CN102012983A - Method and device for playing digital rights encryption protection technical file and mobile terminal - Google Patents

Abstract

The invention discloses a playing method, device and mobile terminal of digital copyright encryption protection technology files. The method includes: a reading step, reading a part of the digital copyright encryption protection technology DRM file; a decryption step, performing the reading on the read part Decryption; playing step, decoding and playing the decrypted part; looping from the reading step to the playing step, until the DRM file is stopped playing. The user experience is improved through the present invention.

Description

Playing method, device and mobile terminal of technical file of digital copyright encryption protection

technical field

The present invention relates to the communication field, in particular, to a playing method, device and mobile terminal for digital copyright encryption protection technology files.

Background technique

Digital rights encryption protection technology (Digital Rights Management, referred to as DRM) effectively solves the problem of how to control and charge users for downloading content and the use and dissemination of media after downloading. The basic working principle of DRM technology is as follows: the digital program authorization center uses a key to lock the media file. When the user orders, the user obtains the information of the authorization center from the media file and connects to obtain authorization. After passing the verification and authorization of the digital program authorization center, The playback is only allowed after the relevant key is sent for decryption.

OMA DRM is a DRM protocol developed by the Open Mobile Alliance (OMA) that can be applied to mobile communication terminals. OMA DRM specifies three DRM protection methods available on terminals.

First, the FL way. This method requires the terminal to restrict the forwarding of media files by the user. After the terminal obtains the media file, it can be freely and unrestrictedly used in the terminal. The terminal must protect the file from being forwarded to other devices through communication devices or mechanisms, including using infrared, Bluetooth, USB Universal Serial Bus (Universal Serial Bus, USB for short), external memory card, etc. In the FL mode, the authorization center is only responsible for sending media files, and the responsibility for protecting files lies with the specific terminal used by the user. Pay the copyright fee to the authorization center at the same time as the FL file is obtained.

Second, combined delivery (CD) mode. Compared with the FL method, the CD method will combine and package the media files and rights files in the authorization center. When a user uses a media file, the terminal software will query the permission object, and if the permission is met, it will play normally, otherwise it will prompt the user that the permission has expired. Same as the FL method, the user pays the copyright fee while obtaining the CD object. However, the CD mode is higher than the FL mode, that is, the terminal must protect the media files in the CD mode and cannot be forwarded by the user.

Third, separate transmission (SD) mode. The SD method is an improvement of the CD method. With the development of media content, the media object may be very large, and it may be very difficult to rely solely on the download of the mobile communication network. The SD method first encrypts the media file and packs it into a specific format (for example, DCF format), so that users can obtain it in various ways. The user does not need to pay for the process of obtaining media files. During use, the terminal software will first obtain the URL of the authorization center from the content in DCF format, start the browser to download the plaintext xml permission file containing the decryption key, and the user pays the corresponding fee to obtain different use permission restrictions during the download process of the permission file .

No matter which protection method is adopted, when the mobile terminal plays the DRM file, it must first judge the protection method, and then decrypt it before playing it. At present, the playback of DRM files on mobile terminals adopts the following playback methods:

One is to decrypt all the DRM files, store the plaintext files separately in a directory that ordinary users cannot see, and then store only the file name information in the directory that ordinary users can see (in fact, it is only for displaying file names to users. ), so that when the user plays, the software processes and directly plays the corresponding decrypted plaintext file, which is less secure.

Another way is to save the encrypted DRM file, and then play it after decrypting all the files during playback, and delete the plaintext file after playback, which is more secure.

However, as the size of the DRM file becomes larger, the user needs to wait for a long decryption time before playing no matter which playing method is mentioned above, thus affecting the user experience.

Contents of the invention

The main purpose of the present invention is to provide a method, device and mobile terminal for playing digital copyright encryption technology files, so as to at least solve the above problems.

According to one aspect of the present invention, a kind of playing method of digital copyright encryption protection technology file is provided, comprising: reading step, reads a part in the described digital copyright encryption protection technology DRM file; Decryption step, to the read The part is decrypted; the playing step is to decode and play the decrypted part; the reading step to the playing step are executed in a loop until the playing of the DRM file is stopped.

Preferably, reading a part of the DRM file includes: applying to read M bytes of data from the position of N bytes of the file to be played, wherein, the N and M are integers greater than or equal to zero; Describe whether the file that needs to be played is a DRM file; if the judgment result is yes, read the data of M bytes from the position of N+L bytes of the DRM file, wherein, the L is the data of the DRM file The byte length of the DRM information stored in the file header.

Preferably, reading a part of the DRM file includes: judging whether the file to be played is a DRM file, and reading a part of the DRM file if the judging result is yes.

Preferably, judging whether the file to be played is a DRM file, and reading a part of the DRM file when the judgment result is yes includes: judging whether the file to be played is a DRM file, and if the judgment result is yes, then Judging the validity of the DRM file, and reading a part of the DRM file if the DRM file is valid.

Preferably, the above method further includes: when the DRM file is invalid, prompting that the DRM file is invalid.

According to another aspect of the present invention, there is also provided a playback device for a digital copyright encryption protection technology file, including: a reading module for reading a part of the digital copyright encryption protection technology DRM file; a decryption module for For decrypting the read part; the playback module is used for decoding and playing the decrypted part; the calling module is used for circularly calling the reading module to the playing module until the DRM is stopped document.

Preferably, the reading module includes: an application module, which is used to apply for reading M bytes of data from the position of N bytes of the file to be played, wherein the N and M are integers greater than or equal to zero; A judging module, used to judge whether the file that needs to be played is a DRM file; a byte reading module, used to read M from the position of the N+L byte of the DRM file when the judgment result is yes bytes of data, wherein the L is the byte length of the DRM information stored in the file header of the DRM file.

Preferably, the reading module is configured to judge whether the file to be played is a DRM file, and read a part of the DRM file if the judgment result is yes.

Preferably, the reading module is used to judge whether the file to be played is a DRM file, if the judgment result is yes, then judge the validity of the DRM file, and read the DRM file if the DRM file is valid. part of the DRM file described above.

According to still another aspect of the present invention, a mobile terminal is also provided, including the above-mentioned device.

The present invention solves the problem of long waiting time for playing DRM in the prior art, thereby improving user experience.

Description of drawings

The accompanying drawings described here are used to provide a further understanding of the present invention and constitute a part of the application. The schematic embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute improper limitations to the present invention. In the attached picture:

Fig. 1 is the flowchart of the playing method of DRM file according to the embodiment of the present invention;

Fig. 2 is a structural block diagram of a device for playing a DRM file according to an embodiment of the present invention;

FIG. 3 is a structural block diagram of a reading module 22 according to an embodiment of the present invention;

Fig. 4 is a structural block diagram of a mobile terminal according to an embodiment of the present invention;

Fig. 5 is a flowchart of playing a DRM file according to a preferred embodiment of the present invention.

Detailed ways

Hereinafter, the present invention will be described in detail with reference to the drawings and examples. It should be noted that, in the case of no conflict, the embodiments in the present application and the features in the embodiments can be combined with each other.

Fig. 1 is the flow chart of the playing method of DRM file according to the embodiment of the present invention, as shown in Fig. 1, this flow process comprises the following steps:

Step S102, read a part of the DRM file;

Step S104, decrypting the read part;

Step S106, decoding and playing the decrypted part;

Steps S102 to S106 are executed in a loop until the DRM file is stopped playing.

Compared with the method in the prior art, where the entire DRM file is decrypted and then played, this embodiment adopts the method of decrypting a part and playing a part, thereby avoiding the need to wait for a long decryption time before playing in the prior art , improving the user experience.

The above steps utilize the following principles:

There is a file system on any mobile terminal system, and all media files will eventually be read when they are played, and the reading of the file when the media file is played is not to read the entire file into the memory at once, but to read a part of it. Decode one part and play one part. For the above reasons, according to the characteristics of DRM, the function of segmented decryption is realized (that is, to decrypt any part of the data of the DRM file to obtain the corresponding part), and then add this segment to the original file system to read the file system among.

Preferably, it can be judged in the reading of the file system, if it is a DRM file, then read and decrypt (the file header of the DRM file will store some DRM-related information, if its length is L, so it is really from N When reading M data at the location, you need to take the DRM header information into account, and finally read M bytes from N+L). If it is not a DRM file, just read it directly. Then decode and play.

Preferably, a judgment can be made before reading, that is, to judge whether the file to be played is a DRM file, and read a part of the DRM file if the judgment result is yes.

If the DRM file is valid, it can be judged whether the file to be played is a DRM file, if the judgment result is yes, then judge the validity of the DRM file, and read a part of the DRM file if the DRM file is valid . At this time, preferably, when the DRM file is invalid, a reminder of the invalidation of the DRM file can be performed.

Through above-mentioned preferred embodiment mode, upper-level software (or application) also needn't consider the problem of deciphering when realizing, after finishing for DRM file validity judgment, fully regard DRM as a common media file to play when really playing, deciphering work done in the file system.

Fig. 2 is the structural block diagram of the playing device of the DRM file according to the embodiment of the present invention, as shown in Fig. 2, this device comprises: reading module 22, deciphering module 24, playing module 26, calling module 28, to structure below Be explained.

The reading module 22 is used to read a part of the digital copyright encryption protection technology DRM file; the decryption module 24 is used to decrypt the read part; the playback module 26 is used to decode and play the part after the decryption ; The calling module 28 is used to call the reading module to the playing module in sequence in a loop until the DRM file is stopped playing.

Fig. 3 is the structural block diagram of reading module 22 according to the embodiment of the present invention, as shown in Fig. 3, this module comprises: application module 32, first judging module 34, byte reading module 36, this structure is carried out below illustrate.

Application module 32 is used to apply for reading the data of M bytes from the position of N bytes of the file that needs to be played, wherein N and M are integers greater than or equal to zero; the first judging module 34 is used to judge the files that need to be played. Whether the file is a DRM file; Byte reading module 36 is used to read the data of M bytes from the position of N+L bytes of the DRM file when the judgment result is yes, wherein, L is the file of the DRM file The byte length of the DRM information stored in the header.

Preferably, the reading module 22 is configured to judge whether the file to be played is a DRM file, and read a part of the DRM file if the judgment result is yes.

Preferably, the reading module 22 is used to judge whether the file to be played is a DRM file, if the judgment result is yes, then judge the validity of the DRM file, and read a part of the DRM file if the DRM file is valid.

In this embodiment, a mobile terminal is also provided, which includes the above-mentioned device. FIG. 4 is a structural block diagram of a mobile terminal according to an embodiment of the present invention. As shown in FIG. 4, the terminal may include a playback/display module, a file System (the function of reading module 22 is realized in this system), DRM decryption module (realizes the function of decryption module 24), file decoding module (this module and playing/display module have realized the function of playing module 26 together), these modules The functions of have been described above, and will not be repeated here.

The following will be described in combination with preferred embodiments.

In this embodiment, the judgment of the media file format can be carried out when the media file is played, and if it is a DRM file, then the judgment of validity is carried out, such as whether the number of times of playback is less than the maximum number of times of playback allowed, whether the playback time has not exceeded the allowed playback Time, etc., if these conditions are met, then play, first read a part of the source file during playback, then decrypt this part of the source file, then decode this part of the file, then play this part, then read, and then decrypt, Decode again and play again.

Fig. 5 is the flowchart of playing DRM file according to the preferred embodiment of the present invention, as shown in Fig. 5, this flow process comprises the following steps:

Step A. first judge whether the playback is a DRM media file, if so then go to B, if not then go directly to C;

Step B. Determine the validity of the DRM file (whether the number of times played has reached the maximum number of times allowed or the time allowed to play has expired, etc.), if valid, then run C, otherwise run J;

Step C. Apply to read data of M bytes from position N of the source file;

Step D. judge whether it is a DRM file, if it is to run E, otherwise run I directly;

Step E. Read M bytes of data from N+L of the source file. The header of the DRM file will store some DRM-related information. If its length is L, it is really necessary to read M bytes from N locations. For data, it is necessary to calculate the section of DRM header information, and finally start reading from N+L;

Step F. Decrypt the read M data according to the key, and restore the M byte source data;

Step G. Perform media decoding on the source data of M bytes;

Step H. The decoded data is played;

Step 1. directly read the data of M bytes from the file, and run G;

Step J. Prompt that the validity of the DRM is invalid.

Compared with the prior art, in the playing of the DRM file, this preferred embodiment utilizes the step of reading the file at last for all media file playing operations, realizes segmental decryption of the DRM file, realizes playing while decrypting, It completely solves the problem of safety and efficiency when playing DRM files.

Through the method of the above-mentioned embodiment and its preferred embodiment, a DRM file playback method that efficiently and safely plays while decrypting is provided. Compared with the existing technology, it ignores security (such as decrypting into a plaintext file before playing), or has high security, ignores efficiency, and affects user experience. Improve user experience and ensure the security of DRM files. In addition, the above-mentioned embodiment also achieves the reading and decryption of the DRM file by adding some judgments and reading operations to the DRM in the reading of the original non-DRM file. There is almost no impact on performance.

Obviously, those skilled in the art should understand that each module or each step of the above-mentioned present invention can be realized by a general-purpose computing device, and they can be concentrated on a single computing device, or distributed in a network formed by multiple computing devices Alternatively, they may be implemented in program code executable by a computing device so that they may be stored in a storage device to be executed by a computing device, and in some cases in an order different from that shown here The steps shown or described are carried out, or they are separately fabricated into individual integrated circuit modules, or multiple modules or steps among them are fabricated into a single integrated circuit module for implementation. As such, the present invention is not limited to any specific combination of hardware and software.

The above descriptions are only preferred embodiments of the present invention, and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and changes. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included within the protection scope of the present invention.

Claims (10)

1. the player method of a digital publishing rights encipherment protection technological document is characterized in that, comprising:

Read step reads the part in the described digital publishing rights encipherment protection technology DRM file;

Decryption step is decrypted the part that reads;

Play step, the part after the deciphering is decoded and play;

Circulation is carried out described read step to described broadcast step, up to stopping to play described DRM file.

2. method according to claim 1 is characterized in that, a part that reads in the described DRM file comprises:

The data of M byte are read in the position of the N byte of the file that application is play from needs, wherein, described N and M be greater than etc. zero integer;

Judge whether the described file that needs to play is the DRM file;

In judged result is the situation that is, reads the data of M byte from the position of the N+L byte of described DRM file, and wherein, described L is a byte length of depositing DRM information in the file header of described DRM file.

3. method according to claim 1 and 2 is characterized in that, a part that reads in the described DRM file comprises:

Judge whether the file that will play is the DRM file, and be a part that reads under the situation that is in the described DRM file in judged result.

4. method according to claim 1 and 2 is characterized in that, judges whether the file that will play is the DRM file, and is that a part that reads under the situation that is in the described DRM file comprises in judged result:

Judge whether the file that will play is the DRM file,, and under the effective situation of described DRM file, read a part in the described DRM file if judged result is then judged the validity of described DRM file for being.

5. method according to claim 4 is characterized in that, also comprises:

Under the situation that described DRM file lost efficacy, carry out the prompting that described DRM file lost efficacy.

6. the playing device of a digital publishing rights encipherment protection technological document is characterized in that, comprising:

Read module is used for reading the part of described digital publishing rights encipherment protection technology DRM file;

Deciphering module is used for the part that reads is decrypted;

Playing module is used for the part after the deciphering is decoded and play;

Calling module is used for circulation and calls described read module successively to described playing module, up to stopping to play described DRM file.

7. device according to claim 6 is characterized in that, described read module comprises:

The application module is used to apply for that the position of the N byte of the file play from needs reads the data of M byte, wherein, described N and M be greater than etc. zero integer;

First judge module is used to judge whether the file that described needs are play is the DRM file;

The byte read module, being used in judged result is the situation that is, reads the data of M byte from the position of the N+L byte of described DRM file, wherein, described L is a byte length of depositing DRM information in the file header of described DRM file.

8. device according to claim 6 is characterized in that,

Described read module is used to judge whether the file that will play is the DRM file, and is a part that reads under the situation that is in the described DRM file in judged result.

9. device according to claim 6 is characterized in that,

Described read module is used to judge whether the file that will play is the DRM file, if judged result is then judged the validity of described DRM file for being, and reads a part in the described DRM file under the effective situation of described DRM file.

10. a portable terminal is characterized in that, comprises each described device in the claim 6 to 9.

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