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DirectShow (sometimes abbreviated as DS or DShow), codename Quartz, is a multimedia framework and API produced by Microsoft for software developers to perform various operations with media files or streams. It is the replacement for Microsoft's earlier Video for Windows technology. Based on the Microsoft Windows Component Object Model (COM) framework, DirectShow provides a common interface for media across various programming languages, and is an extensible, filter-based framework that can render or record media files on demand at the request of the user or developer. The DirectShow development tools and documentation were originally distributed as part of the DirectX SDK. Currently, they are distributed as part of the Windows SDK (formerly known as the Platform SDK). Microsoft plans to completely replace DirectShow gradually with Media Foundation in future Windows versions. One reason cited by Microsoft is to provide "much more robust support for content protection systems"〔http://social.msdn.microsoft.com/Forums/en-US/36661a0b-fefa-4719-8134-6956e505e6f7/is-the-new-media-foundation-a-replacement-of-direct-show?forum=mediafoundationdevelopment MSFT Becky Weiss〕 (see Digital rights management). Microsoft's MSFT Becky Weiss also confirms that "you'll notice that working with the Media Foundation requires you to work at a slightly lower level than working with DirectShow would have. And there are still DirectShow features that aren't (yet) in Media Foundation " As described in the Media Foundation article, Windows Vista and Windows 7 applications use Media Foundation instead of DirectShow for several media related tasks. == History == The direct predecessor of DirectShow, ActiveMovie (codenamed Quartz), was originally chartered to provide MPEG-1 file playback support for Windows. It was also intended as a future replacement for media processing frameworks like Video for Windows, which had never been designed to handle codecs that put video frames into a different order during the compression process, and the Media Control Interface, which had never been fully ported to a 32-bit environment and did not utilize COM.〔 The Quartz team started with an existing project called Clockwork. Clockwork was a modular media processing framework in which semi-independent components worked together to process digital media streams, and had previously been used in several projects, including the Microsoft Interactive Television (MITV) project and another project named Tiger. ActiveMovie was announced in March 1996, and released in May 1996, bundled with the beta version of Internet Explorer 3.0. In March 1997, Microsoft announced that ActiveMovie would become part of the DirectX 5 suite of technologies, and around July started referring to it as DirectShow, reflecting Microsoft's efforts at the time to consolidate technologies that worked directly with hardware under a common naming scheme. DirectShow became a standard component of all Windows operating systems starting with Windows 98; however it is available on Windows 95 by installing the latest available DirectX redistributable. In DirectX version 8.0, DirectShow became part of the mainline distribution of the DirectX SDK and was placed alongside other DirectX APIs. In October 2004, DirectShow was removed from the main DirectX distribution and relocated to the DirectX Extras download. In April 2005, DirectShow was removed entirely from DirectX and moved to the Windows Server 2003 SP1 version of the Microsoft Platform SDK.〔 The DirectX SDK was, however, still required to build some of the DirectShow samples. Since November 2007, DirectShow APIs are part of the Windows SDK. It includes several new enhancements, codecs and filter updates such as the Enhanced Video Renderer (EVR) and DXVA 2.0 (DirectX Video Acceleration). 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「DirectShow」の詳細全文を読む スポンサード リンク
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