Windows Media Audio (WMA) is a series of audio codecs and their corresponding audio coding formats developed by Microsoft. It is a proprietary technology that forms part of the Windows Media framework. WMA consists of four distinct codecs. The original WMA codec, known simply as WMA, was conceived as a competitor to the popular MP3 and RealAudio codecs. WMA Pro, a newer and more advanced codec, supports multichannel and high resolution audio. A lossless codec, WMA Lossless, compresses audio data without loss of audio fidelity. WMA Voice, targeted at voice content, applies compression using a range of low bit rates. Microsoft has also developed a digital container format called Advanced Systems Format to store audio encoded by WMA.
Dirac is an open and royalty-free video compression format, specification and system developed by BBC Research & Development. Schrödinger and dirac-research are open and royalty-free software implementations of Dirac. Dirac format aims to provide high-quality video compression for Ultra HDTV and beyond, and as such competes with existing formats such as H.264 and VC-1.
Windows Media Video (WMV) is a series of video codecs and their corresponding video coding formats developed by Microsoft. It is part of the Windows Media framework. WMV consists of three distinct codecs: The original video compression technology known as WMV, was originally designed for Internet streaming applications, as a competitor to RealVideo. The other compression technologies, WMV Screen and WMV Image, cater for specialized content. After standardization by the Society of Motion Picture and Television Engineers (SMPTE), WMV version 9 was adapted for physical-delivery formats such as HD DVD and Blu-ray Disc and became known as VC-1. Microsoft also developed a digital container format called Advanced Systems Format to store video encoded by Windows Media Video.
Smart Bitrate Control, commonly referred to as SBC, was a technique for achieving greatly improved video compression efficiency using the DivX 3.11 Alpha video codec or Microsoft's proprietary MPEG4v2 video codec and the Nandub video encoder. SBC relied on two main technologies to achieve this improved efficiency: Multipass encoding and Variable Keyframe Intervals (VKI). SBC ceased to be commonly used after XviD and DivX development progressed to a point where they incorporated the same features that SBC pioneered and could offer even more efficient video compression without the need for a specialized application. Files created by SBC are compatible with DivX 3.11 Alpha and can be decoded by most codecs that support ISO MPEG4 video.
Windows Media High Definition Video is the marketing name for high definition videos encoded using Microsoft Windows Media Video 9 codecs. These low-complexity codecs make it possible to watch high definition movies in 1280×720 (720p) or 1920×1080 (1080p) resolutions on many modern personal computers running Microsoft Windows XP or Windows Vista, although the hardware requirements are steep. Microsoft's Xbox 360 and Sony's PlayStation 3 video game consoles can also play WMV HD.
A container or wrapper format is a metafile format whose specification describes how different elements of data and metadata coexist in a computer file.
Indeo Video is a family of audio and video formats and codecs first released in 1992, and designed for real-time video playback on desktop CPUs. While its original version was related to Intel's DVI video stream format, a hardware-only codec for the compression of television-quality video onto compact discs, Indeo was distinguished by being one of the first codecs allowing full-speed video playback without using hardware acceleration. Also unlike Cinepak and TrueMotion S, the compression used the same Y'CbCr 4:2:0 colorspace as the ITU's H.261 and ISO's MPEG-1. Indeo use was free of charge to allow for broadest usage.
Avid DNxHD is a lossy high-definition video post-production codec developed by Avid for multi-generation compositing with reduced storage and bandwidth requirements. It is an implementation of SMPTE VC-3 standard.
Microsoft Video 1 or MS-CRAM is an early lossy video compression and decompression algorithm (codec) that was released with version 1.0 of Microsoft's Video for Windows in November 1992. It is based on MotiVE, a vector quantization codec which Microsoft licensed from Media Vision. In 1993, Media Vision marketed the Pro Movie Spectrum, an ISA board that captured video in both raw and MSV1 formats.
The following tables compare general and technical information for a variety of audio coding formats. For listening tests comparing the perceived audio quality of audio formats and codecs, see the article Codec listening test.
The first attempt at producing pre-recorded HDTV media was a scarce Japanese analog MUSE-encoded laser disc which is no longer produced.
Windows Imaging Component (WIC) is a Component Object Model based imaging codec framework introduced in Windows Vista for working with and processing digital images and image metadata. It allows applications supporting the framework to automatically get support of installed codecs for graphics file formats.
Microsoft Expression Encoder is a transcoding and non-linear video editing software application for Microsoft Windows. It can create video streams for distribution via Microsoft Silverlight. This utility is created to record the screen for various purposes like YouTube, Twitch, Sharing etc.
H.264 and VC-1 are popular video compression standards gaining use in the industry as of 2007.
Moonlight is a free and open source implementation of the now deprecated Microsoft Silverlight application framework for Linux and other Unix-based operating systems, developed and then abandoned by the Mono Project. Like Silverlight, Moonlight was a web application framework which provided capabilities similar to those of Adobe Flash, integrating multimedia, graphics, animations and interactivity into a single runtime environment.
PureVideo is Nvidia's hardware SIP core that performs video decoding. PureVideo is integrated into some of the Nvidia GPUs, and it supports hardware decoding of multiple video codec standards: MPEG-2, VC-1, H.264, and HEVC. PureVideo occupies a considerable amount of a GPU's die area and should not be confused with Nvidia NVENC. In addition to video decoding on chip, PureVideo offers features such as edge enhancement, noise reduction, deinterlacing, dynamic contrast enhancement and color enhancement.
Video Acceleration API is a royalty-free API as well as its implementation as free and open-source library (libVA) distributed under the MIT License.
Siren is a family of patented, transform-based, wideband audio coding formats and their audio codec implementations developed and licensed by PictureTel Corporation. There are three Siren codecs: Siren 7, Siren 14 and Siren 22.
