WO2010049346A1

WO2010049346A1 - Method and device for detecting media data in a removable memory

Info

Publication number: WO2010049346A1
Application number: PCT/EP2009/063906
Authority: WO
Inventors: Thomas Schneider; Michael Wollborn; Andreas Pinkert
Original assignee: Robert Bosch Gmbh
Priority date: 2008-10-28
Filing date: 2009-10-22
Publication date: 2010-05-06
Also published as: DE102008043216A1

Abstract

The invention relates to a method for detecting media data in a removable data carrier or memory (2), wherein the media data are stored as files in the memory (2) preferably with meta information, wherein the files stored in the memory (2) are listed in a file arrangement table (3), wherein an identifier is generated that represents a state of the stored data, wherein the identifier (24) characterizes the file arrangement table (3). The invention further relates to a corresponding device.

Description

description

title

Method and device for detecting media data on a removable memory

State of the art

The invention relates to a method for detecting media data on a removable data carrier or memory according to the preamble of claim 1. Furthermore, the invention relates to a device according to the preamble of claim 8.

Currently, in particular in home entertainment applications, in addition to data on CD or DVD, compressed data formats, such as compressed audio files, are also used. For example, so-called MP3 or WMA

File formats very popular. The MP3 files are played, for example, on so-called stationary or portable MP3 players. The aforementioned files based on the mentioned compressed file formats contain, in addition to the audio data, other data known as meta-information, such as the title of the song, the artist name, the name of the album, the

Genre o.a.

Today's multimedia devices, such as portable media players, play the compressed audio files and process that meta-information to display on a display, such as to depict an artist or song title of a music piece being played.

To further benefit from this meta-information, the devices search the meta-information of all available audio files and store it in a separate local database in a memory of the device. By accessing the entries of the local database can by the Users of the device, for example, a selection of files or audio data to be performed to play, such as a selection of music pieces of a selected artist.

The metadata search typically requires a certain amount of time per pass, which scales with the number of files to be scanned on the storage medium and thus, with a high volume of data, means a non-negligible waiting time for the user. With devices used today, memories such as USB memory or memory cards, with memory sizes of several gigabytes already common, so that on these storage media

Hundreds of thousands or even tens of thousands of files can be stored. This high number of files that can be stored on a storage medium leads to a considerable effort for the search and results in a considerable waiting time that is unacceptable for the user.

In a case where such a removable memory such as USB memory would be connected to a mobile infotainment system of, for example, a vehicle, the system would search the metadata of each file and enter it in a file. This would be done in parallel with the driving of the vehicle and, as described above, would take a considerable amount of time, depending on the number of files. This procedure would be performed each time the infotainment system or a corresponding device is turned on and every time the memory is changed, regardless of whether the media data on the memory has changed or not. Since this is thus also carried out with unchanged data in the memory, such a method will be perceived as disturbing by the user, because a process is repeatedly carried out which would take considerable time and would nevertheless be considered unnecessary.

Disclosure of the invention

It is the object of the invention to provide a method and a device for detecting media data on a removable memory, which or which performs an identification of the stored on the removable memory media data or detects their changes or notes that there are no changes. This is achieved with regard to the method with the features of claim 1, according to which a method is provided for detecting in particular media data on a removable data medium or memory in which the media data are preferably stored with meta-information in the memory as files, wherein the files stored in the memory are listed in a file arrangement table (FAT), wherein an identifier representing a state of the stored data is generated, wherein the identifier characterizes the file arrangement table. This facilitates a later comparison and reduces the effort for searching the memory.

In this case, it is advantageous if the exchangeable memory is searched for the first time a device for playing media data and / or after a first connection of a memory with such a device and meta-information of the files of the memory in a file and / or in a local

Database of the device are stored in the memory. This permits an i-nitial generation of a file or database with the metadata of the files of the removable memory. Furthermore, when the device is first switched on, an identifier of the data stored on the replaceable memory can be generated and stored in the device.

Furthermore, it is expedient if this identifier is generated in such a way that it is either identical to the file arrangement table itself, or it is calculated by means of a so-called HASH function from the file arrangement table; the result of such a HASH function also allows unambiguous identification of the file arrangement table, but is much smaller and therefore requires significantly less storage space in the memory of the device.

Furthermore, it is expedient if, during a further switching on of a device for playing media data or after connecting a memory with such a device, an identifier is again generated which represents a state of the data stored on the exchangeable memory, the identifier comprising the file. Arrangement table characterized. This is then compared with the identifier stored in a memory of the device. This allows a quick comparison of whether the data on the removable memory has changed or not. According to the invention, it is expedient if, when the identifier stored on the device matches the recomputed identifier of the data stored on the exchangeable memory, the metadata of the files of the replaceable memory stored on the device is used for further applications. If no change is detected, a re-search does not have to take place.

On the other hand, if the identifier stored on the device does not coincide with the recalculated identifier of the data stored on the removable memory, the metadata of the files of the removable memory are searched again. In such a case, the thus recomputed identifier of the data stored on the removable memory is stored in the device. Thus, the removable memory is always searched only if it has a change. This saves time and significantly improves user acceptance.

The object with regard to the device is achieved with a device in particular for carrying out a method for detecting media data on a removable data medium or memory, wherein the media data preferably with

Meta information in the memory are stored as files, wherein the files stored in the memory are listed in a file arrangement table and the memory with the device at least temporarily connectable to the data communication, wherein an identifier can be generated, which is a state of the stored represented, wherein the identifier characterizes the file arrangement table, wherein the identifier of the device in a memory of the device is storable.

It is advantageous, in particular, if the identifier is identical to the file arrangement table or if the identifier is identified by means of a so-called HASH

Function is calculated from the file arrangement table.

According to one embodiment, it is advantageous if, due to a first switching on of the device for playing media data or after first connecting a memory to the device, the removable memory is searchable and meta-information of the files of the memory in a file or a local database of the device can be stored , Furthermore, it is expedient if, during a further activation of the device for playing media data or after reconnecting a memory with the device, the identifier stored in a memory of the device is comparable to an identifier newly calculated for the data stored on the replaceable memory are.

In a further embodiment, it is advantageous if, in the case of a match of the identifier stored in a memory of the device with a newly calculated identifier for the data stored on the removable memory, the metadata of the files of the removable memory stored on the memory of the device in a file or a local database are stored, usable for further applications.

In another embodiment, it is advantageous if, in a mismatch of the identifier stored in a memory of the device with a newly calculated identifier for the data stored on the replaceable memory, the metadata of the files of the replaceable memory are searchable again in a file or a local database of the device can be stored and the newly calculated identifier for the data stored on the removable memory in a memory of the device can be stored.

Further advantageous embodiments will be apparent from the dependent claims.

The invention will be explained in more detail on the basis of an embodiment with reference to the drawings. Show it:

Fig. 1 is a schematic representation of a device with a removable

Fig. 2 is a table showing a mapping file in which the data stored in the memory and the corresponding memory location are contained, and Fig. 3 is a block diagram for explaining the invention. FIG. 1 shows a device 1 for playing, for example, media data which is present as compressed media data on an exchangeable memory 2. For this purpose, the removable memory 2 can be designed to be connectable to the device 1, wherein the data on the memory 2 can be read out by the device 1 and / or browsed, inter alia, the data information, such as playing a piece of music and / or metadata of the respective at least one file or several or all files to read and possibly write in a related file, which can be used to view, for example, files of music pieces of a specially selected artist or play by title, artist, album, genre, etc. to sort and / or select. The device 1 can store this information in a file or database in an internal memory 8, on which it can later access, if necessary, also for other applications.

The various playable files or data optionally containing meta information are stored on the memory 2 and on the memory 2 or on the disk is still a so-called file arrangement table 3 before, also called File Allocation Table (FAT). Such a file arrangement table (FAT) is shown by way of example in FIG. This is an example

FAT table of a 128 MB USB memory, also called a stick, with a 16 bit FAT. The resulting file system is structured in clusters, which may have one or more sectors. Depending on the size of the memory, the number of clusters and / or sectors and thus the number of sectors for storing the structure information varies, so that some bytes of storage space are required to store the FAT file 3 itself. In such a system, the first sector is still the boot sector, typically followed by reserved sectors. Thereafter, the data arrangement table (FAT) is usually arranged.

The data arrangement table is unique for each data configuration in the memory, so that other data information also results in a different data arrangement table (FAT).

Column 4 lists a byte offset for various files listed by line. The byte offset thus provides a measure of the beginning of the file the memory. Column 5 indicates the length of the file. In column 6 a description of the file is given and in column 7 an example of a file arrangement of a FAT is given.

For example, adding the reserved sectors and the sectors used for the file arrangement table itself results in 255 sectors of 512 bytes, which corresponds to 131,072 bytes = 128 kB. This storage space would be needed to store the identifier for a given state of the memory, if that identifier is identical to the file arrangement table itself. Alternatively, the identifier can be retrieved from the file using a so-called HASH function.

Arrangement table are calculated. The result of such a HASH function also allows unambiguous identification of the file arrangement table, but is much smaller and therefore requires significantly less storage space in the memory of the device.

The inventive method provides that when a memory 2 is first connected to a corresponding device 1, the memory is searched with its files stored there and the meta information is read out. At the same time, the file arrangement table is read out in order to recognize in what state the memory with the files stored there is. For this purpose, according to the method, an identifier of the file arrangement table is generated, which characterizes the state of the memory and of the file arrangement table. This identifier is suitably stored on the memory of the device, for example in the form of a file.

If the memory with its files stored there is now connected to the device or if the device is started or switched on, then the identifier can first be retrieved from the memory and compared with an identifier previously stored in the device. In the event that the identifier has not changed, the meta-information stored in the device may continue to be used and a re-examination of the meta-information of the files of the memory is not necessary.

FIG. 3 shows an exemplary embodiment with reference to a block diagram 20. In block 21, the method is started. In block 22, the memory 2 is searched with its files stored there and the existing metadata there are stored in a file or database stored in a local memory of the device, see block 23.

At the same time, an identifier is formed in block 24 which uniquely characterizes the file arrangement table so that a change in the file arrangement table would be mandatory if a file is changed, deleted or added to the memory. This identifier is stored persistently in the internal memory of the device.

When the device is switched on again in block 25 or when the memory is connected to the device, the memory is not first searched for the meta-information, as in block 22, but it is compared whether the previously stored information (see block 24) is over If the identifier has remained the same so that it determines whether the data or files in the memory have changed or if the file arrangement table has changed, see block

26th

If there is no change in block 27, the previously determined meta-information in block 28 can continue to be used. Otherwise, a new lookup would be started at block 22 to determine the current data and meta information.

In block 29, the process is ended.

Claims

claims

1. A method for detecting media data on a removable storage medium or memory (2), wherein the media data are preferably stored with meta-information on the memory (2) as files, wherein the stored on the memory (2) files in a file array table

(3), characterized in that an identifier (24) is generated, which represents a state of the stored data, wherein the identifier characterizes the file arrangement table (3), wherein the identifier is stored in a memory of a device ,

2. The method of claim 1, wherein the identifier is identical to the file arrangement table (3).

3. The method according to claim 1, wherein the identifier is calculated using a so-called HASH function from the file arrangement table.

4. The method of claim 1, 2 or 3, characterized in that at a first switching on a device (1) for playing media data or after first connecting a memory (2) with such a device (1) the removable memory (2 ) is searched and

Meta information of the files of the memory are stored in a file or a local database of the device.

5. The method of claim 1, 2, 3 or 4, characterized in that in a further switching on a device (1) for playing media data or after reconnecting a memory (2) with such a device (1) in a Memory (8) of the device (1) stored identifier is compared with a re-calculated for the data stored on the removable memory (2) identifier.

6. The method according to claim 4 or 5, characterized in that in a match of the in a memory (8) of the device (1) stored identifier with a re-calculated for the data stored on the removable memory (2) identifier meta-information of the files the removable memory, which are stored on the memory of the device in a file or a local database, used for other applications.

7. The method of claim 4, 5 or 6, characterized in that in a mismatch of the stored in a memory (8) of the device (1) identifier with a re-calculated for the data stored on the removable memory (2) identifier meta-information the files of the removable memory (2) are re-searched, stored in a file or a local database of the device, and recalculated for the data stored on the removable memory (2)

Identifier is stored in a memory of the device.

8. Device, in particular for carrying out a method for detecting media data on a removable data carrier or memory (2), wherein the media data preferably with meta information on the memory (2) as

Files are stored, wherein the files stored on the memory (2) are listed in a file arrangement table (3) and the memory (2) with the device at least temporarily connectable to the data communication, characterized in that an identifier (24 ), which represents a state of the stored data, the identifier comprising the file

Arrangement table (3), wherein the identifier of the device in a memory (2) of the device is storable.

9. Device according to claim 8, characterized in that the identifier is identical to the file arrangement table (3) or the identifier is calculated by means of a so-called HASH function from the file arrangement table.

10. Apparatus according to claim 8 or 9, characterized in that due to a first switching on the device (1) for playing Media data or after first connecting a memory (2) with the device (1) the removable memory (2) is searchable and meta information of the files of the memory in a file or a local database of the device can be stored.

1 1. Apparatus according to claim 8, 9 or 10, characterized in that in a further switching on the device (1) for playing media data or after reconnecting a memory (2) with the device (1) in a memory (8) of Device (1) recalculated stored identifier with a data stored on the removable memory (2) data

Identifier are comparable.

12. The apparatus of claim 10 or 1 1, characterized in that in a match of the in a memory (8) of the device (1) stored identifier with a stored on the removable memory (2)

Data recalculated identifier meta-information of the files of the removable storage, which are stored on the memory of the device in a file or a local database, are usable for further applications.

13. The apparatus of claim 10, 1 1 or 12, characterized in that in a mismatch of in a memory (8) of the device (1) stored identifier with a for the on the removable memory (2) stored data newly calculated identifier the Meta-information of the files of the removable memory (2) are searchable again, in a file or a local database of the device can be stored and for the stored on the removable memory (2) newly calculated identifier in a memory of the device is stored.