AUSTRALIA Patents Act 1990 THOMSON LICENSING S.A. COMPLETE SPECIFICATION STANDARD PATENT Invention Title: Method for representing animated menu buttons The following statement is a full description of this invention including the best method of performing it known to us:- 2 Title Method for representing animated menu buttons 5 Field of the invention This invention relates to a method for adding animated menu buttons to an optical storage medium. 10 Background Today's optical storage media formats are capable of supporting visual menus, e.g. for content management or control functions. Applications of such visual menus are the selection of one out of multiple titles on the disc, the selection of a chapter within a 15 title, and others. From the user perspective, such menus consist of a number of buttons shown on the display. The user may navigate within the menu, e.g. by pushing the up, down, left and right buttons on his remote control to select a menu button, and may activate a menu button through some kind of "OK" button on the remote control. An indicator, usually a highlight or an arrow, may provide feedback to the user, showing 20 which button is currently selected or activated. A menu button may have one of the states "normal", "selected" or "activated". However, known DVD menus are rather limited concerning extra features, since they contain only static visual buttons. 25 Further, a subtitling specification contained in the document "ETS 300 743: Digital Video Broadcasting (DVB); Subtitling System" (DVB-ST), provided by the European Telecommunication Standardization Institute (ETSI), is known for embedding subtitles into video sequences. 30 Throughout this specification the word "comprise", or variations such as "comprises" or "comprising", will be understood to imply the inclusion of a stated element, integer or step, or group of elements, integers or steps, but not the exclusion of any other element, integer or step, or group of elements, integers or steps. 35 3 Any discussion of documents, acts, materials, devices, articles or the like which has been included in the present specification is not to be taken as an admission that any or all of these matters form part of the prior art base or were common general knowledge in the field relevant to the present invention as it existed before the priority date of each 5 claim of this application. Summary of the Invention In a first aspect, the invention provides computer readable storage medium having 10 stored thereon at least video data and a data segment representing control data for an on-screen menu for controlling the presentation of said video data, wherein the menu comprises menu buttons having one out of three states, the states being normal, selected or activated, and said control data comprise image data for representing said menu buttons in said states, wherein the image data that represent a particular menu button 15 state on a display comprise a sequence of pictures, and wherein said control data further comprise two region identifiers per button state, and a button image is addressable through at least one of said region identifiers, and wherein a value representing a rate for animating the sequence of pictures is stored on said storage medium, the rate for animating the sequence of pictures being relative to a video frame rate and being 20 different from the video frame rate, and wherein said relative rate at which the sequence of pictures is animated is an integer fraction of the video frame rate and is lower than the video frame rate. The present invention may be utilized to give more feedback to the user who operates a 25 menu related to an optical storage medium. The feedback comprises visually and/or aurally animated buttons. According to the invention, a menu button shown on a display may look different, depending on its state. The state may be "normal", "selected" or "activated", and for 30 each of these states the button may have different color or shape. Additionally, a sound or sound sequence may be attached to some or all menu buttons, depending on the buttons state. Examples for sounds are a click or a melody, or a speech sequence. The current invention provides a data structure by which those additional features can be described. 35 3a Advantageous embodiments of the invention are disclosed below. Brief description of the drawing 5 An exemplary embodiment of the invention is described with reference to the accompanying drawing in Fig.1, which shows an on-screen menu according to the invention, and a corresponding remote control. Detailed description of the invention 10 Fig. 1 shows a video screen I containing a menu that comprises buttons 2,3 and related text describing the buttons. When a user presses a button 5,6 on a remote control 4, the state of a button 2,3 may change, and also the representation of the button. In Fig.I one button 2 is selected, and thus looks different from the unselected buttons 3. When the 15 user e.g. presses the "right" button 6 on the remote control, another button 3 is selected being right from the currently selected button 2. When the user presses the "OK" button 5, the selected button is activated, and the function associated with the selected button is performed. The selected button 2 according to the invention is animated, e.g. has another color and another shape than an unselected button 3, and its color or shape may 20 change. Particularly, the button may also be replaced by a moving symbol, a moving cartoon or the like, depending on the state.
4 A preferred embodiment of the invention is based on the syntax and semantics of the subtitling specification contained in the document "ETS 300 743: Digital Video Broadcasting (DVB); Subtitling System" (DVB-ST), provided by the European Telecommunication Standardization Institute (ETSI). To provide enhanced capabilities 5 for menus relating to optical storage media, the page composition segment defined in DVB-ST is extended to describe animated menu buttons and to associate a sound or sound sequence to a button. The enhanced page composition segment is herein called a "menu page composition segment". 10 This invention, like DVB_ST, uses page composition segments to describe the position of one or more rectangular regions on the display, assuming that a region contains a representation of one button in a certain state, e.g. as pixel data or bitmap. Each button image is thus addressable through an identifier (ID), or "region_id". In this embodiment of the invention, backward compatibility is kept with DVB-ST by using an 15 associated segment type ID for the menu page composition segment. The menu page composition segment is defined as listed in Tab. 1. The "menu page composition segment" according to the invention may also replace the original page composition segment, e.g. in DVB-ST. A menu page composition 20 segment describes a menu and provides the necessary layout and timing information as well as additional control information. In one embodiment of the invention, being a simple case with static menus, each button is represented by e.g. three images. A first image represents the button in the "normal" 25 state, a second image represents the button in the "selected" state and a third image represents the button in the "activated" state. These images may be stored e.g. as bitmap files on the storage medium, and may be used to display the menu. In another embodiment, going beyond static menus, the menu page composition 30 segment also allows to describe animated buttons. In this case, the "normal" state and the "selected" state of a button are each represented through a series of images that are displayed, and may be e.g. cyclically repeated, on the screen to achieve the animation effect. Also for the "activated" state of a button an animation can be defined, but here it may be advantageous to display the animation phases only once, because the menu will 35 usually disappear or be modified after a button was activated.
5 For all button animations of a menu the menu author can specify an animation frame rate, defining how long each phase of an animation is displayed. Advantageously, the invention also provides the possibility to give aural feedback to 5 the user. If a button is either in the "selected" state or in the "activated" state, it may be assigned a sound identifier associated with a sound, which may be stored on the storage medium. The associated sound is played back when the button enters the respective button state. In one embodiment of the invention the associated sound is played back repeatedly, as long as the button is in the respective state. 10 The structure of the menu page composition segment and the semantics of the fields of the menu page composition segment are based on the structure and semantics given in DVB-ST, Section 7.2.1 "Page composition segment". Additional semantics definitions are used for an enhanced menu according to the invention. 15 Tab.1 shows the structure of a menu page composition segment according to the invention. Lines 1-8 are identical to the subtitle segment of the DVB-ST standard, giving the possibility to keep backward compatibility. The meaning of the fields shown in Tab.l is described in the following. The addressing of pixels is based on a coordinate 20 system whose origin is defined by the top-left corner of the associated video screen. Pixel addresses increase from left to right and from top to bottom. The dimensions of the associated video are defined as video-width * videoheight. Field Size Type I menu-page compositionsegment () { 2 sync byte 8 bslbf 3 segment type 8 bslbf 4 page id 16 bslbf 5 segment length 16 uimsbf 6 page time out 8 uimsbf 7 page version number 4 uimsbf 8 page state 2 bslbf 9 animation frame rate code 4 uimsbf 10 reserved 6 bslbf I I while (processed length < segment length) { 8 uimsbf 12 button number 16 uimsbf 13 button horizontal address 16 uimsbf 14 button vertical address 15 neighbour infoo 8 uimsbf 6 16 upper button number 8 uimsbf 17 lower button number 8 uimsbf 18 left button number 8 uimsbf 19 right button number 20 normal state infoo 8 uimsbf 21 start region idnormal 8 uimsbf 22 end regionidnormal 8 uimsbf 23 selected state info( 16 uimsbf 24 start region id selected 8 uimsbf 25 end region id selected 8 uimsbf 26 action state info( 27 start region id activated 8 uimsbf 28 end region id activated 8 uimsbf 29 button command info( 30 sound infoo 31 selected sound id 8 uimsbf 32 activated sound id 8 uimsbf 3 } 4 } Tab.1: Syntax of a menu page composition segment A segment is generally a data unit within the storage area. The segment type defines its 5 type. The menu page composition segment may be identified by setting e.g. segment type = Ox 18, since this value is not used in DVB-ST yet. The other fields in lines 2-8 of Tab.1 define the segment data set. The animationframeratecode field specifies the frame rate of animations in the case 10 of animated buttons being used. It applies to a range of regions specified by start region_id_xxx and end regionidxxx, with the "xxx" referring the state of a button. If a startregion id xxx and its corresponding endregionidxxx differ, they define a range of regions that shall be presented with this animation frame rate. For the normal and selected state, the presentation may be cyclically repeated; for the 15 "activated" state, the presentation shall be performed only once. When any start region_id_xxx is identical to the associated end regionidxxx, this designates a static or non-animated button state. Only the region designated by startregionidxxx is displayed, and for that button state the animationframeratecode shall have no meaning. 20 7 Tab.2 shows an exemplary list of animationframeratecodes. An animation may be visible at full video frame rate, e.g. 30 pictures per second, meaning that with each video frame another phase of the animation is displayed. It may also be sufficient to display only with every other video frame another phase of the animated button, thus 5 achieving another effect. Further, it is possible to define the frame rate to either be relative or absolute. Therefore the values of the animationframeratecode field have two different meanings, depending on if an associated video is present. In this case the animationframe_ratecode gives the animation frame rate relative to the video frame rate, otherwise it gives the absolute frame rate. 10 animationframe_ Relative animation Abs. animation rate code frame rate Frame rate Ox0 Reserved Reserved OxI Full video frame rate 30 Hz 0x2 2 of video frame rate 15 Hz 0x3 % of video frame rate 8 Hz 0x4 1/8 of video frame rate 4 Hz 0x5 1/16 of video frame rate 2 Hz 0x6 1/32 of video frame rate 1 Hz 0x7 - OxF reserved Reserved Tab.2: Example of animationframeratecode The buttonnumber field specifies a number that is an internal identifier for a button, 15 and is used for the fields defined below, e.g. the neighbour infoo field. Additionally, when button-number is entered directly through the user interface (UI), the associated button may be activated. Therefore a buttonnumber is unique within the menu. It may be e.g. a two-digit number in the range between 0 and 99. 20 Some fields used for menu animation according to the invention must be specified separately for each button. They are listed from line II of Tab.1, where a loop over all buttons starts. Each instance of the loop refers to one button. Implicitly, the button described by the first instance of the while-loop within menupagecompositionsegmento may be considered as "selected" when entering the 25 menu, and may be considered as "activated" if a page timeout for the menu is set and becomes active.
8 The button_ horizontaladdress field specifies the horizontal address of the top left pixel of the button. The specified horizontal position may be in between 0 and videowidth 1. Likewise, the buttonverticaladdress field specifies the vertical address of the top left 5 pixel of the button. The specified vertical position may be in between 0 and video_height-i. The upperbuttonnumber field specifies the button to be selected when the user navigates upward from the current button. The lowerbuttonnumber field specifies the 10 button to be selected when the user navigates downward from the current button. The leftbuttonnumber field specifies the button to be selected when the user navigates left from the current button. And the rightbuttonnumber field specifies the button to be selected when the user navigates right from the current button. 15 The start regionid_normal field specifies the ID of the first region to be presented for a button presentation in normal state, and the end region idnormal field specifies the ID of the last region to be presented for a button presentation in normal state. All regions with an ID between and including startregionidnormal and end regionidnormal shall exist; if start regionid_normal differs from 20 end region_id_normal, that range of regions shall be presented cyclically with the animation frame rate as defined by animationframeratecode. The start regionid_selected field specifies the ID of the first region to be presented for a button presentation in the selected state, and the endregion idselected field 25 specifies the ID of the last region to be presented for a button presentation in the selected state. All regions with IDs between start regionid_selected and end region_id_selected shall exist; if start-region idselected differs from end region_id_selected, that range of regions shall be presented cyclically with the animation frame rate described by animation frame rate code. 30 The start region idactivated field specifies the ID of the first region to be presented for a button presentation in activated state, and the endregion idactivated field specifies the ID of the last region to be presented for a button presentation in activated state. All regions with IDs between startregion idactivated and 35 end region id activated shall exist; if start region idactivated differs from 9 end region_id_activated, that range of regions shall be presented once with the animation frame rate described by animationframeratecode. The buttoncommandinfoo field serves as a container for commands associated with 5 this button, specifying the commands to be performed when the button is activated. Finally, the selectedsoundid field specifies the ID of the sound to be played when the button enters the "selected" state, and the activatedsound__id field specifies the ID of the sound to be played when the button enters the "activated" state. 10 The invention may be used particularly for menus stored on Blu-ray discs, but also DVD or other optical or non-optical high-capacity storage media.