JP3719591B2 - Receiver - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a DSM-CC carousel receiving apparatus and a receiving apparatus that receives data of a system.
[0002]
[Prior art]
In recent years, data broadcasting has been provided by digital broadcasting or the like, and a DSM-CC (Digital Storage Media-Command and Control) carousel method is used as one method.
[0003]
The DSM-CC carousel is composed of two types of sections, DII (Download Info Indication) and DDB (Download Data Block), as defined by ISO / IEC13816-6, and is a method of repeatedly sending them. is there.
[0004]
The DII section contains information about the module being sent, and the DDB section contains data that actually configures the module.
[0005]
In the DSM-CC carousel method, data to be transmitted is stored in a unit called a module, which is divided and transmitted as DSM-CC section data. There are two methods for storing data in the module. . One is called 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 storing a plurality of data in one module and is shown in FIG.
[0006]
When there is a lot of data to be transmitted as program data, it is received in units of modules once from the transmission path, and can be expanded inside the receiving device to obtain necessary resource data. This entity mapping format is adopted in many data broadcasting programs with high efficiency.
[0007]
On the other hand, the data once read into the receiving apparatus is stored in a memory called a cache memory in order to use it efficiently when requested again. Since data is stored in this cache memory in units of data requested for acquisition first, for example, if there is an acquisition request for a direct mapping format module, the module data is stored in the cache memory as it is. When resource data is acquired from a module in the entity mapping format, only resource data is stored in the cache memory, and the module data itself is discarded.
[0008]
[Problems to be solved by the invention]
However, when only one resource data is acquired for a module that stores a large number of resource data, much of the received module data is wasted. Moreover, even if the resource data is in the same module, if the resource data has not been requested so far, the module will be reacquired and the time required for data acquisition will become longer, and the entity mapping format There was a problem that it would be impossible to take advantage of the module.
[0009]
Therefore, according to the receiving apparatus according to the present invention, when acquisition of certain resource data is requested and module data in the entity mapping format is acquired, not only the requested resource data but also all stored in the module data By acquiring the resource data and storing it in the cache memory, when there is an acquisition request for the resource data in the module described above for the second time or later, the cache is acquired without acquiring the resource data from the transmission system. The object is to acquire data on a memory and acquire data at extremely high speed.
[0010]
[Means for Solving the Problems]
In order to solve the above-described problem, an entity mapping format module is a receiving device that receives data transmitted by the DSM-CC data carousel method, and requests acquisition of one resource data from the entity mapping format module. An acquisition request unit to perform, a resource list analysis unit for identifying the resource data in response to an acquisition request from the acquisition request unit, and analyzing a resource list of a module including the resource data, and an acquisition from the acquisition request unit In response to the request, data reading means for acquiring not only the resource data but also all resource data included in the module containing the resource data;
Storage means for storing all the resource data read by the data reading means, and in response to an acquisition request for other resource data in the acquisition request means, the other resource data is stored in the storage means A receiving apparatus is characterized in that the resource list analyzing means checks whether or not it has been stored and, if stored, reads out resource data from the storage means.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
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 its operation.
[0012]
According to FIG. 2, when acquisition of certain resource data is requested and module data 4 in the entity mapping format is acquired, not only the requested resource data but also all resource data stored in the module data 4 are obtained. The income is stored in the cache memory 3.
[0013]
A resource list indicating what kind of resource data the module data 4 has is stored at the head of the module data 4 in the entity mapping format. The resource list includes a resource name, a read offset from the head, Data length etc. are recorded. The resource list is read by the resource list analysis unit 1 and the resource data described in the resource list is sequentially acquired and stored in the cache memory 3.
[0014]
Actually, the resource data requested to be acquired is read from the module data 4 by the data reading unit 2 (process (1)) and stored in the cache memory 3. Thereafter, other resource data without an acquisition request is read from the module data 4 by the data reading unit 2 (processing (2) to (5)), and the resource described in the module data 4 by the resource list analysis unit 1 The list is stored in the cache memory 3 while being analyzed.
[0015]
The flow will be described below with reference to the flowchart shown in FIG. First, the receiving device receives a resource data income request (S1). Next, the module data 4 in which the resource data requested by the acquisition request is stored is obtained (S2). Then, a resource list is obtained from the acquired module data (S3). The resource data requested from the resource list acquired in this way is extracted from the module data 4 and stored in the cache memory 3 (S4).
[0016]
Then, it is checked whether or not there is other resource data in the acquired resource list (S5). If there is no other resource data (No in S5), the process is terminated, and there is other resource data ( In S5, the process of S6 is continued. In S6, other resource data is extracted from the module data 4 and stored in the cache memory 3. In this way, the processing is continued until all the resource data in the module data 4 is stored in the cache memory 3.
[0017]
As described above, according to the receiving apparatus of the present invention, since all the resource data in the module data 4 read once is stored in the cache memory 3, there is next an acquisition request for the resource data in this module. In this case, since the resource data in the cache memory 3 is acquired without acquiring the resource data from the transmission system, the data can be acquired at a very high speed. In general, the resource data stored in one module data 4 is a unit of a broadcast program, and the resource data is often requested for acquisition at close timing, and the receiving apparatus according to the present invention By storing module data in the cache memory 3 in advance, high-speed and efficient access can be realized in many cases.
[0018]
【The invention's effect】
As described above in detail, according to the receiving apparatus according to the present invention, in response to an acquisition request for certain resource data, the resource data in the module data transmitted by the DSM-CC data carousel method including the resource data is By acquiring all and storing them in the cache memory, when there is a request to acquire resource data in this module data, it can be acquired from the cache memory without acquiring from the transmission system, and resource data is acquired at high speed There is an effect that it becomes possible to do.
[Brief description of the drawings]
FIG. 1 is a diagram illustrating a configuration of module data in a direct mapping format and module data in an entity mapping format.
FIG. 2 is a block diagram showing a configuration of a main part of a receiving apparatus according to the present invention.
FIG. 3 is a flowchart showing the operation of the embodiment of the receiving apparatus according to the present invention.
[Explanation of symbols]
1 Resource list analysis unit 2 Data reading unit 3 Cache memory 4 Module data

Claims (1)

An entity mapping format module is a receiving device for receiving data transmitted by the DSM-CC data carousel method,
An acquisition request means for requesting acquisition of one resource data from the entity mapping format module;
Resource list analysis means for identifying the resource data in response to an acquisition request from the acquisition request means, and analyzing a resource list of a module including the resource data;
In response to an acquisition request from the acquisition request unit, a data reading unit that acquires not only the resource data but also all resource data included in the module containing the resource data;
Storage means for storing all the resource data read by the data reading 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. A receiving apparatus, wherein resource data is read from the means.

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