KR20040075822A - Method for embedding/extracting additional data into/from asf file and file playback device - Google Patents

Abstract

PURPOSE: A method for inserting/extracting additional information into/from an ASF(Active Streaming Format) file and a file reproduction device are provided to distributively insert high-capacity data inside a data object of a file, thereby effectively using various additional information within a limited memory. CONSTITUTION: A system searches information on a file size by analyzing a header object of an original ASF file(S301). The system searches a size of padding data existing within a data object of the original ASF file(S302). The system converts a format of additional information(S303), and inserts the additional information from a starting point of the padding data in data packet unit for a data object of a new ASF file(S304). The system modifies the entire padding data by reflecting the searched information to prevent the new ASF file from being troubled(S305). The system generates a new ASF file added with the additional information.

Description

METHOD FOR EMBEDDING / EXTRACTING ADDITIONAL DATA INTO / FROM ASF FILE AND FILE PLAYBACK DEVICE}

The present invention relates to a method for inserting and extracting additional information into / from an ASF (Active Streaming Format) file and a file reproducing apparatus. Specifically, a method for distributing and extracting additional information into a data object of an ASF file and extracting the same. And a file reproducing apparatus.

Among the file formats widely used by the general public, the ASF file format developed by Microsoft is a kind of multimedia data format designed to include most multimedia data such as images, audio, and video.

A method for recording various additional data associated with a file in this file format has been proposed. However, this conventional method of recording additional information is a method in which additional information that requires a lot of memory is gathered into one object at the beginning or the end of the file. Only information was available.

Hereinafter, the structure of an ASF file will be described with reference to FIG. 1.

1 is a structural diagram showing the configuration of an ASF file.

As shown in FIG. 1, the format of an ASF file is roughly divided into a header object (101), a data object (102) and another object (103). The header object 101 includes basic information about a file, information on a sampling frequency, a compression type, a bit rate, and the like necessary for reproduction. This series of information is in turn composed of several objects.

Meanwhile, in the related art, additional information related to contents included in the file, for example, a singer name, a song name, a genre, and the like, in the case of a music file, is irrelevant to the reproduction of the file. Included.

In other words, conventionally, various additional information has been inserted into the header object 101 to more faithfully describe a file. Therefore, in order to use such additional information while playing a file in the portable playback device, the additional information may be stored in the memory before the file is played back.

However, if you want to view the lyrics of the music while you are listening to a music file created in the ASF file format on a portable playback device, or if you want to display the image of the singer who sings the song, if such additional information is present at the beginning of the file, Each additional information to be output can be saved only by allocating a buffer in memory before playing the file. Therefore, if the memory is severe and there is no spare memory, the additional information is portable even if the file contains the additional information. There is a problem that such an implementation itself becomes difficult in a playback device.

That is, since related data exist at the front or the end of the file, there is a problem that all such data cannot be utilized during file playback.

The present invention proposes a configuration in which such additional information is distributed and inserted in the data object in order to solve the problems of the related art. Accordingly, the additional information can be efficiently output without burden of memory capacity during music playback. have.

SUMMARY OF THE INVENTION An object of the present invention is to provide a data object of a file with a large amount of additional data required during reproduction of a file, especially large data that is required when the ASF file is located in front of or behind a file. It is to provide a method and an apparatus which can utilize various additional information within a limited memory during reproduction in a portable reproducing apparatus by distributedly inserting into the inside.

Another object of the present invention is that the insertion of the additional information does not cause any problem in the reproduction of the file, and in a portable playback device capable of playing ASF files including a general personal computer, the inserted additional information is detected during playback and various It is to provide a method and apparatus that can be utilized in the form.

1 is a structural diagram showing the configuration of an ASF file.

2 is a structural diagram of a data packet constituting a data object among the basic structures of an ASF file.

3 is a flowchart of a method of inserting additional information into an ASF file according to the present invention.

4 is a structural example of additional information to be inserted.

5 is a flowchart of a method of extracting additional information from an ASF file according to the present invention.

* Explanation of symbols for the main parts of the drawings

101: header object 102: data object

102a to 102m: data packet 103: other objects

201: Error correction data 202: Payload analysis information

203: payload data 204: padding data

401: additional information header 402: additional information

In order to achieve the above object, the present invention provides a method of inserting additional information into an ASF file, and distributes and inserts additional information into a data object in the ASF file.

Preferably, the additional information is inserted into the padding data area of each data packet in the data object.

Also preferably, when the additional information is inserted, a corresponding additional information header is inserted together.

Also preferably, the additional information includes one or more of subtitles, lyrics, or image data.

Also preferably, the additional information insertion method may include: a file information analyzing step of analyzing predetermined file information through a header object of an ASF file; A data packet analysis step of analyzing the data packet in the data object of the ASF file to analyze information including the size of the padding data; An additional information insertion step of inserting insertion target additional information into the padding data area in units of the respective data packets; And a file information resetting step of resetting the predetermined file information in the header object with respect to the change of the padding data area due to the insertion of the additional information.

Also, preferably, the predetermined file information in the file information analyzing step includes size information of the ASF file, size information of the data object, size information of the data packet, and size information of the padding data.

In order to achieve the above object, the present invention provides a method for extracting additional information from an ASF file, comprising: (a) extracting additional information from a data object area in an ASF file; And (b) using the extracted additional information.

Preferably, in step (a), the additional information is extracted in the padding data area of each data packet in the data object.

Also preferably, between step (a) and step (b), the additional information header is also extracted from the padding data area, and the validity of the additional information header is determined so that the next data packet is not valid if the additional information header is not valid. (a) further comprising the step of performing.

In order to achieve the object as described above, the present invention provides a file reproducing apparatus having means for extracting additional information from a data object area in an ASF file.

Preferably, the extracting means extracts additional information in the padding data area of each data packet in the data object.

Also preferably, the file reproducing apparatus is a portable reproducing apparatus.

Also preferably, the file reproducing apparatus is an MP3 player.

Hereinafter, a method and a file reproducing apparatus for inserting / extracting additional information into / from an ASF file according to the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 shows a structural diagram showing the structure of a conventional ASF file. The present invention can efficiently insert or extract additional information while maintaining the structure of an ASF file while being compatible with a conventional reproducing apparatus.

Since portable playback devices use very limited resources, it is impossible to utilize them during playback if the additional information varies and the size is beyond the size of the resources. For example, in the case of an ASF file containing music, if the lyrics of the song, the album photo or the singer photo have been inserted in the header object 101, the lyrics of the song can be output in order to properly output the lyrics to the LCD of the portable playback device during playback. It is possible to save all the files. The same is true when you want to play back multiple images on the LCD.

Of course, it is also possible to store the additional information as a separate file and then output it. However, when the file is present in multiple files, it becomes difficult to recognize and manage which file is related to the ASF file. Moreover, when there are dozens of ASF files, it becomes difficult to know which file should be linked to which file.

Therefore, the additional information required during the reproduction of the file must be in the data object 102 rather than the header object 101 so that the additional information can be easily obtained during the reproduction, and it is possible to output the obtained additional information to the LCD with a certain amount of resources. do.

For example, when lyrics or image data are distributed and inserted in the data object 102, additional information detected during playback of the file may be immediately output to the LCD, and the additional information may be used to change the sound quality and automatically adjust the volume. It can also be used for change. If the lyrics data is inserted as additional information, it is not necessary to store a large amount of data in advance because the detected lyrics data can be output directly on the screen.

Hereinafter, with reference to FIG. 2, the structure of the ASF data packet which comprises the data object 102 shown in FIG. 1 is demonstrated in detail.

2 is a structural diagram of a data packet constituting a data object among the basic structures of an ASF file.

Data object 102 is composed of a plurality of consecutive data packets 102a through 102m. In the actual file playback process, a predetermined data packet is read from the file, and then the payload data included in the data packet is decompressed to play the file. Therefore, when the additional information is included in the data packet according to the present invention, the additional information can be sequentially loaded according to the reproduction time while playing the file, and various additional information can be utilized simultaneously with the reproduction.

The data packets 102a-102m include error correction data 201, payload parsing information 202, payload data 203, and padding data 204. It includes. Here, since the error correction data 201 and the payload data 203 contain multimedia data, it is impossible to change the data or change the size thereof. However, since the padding data 204 is a separate space from the reproduction of the file, even if the external additional information is included in the present invention, the reproduction of the file is not affected.

Therefore, in accordance with the present invention, the use of the padding data 204 space enables insertion of additional information. However, since the padding data 204 does not allocate much space in the data packets 102a to 102m, there is generally only about 2 to 4 bytes of space per data packet 102a to 102m. Therefore, since the user cannot put all of the additional information desired by the user in the padding data 204 space originally present in the ASF file, it is possible to increase the padding data 204 space in order to insert various additional information.

Since the ASF file is a file format including various multimedia data, both the size of the data packets 102a to 102m and the information about the size of the padding data 204 are specified in the header object 101, and accordingly, according to the present invention, When the padding data 204 is added to insert additional information, all the information of the file related to this information must be found and set to the changed value so that playback of the file does not occur.

3 and 4, a method of inserting additional information into the padding data 204 region will be described.

3 is a flowchart of a method for inserting additional information into a file according to the present invention, and FIG. 4 is a configuration example of additional information to be inserted.

Referring to Fig. 3, through analysis of the original ASF file information (step S301), the header object 101 of the original ASF file is analyzed to record the information on the size of the file, the location of the data object 102 of the original ASF file. The location where the information on the size is recorded, the location where the information about the size of the unit data packets 102a to 102m of the original ASF file is recorded, and the location where the information about the size of the padding data 204 of the original ASF file is recorded are recorded in the file. Find. All objects before the data object 102 of the original ASF file are stored in the new ASF file as they are.

In the data packet analysis of the original ASF file (step S302), the configuration of the data packets 102a to 102m existing in the data object 102 of the original ASF file is found, particularly the size of the padding data 204. Once, one data packet is written to the new ASF file.

The following is a step of converting the format of the additional information (step S303). If the additional information of the original ASF file is simply divided into appropriate sizes and put into the padding data 204 space, i.e., if only the additional information is inserted, the meaning of the information in the padding data space of the new ASF file can be easily identified later. A problem arises that is missing. Therefore, in consideration of this, as shown in FIG. 4, a separate side information header 401 for the side information is created so that the padding data area of the new ASF file is composed of the side information header 401 and the actual side information 402. do. The information that the additional information header 401 can include is all or part of information, such as, for example, data type, data length, start or continuation of the data. The additional information 402 may include, for example, lyrics, images, equalizers, volumes, and the like, which may correspond to all or part of other information that a user wants to utilize during file playback. The above information corresponding to the additional information header 401 and the additional information 402 is merely exemplary, and other information may be included as necessary. As a precondition for making the structure as shown in Fig. 4, the step including the generation of the additional information header 401 is the additional information format conversion step (step S303).

Step S303 is not necessarily subsequent to steps S301 and S302. It is sufficient that step S303 is performed at any point before step S304 is performed.

In the additional information insertion step (step S304), the additional information to be inserted is inserted from the start position of the padding data 204 in units of each data packet 102a to 102m in the data object 102 of the new ASF file. In this case, the additional information may be inserted into the padding data 204 included in one or more data packets 102a to 102m according to their size. The additional information insertion (step S304) does not merely insert additional information as it is, but uses the additional information header 401 obtained in step S303 to add the additional information header 401 to the padding data 204 portion of the new file. Allow additional information 402 to be included. In this manner, the desired additional information is inserted into all the data packets 102a to 102m, and then a new ASF file is repeatedly stored.

In this case, the additional information to be inserted may be identified as additional information in the padding data 204 region of the new ASF file, and may be inserted in a form having a structural feature as shown in FIG. 4 so as to distinguish the type of information among the additional information. do. If this structure is not used, it is difficult to identify what data is detected later, and it may be difficult to obtain only the additional information 402 in the padding data 204 area.

That is, when information inserted in the padding data 204 of the new ASF file is detected, it is determined whether the type, length, and additional information of the inserted data are to be started, continuous, or ended to effectively combine them into one piece of information. Information, such as a classification code, that is, an additional information header 401 may be inserted.

Inserting the additional information 402 increases the size of the padding data 204 defined in the original ASF file, thus changing the size of the entire file. Therefore, the total sum of the padding data size 204 increased while inserting the additional information 402 should be recorded. The increase in padding data 204 affects the size of the entire file, the size of the data object 102, the size of the unit data packets 102a-102m, the maximum / minimum size of the unit padding data 204, and so on. This is because the information needs to be modified last so that the file does not have any problem playing.

In this case, to smoothly increase the padding data 204 and simplify the calculation, it is desirable to fix the maximum size of the padding data 204 of the new ASF file. Data packet analysis (step S302) and additional information insertion (step S304) are repeatedly processed from the first data packet 102a to the last data packet 102m of the data object 102, and the total increased padding data 204 size Record the values and the maximum and minimum sizes of padding data 204.

In the file information resetting (step S305), the entire padding data 204 increased in units of data packets is found, information on the file size found through the file information analysis step (step S301), information on the size of the data object 102, The information on the size of the data packet, the information on the size of the padding data 204, and the like are reflected to correct the problem so that the playback of the new ASF file does not occur.

Through all the steps of FIG. 3, a new ASF file is created in which additional information is inserted into the original ASF file. The newly created ASF file can be played normally even in the existing ASF file playing program or (portable) playing device, and additional information can be used while playing the file when a device for extracting additional information is mounted separately. .

Hereinafter, a method of extracting additional information inserted by the above-described method will be described with reference to FIG. 5.

5 is a flowchart of a method of extracting additional information from an ASF file of the present invention.

The method of extracting the additional information distributed and inserted in the ASF file can be made much simpler than the insertion process.

A file whose size of padding data 204 into which additional information can be inserted is changed is indistinguishable from a general ASF file. This is because all formats comply with the existing ASF file format. A method of extracting additional information proceeds by sequentially reading data of a new ASF file from a PC or a portable playback device in order to reproduce a new ASF file.

First, the padding data 204 in the data packet is read in data packet units (step S501). Since the additional information 402 is inserted in units of data packets constituting the data object 102 of the new ASF file, when the data packet is read from the file, the padding data 204 present in the data packet may be read and processed.

Thereafter, the validity of the additional information header 401 is determined (step S502). If the additional information header 401 is not valid, the additional information header 401 is not additional information inserted by the user. That is, the flow returns to step S501 to read the padding data 204 of the 'next' data packet. If the additional information header 401 is valid, the flow advances to step S503.

The next step is to analyze the type of the additional information 402 to determine whether it is the desired additional information 402 (step S503). Since the additional information 402 inserted into the padding data 204 of the new ASF file includes the additional information header 401 as shown in FIG. 4, the padding data 204 currently read by analyzing the information of the additional information header 401. ) Determines what kind of additional information 402 is used, and extracts and uses the inserted additional information 402, or moves to the next packet without extracting the additional information 402 that is not desired. That is, in the case of the desired additional information 402, the process proceeds to step S504 to use the inserted additional information 402. If the desired additional information 402 is not the desired additional information 402, the control returns to step S501 and the padding data of the 'next' data packet ( 204).

Also, since various additional information 402 is inserted in the padding data 204, the additional information header 401 may be analyzed to classify and obtain information to be detected.

In addition, it is determined whether all the additional information is extracted (step S505). If all of the additional information is extracted, the extraction process is terminated. If all of the additional information is not extracted, the above steps are repeated from step S501.

On the other hand, a file reproduction apparatus for extracting additional information from an ASF file using the additional information extraction method of the present invention in FIG. 5 described above is also included in the scope of the present invention. Such a file reproducing apparatus may be an MP3 player.

In the memory of the file reproducing apparatus, a program for allowing the CPU to perform the method of extracting the additional information according to the present invention may be stored, or the functional means of the method of extracting the additional information described with reference to FIG. It may be included in the file reproducing apparatus as a software module.

The present invention distributes and inserts a large amount of additional information into an ASF file so that various additional information can be utilized during playback. When using this method or device, even in a portable playback device, various and large amounts of additional information related to ASF files can be easily utilized during file playback.

The existing ASF file solves the problem of using a lot of memory, which is a problem in the method of recording additional information provided, so that the lyrics, album image, singer's personal information, etc. are needed during file playback with only a small memory space and resources. Make it available properly.

Although the invention has been particularly shown and described with reference to the above embodiments, it has been used only for the purpose of illustration and those of ordinary skill in the art to which the invention pertains may have as defined in the appended claims. It should be understood that various modifications may be made without departing from the spirit and scope.

Claims (13)

As a method of inserting additional information into an ASF file, And inserting the additional information distributed in a data object in the ASF file. The method of claim 1, And inserting the additional information into a padding data area of each data packet in the data object. The method according to claim 1 or 2, When the additional information is inserted, a corresponding additional information header is inserted together. The method according to claim 1 or 2, And the additional information includes one or more of subtitles, lyrics, or image data. The method of claim 1, The method, a file information analyzing step of analyzing predetermined file information through a header object of the ASF file; (b) a data packet analysis step of analyzing data packets in the data object of the ASF file to analyze information including the size of padding data; (c) an additional information insertion step of inserting insertion target additional information into the padding data area in units of the respective data packets; And and (d) a file information resetting step of resetting the predetermined file information in the head object with respect to the change in the padding data area due to the insertion of the additional information. The method of claim 5, wherein The predetermined file information in the step (a), And size information of the ASF file, size information of the data object, size information of the data packet, and size information of the padding data. A method of extracting additional information from an ASF file. (a) extracting the additional information from a data object area in the ASF file; And (b) using the extracted additional information. The method of claim 7, wherein In the step (a), the additional information is extracted in the padding data area of each data packet in the data object. The method of claim 8, Between step (a) and step (b), Further extracting an additional information header from the padding data area, determining the validity of the additional information header, and performing step (a) on a next data packet if the additional information header is not valid; Additional Information Extraction Method. And means for extracting additional information from the data object area in the ASF file. The method of claim 10, And said extracting means extracts said additional information from the padding data area of each data packet in said data object. The method of claim 10 or 11, And the file reproducing apparatus is a portable reproducing apparatus. The method of claim 10 or 11, And the file reproducing apparatus is an MP3 player.