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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: 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