`unsigned_to_signed` does not update recording offset_to_uV

[ablot]

If I read a raw binary file that is saved in uint16 and correctly set the offset, calling unsigned_to_signed returns a recording with an invalid offset.

raw_rec = se.read_binary(
        data_file,
        sampling_frequency=30000.,
        dtype=np.uint16,
        num_channels=384,
        gain_to_uV=3.05176,
        offset_to_uV=-2048*3.05176,
    )
# we can use get_traces with return_in_uV, all is good

unsigned = si.unsigned_to_signed(raw_rec, bit_depth=12)
# now the trace in uV have an offset, exactly 2048*3.05176

Shouldn't the unsigned_to_signed subtract 2**bit_depth / 2 * gain from the offset? Or is it expected that the offset is unset when using this function?

[ablot]

Maybe related, for some reason using set_probe on an unsigned recording changes the value returned by get_traces, this does not happen if I call set_probe first and then convert to signed. I don't see anything in the probe mapping that would change the gain or offset.

recs = dict()
recs['raw'] = se.read_binary(
        ephys_path / f"np2-{prb_suffix}-ephys_{suffix}.raw",
        sampling_frequency=fs_hz,
        dtype=np.uint16,
        num_channels=num_channels,
    )
recs['unsigned_from_raw'] = si.unsigned_to_signed(recs['raw'], bit_depth=bit_depth)
print(recs['raw'].dtype)
recs['probe_from_unsigned'] = recs['unsigned_from_raw'].set_probe(npx_mapping, in_place=False)
# The other way round
recs['probe_from_raw']= recs['raw'].set_probe(npx_mapping, in_place=False)
recs['unsigned_from_probe']=  si.unsigned_to_signed(recs['probe_from_raw'], bit_depth=bit_depth)


for k, rec in recs.items():
    trace =  rec.get_traces(start_frame=0, end_frame=2, return_in_uV=False, channel_ids=[30])
    print(f"{k}: {trace[0,0]} (dtype: {rec.dtype})")

Prints:

raw: 3847 (dtype: uint16). [expected]
unsigned_from_raw: 1799 (dtype: int16) [expected]
probe_from_unsigned: -28921 (dtype: int16) [BAD expected is 1799]
probe_from_raw: 3847 (dtype: uint16) [expected]
unsigned_from_probe: 1799 (dtype: int16) [expected]

[ablot]

These are probably unrelated issues. The second is that calling self.clone in a UnsignedToSignedRecording does not keep the bit_depth property to the recording segments.