Patent application number | Description | Published |
20090003612 | Compatible Multi-Channel Coding/Decoding - In processing a multi-channel audio signal having at least three original channels, a first downmix channel and a second downmix channel are provided, which are derived from the original channels. For a selected original channel of the original channels, channel side information are calculated such that a downmix channel or a combined downmix channel including the first and the second downmix channels, when weighted using the channel side information, results in an approximation of the selected original channel. The channel side information and the first and second downmix channels form output data to be transmitted to a decoder, which, in case of a low level decoder only decodes the first and second downmix channels or, in case of a high level decoder provides a full multi-channel audio signal based on the downmix channels and the channel side information. Since the channel side information only occupy a low number of bits, and since the decoder does not use dematrixing, an efficient and high quality multi-channel extension for stereo players and enhanced multi-channel players is obtained. | 01-01-2009 |
20100161319 | DEVICE AND METHOD FOR GENERATING A COMPLEX SPECTRAL REPRESENTATION OF A DISCRETE-TIME SIGNAL - A filter bank device for generating a complex spectral representation of a discrete-time signal includes a generator for generating a block-wise real spectral representation, which, for example, implements an MDCT, to obtain temporally successive blocks of real spectral coefficients. The output values of this spectral conversion device are fed to a post-processor for post-processing the block-wise real spectral representation to obtain an approximated complex spectral representation having successive blocks, each block having a set of complex approximated spectral coefficients, wherein a complex approximated spectral coefficient can be represented by a first partial spectral coefficient and by a second partial spectral coefficient, wherein at least one of the first and second partial spectral coefficients is determined by combining at least two real spectral coefficients. A good approximation for a complex spectral representation of the discrete-time signal is obtained by combining two real spectral coefficients, preferably by a weighted linear combination, wherein additionally more degrees of freedom for optimizing the entire system are available. | 06-24-2010 |
20110170711 | Audio Encoder, Audio Decoder, Methods for Encoding and Decoding an Audio Signal, and a Computer Program - An encoder for providing an audio stream on the basis of a transform-domain representation of an input audio signal includes a quantization error calculator configured to determine a multi-band quantization error over a plurality of frequency bands of the input audio signal for which separate band gain information is available. The encoder also includes an audio stream provider for providing the audio stream such that the audio stream includes information describing an audio content of the frequency bands and information describing the multi-band quantization error. | 07-14-2011 |
20110173007 | Audio Encoder and Audio Decoder - An audio encoder for encoding segments of coefficients, the segments of coefficients representing different time or frequency resolutions of a sampled audio signal, the audio encoder including a processor for deriving a coding context for a currently encoded coefficient of a current segment based on a previously encoded coefficient of a previous segment, the previously encoded coefficient representing a different time or frequency resolution than the currently encoded coefficient. The audio encoder further includes an entropy encoder for entropy encoding the current coefficient based on the coding context to obtain an encoded audio stream. | 07-14-2011 |
20110173012 | Noise Filler, Noise Filling Parameter Calculator Encoded Audio Signal Representation, Methods and Computer Program - A noise filler for providing a noise-filled spectral representation of an audio signal on the basis of an input spectral representation of the audio signal has a spectral region identifier configured to identify spectral regions of the input spectral representation spaced from non-zero spectral regions of the input spectral representation by at least one intermediate spectral region, to obtain identified spectral regions, and a noise inserter configured to selectively introduce noise into the identified spectral regions to obtain the noise-filled spectral representation of the audio signal. A noise filling parameter calculator for providing a noise filling parameter on the basis of a quantized spectral representation of an audio signal has a spectral region identifier, as mentioned above, and a noise value calculator configured to selectively consider quantization errors of the identified spectral regions for a calculation of the noise filling parameter. Accordingly, an encoded audio signal representation representing the audio signal can be obtained. | 07-14-2011 |
20110200198 | Low Bitrate Audio Encoding/Decoding Scheme with Common Preprocessing - An audio encoder has a common preprocessing stage, an information sink based encoding branch such as spectral domain encoding branch, a information source based encoding branch such as an LPC-domain encoding branch and a switch for switching between these branches at inputs into these branches or outputs of these branches controlled by a decision stage. An audio decoder has a spectral domain decoding branch, an LPC-domain decoding branch, one or more switches for switching between the branches and a common post-processing stage for post-processing a time-domain audio signal for obtaining a post-processed audio signal. | 08-18-2011 |
20110202354 | Low Bitrate Audio Encoding/Decoding Scheme Having Cascaded Switches - An audio encoder has a first information sink oriented encoding branch such as a spectral domain encoding branch, a second information source or SNR oriented encoding branch such as an LPC-domain encoding branch, and a switch for switching between the first encoding branch and the second encoding branch, wherein the second encoding branch has a converter into a specific domain different from the spectral domain such as an LPC analysis stage generating an excitation signal, and wherein the second encoding branch furthermore has a specific domain coding branch such as LPC domain processing branch, and a specific spectral domain coding branch such as LPC spectral domain processing branch, and an additional switch for switching between the specific domain coding branch and the specific spectral domain coding branch. An audio decoder has a first domain decoder such as a spectral domain decoding branch, a second domain decoder such as an LPC domain decoding branch for decoding a signal such as an excitation signal in the second domain, and a third domain decoder such as an LPC-spectral decoder branch and two cascaded switches for switching between the decoders. | 08-18-2011 |
20110202355 | Audio Encoding/Decoding Scheme Having a Switchable Bypass - An apparatus for encoding includes a first domain converter, a switchable bypass, a second domain converter, a first processor and a second processor to obtain an encoded audio signal having different signal portions represented by coded data in different domains, which have been coded by different coding algorithms. Corresponding decoding stages in the decoder together with a bypass for bypassing a domain converter allow the generation of a decoded audio signal with high quality and low bit rate. | 08-18-2011 |
20110282471 | Apparatus and Method for Synchronizing Additional Data and Base Data - For adding additional data, such as multi-channel extension data, to base data, such as conventional stereo data, a test fingerprint of test data relating to a test time instant of the test data is provided. The test data equals the additional data or the base data or depends on the additional data or the base data in parametric manner. Using the test fingerprint, reference time instant information is determined, which depends on a reference time instant in reference data, the reference data being the conventional stereo data. Finally, the additional data or the base data is manipulated, namely using the reference time instant information and the test time instant information, to obtain manipulated data, by which synchronous reproduction of the data information can be performed. Thus, a robust and flexible possibility for synchronous, especially late extension of base data by additional data is obtained. | 11-17-2011 |
20120195434 | DEVICE AND METHOD FOR GENERATING AN AMBIENCE SIGNAL - A transient detector is provided for generating an ambience signal suitable for being emitted via loudspeakers for which there is no special loudspeaker signal to detect a transient period. A synthesis signal generator produces a synthesis signal which fulfils the transient condition on the one hand and the continuity condition for the synthesis signal on the other hand. A signal substituter will then substitute a portion of the examination signal by the synthesis signal to obtain an ambience signal for the surround channels. | 08-02-2012 |
20130066640 | AUDIO ENCODING/DECODING SCHEME HAVING A SWITCHABLE BYPASS - An apparatus for encoding includes a first domain converter, a switchable bypass, a second domain converter, a first processor and a second processor to obtain an encoded audio signal having different signal portions represented by coded data in different domains, which have been coded by different coding algorithms. Corresponding decoding stages in the decoder together with a bypass for bypassing a domain converter allow the generation of a decoded audio signal with high quality and low bit rate. | 03-14-2013 |
20130282389 | ENCODER, DECODER AND METHODS FOR ENCODING AND DECODING DATA SEGMENTS REPRESENTING A TIME-DOMAIN DATA STREAM - An apparatus for decoding data segments representing a time-domain data stream, a data segment being encoded in the time domain or in the frequency domain, a data segment being encoded in the frequency domain having successive blocks of data representing successive and overlapping blocks of time-domain data samples. The apparatus includes a time-domain decoder for decoding a data segment being encoded in the time domain and a processor for processing the data segment being encoded in the frequency domain and output data of the time-domain decoder to obtain overlapping time-domain data blocks. The apparatus further includes an overlap/add-combiner for combining the overlapping time-domain data blocks to obtain a decoded data segment of the time-domain data stream. | 10-24-2013 |
20140222442 | ENCODER, DECODER AND METHODS FOR ENCODING AND DECODING DATA SEGMENTS REPRESENTING A TIME-DOMAIN DATA STREAM - An apparatus for decoding data segments representing a time-domain data stream, a data segment being encoded in the time domain or in the frequency domain, a data segment being encoded in the frequency domain having successive blocks of data representing successive and overlapping blocks of time-domain data samples. The apparatus includes a time-domain decoder for decoding a data segment being encoded in the time domain and a processor for processing the data segment being encoded in the frequency domain and output data of the time-domain decoder to obtain overlapping time-domain data blocks. The apparatus further includes an overlap/add-combiner for combining the overlapping time-domain data blocks to obtain a decoded data segment of the time-domain data stream. | 08-07-2014 |
20140236605 | AUDIO ENCODER, AUDIO DECODER, METHODS FOR ENCODING AND DECODING AN AUDIO SIGNAL, AND A COMPUTER PROGRAM - An encoder for providing an audio stream on the basis of a transform-domain representation of an input audio signal includes a quantization error calculator configured to determine a multi-band quantization error over a plurality of frequency bands of the input audio signal for which separate band gain information is available. The encoder also includes an audio stream provider for providing the audio stream such that the audio stream includes information describing an audio content of the frequency bands and information describing the multi-band quantization error. | 08-21-2014 |
20140297293 | APPARATUS, METHOD AND COMPUTER PROGRAM FOR AVOIDING CLIPPING ARTEFACTS - An audio encoding apparatus includes an encoder for encoding a time segment of an input audio signal to be encoded to obtain a corresponding encoded signal segment. The audio encoding apparatus further includes a decoder for decoding the encoded signal segment to obtain a re-decoded signal segment. A clipping detector is provided for analyzing the re-decoded signal segment with respect to at least one of an actual signal clipping or an perceptible signal clipping and for generating a corresponding clipping alert. The encoder is further configured to again encode the time segment of the audio signal with at least one modified encoding parameter resulting in a reduced clipping probability in response to the clipping alert. | 10-02-2014 |