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Movies

A movie is a set of images, which are displayed sequentially. This video track can have an accompanying audio track, but in this context I will not be dealing with the latter.

Some of the movie file formats found on the Web are:

MPEG (Moving Picture Expert Group):
There are several types of MPEG: MPEG-1, MPEG-2, and MPEG-4. It seems to me, that the MPEG most often found on the Web is MPEG-1, and usually with only a video track. MPEG seems to be by far the most popular movie format on the Web, and therefore it is one of the formats I offer the movies of this project in.
MPEG uses 3 different compression techniques at once, with one of them being similar to JPEG. The compression is lossy and efficient.
For more information about MPEG, see the MPEG FAQ, the Moving Picture Expert Group Information Page, and the the first two sections of the article by Patel, Smith, & Rowe (1993).
For the record: MPEG is also known as ISO/IEC JTC1 SC29 WG11 ;-)
QuickTime:
QuickTime seems to be an Apple product; they host a Web site about it. However, viewers and encoders for other platforms are available. QuickTime can store among other things movies, using different compression schemes. For this project, I have chosen ``Animation'', which is an RLE scheme. This compression I presume is loss free. For this reason, I also offer my movies in that format.
For more information about QuickTime, see the QuickTime FAQ.
Animated GIF:
The GIF89 standard supports multiple images in the same file, and an animation of these. Netscape has a built-in viewer not only for GIFs but also for animated GIFs, so therefore animated GIF has a big advantage. Besides, Netscape will show the movie while it is being loaded. For the these reasons, I have also made my movies of this project as animated GIF. On the downside, it is not possible to single step the frames, play the movie again, etc.


next up previous contents
Next: 3D Scenes Up: Multimedia content types Previous: Still images

Web Exhibition: Null Geodesics Around a Kerr Black Hole

Bo Milvang-Jensen (milvang@astro.ku.dk)
Mon Jun 17 11:54:08 MDT 1996