JP2003032135A - Receiver - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a receiver that can acquire resource data from a cache memory rather than acquiring the data from a transmission system when received an acquisition request of the resource data in module data, thereby resulting in acquiring the resource data at a high-speed. SOLUTION: The receiver includes an acquisition request means for making an acquisition request of resource data from a module adopting an entity mapping format, a resource list analysis means for identifying resource data in response to the acquisition request from the acquisition request means and analyzes a resource list of modules including the resource data, a data read means for acquiring all the resource data included in the modules not only the resource data that responds to the acquisition request from the acquisition request means, and a storage means for storing all the resource data read by the data read means.

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a DSM-CC carousel receiving apparatus and a receiving apparatus for receiving data of a system. 2. Description of the Related Art In recent years, data broadcasting has been provided by digital broadcasting and the like, and one of the methods is DSM-C.
C (Digital Storage Media-Co
(mand and Control) carousel system. [0003] The DSM-CC carousel is an ISO / IE
As defined in C13816-6, DII (D
download Info Indication) and DDB (Download Data Block)
This is a method of repeatedly sending these sections. [0004] The DII section contains information about the module being sent, and the DDB section contains data that actually constitutes the module. In the DSM-CC carousel system, data to be transmitted is stored in units called modules, and the data is divided and transmitted as DSM-CC section data. There are two methods of storing data in a module. There is a way. One is a direct mapping format, in which one data is directly assigned to one module. The other is called an entity mapping format, which is a method of collectively storing a plurality of data in one module, as shown in FIG. If there is a large amount of data to be transmitted as program data, the data is received once in units of a module from the transmission path, and can be expanded in the receiving device to obtain necessary resource data. Is more efficient, and for many data broadcast programs,
This entity mapping format is adopted. On the other hand, the data once read into the receiving device is stored in a memory called a cache memory in order to use the data efficiently when a request is made again. Since data is stored in this cache memory in the data unit for which the acquisition request was first made, if there is an acquisition request for a module in the direct mapping format, the module data is stored in the cache memory as it is. When resource data is obtained from a module in the entity mapping format, only the resource data is stored in the cache memory, and the module data itself is discarded. However, when only one resource data is obtained from a module storing a large number of resource data, most of the received module data is useless. Will be. In addition, even if the resource data is in the same module, if the resource data has not been requested, the module must be acquired again, which increases the time required to acquire the data. However, there is a problem that the advantage cannot be utilized in the module. Therefore, according to the receiving apparatus of the present invention,
When a certain resource data is requested to be obtained and the module data in the entity mapping format is obtained, not only the requested resource data but also all the resource data stored in the module data are obtained and stored in the cache memory. Therefore, when there is an acquisition request for the resource data in the above-described module from the second time on, the data on the cache memory is acquired without acquiring the resource data from the transmission system, and extremely high-speed data is acquired. The purpose is to perform acquisition. [0010] In order to solve the above-mentioned problems, an entity mapping type module is called D
A receiving device for receiving data transmitted by the SM-CC data carousel method, comprising: an acquisition requesting unit that issues an acquisition request for one resource data from the entity mapping format module; and an acquisition request from the acquisition requesting unit. A resource list analyzing means for analyzing a resource list of a module including the resource data, and in response to an acquisition request from the acquisition request means, not only the resource data but also the resource data. Data reading means for acquiring all the resource data included in the contained module, and storage means for storing the all resource data read by the data reading means, and other resource data in the acquisition request means Other than the above Whether resource data has been stored in the storage means examined by the resource list analyzing means, if it is stored to provide a receiving apparatus characterized by reading the resource data from the storage means. Hereinafter, a receiving apparatus according to the present invention will be described with reference to the drawings. FIG. 2 is a block diagram showing the configuration of the receiving apparatus of the present invention, and FIG. 3 is a flowchart showing the operation thereof. According to FIG. 2, when the acquisition of certain resource data is requested and the module data 4 in the entity mapping format is acquired, not only the requested resource data but also all the data stored in the module data 4 are obtained. The resource data is obtained and stored in the cache memory 3. At the beginning of the module data 4 in the entity mapping format, a resource list indicating what kind of resource data the module data 4 has is stored. The resource list includes a resource name, A read offset, a data length, and the like are recorded. The resource list is read by the resource list analysis unit 1, and resource data described in the resource list is sequentially acquired and stored in the cache memory 3. Actually, the resource data requested to be obtained is read from the module data 4 by the data reading unit 2 (processing (1)) and stored in the cache memory 3. After that, other resource data for which there is no acquisition request is read from the module data 4 by the data reading unit 2 (processing of (2) to (5)), and the resource list analysis unit 1 writes the resource data described in the module data 4. Cache memory 3 while analyzing the list
Stored in The flow will be described below with reference to the flowchart shown in FIG. First, the receiving device receives an income request for resource data (S1). Next, the module data 4 storing the resource data requested by the acquisition request described above is obtained (S2). Then, a resource list is obtained from the obtained module data (S3). The resource data requested from the resource list obtained in this way is stored in the module data 4
And stores it in the cache memory 3 (S4). Then, it is checked whether or not there is other resource data in the obtained resource list (S5). If there is no other resource data (No in S5), the process is terminated, and the other resource data is deleted. If there is (Yes in S5)
, The processing of S6 is subsequently performed. In S6, other resource data is extracted from the module data 4 and stored in the cache memory 3. Thus, module data 4
The processing is continued until all the resource data in the cache memory 3 is stored in the cache memory 3. As described above, according to the receiving apparatus of the present invention, once the resource data in the module data 4 once read is stored in the cache memory 3, the resource data in the module is obtained next. When a request is made, resource data in the cache memory 3 is obtained without obtaining resource data from the transmission system, so that data can be obtained at a very high speed. In general, the resource data stored in one module data 4 is a unit as a broadcast program, and the resource data is often requested to be obtained at a close timing. By storing the module data in the cache memory 3 in advance, high-speed and efficient access can be realized in many cases. As described in detail above, according to the receiving apparatus of the present invention, in response to a request for obtaining certain resource data, the request is transmitted by the DSM-CC data carousel system including the resource data. By obtaining all the resource data in the module data and storing it in the cache memory, when there is a request to obtain the resource data in the module data, it can be obtained from the cache memory without obtaining it from the transmission system. This makes it possible to obtain resource data at high speed.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a diagram showing a configuration of module data in a direct mapping format and module data in an entity mapping format. FIG. 2 is a block diagram illustrating a configuration of a main part of a receiving device according to the present invention. FIG. 3 is a flowchart showing an operation of the embodiment of the receiving apparatus according to the present invention. [Description of Signs] 1 Resource list analysis unit 2 Data reading unit 3 Cache memory 4 Module data

Claims (1)

Claims 1. An entity mapping type module is a receiving apparatus for receiving data transmitted by a DSM-CC data carousel system, and acquiring one resource data from the entity mapping type module. An acquisition requesting unit that makes a request; a resource list analyzing unit that identifies the resource data in response to an acquisition request from the acquisition requesting unit and analyzes a resource list of a module including the resource data; Data reading means for obtaining not only the resource data but also all resource data included in the module containing the resource data in response to the acquisition request, and storing all the resource data read by the data reading means. Storage means In response to an acquisition request for other resource data in the acquisition request unit, the resource list analysis unit checks whether or not the other resource data is stored in the storage unit. Is a receiving device for reading resource data from the storage means.