Technique for providing program guide data through a communications network delivering programming content
In order to efficiently utilize the limited transmission bandwidth of a communications network, e.g., a cable network, guide data for constructing an interactive program guide (IPG) is delivered to a set-top terminal using different methodologies. For example, the guide data associated with those programs which are likely of interest to a user is automatically provided piecemeal in a broadcast stream. The set-top terminal, along with other terminals, may retrieve from such a broadcast stream some or all of the guide data therein over time, which is cached in the terminal in anticipation of a user's invocation of an IPG. On the other hand, the guide data associated with those programs which are less likely of interest to a user is furnished upon request by the set-top terminal needing such guide data to realize an IPG desired by the user. In addition, guide data for each program may be divided into detail guide data providing details of the program (e.g., a synopsis of the program content), and grid guide data providing basic information about the program (e.g., title, channel and broadcast time). A first time window and a second time window may be defined such that the grid guide data associated with those programs broadcast within the first time window and the detail guide data associated with those programs broadcast within the second time window are automatically provided in the broadcast stream. The rest of the detail and grid guide data may be furnished upon request when needed.
1. Apparatus for providing information concerning at least one program delivered through a communications network, the apparatus comprising:
an interface for receiving over the communications network a data object containing the information, the data object including a string reference providing information on the location of a string descriptive of the program, the string reference including a value in a predetermined location indicating whether the string is located within the data object or is located within a global string table external to the data object, said global string table including strings which can be referenced by a plurality of different data objects;
a processor for determining based on the value at the predetermined location whether the string reference indicates that the string is located within the data object or in the global string table; and
wherein, when said value in the string reference indicates that the string is located within the data object, the string reference also includes a set of bits indicating a position of the string descriptive of said program in a block of local strings located within the data object.
2. The apparatus according to claim 1 , wherein the string reference is repeated within the data object multiple times.
3. The apparatus according to claim 1 , wherein the value in the predetermined location includes a single bit used to indicate if the string is located within the data object or that the string is located within the global string table external to the data object.
4. The apparatus according to claim 1 ,
wherein the string is a text string providing a title of the program; and
wherein said data object includes multiple text strings, said string being one of said multiple text strings when said value indicates that the string is located within the data object.
5. The apparatus according to claim 1 , further comprising:
a set-top terminal; and
wherein the information includes program guide data.
6. The apparatus according to claim 1 , wherein data in the data object is compressed.
7. A method for providing information concerning at least one program delivered through a communications network, the method comprising:
receiving over the communications network a data object containing the information, the data object including a string reference providing information on the location of a string descriptive of the program, the string reference including a value in a predetermined location indicating whether the string is located within the data object or within a global string table external to the data object, said global string table including strings which can be referenced by a plurality of different data objects;
using a processor to determine based on the value at the predetermined location whether the string reference indicates that the string is located within the data object or in the global string table; and
wherein, when said value in the string reference, indicates that the string is located within the data object, the string reference also includes a set of bits indicating a position of the string descriptive of said program in a block of local strings located within the data object.
8. The method according to claim 7 , wherein the string reference is repeated within the data object.
9. The method according to claim 7 , wherein the value in the predetermined location that includes a single bit used to indicate if the string is located within the data object or that the string is located within the global string table external to the data object.
10. The method according to claim 7 , wherein the string is a text string providing a title of the program.
11. The method according to claim 7 , wherein at least part of the string reference defines a location of the string.
12. The method according to claim 7 , wherein the information includes program guide data.
13. The method according to claim 7 , wherein data in the data object is compressed.
14. The method of claim 7 , wherein said string reference includes string offset bits indicating where within the block of local strings the string descriptive of said program begins.
15. The method of claim 7 , wherein said string reference indicates the location of said string descriptive of said program in the global string table when said string reference indicates the string is located in the global string table external to said data object.
16. The method of claim 15 wherein said different data objects are different catalogs of program information.
17. The method of claim 15 , wherein said data object is a catalog including program guide data.
18. The method of claim 17 , wherein said string is a text string indicating the title of a program.