Currently the spec for java.awt.SplashScreen doesn't set any restrictions to the changes of the image that particular implementation might do - like flipping, scaling etc.
To assure that the image is shown properly somethign like the following should be added to the spec:

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When showing contents of graphical file the implementation should not make ant distortions like flipping, rotating or scaling the image. Nor should it add any additional decorating to it. The only case when downscaling is acceptable is when screen size is smaller than the image size - in this case splash screen window might be scaled down.
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