Unfortunately there's nothing exposed to BrightScript that gives this information. Even though the roVideoScreen has it, it doesn't make it available anywhere, as far as I've found. You'll need to rely on getting the metadata from someplace else, or trying to parse it from the file headers directly. In my custom roVideoPlayer implementations, I've opted to just show current playback time, if the overall length isn't provided, and show a full playback progress bar if it is.
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