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Advanced Audio Coding

Advanced Audio Coding is an audio coding standard for lossy digital audio compression. Designed to be the successor of the MP3 format, AAC achieves higher sound quality than MP3 at the same bit rate. AAC has been standardized as part of the MPEG-2 and MPEG-4 specifications. Part of AAC, HE-AAC, is part of MPEG-4 Audio and adopted into digital radio standards DAB+ and Digital Radio Mondiale, as well as mobile television standards DVB-H and ATSC-M/H. AAC supports inclusion of 48 full-bandwidth audio channels in one stream plus 16 low frequency effects channels, up to 16 "coupling" or dialog channels, up to 16 data streams; the quality for stereo is satisfactory to modest requirements at 96 kbit/s in joint stereo mode. Tests of MPEG-4 audio have shown that AAC meets the requirements referred to as "transparent" for the ITU at 128 kbit/s for stereo, 320 kbit/s for 5.1 audio. AAC uses a purely modified discrete cosine transform algorithm, giving it higher compression efficiency than MP3, which uses a hybrid coding algorithm, part MDCT and part FFT.

AAC is the default or standard audio format for iPhone, iPod, iPad, Nintendo DSi, Nintendo 3DS, iTunes, DivX Plus Web Player, PlayStation 3 and various Nokia Series 40 phones. It is supported on PlayStation Vita, Sony Walkman MP3 series and Android and BlackBerry. AAC is supported by manufacturers of in-dash car audio systems; the discrete cosine transform, a type of transform coding for lossy compression, was proposed by Nasir Ahmed in 1972, developed by Ahmed with T. Natarajan and K. R. Rao in 1973, publishing their results in 1974; this led to the development of the modified discrete cosine transform, proposed by J. P. Princen, A. W. Johnson and A. B. Bradley in 1987, following earlier work by Princen and Bradley in 1986; the MP3 audio coding standard introduced in 1994 used a hybrid coding algorithm, part MDCT and part FFT. AAC uses a purely MDCT algorithm, giving it higher compression efficiency than MP3. AAC was developed with the cooperation and contributions of companies including Bell Labs, Fraunhofer IIS, Dolby Laboratories, LG Electronics, NEC, NTT Docomo, Sony Corporation, ETRI, JVC Kenwood, Microsoft, NTT.

It was declared an international standard by the Moving Picture Experts Group in April 1997. It is specified both as Part 7 of the MPEG-2 standard, Subpart 4 in Part 3 of the MPEG-4 standard. In 1997, AAC was first introduced as MPEG-2 Part 7, formally known as ISO/IEC 13818-7:1997; this part of MPEG-2 was a new part, since MPEG-2 included MPEG-2 Part 3, formally known as ISO/IEC 13818-3: MPEG-2 BC. Therefore, MPEG-2 Part 7 is known as MPEG-2 NBC, because it is not compatible with the MPEG-1 audio formats. MPEG-2 Part 7 defined three profiles: Low-Complexity profile, Main profile and Scalable Sampling Rate profile. AAC-LC profile consists of a base format much like AT&T's Perceptual Audio Coding coding format, with the addition of temporal noise shaping, the Kaiser window, a nonuniform quantizer, a reworking of the bitstream format to handle up to 16 stereo channels, 16 mono channels, 16 low-frequency effect channels and 16 commentary channels in one bitstream; the Main profile adds a set of recursive predictors that are calculated on each tap of the filterbank.

The SSR uses a 4-band PQMF filterbank, with four shorter filterbanks following, in order to allow for scalable sampling rates. In 1999, MPEG-2 Part 7 was updated and included in the MPEG-4 family of standards and became known as MPEG-4 Part 3, MPEG-4 Audio or ISO/IEC 14496-3:1999; this update included several improvements. One of these improvements was the addition of Audio Object Types which are used to allow interoperability with a diverse range of other audio formats such as TwinVQ, CELP, HVXC, Text-To-Speech Interface and MPEG-4 Structured Audio. Another notable addition in this version of the AAC standard is Perceptual Noise Substitution. In that regard, the AAC profiles are combined with perceptual noise substitution and are defined in the MPEG-4 audio standard as Audio Object Types. MPEG-4 Audio Object Types are combined in four MPEG-4 Audio profiles: Main, Scalable and Low Rate Synthesis; the reference software for MPEG-4 Part 3 is specified in MPEG-4 Part 5 and the conformance bit-streams are specified in MPEG-4 Part 4.

MPEG-4 Audio remains backward-compatible with MPEG-2 Part 7. The MPEG-4 Audio Version 2 defined new audio object types: the low delay AAC object type, bit-sliced arithmetic coding object type, parametric audio coding using harmonic and individual line plus noise and error resilient versions of object types, it defined four new audio profiles: High Quality Audio Profile, Low Delay Audio Profile, Natural Audio Profile and Mobile Audio Internetworking Profile. The HE-AAC Profile and AAC Profile were first standardized in ISO/IEC 14496-3:2001/Amd 1:2003; the HE-AAC v2 Profile was first specified in ISO/IEC 14496-3:2005/Amd 2:2006. The Parametric Stereo audio object type used in HE-AAC v2 was first defined in ISO/IEC 14496-3:2001/Amd 2:2004; the current version of the AAC standard is defined in ISO/IEC 14496-3:2009. AAC+ v2 is standardized by ETSI (Eur

James John Fraser

Sir James John Fraser, 3rd Baronet of Leadclune was a Lieutenant-Colonel in the British Army. Fraser was descended from Alexander Fraser, second son of Hugh Fraser, 1st Lord Lovat, was the second son of Sir William 1st Baronet, F. R. S. by Elizabeth, daughter of James Farquharson, esq. merchant, of London. Fraser served with the 7th Hussars in Spain during the Peninsular War, was on the staff of the Duke of Wellington during the Waterloo Campaign, he died on 5 June 1834, at his seat, Uddens House, after a short illness, aged 45, leaving a widow and three sons. There are memorial inscriptions to Fraser in All Saint's Church, Langton Long Blandford, at Wimborne Minster, Dorset and on the family memorial tablet in Boleskine Old Churchyard, Invernesshire; the eldest son, Sir William Fraser, 4th Baronet was born in 1826, graduated B. A. and M. A. at Christ church, in 1847 was appointed an officer in the 1st Life Guards, subsequently captain. In 1852 and 1857 he was the Member of Parliament for Barnstaple.

His brother, Charles Craufurd, was a Lieutenant-Colonel 11th Hussars, V. C. 1861, was at one time aide-de-camp to the lord-lieutenant of Ireland, distinguished himself in India. The youngest brother, James Keith, was in 1860 a captain first life guards

Glims Farmstead Museum

Glims Farmstead Museum is a museum located in Espoo, Finland and a branch of the Espoo City Museum. Glims tells about farming culture and rural life in the past centuries; the Glims farm was still a working farm in the beginning of the 20th century and it has been a museum since 1958. The museum area is located next to Jorvi Hospital; the Glims farm has a large yard accompanied by 11 original buildings. Most of the buildings are from the 19th century but the oldest ones were built in the 18th century; the Glims farm is part of the Karvasmäki village, inhabited since the stone age. The name Glims appeared in formal documents for the first time in the 16th century; the farm was owned by the Lönnberg family between 1800-1950. The farm was sold to the city of Espoo in 1950. After that the farm buildings were used as rental lodgings; the official website of Glims Farmstead Museum