Lossless Transform Audio Compression (LTAC) is a
compression algorithm developed by
Tilman Liebchen,
Marcus Purat and
Peter Noll at Institute for Telecommunications, Technical University
Berlin
Berlin is Capital of Germany, the capital and largest city of Germany, both by area and List of cities in Germany by population, by population. Its more than 3.85 million inhabitants make it the European Union's List of cities in the European U ...
(
TU Berlin
The Technical University of Berlin (official name both in English and german: link=no, Technische Universität Berlin, also known as TU Berlin and Berlin Institute of Technology) is a public research university located in Berlin, Germany. It was ...
),
[ to compress PCM audio in a ]lossless
Lossless compression is a class of data compression that allows the original data to be perfectly reconstructed from the compressed data with no loss of information. Lossless compression is possible because most real-world data exhibits statistic ...
manner, ''unlike'' conventional lossy
In information technology, lossy compression or irreversible compression is the class of data compression methods that uses inexact approximations and partial data discarding to represent the content. These techniques are used to reduce data size ...
audio compression algorithms (like MP3
MP3 (formally MPEG-1 Audio Layer III or MPEG-2 Audio Layer III) is a coding format for digital audio developed largely by the Fraunhofer Society in Germany, with support from other digital scientists in the United States and elsewhere. Orig ...
).
LTAC will not be developed any further since it has been superseded by its successor Lossless Predictive Audio Compression (LPAC), which is based on linear prediction
Linear prediction is a mathematical operation where future values of a discrete-time signal are estimated as a linear function of previous samples.
In digital signal processing, linear prediction is often called linear predictive coding (LPC) and ...
.[ This makes it much faster than LTAC and even leads to better compression results. LPAC has become official standard as MPEG-4 ]Audio Lossless Coding
MPEG-4 Audio Lossless Coding, also known as MPEG-4 ALS, is an extension to the MPEG-4 Part 3 audio standard to allow lossless audio compression. The extension was finalized in December 2005 and published as ISO/ IEC 14496-3:2005/Amd 2:2006 in 2 ...
.
See also
* Lossless Predictive Audio Compression (LPAC)
References
External links
Lossless Transform Coding (LTAC) of Audio Signals
{{Sound-tech-stub
Lossless audio codecs