  Advances in development of quantum computing processors brought ample
opportunities to test the performance of various quantum algorithms with
practical implementations. In this paper we report on implementations of
quantum compression algorithm that can efficiently compress unknown quantum
information. We restricted ourselves to compression of three pure qubits into
two qubits, as the complexity of even such a simple implementation is barely
within the reach of today's quantum processors. We implemented the algorithm on
IBM quantum processors with two different topological layouts - a fully
connected triangle processor and a partially connected line processor. It turns
out that the incomplete connectivity of the line processor affects the
performance only minimally. On the other hand, it turns out that the
transpilation, i.e. compilation of the circuit into gates physically available
to the quantum processor, crucially influences the result. We also have seen
that the compression followed by immediate decompression is, even for such a
simple case, on the edge or even beyond the capabilities of currently available
quantum processors.
