Fraunhofer-Gesellschaft Zur Foerderung Der Angewandten Forschung E.V.

Other

J&uuml;rgen Zeller

Heinz Gerh&auml;user

Martin Dietz

Harald Popp

Karlheinz Brandenburg

Oliver Kunz

Niels Rump

Rainer Buchta

Martin Sieler

A method for ciphering multimedia includes the entering of an ciphering index in a definition data block of the multimedia data, this index pointing to an ciphering algorithm which is to be used. In response to the ciphering index in the definition data block one of a plurality of ciphering algorithms is selected. The multimedia data are ciphered using the selected ciphering algorithm. Various additional entries in the definition data block which is assigned to the multimedia data permit the clearing or enabling of a deciphering device, rapid access to a database of ciphered multimedia data and a customer- and data-specific use of the multimedia data while taking copyright aspects into account.

Encryption and decryption of multi-media data

In a method for detecting a manipulation performed on digital information the erroneous determination of a manipulation during processing disturbances is prevented by subdividing the information into information subunits from each of which an identification is derived which is assigned to the respective information subunit. After processing the information subunits together with their identifications, potentially manipulated information subunits are determined on the basis of their identifications. This enables the whole of the information to be classified as manipulated if at least two information subunits which are correlated with respect to time or location have been determined to have been potentially manipulated.

Process for sensing manipulations of digital information

In a method for coding an audio signal digitized at a low sampling rate to obtain time domain audio samples. A frequency domain representation of the time domain audio samples is produced. The frequency domain representation includes successive frequency lines. These frequency lines are grouped into a plurality of scale factor bands. The successive frequency lines in a scale factor band are coded with the same scale factor. A plurality of regions is formed by grouping the scale factor bands, wherein successive scale factor bands form a region within which all the scale factors are coded with the same number of bits, which is determined according to the largest scale factor of the region. The scale factors assigned to scale factor bands within the highest region that includes the higher frequency successive frequency lines are set to zero. The frequency lines in the highest region are coded using the zero-valued scale factors that correspond to a multiplication factor of 1. The scale factors for the highest region, however, are not coded. Thus, the bits that would be required for coding these zero-valued scale factors are saved and can be used for a finer quantization of the rest of the spectrum. Additionally, this coding method when applied to ISO/IEC 13818-3 as a low sampling rate modification thereof only requires minimal changes with respect to this Standard.

Process of low sampling rate digital encoding of audio signals

Growing community of inventors

Ismaning, Germany

Jürgen Zeller

Growing community of inventors

Ismaning, Germany

J&uuml;rgen Zeller

Jürgen Zeller