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ScreenCam (formerly ''Lotus/IBM ScreenCam'') is a Screencast tool for Microsoft Windows that is used to author software demonstrations, software simulations, branched scenarios, and tutorials in .swf (also known as Adobe Flash) format. ScreenCam was primarily targeted at users who need to create video-oriented instructional materials who were not multimedia authors or video capture technicians. It was very easy to use, having a 'VCR-like' interface and requiring no knowledge of digital video editing, or the concept of 'frames' of a movie, because it used a different paradigm for creating the screen movies. It can also be used for creation of screencasts and conversion of Microsoft PowerPoint presentations to the Adobe Flash format. ==History== ScreenCam was originally produced in the early 90s and received good reviews compared to other technologies of the time. It was considered one of the earliest screencasting products commercially available in the 1990s, and was popular for streaming and broadcasting of screen demos and tutorials at that time. ScreenCam utilized the concept of intercepting and storing Video Procedure Calls (VPCs) in Windows 95 using a proprietary capture extension which invasively intercepted VPCs as the operating system generated them. These VPCs were stored in a proprietary format and a player which generated a 'movie' of what was recorded by sending these same VPC calls to the OS created a very lifelike playback of the recorded screen. It was considered very clever at the time, and put the concept of screen recording and software simulation on the map in the computing world. Although some other commercial software did similar things, especially on Unix Workstation OS side of the world, the widespread adoption of Windows 95 went a long ways to establishing ScreenCam's dominance in this area. Eventually, ScreenCam was acquired by IBM when IBM purchased Lotus Corporation, and ScreenCam's programmers kept doing minor updates to the product line. This technique worked well enough that a 2003 PC Magazine review gave ScreenCam good marks even after IBM/Lotus stopped supporting newer OSes. However, problems began to surface in trying to bring the technology forward. As Microsoft Windows matured and spread, the "VPC capture" design started to show its age, and programs that invasively intercepted procedure calls became difficult to support. The technique was also problematic when a ScreenCam movie was moved to a computer which was missing fonts and icons that existed on the OS which was recorded. Since the playback OS was missing these fonts and icons, the playback OS would substitute fonts and icons, making the playback messy and inaccurate. ScreenCam files, which were really a storage mechanism for VPCs, was difficult to edit, and featured limited interactivity and web browser compatibility. IBM did move to support Windows NT 4.0, but eventually IBM decided to not pursue the screen capture software business any further, and the brand name "ScreenCam" was acquired by SmartGuyz Incorporated, a private software developer. SmartGuyz subsequently released a completely new ScreenCam program, based not on VPC capture, but on periodic capture of the screen and cursor position, an integrated editor, and export to known standard video and graphics formats. This ameliorated the problems caused by capturing and playing back VPCs, and allowed ScreenCam an upgrade path to newer OSes and the Internet. 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「Screencam」の詳細全文を読む スポンサード リンク
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