Hi All,

I am wanting to use the QT native call:

void GetMediaSampleDescription(Media theMedia, long index, SampleDescriptionHandle descH);

Media is basically an int (it's actually a the native pointer for a QTJ object, which we obtain be using the static QTObject.ID(QTObject object))

SampleDescritionHandle is a SampleDescriptionPtr *

SampleDescriptionPtr is a SampleDescription *

and Sample Description is:

struct SampleDescription { long descSize; long dataFormat; long resvd1; short resvd2; short dataRefIndex; }

So, essentially our native call boils down to:

void GetMediaSampleDescription(int mediaObjectId, long index, SampleDescription ** desc);

The descSize field tells us the actual size of the structure as this depends upon the media that it is describing. So, at the time this function is called, we have no idea of the size of the structure (or a narrow range of different sized structures based on the media type if we know that).

My question is: How does one map this function in Java with JNA?

Paul.