Abstract:
A video application that is configured to prompt the display of images on a screen for viewing by a user. The screen includes a display layer that includes a display image having a representation of a sub-stream image. The user can select the representation of a sub-stream image to display a video stream.

Description:
CROSS-REFERENCE TO RELATED APPLICATION  
       [0001]     Priority is claimed under 35 U.S.C. § 119(e) to U.S. Provisional Patent Application No. 60/634,650, filed on Dec. 8, 2004, entitled “Simulation of Multiple DVD Video Streams in DVD-Video User Interfaces and Related Method,” by Jinha Kim, Leo Rios, and Jamil Khan Tajik, which application is incorporated by reference herein. 
     
    
     BACKGROUND OF THE INVENTION  
       [0002]     1. Field of the Invention  
         [0003]     The invention relates generally to the field of DVD-video streams. More specifically, the invention relates to the simulation of multiple, concurrent, DVD-video streams.  
         [0004]     2. Description of the Related Art  
         [0005]     DVD-video specifications, written and maintained by the DVD Forum (see http://www.dvdforum.org), set forth the technical capabilities of DVD-video applications, e.g., The Matrix (1999, WHV release). A DVD-video application must conform with these specifications in order for the DVD-video application to play on compliant, DVD-video players. Thus, the DVD-video specifications limit the range of display and interactivity options available for use on compliant, DVD-video players.  
         [0006]     One useful component of an engaging and an effective user interface in a DVD-video application is a thumbnail representation of a DVD-video stream (“video stream”), also referred to as a sub-stream image. A thumbnail representation is a small footprint video stream that is usually a repeating-loop excerpt of a full-size, unabridged video stream. In a graphical user interface (“GUI”), e.g., the graphical interface that is displayed on the monitor or television set that is coupled to the DVD player, a thumbnail representation can signify the option of a full video stream that is selectable and viewable by a user. The DVD-video specifications, however, do not contemplate or support the use of thumbnail representations. Accordingly, there is a need for the ability to display thumbnail-like representations of DVD-video streams, while still remaining compliant with the DVD-video specifications.  
         [0007]     Another useful component in a DVD-video application is the use of subtitles, also referred to as captions. However, the DVD-video specification does not support the use of subtitles simultaneously with other sub-stream images that are superimposed over a DVD-video stream. Thus, there is a need for the ability to display simultaneously subtitles as well as other sub-stream images on a DVD-video stream.  
       SUMMARY OF THE INVENTION  
       [0008]     The invention is a video application, apparatus, and method that facilitates the display of thumbnail-like representations of video streams, while still remaining compliant with the DVD-video specifications. The video application, apparatus, and method also facilitate the simultaneous display of subtitles as well as other sub-stream images on a DVD-video stream. An exemplary embodiment of the present invention is a video application that is configured to prompt the display of images on a screen for viewing by a user. The screen includes a display layer that includes a display image having a representation of a sub-stream image. The user can select the representation of a sub-stream image to display a video stream.  
         [0009]     In other, more detailed features of the invention, the display image includes a moving image stream, which can be a DVD image stream. Also, the user can choose to view a first version of the moving image stream that includes the representation of a sub-stream image or a second version of the moving image without the representation of a sub-stream image.  
         [0010]     In other, more detailed features of the invention, the display layer includes a subtitle. Also, the screen can further include a picture-mask layer that is located between the display layer and the user. The picture-mask layer can include a subtitle. In addition, the picture-mask layer can include a button, which includes a subtitle.  
         [0011]     In other, more detailed features of the invention, the screen further includes a highlight layer that is located between the picture-mask layer and the user. The highlight layer is configured to define an area that is included in the display layer or the picture-mask layer.  
         [0012]     In other, more detailed features of the invention, the picture-mask layer includes a mask image that is configured to cover the representation of a sub-stream image from viewing by the user or to highlight the representation of a sub-stream image for viewing by the user. Also, the user can select whether the mask image covers the representation of a sub-stream image. In addition, the picture-mask layer can further include a background image or more than one background image that can be cycled for viewing by the user.  
         [0013]     Another exemplary embodiment of the invention is an apparatus that is configured to display images for viewing by a user. The apparatus includes a display layer and a picture-mask layer that is located between the display layer and the user. The display layer includes a display image having a representation of a sub-stream image. The picture-mask layer includes a mask image that is configured to cover the representation of a sub-stream image. The user selects whether the mask image covers the representation of a sub-stream image. The user can select the representation of a sub-stream image to display a video stream.  
         [0014]     An exemplary method according to the invention is a method for displaying images on a screen for viewing by a user. The method includes providing a display layer and displaying a display image from the display layer. The display image includes a representation of a sub-stream image. The user can select the representation of a sub-stream image to display a video stream.  
         [0015]     Other features of the invention should become apparent from the following description of the preferred embodiments taken in conjunction with the accompanying drawings, which illustrate, by way of example, the principles of the invention.  
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0016]      FIG. 1  is a cross-sectional view of a DVD-image on a monitor screen.  
         [0017]      FIG. 2  is an elevational view of a display layer of a DVD-menu screen that includes sub-stream images.  
         [0018]      FIG. 3  is an elevational view of a picture-mask layer of a DVD-menu screen that includes mask layers.  
         [0019]      FIG. 4  is an elevational view a DVD-menu screen that includes both the display layer of  FIG. 2  and the picture-mask layer of  FIG. 3 .  
         [0020]      FIG. 5  is an elevational view of the DVD-menu screen of  FIG. 4  with one of the mask layers removed.  
         [0021]      FIG. 6  is an elevational view of the DVD-menu screen of  FIG. 4  with one of the mask layers removed.  
         [0022]      FIG. 7  is an elevational view of a moving, DVD-image stream that includes a sub-stream image in the display layer.  
         [0023]      FIG. 8  is an elevational view of a moving, DVD-image stream that includes a sub-picture in the picture-mask layer that covers the sub-stream image of  FIG. 7 .  
         [0024]      FIG. 9  is an elevational view of a moving, DVD-image stream without a sub-stream image.  
         [0025]      FIG. 10  is an elevational view of a moving, DVD-image stream that includes a sub-stream image in the display layer and a subtitle.  
         [0026]      FIG. 11  is an elevational view of a picture-mask layer that includes a subtitle, and is configured to overlay a display layer.  
         [0027]      FIG. 12  is an elevational view of a moving, DVD-image stream that includes a sub-stream image, and a subtitle that is incorporated into a button. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0028]      FIG. 1  is a cross-sectional, conceptual representation of a DVD-menu screen  10  that is presented on a monitor surface  12  according to one embodiment of the present invention. The menu screen is made up of three composite layers  14 - 18  that each have a different function. The first layer of the menu screen is the display layer  14 , which can include either a still picture (not shown) or a moving-picture, video stream (not shown), and accompanying audio.  
         [0029]     The menu screen  10  also includes a picture-mask layer  16 , which includes a black-and-white, or up to four color, background image (not shown). The background image is defined by eight bits of data made up of four bits of data for color, and four bits of data for contrast. Conceptually, the picture-mask layer overlays the display layer  14 , and thus, can block out images (not shown) in the display layer that lie below the picture-mask layer. Also, it is possible to cycle the picture-mask layer with different background images (not shown) so as present the illusion of animation in the picture-mask layer. The picture-mask layer includes sub-regions (not shown), or sub-pictures (not shown), that can be used to cover or hide portion of the display layer, e.g., simulated thumbnail representations (not shown) that are included in the display layer.  
         [0030]     The menu screen  10  also includes a highlight layer  18  that is used to define areas of the menu screen, in the display layer  14  and/or the picture-mask layer  16 , that have been selected or activated by the user, or by default. For example, portions of the highlight layer can be used to display an illuminated border (not shown) that surrounds selected images in the display layer and/or the picture-mask layer.  
         [0000]     Simulated Multi-Stream DVD Menu  
         [0031]     Referring to  FIG. 2 , one embodiment of the present invention presents a display image  20 , e.g., a title menu, that appears to be comprised of a still-image background  22 , a list of titles  24 , and one or more selectable, thumbnail representations of video-streams  26 , associated with each title. However, the thumbnail representations are an illusion achieved by using a single video stream that is included in the display layer  14  of the title menu. While the thumbnail representations are depicted as squares in  FIG. 2 , the thumbnail representations can be any shape. The single video stream presents a largely unchanging, background image that, because it does not, or largely does not, change, appears to be a still image despite being part of a stream of DVD-video images.  
         [0032]     The single video stream  20  also includes what appear to be smaller sub-streams  26  of different video images, but these smaller sub-streams are actually part of the single video stream included in the display layer  14 . Referring additionally to  FIG. 3 , the sub-streams are covered, or masked, by mask images  28  included in the picture-mask layer  16  that overlap one or more of the sub-stream images in the display layer. While the mask images are depicted as squares in  FIG. 3 , the mask images can be any shape. Thus, video images included in the sub-streams are playing below the masked images, but are not visible to the user, i.e., the viewer, as shown in  FIG. 4 .  
         [0033]     Using an interface device (not shown), e.g., a mouse or arrow keys included on the DVD player&#39;s remote control, the user can move between, highlight, and/or select one of the sub-stream images  26  by selecting a mask image  28 . Referring additionally to  FIGS. 5 and 6 , when a specific mask image is selected, the video sub-stream image underlying that mask image is unmasked, thus, revealing the sub-stream image playing in the display layer  14 . This gives the illusion that there is more than one sub-stream video image playing simultaneously in the picture-mask layer  16 , which is impossible under the current DVD specifications. In reality, there is only one video image  20  in the display layer, and one or more eight-bit data streams that define mask images in the picture-mask layer.  
         [0000]     Simulated “Activating” Selection Among Video Sub-Streams  
         [0034]     As shown in  FIGS. 5 and 6 , the illusion that the user is selecting among thumbnail representations of video-image sub-streams  26  that animate in response to user selection can be enhanced by allowing only one of the simulated thumbnail sub-streams to be visible to the user at a time. This is achieved by using mask image sub-pictures  28  in the picture-mask layer  16  to cover all but one of the image sub-streams at any given time. The image sub-streams are covered and uncovered as the user selects among the mask images.  
         [0000]     Simulated Multi-Stream Branching Video  
         [0035]     Referring additionally to  FIG. 7 , in another embodiment, a moving, DVD-video stream  30  displays what appear to be a selectable thumbnail representation  32  of another video stream at various points during the display of the video stream, not just in the menu screen  20 , to provide the user with the option of “jumping” or “branching” to different video streams. Again, this is an illusion achieved by displaying what appears to be smaller, sub-stream, video images in the overall video stream itself. In fact, the sub-stream images are included in the single video stream that is included in the display layer  14 . Referring additionally to  FIG. 8 , sub-pictures  34  in the picture-mask layer  16  can be used to highlight the sub-stream images, or cover the sub-stream images when they are not to be displayed to the user.  
         [0000]     Selection Between Normal Video Image And Video Image With Thumbnail Representations  
         [0036]     In another embodiment, the user can choose between watching the video stream  30  with thumbnail representations  32  of sub-stream video images (see  FIG. 7 ), or the video stream  36  without the thumbnail representations (see  FIG. 9 ). When the user chooses the video stream without thumbnail images, the user sees the normal, unaltered video stream. When the user chooses the video stream with thumbnail representations, the user either sees an entirely different video stream that incorporates the simulated thumbnail representations, or the user sees the normal video stream with specific subsections of the video stream substituted with alternate video streams that are used to simulate the thumbnail representations.  
         [0000]     Subtitles/Captioning  
         [0037]     As previously mentioned, one limitation associated with the simulated multi-stream branching video described above is the difficulty of concurrently using subtitles, or captions, while presenting the above simulated thumbnail video images. This difficulty comes from the fact that, according to the DVD specification, only one sub-picture stream, included in the picture-mask layer  16 , can be displayed simultaneously with the video stream  30 , included in the display layer  14 . Accordingly, this limitation prevents the simultaneous and separate display of both the video stream and two eight-bit mask layers, one eight-bit mask layer for the mask image(s)  32  and the other eight-bit mask layer for the subtitle  38  (see  FIG. 10 ). This means that the sub-picture stream in the picture-mask layer must either show both subtitles and the video sub-stream(s), i.e., the sub-picture stream includes both subtitles and the video sub-stream(s), the sub-picture stream includes only the subtitles and does not include the video sub-stream(s), or the sub-picture stream includes only the video sub-stream(s) and does not include subtitles at all. Thus, there is no mode of operation that allows the subtitles to be turned ON or OFF independent from the appearance of the video sub-stream(s).  
         [0038]     For example, referring to  FIG. 7 , during the playing of a DVD (not shown), a sub-stream image  32  could appear on the screen that, when selected, using a mouse or the DVD player&#39;s remote control, by the user, would stop the DVD image. The user would then view a supplemental feature (not shown) relating to what the user was watching when the sub-stream image was selected. When the supplemental feature is completed, the user then is returned to where the user left off in the DVD image  30 . This uses a feature in the DVD specification called “non-seamless branching,” and the sub-stream image appears on the screen courtesy of an eight-bit layer in the picture-mask layer  16 . Referring additionally to  FIG. 10 , the problem is that this feature cannot be used with two or more sub-stream images, e.g., a sub-stream image  32  and a subtitle  38 , or caption.  
         [0039]     Embodiments of the present invention work around the above limitation by using what is referred to as “seamless branching.” In these embodiments, the DVD (not shown) includes two versions of the portion of the video image  30  in which the sub-stream image  32 , or similar feature, e.g., subtitle  38 , is to appear. One version of the video image just includes the video image without the sub-stream image, as shown in  FIG. 9 . Referring additionally to  FIG. 7 , the second version includes the video image and the sub-stream image as part of the video image, i.e., the sub-stream image is part of the video stream. So, although the sub-stream image appears on the screen as if it is an eight-bit mask image included in the picture-mask layer  16 , the apparent sub-stream image is actually part of the video stream included in the display layer  14 . So, when the user selects the version of the video image that includes the apparent sub-stream image, the user is selecting another version of the DVD image, and not the same video image with an added eight-bit mask layer for the sub-stream image, e.g., a subtitle. Referring additionally to  FIG. 11 , this embodiment allows for the addition of subtitles that are included in the picture-mask layer, separate from the addition of another sub-stream image in the display layer.  
         [0000]     Branching Video with Subtitles Using Multiple Sub-Picture Streams  
         [0040]     In one embodiment, the above limitation regarding the addition of subtitles  38  to a DVD image  36  is overcome by the user being allowed to switch between two different eight-bit sub-picture streams  26  and  38  for a single video stream. In this embodiment, one eight-bit sub-picture stream includes only simulated video sub-stream selection highlights  32  (see  FIG. 7 ), the other sub-picture stream has simulated video sub-stream selection highlights and subtitles  38  (see  FIG. 10 ). When the user toggles between turning the subtitles ON or OFF, the DVD (not shown) switches between the two different sub-picture streams.  
         [0000]     Branching Video with Subtitles Using Button Highlight Management  
         [0041]     Referring additionally to  FIG. 12 , in another embodiment, the above limitation regarding the addition of subtitles  38  to a DVD image  30 ,  36  is overcome by selecting among multiple overlapping buttons  40  (one shown) in a single sub-picture stream. The DVD specifications provide for the display of buttons in the picture-mask layer  16 . In this embodiment, the subtitles are themselves buttons that when unselected are specified to be completely transparent. The button subtitles are only made visible when the subtitles are turned ON. When so selected, the pixels comprising the subtitles are changed from a color bit corresponding to “transparent” to a color bit corresponding to a visible color, such as white. This embodiment allows for the concurrent display of a simulated video sub-stream(s)  32  in the display layer  14  and button subtitles while retaining the ability to turn the subtitles ON and OFF by the user.  
         [0042]     Advantageously, the present invention differs from the prior art in that the user views a video image  20 ,  30  that includes a selectable, non-static, sub-stream video image  26 ,  32 . These sub-stream video images can be incorporated into menu screens  20  or into other moving-video images  30 . Thus, the present invention advantageously enables the simulation of multiple, concurrent video streams in support of DVD-video user interfaces, for example, the title menu and user-initiated video-branching, while remaining compliant with the DVD-video specifications.  
         [0043]     The foregoing detailed description of the present invention is provided for purposes of illustration, and it is not intended to be exhaustive or to limit the invention to the particular embodiments disclosed. The embodiments can provide different capabilities and benefits, depending on the configuration used to implement the key features of the invention. Accordingly, the scope of the invention is defined only by the following claims.