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This article comprises the Read Me for Intel Indeo Video version 5. This software was released by Apple 13 May 1999 and is available for downloading from the Apple Software Updates Web site. Use the following URL to access the download directly:
DISCUSSION Intel(R) Indeo(R) Video 5 for QuickTime Release Notes Introduction Intel is pleased to introduce Indeo(R) video 5 for QuickTime. These release notes describe features of Indeo video for both Windows* and Macintosh* environments. Codec Availability Indeo video 5 is included with QuickTime 4. This file can be downloaded from the Apple website at http://www.apple.com/quicktime . Note : Indeo video 5 for QuickTime is NOT available for download from the Intel website. Performance enhancements Enhancements to Indeo video 5 for QuickTime include the following: Advanced features of Indeo video 5 The Indeo video 5 release includes most of the features in previous releases of Indeo video: Video access protection Many multimedia developers are concerned about the illegal distribution of their copyrighted material. The Indeo video 5 codec helps prevent misuse of video clips by using access keys (numeric passwords that can be inserted into a video clip during compression). Applications need the password to play video clips encoded with an access key. Key frame flexibility The Indeo video 5 codec offers control and flexibility over the use of key frames. The key frame interval is unrestricted, allowing a variety of values: Along with this flexibility in key frame intervals, Indeo video 5.1 allows for non-periodic key frames. This means that during editing, the encoding application can tell the Indeo video 5 codec to place a key frame at any location. Video producers can then specify access points anywhere within a video sequence, or better control video quality by placing key frames on scene-change boundaries. Application interactivity Indeo video 5 incorporates features that make it possible to include video in interactive multimedia applications and games, challenging the traditional notion of video as having a fixed size and rectangular shape. Transparency For years, the movie and television industries have used the technique of chroma-keying (sometimes called blue-screening) to place foreground objects over synthesized backgrounds. One example of chroma-keying is when TV meteorologists appear to be standing in front of a wall-sized map, when in fact, they are standing in front of a blue wall. Chroma-key circuitry electronically separates the foreground pixels representing the meteorologist from the blue background pixels, and overlays the meteorologist on an electronically-generated weather map. The Indeo video codec supports this type of transparency. During encoding, a compression application can send information to the codec describing a color or range of colors that represent a transparent background (such as the blue wall in the meteorologist example). Indeo video then analyzes each frame, separates the background pixels from the foreground, and makes the background pixels transparent, encoding only the foreground objects as compressed video. Indeo video 5's transparency encoding is flexible, allowing for arbitrarily-shaped multiple foreground objects. Foreground objects can also move from frame to frame, allowing you to create what might be called video sprites. Video sprites are transparent video objects that can be overlaid onto other video or bitmap backgrounds. During playback, foreground objects can be composited dynamically over different backgrounds. For example, the meteorologist can appear over different weather maps on PCs with sufficiently powerful Pentium processors. A foreground object can even appear over another video stream, as in the case of a tornado. Known limitations The following limitations are associated with the Indeo video 5 codec: |
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| Document Information | |
| Product Area: | Apple Software |
| Category: | QuickTime |
| Sub Category: | General Topics |
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