How to slow down/speed up video using JMF?

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nick.degraeve@pandora.be - 05 Feb 2006 06:55 GMT

I've been asked to write an app were the user can slow down or speed up
video and even reverse it. Only video is required, no audio.
I've done a test with a Quicktime movie and using setRate(). It didn't
work, though, as the rate always stays at 1.0 no matter what I set.

Do I need to use a specific codec for it to work? It there something
about setRate() that I overlooked?

Nick.

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Roedy Green - 05 Feb 2006 08:00 GMT

>Do I need to use a specific codec for it to work? It there something
>about setRate() that I overlooked?

There are two different concepts.

1. how often do I display a frame? This measures the smoothness
quality.

2. how far apart in time to I display two frames that were 1 second
apart in real time? this measure the slow/fast motionness.

Read the docs carefully to see which setRate controls and if there is
one for the other concept.

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http://mindprod.com Java custom programming, consulting and coaching.

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Nick de Graeve - 05 Feb 2006 18:00 GMT

>> Do I need to use a specific codec for it to work? It there something
>> about setRate() that I overlooked?
[quoted text clipped - 9 lines]
> Read the docs carefully to see which setRate controls and if there is
> one for the other concept.

The 2nd one is wat I need and setRate() seems the way to go. But I'm
starting to fear that I need to create a Controller myself.
Unfortunately the reference implementation on the Sun site
(http://java.sun.com/products/java-media/jmf/2.1.1/guide/JMFApp-Controller.html)
is missing 2 important classes.

NdG.

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History of and technical information on movie sound systems.
De geschiedenis van en technische informatie over geluidssystemen voor
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How to slow down/speed up video using JMF?

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