval. In addition, the DVD system can perform interactive playback in which a user can communicate with the system during playback, and provide additional instructions.  
           [0003]    Subtitle data, called sub picture units (SPU), is actually displayed in the format of a graphic image, not as text data. SPU data can comprise a word, words or sentences, referred to as an ‘SPU packet’. When the DVD disc is produced, instead of imprinting a letter or word in a text format, subtitle images are comprised of the same data as other visual images on the disc. SPU data is therefore ‘burned’ as a graphic image onto the DVD disc at the appropriate place, so that it is synchronized with the audio being spoken and images displayed. Therefore, if a stream of video images are displayed on the display, there are pre-designated places for locating SPU data.  
           [0004]    As best shown in FIG. 1, a conventional DVD system  2  comprises the DVD player  4 , an input device  6 , and a display  8 . Audio data may be output to an external audio apparatus  9 , often associated with the display  8 . The display  8  may be a television, monitor, screen or any other known display. The input device  8  may be an infrared remote control, a mouse, a tablet, a track ball, a keyboard, or the like.  
           [0005]    Some of the operational components of a conventional DVD system  2  are best shown in FIG. 2. The conventional DVD system  2  comprises a central processor unit (CPU)  11  for executing programs recorded on a ROM or a RAM, a DVD driving unit  12 , a video/audio signal processing unit  13 , a caption display unit  14 , a memory  15  for storing caption data and sync data, an image overlapping unit  16  for displaying a portion of the caption data on the display  8 , an on screen display (OSD) output unit  23 , and an input device  6  for inputting user commands. A conventional DVD system  2  has a caption-based display search function, as well as a repeat function.  
           [0006]    Operation of the DVD system  2 , or DVD reproduction, may be initiated when a user inserts a DVD disc into the DVD driving unit  12 , and inputs reproduction instructions using the input device  6 . The CPU  11  controls the DVD driving unit  12  to read SPU data (i.e. caption data), as well as video and audio data (i.e. sync data) on the disc. Thereafter, the CPU  11  reconstructs the caption data and the sync data into pairs of caption character strings and pairs of sync data and stores them in the memory  15 . Specifically, the CPU  11  sends the data to a decoding chip set (DSC), where the data is decompressed and decoded. Thus, the audio, video, and subtitle data are processed as specific caption character strings.  
           [0007]    Once DVD reproduction is initiated, the CPU  11  retrieves the appropriate caption character strings and sync data from the memory  15 . A particular scene or image may include a series of caption character strings. The CPU  11  sends appropriate pairs of sync data to the image overlapping unit  16 , thereby causing the sync data to be overlapped on the display  8  being reproduced. Subtitle data, or caption character strings, are also retrieved from the memory  15 , and displayed on the display  8  by transmitting caption data to the caption display unit  14 .  
           [0008]    The caption character strings, as well as the sync data, are consecutively stored in the memory  15 , and assigned a particular frame number corresponding to each frame. Thus, the CPU  11  is able to determine which frame, and corresponding frame number, is being displayed. In this way, the CPU  11  is able to determine which new caption character strings should be retrieved from the memory  15  based on the frame being displayed on the display  8 . The CPU  11  controls the caption displaying unit  14  to delete the previous caption character string, and then retrieves the next appropriate caption character string from the memory  15  once again to be displayed. Thus, the previous caption character string is replaced by a new caption character string.  
           [0009]    In order to display the subtitle data in the appropriate position on the display, the subtitle data, or SPU packets, are decoded by a DCS. This DSC contains a series of code, commonly referred to as the SPU address, which allows the SPU packets to be properly displayed on the display  8 . The SPU address includes a particular micro-code, which directs the SPU packets to be displayed at a designated position on the display  8  following the decoding process by the DCS. This position is predetermined by the manufacturer, and controlled by the micro-code in the SPU address. In addition, the DCS is able to determine when the SPU packets are to be decoded and displayed based on specific parameters, which are also predetermined by the manufacturer. These parameters (i.e., defining the starting and stopping point for SPU packets) are known as the run length code. Therefore, the positioning of the subtitles on the display  8 , as well as the presence of the subtitles on the display  8  with respect to frames, is defined by the micro-code and the run length code.  
           [0010]    As images are being displayed, the CPU  11  simultaneously monitors for additional instructions input by the user through the input device  6 . For example, the user may operate a display button on the input device, associated with the OSD output unit  23 , which causes a menu to be displayed on the display  8 . The user may then make additional selections from the displayed menu, as known in the art. Directional keys on an input device  6 , along with an enter function actuating the selection, are also known in the art. The CPU  11  is able to determine a designated position for DVD reproduction based on the user&#39;s selection. The CPU  11  controls the DVD driving unit  12  to change the reproduction position to the designated position.  
           [0011]    Thus, the user is able to provide some instruction as to DVD reproduction, such as selecting a particular scene, or repeating a particular series of frames. However, if a DVD disc contains subtitle data, the user may desire additional information corresponding to the subtitles being displayed. For example, many users use DVD discs as study tools, wherein subtitles are displayed on the display  8 . When the user encounters an unknown word in the subtitles, the user is required to inconveniently look up the unknown word in a separate dictionary. As a result, it is difficult for the user to fully understand the situation presented on the display  8 , or master the linguistic nuances of a word appearing on the display  8 . The user generally must look away from the display  8  and look up the unknown words in the dictionary, thus being distracted from the images being displayed.  
         SUMMARY OF THE INVENTION  
         [0012]    According to the present invention, a user may select a subtitle word displayed on a display of a DVD system  2 , and thereafter receive additional information also displayed on the display  8  that corresponds to the selected word.  
           [0013]    A method for achieving the above objective includes the following steps: displaying subtitle data from a DVD on a display; selecting subtitle data to be examined; converting the selected subtitle data into recognizable images; retrieving predetermined information corresponding to the recognizable images; and displaying the predetermined information on the display.  
           [0014]    The user selects a caption character string (i.e. a word) from the displayed subtitles by moving a cursor, which is automatically generated at a position of the first word in a displayed sentence, using directional keys associated with an input device  6 . The user may move the cursor onto any desired word in the displayed sentence by using the direction keys, and thereafter select the word using the input device  6 . After the user makes a word selection, predetermined information that corresponds to the selected word is retrieved from a database, and displayed on the display  8 . The user may then resume operation of the DVD when desired.  
           [0015]    The predetermined information may be any additional information corresponding to the selected word, and may be stored in a database or memory. The user&#39;s selection of the word triggers the display of the corresponding predetermined information, which is retrieved from a database  22  by the CPU  11 . The CPU  11  controls the OSD output unit  23 , which causes the predetermined information to be displayed on the display  8 . The OSD output unit  23  causes the predetermined information to be displayed on an on screen display, as is known in the art.  
           [0016]    According to a first embodiment of the present invention, a DVD system has an electronic dictionary function, wherein the predetermined information corresponds to definitions of words displayed in subtitles on the display  8 . The user may select an unknown word, while images on the display  8  are paused. Following the user&#39;s selection, the definition of the unknown word is displayed on the display  8 . Specifically, the claimed method includes the following steps: displaying subtitle data from a DVD on a display; selecting subtitle data to be examined and pausing operation of the DVD during the examination; converting the selected subtitle data into recognizable images; recognizing words formed by the recognizable images, retrieving a definition of a recognized word from a dictionary database, displaying the definition on the display; and resuming DVD operation. The subtitle data may be in SPU format, and the recognizable images may be formatted in ASCII codes. Thus, ASCII codes are retrieved that correspond to subtitle data in SPU format.  
           [0017]    According to the first embodiment of the claimed invention, words displayed on a display  8  in the form of subtitles may be defined by looking up the words in an electronic dictionary database  22 . The electronic dictionary function may be performed even while the section repetition is made. As a result, a comprehension understanding of words may be learned, as well as an understanding of situations and the linguistic nuance of the words.  
           [0018]    In second embodiment of the claimed invention, the user selects the dictionary function by using the input device  8 . The input device  8  may have a specific button for initiating the dictionary function, or the dictionary function may be selected from a menu displayed on the display  8  by the OSD output unit  23 . The user then spells a word using character or letter keys on the input device  8 . The CPU  11  then retrieves the predetermined information corresponding to the input data, which is formatted in ASCII code. Therefore, the CPU  11  retrieves the predetermined information related to the ASCII codes input by the user using the input device  8 . In this way, the dictionary function operates as a simply dictionary.  
           [0019]    Some elements of a DVD system  2  of the present invention correspond to elements in a conventional DVD system  2 , as shown in FIGS. 1 and 2. Corresponding elements explained above will not be described hereafter. A DVD system according to the present invention, and a conventional DVD system, both may include a CPU  11  for executing programs, a DVD driving unit  12 , a video/audio signal processing unit  13 , a caption display unit  14 , a memory  15 , an image overlapping unit  16 , an OSD output unit  23 , and an input device  6 .  
           [0020]    In addition, the claimed invention provides for a character code converter  21  for converting subtitle data into recognizable images, as well as a database for predetermined information  22 , such as an electronic dictionary database. The character code converter  21  converts subtitle data formatted in SPU format to recognizable images formatted in ASCII codes. Predetermined information, corresponding to the ASCII codes, is then retrieved from database  22  and displayed on the display  8  by the OSD output unit  23 . 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0021]    [0021]FIG. 1 is a drawing of a DVD system including a DVD player, a display, an audio apparatus, and an input device;  
         [0022]    [0022]FIG. 2 is a schematic diagram illustrating various components of a conventional DVD system;  
         [0023]    [0023]FIG. 3 is a schematic diagram illustrating various components of a DVD system according to the present invention;  
         [0024]    [0024]FIG. 4 is a flowchart illustrating the steps of selecting a subtitle word displayed on a display by a DVD system and thereafter displaying predetermined information relating to the selected word; and  
         [0025]    [0025]FIG. 5 is a flowchart illustrating the character recognition algorithm according to the present invention. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0026]    Operational components of a DVD system according to a first embodiment of the claimed invention are best shown in FIG. 3. According to the present invention, the DVD system includes: a CPU  11 ; a DVD driving unit  12 ; a video/audio signal processing unit  13 ; a caption display unit  14 ; a memory  15 ; an image overlapping unit  16 ; an input device  6 ; a code character converter  21 ; an electronic dictionary database  22 ; and an OSD output unit  23 . As in the conventional DVD system  2 , the DVD system according to the present invention is operably associated with a display  8  and an audio apparatus  9 . As noted above, the display  8  may be a television, monitor, screen or any other known display. Similarly, the input device  6  may be an infrared remote control, a mouse, a tablet, a track ball, a keyboard, or the like.  
         [0027]    Note that FIG. 3 shows a first embodiment of the present invention, wherein the system includes an electronic dictionary function. However, the claimed invention provides for retrieval of any predetermined information from a database or memory, and is not limited to retrieval of dictionary definitions. For example, selection of a letter, character, word, number or combination thereof displayed in the subtitles on the display may trigger the retrieval of encyclopedic information, footnote information, mathematical equations, or any other desired predetermined information related to the selected subtitle data. Such predetermined information may be stored in a database corresponding to the electronic dictionary database. However, for purposes of explanation, the claimed invention will be explained according to the first embodiment, wherein the predetermined information is dictionary definitions of words displayed in subtitles on the display.  
         [0028]    The disclosed invention is designed to work with conventional DVD systems  2 . As such, many of the components mentioned above are known in the art, and will not be explained hereafter. As shown in FIG. 4, the user may select the electronic dictionary function using the input device  6  (step S 70 ). Preferably, this selection causes a cursor to be automatically generated at a position of the first word in a displayed sentence of subtitles. However, the selection may also cause a menu to be displayed by the OSD output unit  23 , which includes a dictionary function that may then be selected using the input device  6 . As explained above, the subtitle data consists of caption character strings, and is preferably formatted in SPU format. The user may select any word from the displayed subtitles by moving the cursor onto the desired word using directional keys and an enter button on the input device  6 , as commonly known in the art. The cursor automatically moves from word to word with a sentence or phase being displayed on the display  8 .  
         [0029]    As best shown in FIG. 4, a user selects a subtitle word displayed on a display by a DVD system, and thereafter additional predetermined information is displayed. Specifically, the user selects the electronic dictionary function using the input device  6  when the DVD system is displaying subtitle data on the display (step S 70 ). Then, the CPU  11  controls the DVD driving unit  12 , video/audio signal-processing unit  13 , caption display unit  14 , and image overlapping unit  16 , causing DVD reproduction to be paused (step S 71 ). In addition, audio output to the audio apparatus  9  may is paused.  
         [0030]    Next, the CPU  11  scans a particular area on the display  8  that contains the subtitles for subtitle data (step S 72 ). (The scanning process is described below). The particular area containing subtitles is defined by micro-code and run-length code, as explained above. Thus, the CPU  11  scans only those parameters of data defined by the micro-code and run-length code, and identifies the subtitle data therein. The CPU  11  then converts the subtitle data into recognizable images during the scanning process, or character recognition algorithm, explained below (step S 73 ). The subtitle data are preferably formatted in SPU format. The recognizable images are preferably formatted in ASCII codes. The recognizable images may be letters, characters, numbers, or combinations thereof. In the preferred embodiment, the recognizable images are letters, and may be recognized in plurality as words.  
         [0031]    After the CPU  11  has deciphered the subtitle data as recognizable images, a cursor is automatically generated at the first word appearing in the subtitles being displayed on the display  8  (step S 74 ). The cursor is controlled by the OSD outputting unit  23 , as known in the art. The user may move from word to word using the directional keys on the input device  6 , and select a word using the enter button on the input device  6  (step S 75 ). After making a selection, the CPU  11  retrieves predetermined information corresponding to the selected word, which has been deciphered as a recognizable image (step S 76 ). The predetermined information is then displayed on the display  8  (step S 77 ). Thereafter, the user may resume DVD operation, or select another word (step S 78 ). If another word is selected by the user, the predetermined information corresponding to the first word selected is automatically removed from the display, and the new predetermined information corresponding to the next word selected by the user is displayed on the display.  
         [0032]    [0032]FIG. 5 is a flowchart illustrating the scanning process. In order to identify subtitle data displayed in subtitles on the display  8 , the CPU  11  scans data corresponding to a particular area on the display  8 . Specifically, the CPU  11  scans only the subtitle data that is defined by the micro-code and run-length code parameters, as noted above. Within these parameters, the subtitle data are bit map images that are displayed on the display  8  by a plurality of activated pixels (step S 81 ). The CPU  11  scans this subtitle data to determine which of the pixels are activated on the display  8 . The subtitle data forms a rectangular area defined by run length code on the display  8 . This rectangular area is selectively scanned, in a predetermined sequence (step S 82 ). Specifically, the pixel positioned at a corner in the upper left corner of the rectangular area is scanned first. Thereafter, pixels horizontally, vertically, and diagonally adjacent are scanned sequentially and simultaneously from top left to bottom right. In this way, all pixels in the rectangular area are scanned, with the pixel in the upper left corner, relative to the user&#39;s view of the display  8 , being scanned first, and the pixel at the opposite lower corner being scanned last.  
         [0033]    The CPU  11  identifies all activated pixels in the selected rectangular area (step S 83 ), and thereafter initiates a character recognition algorithm. Specifically, the scanned data is compared to preprogrammed recognizable images (i.e. letters defined by a particular font, size, etc., as known in the art). In this way, the CPU  11  identifies and correlates the activated pixels to recognizable images being displayed on the display  8  (step S 84 ). Similarly, a plurality of such letters is further recognized as a word. The recognizable images are preferably formatted in ASCII code, in which case the CPU  11  directs the character code converter  23  to convert the subtitle data from SPU format to ASCII code. After converting the activated pixels into recognizable images, the CPU  11  retrieves predetermined information corresponding to the recognizable images selected by the user (step S 85 ). The predetermined information may be stored in a database, and retrieved therefrom by the CPU  11 . This predetermined information is then displayed on the display  8  (step S 86 ).  
         [0034]    In a conventional DVD, the specification is primarily composed of a video data region, an audio data region, and an SPU data region. The SPU data region is largely composed of a SPUH (sub-picture unit header), PXD (pixel data), and a SP-DCSQT (subpicture display control sequence table). According to the second embodiment of the present invention, the ASCII code data that corresponds to the PXD are inserted into the SPU data region. The CPU  11  reads this inserted ASCII code data, instead of first reading the SPU data (or subtitle data). Therefore, no subsequent conversion into ASCII code (or other recognizable image) is necessary. Therefore, the CPU  11  initially scans for subtitle data, and may automatically correspond any such subtitle data to respective ASCII codes, which are already inserted into the CPU  11 . Thus, the CPU  11  may quickly display predetermined information from the database corresponding to the ASCII codes.  
         [0035]    As noted above, certain aspects of the claimed invention have been explained according to a first embodiment having an electronic dictionary function. However, it will be apparent to one of ordinary skill in art that various modifications and variations can be made in construction or configuration of the present invention without departing from the scope or spirit of the invention. The character recognition algorithm may be applied to numerous applications and functions, given any additional predetermined information may be stored in the database. Thus, it is intended that the present invention cover the medications and variations of the invention, provided they come within the scope of the following claims and their equivalents.