oggdec -o - test.ogg | oggenc -q 9 -o testSmall.ogg -
would be nice is this was added to the examples in the man page since i am sure many want it and not quickly obviously scanning the man page unless you read the fine print. the unobvious part is how to send to stdout from oggdec, though it is mentioned in one of the first paragraphs
oggdec -o - test.ogg | oggenc -q 9 -o testSmall.ogg -
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