METHOD OF AND APPARATUS FOR DISPLAYING INFORMATION UNITS

Abstract: The invention relates to a method of and apparatus for displaying an electronic program guide. Program data, e.g. titles, are displayed in a detailed view along one or more coordinate axes, e.g. representing TV channels and broadcast times. Additionally, an area of the screen shows a zoomed-out view comprising reduced representations of the programs. It is indicated which reduced representations correspond to the programs displayed in the detailed view. The user is allowed to scroll through the information in both the detailed and the zoomed-out view.

Description: Method of and apparatus for displaying information units. FIELD OF THE INVENTION The invention relates to a method of displaying information units, e.g. receivable programs in an electronic program guide (EPG), comprising the steps of: obtaining attribute values relating to attributes of said information units, e.g. channel name, broadcast time, program category, and program title of said receivable programs, defining at least one coordinate axis representing one of said attributes, e.g. broadcast time or channel, relating a coordinate position along said coordinate axis to each of the information units in accordance with their attribute values, displaying an attribute value, e.g. program title, for at least some of the information units related to a coordinate position on a visible part of the coordinate axis. The invention further relates to apparatus for receiving a plurality of programs, comprising: - decoding means for receiving and decoding attribute values relating to attributes of said programs (e.g. channel number, broadcast time, program category, or program title), display means for relating a coordinate position along a coordinate axis to each of the programs in accordance with their attribute values, the coordinate axis representing one of said attributes, e.g. time or channel, and displaying an attribute value, e.g. program title, for at least some of the programs related to a coordinate position on a visible part of said coordinate axis. The invention further relates to a data carrier and an information processing device. BACKGROUND OF THE INVENTION Such a method and apparatus are well known. For example, known television receivers and set-top boxes comprise an electronic program guide (EPG) which is capable of receiving and decoding program data, such as channel number and broadcast time, relating to programs which will be transmitted in the near future. Generally, such an EPG shows a list of program titles and the clock-times, indicating at what time and by which channel the programs will be transmitted. For example, US 5,808,608 discloses a television receiver capable of showing said data in a so called grid TV guide, comprising an array of cells, each cell containing program data relating to a distinct program. A disadvantage of the known method and apparatus is that a lot of information is presented, particularly in a textual format, which makes it hard for a user to get a quick overview of programs which might be of interest to him. Generally, there is a large number of receivable channels and a large number of programs scheduled for each of the receivable channels. With the known method and apparatus only a small part of the available information can be displayed, and other parts have to be selected by scrolling through the information. This is inconvenient and time consuming. OBJECT AND SUMMARY OF THE INVENTION It is an object of the invention to provide a method and apparatus of the type defined in the opening paragraph which enables a user to easily get an overview of the available information units. To that end, the method according to the invention is characterized in that the method further comprises a step of displaying reduced representations, e.g. dots or lines, of attribute values of information units related to coordinate positions of a further part of the coordinate axis, which further part includes said visible part and is substantially larger than said visible part. In this way it is achieved that, in addition to a detailed view of a small part of the available information units, a user has an overview of a larger part of the information units without being bothered by the details of the information units of the larger part. The user is thus given a detailed zoomed-in view of the information, similar to the prior-art method, and a zoomed-out view of the same information, which may show the same information at a reduced seale or by means of abstract representations, e.g. dots representing each information unit. Certain parameters of the abstract representations, e.g. size or color, may correspond to different attribute values of the information units, e.g. duration, genre of receivable programs. Both views can be presented simultaneously or one at a time. When the views are presented one at a time, several transitions are possible: e.g. simply replacing one view with the other, zooming in and out, blending, sliding, etc. The zoomed-out view may represent a considerable part of the total information space, and preferably it represents the whole information space so that the user has a complete overview at a glance. The zoomed-out view preferably comprises an indication which part of the view corresponds to the zoomed-in view or a selected unit within the zoomed-in view, e.g. by highlighting or bordering the part corresponding to the zoomed-in view. This indication can be used to change the part of the information presented by the zoomed-in view. Navigating in the zoomed-in view, automatically means navigating in the zoomed-out view. A position feedback (e.g. a highlight) can be moved around in the zoomed-in view. When doing so a second position feedback (e.g. another highlight) moves around in the zoomed-out view, conform the movement of the first position feedback. In this manner the two views are directly linked. The other way around could also be possible: Navigating in the zoomed-out view, automatically means navigating in the zoomed-in view. A position feedback (e.g. a highlight) can be moved around in the zoomed-out view. When doing so a second position feedback (e.g. another highlight) moves around in the zoomed-in view, in conformity with the movement of the first position feedback. In this manner the two views are directly linked as well. When the two views are not presented simultaneously the same principle can be applied, so the two views are still directly linked. The difference is that only one position feedback will be visible, but moving the visible position feedback, which is in the zoomed-in view or the zoomed-out view, also results in moving the non-visible feedback, which is outside the zoomed-in view or the zoomed-in view, in conformity with the movement of the first, visible position feedback. When switching between the views the two position feedbacks will point at the same position, helping the user not to get lost in the content space. The position feedback can either move incrementally, e.g. from item to item or on some other grid, or move in a continuous manner, e.g. like a mouse pointer. In this way the method according to the invention helps both to know one's position in the information space at any time and to easily find information of interest in that information space. The method according to the invention is particularly advantageous for displaying filtered information units. A disadvantage of the known methods is that filtering the information yields empty spaces within the displayed information. For example, in a grid or 'matrix' EPG, one may filter only programs belonging to a certain genre. This will result in the matrix being filled only partly, having empty spaces at positions which correspond to programs not belonging to the requested genre. A user might lose his way if such an empty space is larger than the space that can be perceived (e.g. larger than the available screen space). An advantageous embodiment of the method according to the invention is characterized in that such rejected programs are represented in the zoomed-out view by, for example, faintly colored or semi-transparent representations. Alternatively, the rejected programs are represented by means of empty spaces in the zoomed-out view as well. Since the zoomed-out view represents a large part of the information space, the empty space does not cause the user to lose his way. On the contrary, the user is enabled to quickly locate clusters of information units which satisfy the requirements. Usability may be further enhanced by further reducing groups of such faint or transparent representations relating to rejected information units so as to allocate more space to reduced representations relating to selected information units. In this way the available screen space can be utilized more efficiently. This can be accomplished by applying a non-linear coordinate distribution in the zoomed-out view, i.e. a small zoom-factor where rejected units are located and a larger zoom-factor where selected units are located. BRIEF DESCRIPTION OF THE DRAWINGS These and other aspects of the invention are apparent from and will be elucidated, by way of a non-limitative example, with reference to the embodiment(s) described hereinafter. In the drawings, Figure 1 shows a diagram of a television receiver as an embodiment of the apparatus according to the invention, Figure 2 shows an example of a screen representation of an EPG in accordance with an embodiment of the method according to the invention. DESCRIPTION OF EMBODIMENTS Figure 1 shows a block diagram of a digital television receiver as an embodiment of the apparatus according to the invention. Digital broadcast streams, modulated upon radio frequency (RF) signals, are received from the ether by an antenna 1 or, alternatively, from a cable network. The broadcast streams may be formatted, for example, in accordance with the Digital Video Broadcasting (DVB) standard. A tuner 2 comprises a standard analog RF receiving device which is capable of receiving said RF signals and selecting one of them to be output to a demodulator 3. Which signal is selected by the tuner 2 is dependent upon control data received from a central processing unit (CPU) 5. A demodulator 3 converts the analog signal into a digital packet stream, based on control signals received from the CPU 5. This packet stream is then output to a demultiplexer 4, which selects packets belonging to a particular program in accordance with control data received from the CPU 5, and decomposes the packet stream into elementary video, audio or data streams. In addition to broadcast signals, the television receiver may be adapted to receive signals from other sources too, for example, from a (digital) video recorder or DVD, from Internet, or from a digital subscriber line. Programs and program attributes need not be obtained from the same source. For example, attributes and attribute values relating to broadcast programs may be obtained from an internet site. A video processor 8 decodes the video stream received from the demultiplexer 4 or from the CPU 5. Decoded video data is then transmitted to a display screen 9. An audio processor 6 decodes the audio stream received from the demultiplexer 4. Decoded audio data is then transmitted to a loudspeaker system 7. The demultiplexer 4 outputs the elementary data stream to the CPU 5. The elementary data stream has two types of data: control data and content data. Content refers to, for example, interactive programs; control refers to tables in the multiplex, which specify matters like the structure of the multiplex, the (RF) frequencies at which the channels are modulated, and the addresses at which the various content components and the (other) tables in the multiplex can be found. The CPU 5 comprises one or more microprocessors capable of executing program instructions stored in a read-only memory (ROM) 12. These program instructions comprise parts of software modules including, inter alia, a command module 13, and an EPG module 14. Data processed by said software modules, e.g. DVB-SI data and user profile information, may be stored in a non-volatile memory 11. The command module 13 is capable of controlling functions of the TV-set, like tuning and demultiplexing selection, and transmitting data to the video processor 8 to be presented on the screen 9. A user command unit 10 receives user commands, e.g. through a remote control (not shown), and transmits them to the command module 13 to be processed. For example, when the user enters a channel number, the command module 13 controls the tuner 2 and the demultiplexer 4 to select the corresponding broadcast stream and data packets therein, and sends graphical data to the video processor 8 to present feedback on the screen 9, e.g. the preset number, the channel name being displayed for a few seconds. The EPG module 14 interprets the DVB-SI data received from the demultiplexer 4 to collect information about the channels ('services' in DVB terminology) available in the received broadcast streams and about the programs ('events' in DVB terminology) scheduled for those channels. Figure 2 shows an example of a screen representation of an EPG in accordance with an embodiment of the method according to the invention. After a suitable user command, a time axis 26 is displayed, along with a number of clock times, in the example ranging from 19:00 to 21:00. Below the time axis 26, a detailed 'zoomed-in' view 25 is provided, including program titles of programs which are broadcast at the indicated clock times by the TV channels which are shown on the left side of the view 25. Instead of, or in addition to, program titles, other attribute values may be presented, such as the program genre or a graphical pictogram representing a scene from the program. A highlight 27 indicates that one of the programs is a selected one. The selected program can be programmed for recording or reminding, or additional information may be requested for it. In the detailed view 25, only five channels and five half-hours are shown. The command module 13 allows the user to scroll the view 25 so as so reveal program data of other channels and other times of the day or week. The displayed information is only a small part of the total information space, so the user may easily lose his way. Furthermore, the programs may be filtered in accordance with a user profile, yielding empty spaces in the view 25. It may occur that the view 25 does not show any program data at all since all programs corresponding to the channels and clock times on screen are rejected by the user profile. In such a case, the user is even more likely to go astray. These problems are solved by the method according to the invention by the provision of a zoomed- out view 21 which, in the example, is located at the top of the screen. It shows a considerably larger part of the information space, e.g. the filtered programs of a complete day or week and for all receivable channels. The programs are represented by reduced representations, such as the dots in the example, instead of program names. Alternatively, the programs could be represented by small lines, the length of which corresponds to the program's duration. The color of the reduced representations could reflect the program's category or genre. An area 23 in the view 21 is highlighted to indicate that this area 23 corresponds to the detailed view 25. Also, one of the reduced representations is made somewhat larger than the other ones, to indicate that it corresponds to the selected program 27. In this way it is achieved that the user is given both a global overview of a large part of the information space and a detailed view of a small part of the information space. Furthermore, the relation between the two views is always clear because of the visible indications 23 and 24 in the zoomed-out view 21. Hence, the user is very unlikely to lose his way, even if the detailed view 25 does not show any program data due to the filtering effect of a user profile. The user is enabled to reposition the indication 23 and/or 24 to another part of the view 21, causing the view 25 to display another part of the information space, e.g. relating to programs broadcast in the morning by another set of TV channels. If many programs have been rejected by the user profile, the view 21 enables the user to easily find the programs accepted by the user profile, and quickly move the detailed view 25 to such accepted programs. In a further embodiment, the user is allowed to select the time-span represented by the view 21, e.g. a day or a week. Parameters of the reduced representations, such as shape, size or color, may change accordingly. Alternatively, multiple zoomed-out views may be displayed simultaneously, each representing a different time-span. Also, the user may be enabled to scroll the view 21, in a manner similar to scrolling the view 25. The view 21 may include a further time axis (not shown) in addition to the time axis 26 of the view 25. It may occur that parts of the view 21 do not show any reduced representations of programs, due to the filtering effect of the user-profile, or simply because at the corresponding clock-times no programs are broadcast at all. For example, an area 22 may represent a time period ranging from 3:00 to 6:00, during which no programs (in accordance with the user profile) are broadcast. In order to utilize screen space efficiently, the area 22 may be reduced in size or skipped partially, respectively causing a non-linearity or an interruption in the time-axis of the view 21. Alternatively, the user may be allowed to indicate that certain parts of the day or week are skipped anyway, irrespective of whether desirable programs are broadcast at those times, e.g. the user may want to see only program data of programs broadcast in the evenings and weekends. In summary, the invention relates to a method of and apparatus for displaying an electronic program guide. Program data, e.g. titles, are displayed in a detailed view along one or more coordinate axes, e.g. representing TV channels and broadcast times. Additionally, an area of the screen shows a zoomed-out view comprising reduced representations of the programs. It is indicated which reduced representations correspond to the programs displayed in the detailed view. The user is allowed to scroll through the information in both the detailed and the zoomed-out view. Although the invention has been described with reference to particular illustrative embodiments, variants and modifications are possible within the scope of the inventive concept. Thus, for example, instead of two axes being used to display information units in a matrix, as shown in the above embodiments, the invention could be applied to a system using only one axis, or three axes visualized in a three-dimensional way. A one-axis system may, for example, be a document processing system comprising a scroll-bar which is adapted to show reduced representations of the elements constituting a document, e.g. sentences or paragraphs. The reduced representations may be small lines within the scroll-bar, the length of a line reflecting the length of the corresponding paragraph. The word 'comprising' does not exclude the presence of other elements or steps than those listed in a claim. In the claims, any reference signs placed between parentheses shall not be construed as limiting the claim. The invention can be implemented by means of hardware comprising several distinct elements, and by means of a suitably programmed computer. In the device claim enumerating several means, several of these means can be embodied by one and the same item of hardware.

Claims: CLAIMS: 1. A method of displaying information units, e.g. receivable programs in an electronic program guide (EPG), comprising the steps of: obtaining attribute values relating to attributes of said information units, e.g. channel name, broadcast time, program category, and program title of said receivable programs, defining at least one coordinate axis representing one of said attributes, e.g. broadcast time or channel, relating a coordinate position along said coordinate axis to each of the information units in accordance with their attribute values, - displaying an attribute value, e.g. program title, for at least some of the information units related to a coordinate position on a visible part of the coordinate axis, characterized in that the method further comprises a step of displaying reduced representations, e.g. dots or lines, of attribute values of information units relating to coordinate positions of a further part of the coordinate axis, which further part includes said visible part and is substantially larger than said visible part. 2. A method as defined in claim 1, characterized in that said further part of the coordinate axis includes the whole coordinate axis. 3. A method as defined in claim 1 or 2, characterized in that said attribute values and said reduced representations are displayed simultaneously. 4. A method as defined in any one of claims 1 to 3, characterized in that different parameters, e.g. size or color, of said reduced representations correspond to different attribute values of said information units, e.g. duration, genre of receivable programs. 5. A method as defined in any one of the claims 1 to 4, characterized in that the method further comprises a step of indicating which portion of said further part of the coordinate axis corresponds to said visible part of the coordinate axis. 6. A method as defined in claim 5, comprising a step of selecting a different part of the coordinate axis as said visible part, characterized in that said selection is performed by repositioning said indication along said further part of the coordinate axis. 7. A method as defined in any one of the claims 1 to 6, comprising a step of selecting or rejecting said information units in accordance with a filter, e.g. a user profile in an EPG, characterized in that the method further comprises a step of indicating said rejected information units by a parameter of the reduced representations relating to the rejected information units, e.g. semi-transparency, faint color or total absence. 8. A method as defined in claim 7, characterized in that the method further comprises a step of further reducing groups of reduced representations relating to rejected information units so as to allocate more space to reduced representations relating to selected information units. 9. An data carrier storing a computer program for carrying out the steps of the method as defined in any one of the claims 1 to 8. 10. An information processing device for carrying out the steps of the method as defined in any one of the claims 1 to 8. 11. An apparatus for receiving a plurality of programs, comprising: decoding means for receiving and decoding attribute values relating to attributes of said programs (e.g. channel number, broadcast time, program category, or program title), display means for relating a coordinate position along a coordinate axis to each of the programs in accordance with their attribute values, the coordinate axis representing one of said attributes, e.g. time or channel, and displaying an attribute value, e.g. program title, for at least some of the programs related to a coordinate position on a visible part of said coordinate axis, characterized in that the display means are adapted to display reduced representations, e.g. dots or lines, of attribute values of programs relating to coordinate positions of a further part of the coordinate axis which further part includes said visible part and is substantially larger than said visible part. 12. An apparatus as defined in claim 11, characterized in that said further part of the coordinate axis includes the whole coordinate axis. 13. An apparatus as defined in claim 11 or 12, characterized in that said attribute values and said reduced representations are displayed simultaneously. 14. An apparatus as defined in any one of the claims 11 to 13, characterized in that different parameters, e.g. size or color, of said reduced representations correspond to different attribute values of said programs, e.g. duration, genre. 15. An apparatus as defined in any one of the claims 11 to 14, characterized in that the display means are further adapted to indicate which portion of said further part of the coordinate axis corresponds to said visible part of the coordinate axis. 16. An apparatus as defined in claim 15, comprising selection means for user operably selecting a different part of the coordinate axis as said visible part, characterized in that the selection means are adapted to perform said selection by repositioning said indication along said further part of the coordinate axis. 17. An apparatus as defined in any one of the claims 11 to 16, comprising filtering means for selecting or rejecting said programs in accordance with a filter, e.g. a user profile, characterized in that the display means are further adapted to indicate said rejected programs by a parameter of the reduced representations relating to the rejected programs, e.g. semi- transparency, faint color or total absence. 18. An apparatus as defined in claim 17, characterized in that the display means are adapted to further reduce groups of reduced representations relating to rejected programs so as to allocate more space to reduced representations relating to selected programs.

Inventors: DIEDERIKS ELMO M A, DIEDERIKS, ELMO, M., A.
Applicants: KONINKL PHILIPS ELECTRONICS NV, KONINKLIJKE PHILIPS ELECTRONICS N.V.
Application year: 2000
Main classification: H04N5
IPC codes: H04N5, H04N7