Opus (audio format)

Opus is a lossy audio coding format developed by Xiph and standardized by the IETF, designed to efficiently code speech and general audio in a single format, while remaining low-latency enough for real-time interactive communication and low-complexity enough for low end ARM3 processors. Opus replaces both Vorbis and Speex, and several blind listening tests have ranked it higher quality than any other standard audio format at any given bitrate, including MP3, AAC, and HE-AAC.

Opus combines the speech-oriented linear predictive coding SILK algorithm, and the lower-latency, MDCT-based CELT algorithm, switching between or combining them as needed for maximum efficiency. Bitrate, audio bandwidth, complexity, and algorithm can all be adjusted seamlessly in each frame. Opus has the low algorithmic delay (26.5 ms by default) necessary for use as part of a real-time communication link, permitting natural conversation, networked music performances, and live lip sync; by trading-off quality or size the delay can be reduced down to 5 ms. Its delay is exceptionally low compared to competing codecs, which require well over 100 ms, yet Opus performs very competitively with these formats in terms of quality per bitrate.

Opus

Opus may refer to:

Books and magazines

Theatre

Computing

Organisations

Transport

Opus (comic strip)

Opus was a Sunday strip drawn by Berkeley Breathed for a period of five years, 2003 to 2008. It was Breathed's fourth comic strip, following The Academia Waltz, Bloom County and Outland.

Set in Bloom County, the strip documented the adventures of Breathed's popular character Opus the Penguin, parodying both pop culture and politics along the way. It was launched with much fanfare on November 23, 2003, and was syndicated by Washington Post Writers Group. In early October 2008 the author declared he was terminating the strip because of his expectation that the United States is going to face tough times and his desire to depart from his most famous character "on a lighter note".

Characters

Opus

Opus is the title character and protagonist of the strip. Though he returned to Antarctica at the end of Outland, Opus traveled back home to Bloom County, only to find that time has changed everything and everyone he once held dear. His employment usually depended on the week's joke – since Opus began, he has so far been a political operative, a garbageman, and a newspaper ombudsman – but he was most often depicted as a syndicated cartoonist.

Opus (Schiller album)

Opus is the eighth studio album of the music project Schiller created by the German electronic musician Christopher Von Deylen. The album was announced on July 1, 2013 (2013-07-01) and was released on August 30, 2013 (2013-08-30). On this album Schiller has collaborated with Russian operatic soprano Anna Netrebko, French pianist Hélène Grimaud and German classical oboist Albrecht Mayer. Opus is the first release of the new label "Panorama" by Deutsche Grammophon. The album reached in its first week number 1 of the German albums chart and number 6 in Switzerland and number 10 in Austria. These are the highest entries of Schiller in Austria and Switzerland and the fourth number-1-album of Schiller in Germany. Schiller has received a Gold award in Germany in December 2013 for 100.000 sold albums of Opus. In 2014 there will be a reedition of the album: Opus - White Album.

Album

The album Opus combines electronic music with classical music such as Swan Lake. It's also inspired by and based on songs such as Gymnopédie no. 1 by Erik Satie, Edvard Grieg's Solveig's Song, Sergei Rachmaninoff's Rhapsody On A Theme Of Paganini op. 43 and Claude Debussy's Reverie. After Schiller already released some singles with classical influences such as "Ein schöner Tag" (2000) with German singer Isgaard and "Time for Dreams" (2008) with Chinese pianist Lang Lang, it's the first completely classical inspired album of Schiller. Originally it was planned as a purely instrumental album, but then it was supplemented with vocals during the developing process. For the creation of the album Christopher von Deylen travelled to the Coachella Valley in California, USA. The performances of Anna Netrebko were recorded in the Dvorák Hall of the Rudolfinum in Prague, Hélène Grimaud's performances were recorded at the Kaufman Astoria Studios in New York City, Diana Tishchenko's and Albrecht Mayer's performances were recorded at the b-sharp Studios in Berlin.

Codec (disambiguation)

Codec may mean:

Codec2

Codec2 is a low-bitrate speech audio codec (speech coding) that is patent free and open source. Codec2 compresses speech using sinusoidal coding, a method specialized for human speech. Bit rates of 3200 to 700 bit/s have been successfully created. Codec2 was designed to be used for amateur radio and other high compression voice applications.

Overview

The codec was developed by David Rowe (Amateur Radio Call-Sign VK5DGR), with support and cooperation of other researchers (e.g., Jean-Marc Valin from Speex). Codec2 uses sinusoidal coding to model speech. In sinusoidal coding, spoken audio is recreated by modelling speech as a sum of harmonically related sine waves with independent amplitudes called Line spectral pairs, or LSP. The fundamental frequency of the speaker's voice (pitch) and the amplitude (energy) of the harmonics is encoded, and with the LSP's are exchanged across a channel in a digital format. The LSP coefficients represent the Linear Predictive Coding (LPC) model in the frequency domain, and lend themselves to a robust and efficient quantisation of the LPC parameters.