Trace cleanup

[henrygab]

Some of the .pm3 sample traces failed to cleanly convert to one-byte-per-sample binary files.

For five of the files, the values spanned 256 values, but were not in the range [-128 .. 127]. These files were read, and each sample was offset by the corresponding amount.

For the file lf_Keri.pm3, the samples were in the range [-508 .. 491] (1000 value range). For this file, each sample was divided by four and then adjusted by +1 (to center the values). The data plot in the pm3 client now shows discernible changes in amplitude.

With this PR, all the .pm3 files now store single-byte values for each sample in the range [-128,127]. This simplifies conversion to other formats (including binary).

All changes were done programmatically. The python function of note was:

Python function used

def scale_file_values_to_byte_range(infile: Path, outfile: Path, smallestValue: int, largestValue: int):

    range = largestValue - smallestValue + 1
    print(f"Adjusting file {infile} to byte range, was [{smallestValue}..{largestValue}] / {range}")

    # Probably could map the integer ranges, but only one file needed this,
    # and it was using a range of 1000 values, which is really close to 1024,
    # so ... good enough
    divisor = 1
    while range > 256:
        range /= 2
        divisor *= 2
        largestValue /= 2
        smallestValue /= 2

    offset = int(127 - largestValue)
    if range < 256:
        offset -= int((256-range)/2)

    print(f"Dividing by {divisor}, then offsetting by {offset} for file {infile} --> {outfile}")

    with outfile.open(mode="wt", encoding=None) as out:
        for line in infile.open():
            i = int(line.rstrip())
            i = int(i + offset)
            i = int(i / divisor)
            out.write(f"{i}\n")

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