WO2003017271A1

WO2003017271A1 - Method for exchanging and trading with data having a multimedia content

Info

Publication number: WO2003017271A1
Application number: PCT/DE2001/002937
Authority: WO
Inventors: Thomas Klotz; Gerhard Pehland; Robert Eiblmeier
Original assignee: Klotz-Digital Ag
Priority date: 2001-08-08
Filing date: 2001-08-08
Publication date: 2003-02-27
Also published as: DE10196767D2

Abstract

The invention relates to a method for supplying and extracting processed audio data to and from a network (2) e.g. the internet. The processed data is encoded in an encoding or decoding unit (7, 8), is stored in a database (14) of the network (12) (internet), and is only made accessible to interested people who are subscribers to the inventive method. The novel method for exchanging and trading multimedia digital data contents by means of a computer network (2) offers increased security against unauthorised access to the copyright protected data material of a database, and contributes significantly to reducing costs in favour of the user of the network (2).

Description

METHOD FOR EXCHANGING AND TRADING DATA WITH MULTIMEDIAL CONTENT

The present invention relates to a method for the secure exchange and trading of data with multimedia content in a computer network, in particular the Internet.

Such methods are known in the prior art from DE 196 25 635. This describes a method for encrypting multimedia files which have a determination data block and a multimedia data block. The identification data block contains an encryption index, which triggers an encryption algorithm and in turn enables the file to be activated. This known method is generally used to encrypt all types of Multimedia files. However, the method does not ensure that the data stream still has a validly readable data format that can be read by any commercial player, since the MPEG standard prescribes a specific arrangement of the data, which consists of repetitive file description blocks that have a standardized structure, consists. The structure of the data specified by the standard is destroyed. If the file modified in this way is then fed to an MPEG decoder, the decoder will issue an error message and will not carry out the work. A commercial player will therefore usually acknowledge an encrypted file with an error message according to the above procedure, unless the player has been specially designed for the procedure. Therefore, for the known method, a dedicated playback device that knows the encryption algorithm is always required, even to enable only a 20-second demonstration example. This player is then also a possible point of attack for circumventing the encryption, since the exemplary 20-second lock for the demonstration example in the player can be rendered ineffective with few means. It is also felt to be disadvantageous in the above-mentioned method that the customer's user ID is stored in the determination data block, which relates to the data in the administration area of the file.

Accordingly, multimedia data such as sound, images or video documents can be exchanged via computer networks. This can be done via a central server or by direct exchange between two computers. There is also a on the Internet Data exchange between participants is possible, such as via a central FTP server or directly via e-mail exchange. In addition, there is already the option of storing this data in central databases, which enable the database to be searched according to various criteria. Data reduction methods such as audio or video compression are often used. In the state of the art, all functions are implemented as pure software solutions for a wide variety of commercially available computer systems.

Furthermore, it is perceived as a disadvantage of this method that the security requirements with regard to copyright issues are not sufficiently taken into account in all cases.

The object of the present invention is therefore to improve the security of protected data when transferred to a network (Internet) and to simplify the economic management of protected data.

This object is achieved with the characterizing features of the main claim.

Further features essential to the invention can be found in the subclaims.

The method according to the invention for the exchange and trading of processed files with multimedia content in a network, for example the Internet, in which the processed data Different sources are distinguished by the fact that the data is subjected to encryption that is especially accessible for audio files, whereby validly readable audio signals are generated that contain an inaudible user identification (watermarking).

It has an advantageous effect here that the method according to the invention has a validly readable MPEG-ACC data stream which can be read and reproduced by any suitable commercial playback device. It is important that the process is specially tailored to audio files and generates validly readable ACC signals that can be reduced in sound quality when encrypted. In the method according to the invention, the quality restriction of the demonstration example is therefore contained in the audio signal itself, so that a simple modification of the playback device cannot lead to circumvention of the demonstration restrictions. A full signal can only be restored with the right key that the customer knows. In the demonstration example, there is no decryption at all. In other words, the method according to the invention makes use of the knowledge of physioacoustics, according to which the human ear is practically ignored other, quieter tones shortly before or after a very loud sound event. Also, the human ear does not perceive quieter tones of a similar pitch when the tone is very loud.

It is therefore advantageous that the user ID is embedded in the actual audio signal (watermarking), whereby the weaknesses of the human ear are used to impose information on the signal shortly before or after a loud sound that the human ear cannot perceive and thus subjectively do not perceive the change in the audio signal, and also insert information by inserting it into a Pitch that is missed due to a high volume tone. However, the physical content of this audio signal obtained in this way is retained and is recognized by the computer and made available for further use.

The so-called watermarking has the advantage that the user ID is still contained in the signal, even with analog dubbing on cassettes, with radio broadcasting or even with playback via loudspeaker and subsequent recording via microphone. In all of these cases, only the pure audio signal is present and the determination data block, as in the prior art, is no longer present. As a result of these measures according to the invention for audio files, at least the violation of copyrights is made more difficult and the pursuit is facilitated. In addition, the method according to the invention offers a higher security standard for audio files.

In this context, it is also advantageous that the method according to the invention provides to use special electronics which make it possible to process the files when they are decoupled from the network (Internet).

It is advantageous that the audio files in coded form with a reduced amount of data in the database of the network are fed in, the coding advantageously being carried out on the sender side and the decoding on the receiver side.

It is also advantageous to assign each participant in the method according to the invention an inaudible user identification (watermark) which is written into the audio signal in encrypted form by means of special software in the individual sender and receiver devices.

It is advantageous to transmit the encoded data in encrypted form, whereby pre-listening in reduced quality is made possible, which can be carried out without knowledge of the special key.

The transfer of audio and video content from and to the database is therefore data-reduced in order to be able to carry out the transfer more quickly and thus save costs. This requires encoders on the sender side and decoders on the receiver side. The participants in the method according to the invention can be identified via a unique, preset, and unchangeable user ID stored on the circuit of the special electronics, which ensures a considerable degree of data security. Since all audio files are encrypted at the request of the person who feeds the material into the database in such a way that other participants in the process can preview them in reduced quality without having the key to decrypt the files Data backup given. The reduced quality allows an impression of the content of the file without the file being usable in a professional environment. If desired, encryption can also take place in such a way that the content cannot be recognized at all without knowledge of the code. The coding and decoding takes place during the process in the special electronics and is controlled by the PC.

The encoding / decoding is based on a breakdown of the signal into different frequency components and volume information about these frequency ranges. The encryption is now based on the fact that these frequency ranges and volume information are interchanged, controlled by the secret code. The quality of the encrypted signal is reduced depending on how much frequency and level information is exchanged. Since the signal components are only interchanged, the end result remains a syntactically valid, but distorted signal that can be fed to the decoder. If there is no key, the signal is reproduced distorted, so that only the secret key ensures that the correct arrangement of the reversed frequency and level information is generated in the decoder and thus an undistorted signal for the user.

An audible identifier in the audio signal (watermark), which can be read out by special computer programs, enables the identification of both the sender and the recipient of an audio file. In this way, copyright infringements on protected files and unauthorized use of the data material can be recorded more easily. The labeling can during the encoding or decoding in the special electronics of the corresponding device. The inaudible identification (watermark) in the files is determined with the help of a computer program.

Senders can determine whether the content that is fed in should only be accessible to certain users, user groups or the general public. In addition, the sender can define criteria and attributes in his contribution that enable other users to quickly find the contribution in a targeted database search. The database makes it possible to search the content according to various criteria, taking into account the addressees entered by the sender. The sender can also mark or mark the file with a price so that the recipient can negotiate a price with him, the sender, before downloading a certain contribution (file), so that the file is only released when the price negotiated was paid.

Transactions between the individual participants in the method according to the invention which contain copyright-protected data material are recorded via an interface between the database and in a copyright management system.

In the following the invention will be described in more detail with reference to drawings. It shows Fig. 1 is a block diagram of the signal flow in the special electronics (1) during the audio encoding process

Fig. 2 is a block diagram showing the signal flow during the decoding process in the special electronics (l).

1 shows a block diagram from which the signal flow during the encoding process in the special electronics 1 emerges. The incoming data from the audio input 10 or the PCI interface 11 are supplied with the aid of the data controller 12 via an input selection 13 to the encoding and encryption unit 7, in which the data are encoded and encrypted with certain parameters which are assigned to them by the PCI interface 11 can be assigned. In this embodiment, the encrypted data are then fed to the watermarking unit (19), in which they receive a serial number from the corresponding unit 15 and the corresponding watermarking parameters from the PCI interface 11. The prepared data or files are then fed to the PCI interface 11, from where the further data stream into the network 2 to the database 14 is managed.

FIG. 2 shows a block diagram from which the signal flow during the decoding process in the special electronics unit 1 emerges. The data stream coming from the PCI interface 11 is first fed to the watermarking unit 19, which uses the serial number as the watermark communicated parameters from the PCI interface 11 and the serial number unit 15 in the audio signal and fed to the decoding and decryption unit 8. The data stream is then decrypted in the decoding unit 8 and the data reduction is reversed after the appropriate parameters have been communicated to it by the PCI interface 11. Following the decoding and decoding process in the decoding unit 8, the data stream is directly available to an audio output 16 (AES / EBU) and the interface 11, in which further administrative measures and data flow directions are determined. The database 14 is equipped with a copyright unit 17 and a payment transaction unit 18, in which the parameters necessary for the economic management of the data are stored and managed.

As a result of the combination of data reduction, encryption, clear identification of the participants and watermarking, the method according to the invention ensures improved security, in particular when transferring protected data through the comparatively insecure Internet.

Since the data is also stored encrypted in the system, there is also a relatively high level of security against malicious attacks on the database. State-of-the-art solutions can offer secure connections from the subscriber to the database, but store the data again in the database unencrypted. With a view to negotiating a price for a supporting program and ensuring that the price negotiated is paid electronically, it is essential to be able to preview a file in a cost-saving manner, which is done in reduced quality. Another important feature of the invention is the provision of an interface for the billing and recording of copyrighted data material.

In addition, special electronics 1, 1 adapted for the method according to the invention offer a much higher standard of data protection than a pure software solution, the individual software processes being interlinked, so that no intermediate files are formed which are transmitted, for example, unencrypted but with reduced data. As a result of the operating systems used, computer programs are frequently interrupted in their current execution by other processes on the computer, so that long waiting times arise. As a result of the use of software for the electronics 1, 1 ^{Λ which} is matched to the method according to the invention, an uninterrupted, predictable execution of the work in hand is ensured without being impaired by other computer processes.

Claims

13PATENTANSPRÜCHE

1. A method for exchanging and trading processed files with multimedia content in a network (2), for example the Internet, from which the data to be processed are taken from various sources (2, 6) and fed to a device (1, l ^λ ), which prepares the data and provides it with coding and encryption, and then feeds it to an external database (14), characterized in that the data are subjected to encryption which is specifically accessible for audio files, thereby producing the validly readable audio signals which have an inaudible user identification (watermarking ) contain.

2. The method according to claim 1, characterized in that the control and monitoring by means of special electronics (1, 1) and software in 14

PC (3) is made.

3. The method of claim 1, d a d u r c h g e k e n n z e i c h n e t that a control protocol is kept on the real-time control and the other processes.

4. The method according to any one of the preceding claims, that the entire special electronics (1, 1) are controlled in real time.

5. The method according to any one of the preceding claims, that the audio files are fed into the database (14) in the network (2) in coded form with a reduced amount of data.

6. The method according to any one of the preceding claims, that the coding (7) and encryption of the data is carried out on the sender side.

7. The method according to any one of the preceding claims, that the decoding (8) and decryption is carried out on the receiver side.

8. The method according to any one of the preceding claims, characterized in that the data are provided with an inaudible identifier (19) (watermark). 15

9. The method according to any one of the preceding claims, d a d u r c h g e k e n n z e i c h n e t that the encrypted data in reduced quality enable a preview, which can be carried out without knowledge of the code.

10. The method according to any one of the preceding claims, that the signals are divided into different frequency components and volume levels when encoding the data.

11. Method according to one of the preceding claims, that the different frequency components and volume levels are interchanged, the interchanging sequence being part of the key.

12. The method according to any one of the preceding claims, that the files stored in the external database (14) in the network (2) are only accessible to predetermined users.

13. The method as claimed in one of the preceding claims, that the files stored in the external database (14) receive digital price markings.

14. The method according to any one of the preceding claims, characterized in that the 16

The files are not released for decoding until a predetermined price has been paid.

15.The method according to any one of the preceding claims, that the transmission of all files containing data protected by copyright is carried out via an interface (11) with a management system.

16. according to one of the preceding claims, learn that each user of the method receives a user ID which is recognized by the software of the device (3).

17. The method according to any one of the preceding claims, that the database (14) is equipped with a copyright and payment transaction unit (17, 18).

18. The method according to any one of the preceding claims, d a d u r c h g e k e n n e e c h n e t that the validly readable MPEG-ACC signals contain a data quality restriction.

19. The method according to any one of the preceding claims, characterized in that the MPEG- ^' ACC data stream can be read by any suitable commercial player.