Test fit file

test.py

from fitparse import FitFile
from collections import OrderedDict
import datetime

UTC_REFERENCE = 631065600

fitfile = FitFile('lagny_fim.fit')
data = {}
for _, msg in enumerate(fitfile.get_messages('hr')):

    if msg.header.local_mesg_num == 12:
        last_event_timestamp = msg.get('event_timestamp').raw_value
        raw_timestamp = msg.get('timestamp').raw_value
        #print('raw_timestamp', raw_timestamp)
        continue

    timestamps = []
    octets = msg.get('event_timestamp_12').raw_value
    idx = 0
    odd = 0

    while octets and idx < len(octets) - 1:
        last_event_timestamp12 = last_event_timestamp & 0xFFF;

        if not odd % 2:
            next_event_timestamp12 = octets[idx] + ((octets[idx + 1] & 0xF) << 8)
            last_event_timestamp = (last_event_timestamp & 0xFFFFF000) + next_event_timestamp12
        else:
            next_event_timestamp12 = 16 * octets[idx + 1] + ((octets[idx] & 0xF0) >> 4)
            last_event_timestamp = (last_event_timestamp & 0xFFFFF000) + next_event_timestamp12
            idx += 1

        if next_event_timestamp12 < last_event_timestamp12:
            last_event_timestamp += 0x1000

        timestamps.append(UTC_REFERENCE + raw_timestamp + (last_event_timestamp / 1024.0) / 1024)

        idx += 1
        odd += 1

    for date, hr in zip(timestamps, msg.get('filtered_bpm').value):
        if date in data:
            data[date].append(hr)
        else:
            data[date] = [hr]

data = {k: sum(v) / len(v) for k, v in data.items()}
data = OrderedDict(sorted(data.items()))

for date, hr in data.items():
    print("%s,%s" % (get_date(date), hr))