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Animated GIFs Play Differently in Versions of PowerPoint
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An animated GIF has two
settings in its header, a "loop flag" and an "iteration setting". The
loop flag can have a value of 0 or 1, and a 1 indicates that the GIF
should be looped. The iteration setting indicates how many times the GIF
should be looped.
If loop=1 and iteration=0, the GIF will loop
endlessly. In most software, if loop=0 the GIF will play the number of
times indicated in the iteration setting. However, in PowerPoint 2003 a
loop value of 0 will cause the GIF to not animate at all,
regardless of a non-zero value in the iteration setting. In
PowerPoint 2002 a loop value of 0 will result in the GIF animating once,
regardless of the value in the iteration setting. In PowerPoint
2000, all animated GIFs loop continuously, regardless of the loop
and iteration settings. |
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If your animated GIF won't play in PowerPoint 2003 it
may be that the loop flag is set to zero. You can easily correct
this. Download and install the trial version of GIF
Construction
Set and open your GIF file in it. Double click on the first
"block", 1:HEADER. At the bottom of the dialog check the Loop box
and set the number of iterations to your choice (1-99). Save the
file with a new name. Insert it in your presentation and test it
in Slide Show mode. |
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The problem in PowerPoint 2003 was discovered as the
result of extensive testing. If you would like to see and
understand my test results, read on: |
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| I created 8
versions of the same animated GIF, varying the values of the loop flag
and the iteration setting. Then I played each of them in
PowerPoint 2002 and 2003 presentations and opened the GIF files in
Internet Explorer and Netscape. The results of my testing are
summarized in an Excel table and each of the test files are available
below for your own testing. See Test Results
(depending on your browser, you may need to right click and select "Save
Target As". |
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See what the files look
like in your browser: |
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| Loop = yes, Iterations = 0 (loops continuously in all applications) | |
| Loop = yes, Iterations = 1 | |
| Loop = yes, Iterations = 2 | |
| Loop = yes, Iterations = 5 | |
| Loop = no, Iterations = 0 | |
| Loop = no, Iterations = 1 | |
| Loop = no, Iterations = 2 | |
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Loop = no, Iterations = 5 |
All contents Copyrighted by Sonia Coleman 1998 - 2004