JP2006040097A - Av network equipment, data transfer method therefor, program and recording medium - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To uniquely associate an object handle that is an access interface from a path name expressing each entry inside a file system when opening the file system of AV network equipment itself to connection equipment in the AV network equipment. <P>SOLUTION: About the object handle having a 4-byte data configuration, 1 is set in an entry attribute F1 field when an entry is a directory, 0 is set when the entry is a file, 0 is set in a reservation area F2 field, a directory number of the entry is set in a directory number F3 field, and a file number of the entry is set in a file number F4 field. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a technique for transferring data related to a file system of an AV network device used by connecting to a USB (Universal Serial Bus) to the network. In the following description, the USB technology is described at http: // www. usb. It conforms to the standard described in org / home.

  In recent years, when an image taken using a DV camcorder (hereinafter referred to as DVC) or a digital still camera (hereinafter referred to as DSC) is to be referred to by another device such as a personal computer (hereinafter referred to as PC) or a printer, the image data is captured from the photographing device. In addition to the method of physically taking out the stored recording medium and then inserting it into a reference device for reference (FIG. 9A), the image data is transmitted as an electrical signal using the network while the recording medium is still built in. As a transfer method (FIG. 9B) is becoming common. As a protocol for realizing the latter method, PTP (Picture Transfer Protocol) for the purpose of transferring data, in particular, image data, was standardized in 2000 from PIMA (Photographic And Manufacturing Association, Inc.). (PIMA 15740: 2000). PTP is a protocol that can be operated on a network such as USB, IEEE 1394, IrDA (Infrared Data Association), etc. In particular, in USB, a still image capture device standardizes the adoption of PTP, and DVC, DSC and printers. As an example, the PictBridge function that realizes direct printing between them is already installed in many products. The present invention is a proposal relating to a data transfer system for a system employing PTP in a network form for transferring these image data.

When using the PTP standard, a DVC or DSC (hereinafter, device device) is required to manage data stored in a built-in recording medium using a file system that is uniquely defined. When a PC or printer (hereinafter referred to as a host device) accesses these data, a 4-byte numeric value is used to specify each entry (data group corresponding to a directory or file when the file system is managed in a hierarchical structure). (Hereinafter referred to as object handle) is specified. This object handle is an independent value that the device device uniquely assigns to each entry. As a result, there is an advantage that the host device can access each entry without being aware of the structure of the file system of the device device. This relationship is shown in FIG. Here, the method of associating each entry with the object handle is not particularly defined except that a one-to-one relationship is established and it is required to remain unchanged while connected to the network. You may implement it using your own definition. As an example, in the PTP standard, a method of allocating object handles in order from 0x00000001 in the order of entry management is given (hereinafter, method 1). Japanese Patent Laid-Open No. 2002-369106 describes a method in which a common value is used for the lower two bytes of an object handle in an entry group including a file group named a main file or a sub file and a parent directory thereof (hereinafter referred to as a “main file”). Method 2).
JP 2002-369106 A

  The above-mentioned two methods certainly satisfy the PTP standard and realize transfer of image data using a network. However, the device device adopting the method 1 or the method 2 must always store the relationship between each entry and the corresponding object handle. In both methods, the method of associating entries with object handles depends on the file system configuration at that time, so if an entry is deleted or added and the file system configuration changes, it will be handled before the change. This is to prevent the attached object handle and the object handle associated after the change from being different in value. In the method 2, a storage area for these is provided as the buffer memory 8 shown in FIG. 2 of JP-A-2002-369106. In addition, in Method 1, when the number of entries is very large, for example, in an SD (Secure Digital) card that is one of recording media, the SD-Picture standard (SDA: stipulation by SD Card Association) Although a file system configuration including 9999 × 900 entries is permitted, when a device device incorporates such a recording medium, there is a problem that it takes time to associate entries with object handles. For example, when acquiring an object handle of an entry managed at the final position in a recording medium in which 999 × 9000 entries are managed, a device device having an access mechanism that requires 0.05 milliseconds to search for one entry. For example, the search for the entry managed at the final position takes a little more than 7 minutes. In this case, the advantage that the entry can be easily accessed using the network is halved. In method 2, the file system conforms to the DCF standard (JEIDA-49-2-1998 DCF Version 1.0), which is one of the image format standards to which the PTP standard conforms, and has a file system in which a plurality of DCF directories exist. In some cases, there are a plurality of files corresponding to a file named as a main file in Japanese Patent Laid-Open No. 2002-369106, and in this case, data related to association of object handles must be further stored. As described above, the conventional technique has a problem in that it requires a storage capacity when associating each entry in its own file system with an object handle, and the time required for the association cannot be predicted. .

  The present invention does not require a storage capacity when associating each entry in the file system owned by the object with the object handle, and can keep the time required for the association constant regardless of the configuration of the file system. An object of the present invention is to provide an AV network device.

  In order to solve the above problems, an AV network device according to the present invention is an AV network device used in a system for transferring data of a recording medium managed using a unique file system between AV network devices connected by a network. An object handle allocation unit that allocates a unique object handle to each entry using an entry number included in an absolute path indicating the entry for an entry managed by the file system, and an entry from the object handle allocated by the object handle allocation unit The path derivation means for extracting the number and deriving the absolute path indicating the entry, and the object handle assigned by the object handle assignment means for the data access of the recording medium to the network connection device. Those having access means for an interface, and data transfer means for transferring the data read or written from the recording medium by the access means on the network.

  As described above, in the AV network device of the present invention, when an object handle used for access is associated with an entry managed by the file system, a unique directory number and file number included in the path representing each entry in the structure of the object handle Since the object handle can be uniquely determined by using, it is possible to provide a device and a data transfer method that do not require a capacity for storing the object handle and a file system search process.

  An AV network device according to claim 1 of the present invention is an AV network device used in a system for transferring data of a recording medium managed using a unique file system between AV network devices connected via a network, An object handle assigning means for assigning a unique object handle to each entry using an entry number included in an absolute path indicating the entry for an entry managed by the system, and an entry number is extracted from the object handle assigned by the object handle assigning means. A path derivation unit for deriving an absolute path indicating an entry, and an object handle allocated by the object handle allocation unit for the data access interface of the recording medium to the network connection device And access means to, in which a data transfer means for transferring the data read or written from the recording medium by the access means on the network.

  A data transfer method according to claim 2 of the present invention is a method for transferring data on a recording medium managed by an AV network device connected via a network using a unique file system, which is managed by the file system. An object handle assignment step for assigning a unique object handle to each entry using an entry number included in the absolute path indicating the entry for the entry, and a path derivation step for extracting an entry number from the object handle and deriving an absolute path indicating the entry And an access step in which the object handle is a data access interface of the recording medium to the network connection device, and a data transfer step of transferring data read / written from the recording medium on the network. It is.

  According to a third aspect of the present invention, there is provided a recording medium for recording a computer program for executing the data transfer method, and a fourth aspect relates to the computer program itself.

(Embodiment 1)
FIG. 2 is a diagram for explaining the configuration of the AV network device according to the first embodiment of the present invention. Hereinafter, the configuration of the AV network device will be described with reference to FIG.

  Reference numeral 1 denotes the AV network device itself of the present invention. Reference numeral 2 denotes another connection device. Reference numeral 3 denotes a data transmission line, through which the AV network device 1 and the connected device 2 transmit and receive data. An input / output data conversion unit 15 converts data output to the data transmission line 3 into a predetermined format, and interprets data of a predetermined format input from the data transmission line 3 to extract necessary data. Reference numeral 16 denotes an object handle conversion unit which associates a path indicating an entry of a file system managed by the media control unit 13 described later with an object handle. A main control unit 12 controls processing operations of the AV network device 1 and includes a ROM for storing computer programs and a RAM as a work area. Reference numeral 13 denotes a media control unit which manages data stored in a recording medium 14 (to be described later) using a unique file system and serves as an interface function between the recording medium 14 and the main control unit 12. Here, the file system managed by the media control unit 13 has a directory structure starting from the root directory. For specifying individual data, an absolute path in which entries (directories and files) names are arranged from the closest to the root directory. (The following path) is used. Next, reference numeral 14 denotes a recording medium, which stores arbitrary data via the media control unit 13. A user operation input unit 11 inputs a control command for the AV network device 1 by the user and transmits the control command to the main control unit 12.

  Next, the operation of the AV network device according to the first embodiment will be described with reference to the flowcharts of FIGS. The flowchart shown in FIG. 4 shows a series of operations until data is transmitted to the connected device 2 with the occurrence of control by the user as to the AV network device 1 as an operation start trigger. Hereinafter, this operation is referred to as an event transmission operation, and data transmitted to the connected device 2 in the event transmission operation is referred to as event data. The flowchart shown in FIG. 5 shows a series of operations until data is transmitted to the connected device 2 using reception of data transmitted by the connected device 2 as a trigger for starting operation. Hereinafter, this operation is called a request reception operation, data transmitted from the connection device 2 in the request reception operation is called request data, and data transmitted to the connection device is called response data.

  First, the event transmission operation will be described. The AV network device 1 and the connection device 2 are in a state where data can be transmitted and received through the data transmission line 3. The trigger for starting the operation is the occurrence of control by the user on the AV network device 1 detected by the user operation input unit 11. The user operation input unit 11 transfers the control content by the user to the main control unit 12. The main control unit 12 performs a predetermined process according to the control content (step A1). If these processes require access to the data in the recording medium 14, the main control unit 12 accesses the recording medium 14 via the media control unit 13 (steps A2 and A3). Subsequently, the main control unit 12 creates processing results and event data to be transmitted to the connected device 2, and transfers them to the input / output data conversion unit 15 (step A4). If the event data includes data representing a path in the event data, the input / output data conversion unit 15 transfers the data to the object handle conversion unit 16 (step A5). The object handle conversion unit 16 derives an object handle corresponding to the path using an object handle derivation method described later, and transfers the derived data to the input / output data conversion unit 15 (step A6). The input / output data converter 15 converts the event data in which the object handle data is inserted instead of the path data into a data structure according to a predetermined format, and transmits the data structure to the data transmission line 3 (step A7). Thereafter, the connected device 2 receives event data from the data transmission line 3 (step A8), and the event transmission operation ends.

  Next, a request receiving operation will be described. The AV network device 1 and the connection device 2 are in a state where data can be transmitted and received through the data transmission line 3. An operation start trigger is a request data transmission to the AV network device 1 by the connected device 2. The input / output data converter 15 receives the request data transmitted from the data transmission line 3 (step B1), and if the request data includes data representing an object handle, the input / output data converter 15 converts the data into the object handle converter 16 (Step B2). The object handle conversion unit 16 derives a path corresponding to the object handle by using a path derivation method described later, and transfers the value to the input / output data conversion unit 15 (step B3). The input / output data conversion unit 15 transfers the request data in which the path data is inserted instead of the object handle data to the main control unit 12. The main control unit 12 performs a predetermined process according to the content of the request data (step B4). When these processes require access to the data in the recording medium 14, the main control unit 12 accesses the recording medium 14 via the media control unit 13 (steps B5 and B6). Subsequently, the main control unit 12 creates a processing result and response data to be transmitted to the connected device 2, and transfers them to the input / output data conversion unit 15 (step B7). When the response data includes data representing a path, the input / output data converter 15 transfers the data to the object handle converter 16 (step B8). The object handle conversion unit 16 derives an object handle corresponding to the path using an object handle derivation method described later, and transfers the derived data to the input / output data conversion unit 15 (step B9). The input / output data converter 15 converts the response data in which the object handle data is inserted instead of the path data into a data structure according to a predetermined format, and transmits the data structure to the data transmission line 3 (step B10). Thereafter, the connected device 2 receives the response data from the data transmission line 3 (step B11), and the request receiving operation ends.

  Next, the configuration of a 4-byte object handle determined by the object handle conversion unit 16 will be described. First, the object handle has a 4-byte configuration (hereinafter referred to as field configuration) shown in FIG. In FIG. 1, F1 is a 1-bit data area called an entry attribute, and indicates whether the entry indicated by the object handle is a directory or a file. 1 corresponds to the case where the entry is a directory, and 0 corresponds to the case where the entry is a file (FIG. 3). Next, F2 is a data area of n1 bits (n1 is an integer of 0 or more) called a reserved area, and 0 always corresponds. F3 is a data area of n2 bits (n2 is an integer of 0 or more) called a directory number, and corresponds to the directory number of the directory at the lowest layer of the path indicating the entry (the root directory is the highest layer). The directory number refers to a number used for a directory name, and the position, number of characters, and value used are uniquely determined by the file system. For example, in FIG. 8A, in the path 1, the directory name of the lowermost directory is 100CDPFP, and when the file system determines the position and the number of characters of the directory number from the beginning of the directory name to the third character, the directory number is 100. Further, when the directory name of the lowermost directory does not include a directory number, or when the lowermost directory is a root directory, 0 corresponds to the directory number F3. Next, F4 is a data area of n3 bits (n3 is an integer of 0 or more, and 1 + n1 + n2 + n3 = 32) called a file number. If the entry is a file, the file number corresponds. A file number refers to a number used for a file name, and the position, number of characters, and value used are uniquely determined by the file system. For example, in path 1 of FIG. 8A, the file name is IMGA0001. If the file system is JPG and the file system sets the position and the number of characters of the file number to the fifth character from the beginning of the file name to the eighth character, the file number is 1. When the file name does not include a file number and when the entry is a directory, 0 corresponds to the file number F4.

  Next, with respect to a method for deriving an object handle indicating the same entry as the entry indicated by the path from the given path (object handle deriving method), the object handle field configuration diagram of FIG. 1 and the flowchart of FIG. 6 will be used. explain. First, 0 is set in the reserved area F2 (step C1). Then, the directory name of the lowest directory in the path is checked (step C2). If the directory name includes a directory number, the directory number is set in the directory number F3 (step C3a), and the directory name includes the directory number. If not, or if the lowest directory is the root directory, 0 is set to the directory number F3 (step C3b). Subsequently, the entry indicated by the path is checked (step C4). If the entry is a directory, 1 and 0 are set in the entry attribute F1 and the file number F4, respectively (step C5a and step C7a), and the entry is a file. The entry attribute F1 is set to 0 (step C5b), the file name is further checked (step C6), and if the file name includes the file number, the file number is set to the file number F4 (step C7b). If the file number does not include the file number, 0 is set to the file number F4 (step C7c). As described above, the value set from F1 to F4 is an object handle indicating the same entry as the entry indicated by the designated path, and the derivation is terminated (step C8).

  Next, a method for deriving a path indicating the same entry as the entry indicated by the object handle from the given object handle (path deriving method) will be described with reference to the field configuration diagram of the object handle in FIG. 1 and the flowchart in FIG. explain. First, the reserved area F2 is examined (step D1). If the reserved area F2 is other than 0, there is no entry indicated by the given object handle, and the derivation is terminated (step D7b). If the reserved area F2 is 0, the directory number F3 is checked next (step D2). When the directory number F3 is 0, the directory name of the lowest directory in the path is determined as a directory name that does not include the directory number, or the lowest directory in the path is determined as the root directory. (Step D3a). Which is determined is uniquely determined in the file system. When determining the directory name of the directory at the lowest layer of the path as a directory name that does not include a directory number, the directory name is uniquely determined in the file system. In step D2, if the directory number F3 is a value within the range determined as the directory number in the file system, the directory name of the lowermost directory is determined to be a directory name having the directory number F3 as the directory number ( Step D3b). Here, characters other than the directory number used for the directory name and the directory name of the directory that is not the lowest layer are uniquely determined in the file system. In step D2, if the directory number F3 is neither 0 nor a value within the range determined as the directory number in the file system, the entry indicated by the given object handle does not exist, and the derivation is terminated (step D7b). Next, the entry attribute F1 is examined (step D4). When the entry attribute F1 is 1, the entry indicated by the object handle indicates a directory, and the file number F4 is further examined (step D5a). When the file number F4 is 0, the entry indicated by the given object handle exists as a directory. If the file number F4 is other than 0, there is no entry indicated by the given object handle, and the derivation is terminated (step D7b). If the entry attribute F1 is 0 in step D4, the entry indicated by the object handle indicates a file, and the file number F4 is checked (step D5b). If the file number F4 is 0, the file name is determined as a file name that does not include the file number (step D6a). The file name at this time is uniquely determined in the file system. When the file number F4 is a value within the range determined as the file number in the file system, the file name is determined as a file name having the value of the file number F4 as the file number (step D6b). Here, characters other than the file number used for the file name are uniquely determined in the file system. Finally, if the file number F4 is neither 0 nor a value within the range determined as the file number in the file system, the entry indicated by the object handle does not exist, and the derivation is terminated (step D7b). The path determined as described above is a path indicating the same entry as the entry indicated by the designated object handle, and the derivation is terminated (step D7a).

  FIG. 8 shows, as an example of the correspondence between the path and the object handle using the above method, a list of the entries indicated by the configuration path according to the naming rule of the DCF standard and the object handles corresponding to them. The object handle shown in FIG. 8B is an example when the field configuration is n1 = 3, n2 = 12, and n3 = 16.

  As described above, according to the AV network device and the data transfer method of the present invention, when the path indicating the same entry managed by the file system is associated with the object handle, the path directory number and the data constituting the object handle Since the file number is used, it can be uniquely derived regardless of the configuration of the file system, and does not require a storage capacity for storing the object handle. Further, since the file system search is not required at the time of association, it is possible to keep the time required for the association constant within a predictable time regardless of the configuration of the file system.

  In the first embodiment, the reserved field F2 is set to 0 in the field structure of the object handle in the object handle allocating unit. However, a configuration having an arbitrary definition may be used. More configuration paths, that is, entry management can be realized in the system. Further, the directory number F3 is associated with the directory number of the directory name of the lowest layer, but may be configured to associate the directory number of the directory name of the other layer with each other, or may be configured to associate the directory numbers of a plurality of directory names. Also in this case, more configuration paths, that is, entry management can be realized. In the present embodiment, each unit is controlled by a computer program, and the computer program can be recorded on another recording medium and executed.

  The present invention is effective for use in a system in which a digital video camera or digital still camera is connected to a personal computer or a printer, but can be applied to a combination of other devices as long as the device is compatible with the connection. It is.

The figure which shows the field structure of the object handle in Embodiment 1 of this invention. 1 is a block diagram showing a configuration of an AV network receiver in Embodiment 1 of the present invention. The figure which shows the setting value and meaning of an entry attribute field in the field structure of the object handle in Embodiment 1 of this invention The figure which shows the flow of the operation | movement which performs event transmission of the AV network receiver in Embodiment 1 of this invention. The figure which shows the flow of the operation | movement which performs request reception and response transmission of the AV network receiver in Embodiment 1 of this invention. The figure which shows the flow of the method of allocating the object handle from a path in the object handle allocation means with which the AV network receiver in Embodiment 1 of this invention is provided. The figure which shows the flow of the method of allocating a path | pass from an object handle in the object handle allocation means with which the AV network receiver in Embodiment 1 of this invention is provided. (A) A diagram showing entries represented by a path configuration in accordance with the DCF standard. (B) A diagram showing object handles assigned to the entries in FIG. 9 (A). (A) The figure which shows the data transfer form by attachment / detachment of a recording medium, and insertion (B) The figure which shows the data transfer form by network transmission The figure which shows the access form to the recording media by using the object handle

Explanation of symbols

F1 entry attribute field F2 reserved area field F3 directory number field F4 file number field 1 AV network device 2 connected device 3 data transfer line 11 user operation input unit 12 main control unit 13 media control unit 14 recording medium 15 input / output data Conversion unit 16 Object handle conversion unit

Claims (4)

An AV network device used in a system for transferring data of a recording medium managed using a unique file system between AV network devices connected by a network, and an absolute path indicating an entry for the entry managed by the file system Object handle assigning means for assigning a unique object handle to each entry using the entry number included in the object, and path derivation means for extracting an entry number from the object handle assigned by the object handle assigning means and deriving an absolute path indicating the entry Access means that uses the object handle assigned by the object handle assigning means as a data access interface of the recording medium to a network connection device; AV network device, characterized in that it comprises a data transfer means for transferring data read or written from the recording medium on the network by Seth means. A method of transferring data of a recording medium managed by an AV network device connected by a network using a unique file system, wherein an entry number included in an absolute path indicating an entry is assigned to an entry managed by the file system. An object handle assignment step for assigning a unique object handle to each entry, a path derivation step for extracting an entry number from the object handle and deriving an absolute path indicating the entry, and the recording medium for the network connection device. An AV network comprising: an access step as a data access interface; and a data transfer step of transferring data read / written from the recording medium onto the network. Vessel method of data transfer. An object handle assignment step for assigning a unique object handle to each entry using an entry number included in an absolute path indicating the entry for an entry managed by the file system, and an entry by extracting the entry number from the object handle A path derivation step for deriving an absolute path, an access step using the object handle as a data access interface of the recording medium to a network connection device, and a data transfer step for transferring data read / written from the recording medium onto the network The computer-readable recording medium which recorded the program for performing this. From the object handle allocated by the object handle allocation unit, an object handle allocation unit that allocates a unique object handle to each entry using an entry number included in an absolute path indicating the entry for an entry managed by the file system A path deriving unit for extracting an entry number and deriving an absolute path indicating the entry; an access unit that uses the object handle allocated by the object handle allocation unit as a data access interface of the recording medium to a network connection device; and the recording by the access unit A program for functioning as a data transfer means for transferring data read / written from / on media to a network.

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