DirectShow

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" (see digital rights management). Microsoft's Becky Weiss confirmed in 2006 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. The direct predecessor of DirectShow, ActiveMovie (codenamed Quartz), was designed to provide MPEG-1 support for Windows. It was also intended as a future replacement for media processing frameworks like Video for Windows and the Media Control Interface, which had never been fully ported to a 32-bit environment and did not utilize COM. The development team used a pre-existing modular digital-media-processor project codenamed "Clockwork" as a basis for DirectShow. Clockwork had previously been used in the Microsoft Interactive Television project.