nicht angemeldet
Hallo klawischnigg,
Jetzt hast Du mich neugierig gemacht, also hab ich mal ein bisschen gegoogelt
Ich zitiere mal Wikipedia http://en.wikipedia.org/wiki/Gif
<zitat>
The original version of GIF was 87a. In 1989, CompuServe devised an enhanced version, called 89a [1] (http://www.w3.org/Graphics/GIF/spec-gif89a.txt), that added support for multiple images in a stream and storage of application-specific metadata. The two versions can be distinguished by looking at the first six bytes of the file, which, when interpreted as ASCII, read "GIF87a" and "GIF89a", respectively.
When the World Wide Web gained popularity, GIF became one of the two image formats commonly used on Web sites, the other being JPEG. Most Internet browsers at this time did not support any other image formats, not even uncompressed Windows bitmap files, to discourage web designers from using files larger than necessary.
The GIF89a feature of storing multiple images in one file, accompanied by control data, is used extensively on the web to produce simple animations.
</zitat>
Das heisst, 89a konnte erst animiert werden
David Simmons erklaert uns dazu http://www.davidsimmons.com/tips/081097/
<zitat>
Animated GIFs are implemented using the GIF89A specification for image storage. This specification, formed in 1989, provides the option of including multiple image frames in GIFs. When displayed, these image frames are shown in sequence with a specified time delay between each. After the last image is displayed, animation stops.
Netscape Communications, Inc. introduced an application extention to the GIF89A specification which designated "looping" to allow a GIF89A gif animation to return to the first frame when the last frame is displayed, providing continuous animation. The extention consists of the text "NETSCAPE2.0", probably named after the version of Netscape's browser which first implemented this extention. All animated GIFs you encounter on the web which loop forever contain this extention.
</zitat>
Also bedeutet Gif89a, das Bild _koennte_ animiert sein, Gif89a und NETSCAPE2.0 zusammen, ein Gif _ist_ animiert und kann loopen. Gif87a ist statisch. Noch ein paar animierte Gifs aus Prä-Netscape-Zeiten zu zerlegen, ueberlasse ich dem OP
Gruß,
Dieter