Video for Windows

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Screenshot of Media Player, one of the components of Video for Windows

Video for Windows (VfW), also referred to as Video Compression Manager (VCM), was a multimedia framework developed by Microsoft that allowed Microsoft Windows users to play and encode digital video.

Overview[edit]

Video for Windows was first introduced in November 1992. Video for Windows was developed as a reaction to Apple Computer's QuickTime technology, which added digital video to the Macintosh platform. Costing around $200,[1] the software included editing and encoding programs for use with video input boards. A runtime version for viewing videos only was also made available. Originally released as a free add-on to Windows 3.1 and Windows 3.11, it then became an integral component of Windows 95 and later. Like QuickTime there were three components in Video for Windows. The technology introduced a file format designed to store digital video, Audio Video Interleave (AVI). The technology provided an application programming interface that allowed software developers working on the Windows platform to add the ability to play or manipulate digital video to their own applications. Lastly, it included a suite of software for playing and manipulating digital video:

The original version had a number of limitations including a maximum resolution of 320 pixels by 240 pixels and a maximum framerate of 30 frames per second.

The Video for Windows technology was mostly replaced by the July 1996 release of its COM-based successor - ActiveMovie (later known as DirectShow) - first released as a beta version along with the second beta of Internet Explorer 3.0.[2] ActiveMovie was also released as a free download, either standalone or bundled with a version of Internet Explorer. One component that was not replaced with ActiveMovie was video capture, which still required an install of Video for Windows until the release of WDM capture drivers, which only started to become popular in 2000.

In 1995, Video for Windows became an issue in a lawsuit Apple filed against Microsoft, Intel, and the San Francisco Canyon Company, regarding the alleged theft of several thousand lines of QuickTime source code to improve the performance of Video for Windows.[3][4][5][6] This lawsuit was ultimately settled in 1997, when Apple agreed to make Internet Explorer the default browser over Netscape, and Microsoft agreed to continue developing Office and other software for the Mac for the next 5 years, and purchase $150 million of non-voting Apple stock.[7][8]

In March 1997, Microsoft announced that ActiveMovie would become part of the DirectX 5 suite of technologies,[9] and around July started referring to it as DirectShow.[10]

Version history[edit]

Release Date Version Notes
November 1992 Video for Windows 1.0 First public release. Including Microsoft RLE and Video1 codecs.
  Video for Windows 1.1 Added Cinepak codec
  Video for Windows 1.1a  
  Video for Windows 1.1b  
  Video for Windows 1.1c  
  Video for Windows 1.1d Included Indeo 3.2 (Allegedly included source code from Apple's QuickTime for Windows)
March 1995 Video for Windows 1.1e Last version for Windows 3.1x
August 1995 Video for Windows 95 Bundled with Windows 95
July 1996 Video for Windows NT 32-bit version bundled with Windows NT 4.0
July 1996 ActiveMovie 1.0 The successor to Video for Windows. Added support for MPEG-1 and QuickTime file formats
March 1997 DirectShow 1.0 The successor to Active Movie.

Example[edit]

This sample source code shows skeleton of video codec in VfW:

#include <vfw.h>
…
LRESULT WINAPI DriverProc(
	DWORD dwDriverId, 
	HDRVR hdrvr,
	UINT msg,
	LONG lParam1, 
	LONG lParam2)
{
	switch(msg)
	{case ICM_COMPRESS:
			// compress frame
			return Compress((ICCOMPRESS*)lParam1, (DWORD)lParam2);case ICM_DECOMPRESS:
			// decompress frame
			return Decompress((ICDECOMPRESS*)lParam1, (DWORD)lParam2);}
}

See also[edit]

References[edit]

  1. ^ Future Publishing (May 1993). PC Plus. p. 61. 
  2. ^ Microsoft (July 16, 1996). "Microsoft Delivers ActiveMovie for Microsoft Internet Explorer 3.0". Microsoft PressPass. Retrieved 2006-12-31. 
  3. ^ Markoff, John. "Intel and Microsoft Added to Apple Lawsuit", New York Times, February 10, 1995
  4. ^ Duncan, Geoff. "Apple Sues Intel, Microsoft - Again', TidBITS, February 13, 1995
  5. ^ Mace, Michael. "An Open Letter to the Computing Community", archived from apple.com, February 9, 1995
  6. ^ Mace, Michael. "Second open letter from Apple", archived from apple.com
  7. ^ Kawamoto, Dawn; Heskett, Ben; Ricciuti, Mike. "MS to invest $150 million in Apple", CNET News, August 6, 1997
  8. ^ "Preferred Stock Purchase Agreement", FindLaw, August 5, 1997
  9. ^ Microsoft (March 31, 1997). "Microsoft Unveils First Unified Multimedia API Strategy". Microsoft PressPass. Retrieved 2006-12-31. 
  10. ^ Microsoft (July 21, 1997). "Microsoft and Progressive Networks Collaborate on Streaming Media". Microsoft PressPass. Retrieved 2006-12-31.