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26-591: USAC may refer to: Unified Speech and Audio Coding , an audio compression scheme United States Army Cadet Corps , a non-profit youth education organization United States Auto Club , a sanctioning body for auto racing in the United States Universal Service Administrative Company , a not-for-profit corporation located in Washington, DC Universidad de San Carlos de Guatemala ,

52-432: A multimedia file is partitioned into one or more segments and delivered to a client using HTTP . A media presentation description (MPD) describes segment information (timing, URL , media characteristics like video resolution and bit rates ), and can be organized in different ways such as SegmentList, SegmentTemplate, SegmentBase and SegmentTimeline, depending on the use case. Segments can contain any media data, however

78-758: A University in Guatemala City, Guatemala USA Cycling , or USAC, a governing body for bicycle racing in the United States USA Cricket , a governing body for the sport of cricket in the United States USA Climbing , a governing body for the sport of competition climbing in the United States Utah State Agricultural College , now known as Utah State University, a school in Logan, Utah, USA Topics referred to by

104-812: A consistent performance at low data rates while being able to decode all existing AAC-LC , HE-AAC and HE-AACv2 content. Fraunhofer has defined the xHE-AAC codec as the combination of the Extended High Efficiency AAC profile and appropriate parts of the MPEG-D DRC Loudness Control Profile or Dynamic Range Control Profile. xHE-AAC extends the operating range of the codec from 12 to 300 kbit/s for stereo signals and allows seamless switching between bitrates over this range for adaptive bitrate delivery (using standards such as MPEG-DASH or HLS for example). xHE-AAC also includes MPEG-D DRC mandatory loudness control to playback content at

130-415: A consistent volume and offers new dynamic range control profiles for listening in noisy situations. While xHE-AAC decoders will be able to decode the bit streams created for the previous AAC family profiles, xHE-AAC encoders are typically intended for encoding of MPEG-D USAC audio object type (AOT 42) with MPEG-D DRC loudness metadata, though some may support encoding legacy AAC object types. xHE-AAC

156-554: A signal-responsive manner. It is being developed with the aim of a single, unified coder with performance that equals or surpasses that of dedicated speech coders and dedicated music coders over a broad range of bitrates. Enhanced variations of the MPEG-4 Spectral Band Replication (SBR) and MPEG-D MPEG Surround parametric coding tools are integrated into the USAC codec. The MPEG-D USAC standard (ISO/IEC 23003-3) defines

182-452: A specification into a real business. It consists of major streaming and media companies, including Microsoft, Netflix, Google, Ericsson, Samsung, Adobe, etc. and creates guidelines on the usage of DASH for different use cases in practice. MPEG-DASH is integrated in other standards, e.g. MPEG-DASH is supported in HbbTV (as of Version 1.5). DASH is an adaptive bitrate streaming technology where

208-529: Is a mandatory audio codec in the Digital Radio Mondiale standard and is a trademark of Fraunhofer. In April 2016, Via Licensing announced the launch of a xHE-AAC patent pool licensing program for 2016. In 2018, xHE-AAC was included in Via Licensing's AAC patent pool at no additional cost. In January 2021, Fraunhofer announced a test service and trademark program for xHE-AAC and announced that

234-473: Is based on Adaptive HTTP streaming (AHS) in 3GPP Release 9 and on HTTP Adaptive Streaming (HAS) in Open IPTV Forum Release 2. As part of their collaboration with MPEG, 3GPP Release 10 has adopted DASH (with specific codecs and operating modes) for use over wireless networks. The DASH Industry Forum ( DASH-IF ) further promotes and catalyzes the adoption of MPEG-DASH and helps transition it from

260-400: Is different from Wikidata All article disambiguation pages All disambiguation pages Unified Speech and Audio Coding It uses time-domain linear prediction and residual coding tools ( ACELP -like techniques) for speech signal segments and transform coding tools ( MDCT -based techniques) for music signal segments and it is able to switch between the tool sets dynamically in

286-524: Is supported by the Bento4 DASH/HLS packager. In January 2022, MainConcept established a web encoding service to test xHE-AAC. In October 2022, xHE-AAC decoding was added to Windows 11 and Xbox devices. xHE-AAC is supported in Android since Android Pie and in iOS since iOS 13 . It has been announced that it will be added to watchOS 7 and has been licensed to Microsoft . Playing xHE-AAC audio files

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312-544: Is supported in foobar2000 with the use of an add-on AAC decoder. In October 2022, Windows 11 added support for xHE-AAC in the 22H2 update. MPEG-DASH Dynamic Adaptive Streaming over HTTP ( DASH ), also known as MPEG-DASH , is an adaptive bitrate streaming technique that enables high quality streaming of media content over the Internet delivered from conventional HTTP web servers. Similar to Apple's HTTP Live Streaming (HLS) solution, MPEG-DASH works by breaking

338-608: Is the first adaptive bit-rate HTTP-based streaming solution that is an international standard. MPEG-DASH should not be confused with a transport protocol — the transport protocol that MPEG-DASH uses depends on which version of HTTP is used: TCP over HTTP and HTTP/2 , or UDP over HTTP/3 . MPEG-DASH uses existing HTTP web server infrastructure that is used for delivery of essentially all World Wide Web content. It allows devices like Internet-connected televisions, TV set-top boxes, desktop computers, smartphones, tablets, etc. to receive multimedia content (video, TV, radio, etc.) delivered via

364-518: The Extended High Efficiency AAC profile, which contains all of the tools of the HE-AAC v2 profile plus the mono/stereo capabilities of the Baseline USAC profile. As a result, a decoder built according to the Extended High Efficiency AAC profile is able to also decode the bit streams created for the previous AAC family profiles. The Extended High Efficiency AAC profile was designed for applications relying on

390-613: The HTML5 Media Source Extensions (MSE). There are also JavaScript implementations such as the bitdash player which support DRM for MPEG-DASH using the HTML5 Encrypted Media Extensions . In combination with WebGL, the HTML5-based adaptive bitrate streaming of MPEG-DASH enables also the efficient streaming of 360° video for live and on-demand use cases. Note that no specific support is required from

416-508: The Internet, coping with variable Internet receiving conditions. Standardizing an adaptive streaming solution is meant to provide confidence to the market that the solution can be adopted for universal deployment, compared to similar but more proprietary solutions like Smooth Streaming by Microsoft, or HDS by Adobe. Unlike HDS, or Smooth Streaming, DASH is codec-agnostic , which means it can use content encoded with any coding format , such as H.265 , H.264 , VP9 , etc. MPEG-DASH technology

442-675: The MPEG Dynamic Adaptive Streaming over HTTP standard. MPEG-DASH is available natively on Android through the ExoPlayer, on Samsung Smart TVs 2012+, LG Smart TV 2012+, Sony TV 2012+, Philips NetTV 4.1+, Panasonic Viera 2013+ and Chromecast. YouTube as well as Netflix already support MPEG-DASH, and different MPEG-DASH players are available. While MPEG-DASH isn't directly supported in HTML5, there are JavaScript implementations of MPEG-DASH which allow using MPEG-DASH in web browsers using

468-434: The adaptive bitrate streaming (ABR) logic. DASH is also agnostic to the underlying application layer protocol. Thus, DASH can be used with any protocol, e.g., DASH over CCN . On July 27, 2015, MPEG LA announced a call for MPEG-DASH-related patents in order to create a single patent pool for this technology. MPEG LA announced its MPEG-DASH patent portfolio licence. MPEG-LA claims that the included patents are essential to

494-441: The codec is being used by Netflix. Netflix reported that users switched from speakers to headphones 16% less often (due to poor sound quality or inadequate volume) on high dynamic range content when using xHE-AAC instead of HE-AAC. Netflix also explained that xHE-AAC allowed them to begin streaming with adaptive audio bitrates to Android devices. Fraunhofer also announced xHE-AAC licenses to MainConcept, Poikosoft, and LG. xHE-AAC

520-513: The content into a sequence of small segments, which are served over HTTP . An early HTTP web server based streaming system called SProxy was developed and deployed in the Hewlett Packard Laboratories in 2006. It showed how to use HTTP range requests to break the content into small segments. SProxy shows the effectiveness of segment based streaming, gaining best Internet penetration due to the wide deployment of firewalls, and reducing

546-589: The content is being played back by an MPEG-DASH client, the client uses a bit rate adaptation (ABR) algorithm to automatically select the segment with the highest bit rate possible that can be downloaded in time for playback without causing stalls or re-buffering events in the playback. The current MPEG-DASH reference client dash.js offers both buffer-based (BOLA ) and hybrid (DYNAMIC ) bit rate adaptation algorithms. Thus, an MPEG-DASH client can seamlessly adapt to changing network conditions and provide high quality playback with few stalls or re-buffering events. MPEG-DASH

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572-405: The same term [REDACTED] This disambiguation page lists articles associated with the title USAC . If an internal link led you here, you may wish to change the link to point directly to the intended article. Retrieved from " https://en.wikipedia.org/w/index.php?title=USAC&oldid=1052721551 " Category : Disambiguation pages Hidden categories: Short description

598-693: The server for DASH content, with the exception of Live Streaming. Windows 10 used to have native support for DASH streaming in EdgeHTML , a proprietary browser engine that was used in Microsoft Edge (now referred to as Edge Legacy) before the transition to the Chromium-based Blink browser engine. Edge Legacy was included in Windows 10 up till version 2004. It was replaced by Edge Chromium in version 20H2. DASH support on other browsers & operating systems

624-558: The specification provides specific guidance and formats for use with two types of containers: ISO base media file format (e.g. MP4 file format) or MPEG-2 Transport Stream . DASH is audio/video codec agnostic. One or more representations (i.e., versions at different resolutions or bit rates) of multimedia files are typically available, and selection can be made based on network conditions, device capabilities and user preferences, enabling adaptive bitrate streaming and QoE (Quality of Experience) fairness . DASH standard does not specify

650-471: The unnecessary traffic transmission if a user chooses to terminate the streaming session earlier before reaching the end. Each segment contains a short interval of playback time of content that is potentially many hours in duration, such as a movie or the live broadcast of a sport event. The content is made available at a variety of different bit rates, i.e., alternative segments encoded at different bit rates covering aligned short intervals of playback time. While

676-590: Was developed under MPEG . Work on DASH started in 2010; it became a Draft International Standard in January 2011, and an International Standard in November 2011. The MPEG-DASH standard was published in April, 2012 but has been revised in 2019 and then once more in 2022 as [1] . DASH is a technology related to Adobe Systems HTTP Dynamic Streaming , Apple Inc. HTTP Live Streaming (HLS) and Microsoft Smooth Streaming . DASH

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