QZ FIT file start timestamp inconsistent with Zwift

[victorypoint]

@cagnulein, now that we have a consistent way to synchronize that start of activities between Zwift and QZ (ensure speed is 0 then increase to start FIT file recording at the same time), I'm finding a strange inconsistency with the start timestamp in the QZ FIT file. This is affecting the ability to accurately merge data between the two FIT files (e.g. latitude, longitude, elevation, power, etc).

For example, here's results of a recent test using QZ fake treadmill mode:

• Launch QZ in paused state - 2:06pm
• Launch Zwift and begin a manual run - 2:07pm - avatar stands still waiting for speed
• Hit QZ Start button - 2:11pm - avatar stands still waiting for speed
• Hit QZ preset speed button 10kph - 2:14pm - avatar begins to move
• Hit QZ Stop button, end Zwift run, exit both QZ and Zwift - 2:22pm
• Examine Zwift and QZ FIT files:
  • Zwift starting timestamp - 2:14:05pm - this appears to be when QZ speed preset button was pressed
  • QZ starting timestamp - 2:17:01pm - this is strange and shows QZ is ahead by 2 minutes 56 seconds
  • 0QZ starting timestamp - 2:17:01pm
  • 1QZ starting timestamp - 2:17:01pm

I've retested this several times and always arrive at a strange delayed QZ starting timestamp. Any help resolving this is greatly appreciated.

FIT files attached. test4.zip

[victorypoint]

@cagnulein, let me test this idea - single QZ FIT file for multiple Zwift activities and see if FIT merge works.

[victorypoint]

But I was thinking: is it really necesseary? I mean since the Zwift activity has an end, we can simple discard all the remaining qz activity from the zwift one (the qz activity will be probably longer than the zwift one, but we can simply cut the remaining off, isn't it?)

@cagnulein, ok I tested this theory and you're a genius! Have I ever mentioned that before? 🤣🤣

Here's what I did to test multiple Zwift activities/single QZ session. A typical scenario is to start on May Field, jump to a run event, then exit to main Zwift screen and perhaps do other runs, workouts, meetups while staying in Zwift with QZ running in the background.

• Use QZ fake treadmill mode
• Launch QZ and Zwift on PC
• Start in bike mode for auto-incline and bike for a short distance to test
• Create and join run meetup. Run for a km or more in run meetup
• Exit and go to May Field for a km or more
• Jump to run meetup again and run for a km or more
• Exit and go to London Classique and run for a bit
• Exit and join Watopia Chili Pepper pacer bot and run for a bit
• Jump to run meetup again and run for a bit
• End and exit Zwift and QZ
• There may have been a few more activities in there - I can't remember 😂
• Collect single QZ FIT file and all Zwift activity FIT files and run merge process - it worked!! The only downside as we noted earlier is that QZ metrics transfer over to each workout including elevation gain, elapsed time, etc.

Here are elevation graphs of resulting FIT file merges for each Zwift activity. Blue is Zwift FIT, green is Zwift/QZ/elevation merge FIT. Note that the first graph is the bike ride where Zwift FIT file always has correct terrain elevation. The remaining graphs are runs where Zwift elevation is incorrect (in blue) and need to be corrected with QZ elevation (green):

[cagnulein]

so your java skills are still strong! 💪

[cagnulein]

so I guess we can reopen this https://github.com/cagnulein/qdomyos-zwift/pull/1369#issuecomment-1476323034

[cagnulein]

my idea is adding a command line argument to specify the zwift fit file directories. So qz can get the lastest one and opening it each seconds or so? what do you think?

[victorypoint]

my idea is adding a command line argument to specify the zwift fit file directories. So qz can get the lastest one and opening it each seconds or so? what do you think?

Incredible idea! This just after I came up with a Windows batch solution using the Java option 😂 - https://github.com/victorypoint/RepairZwiftFIT

[stale[bot]]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[victorypoint]

Keep this alive please!

[cagnulein]

about this @victorypoint should we proceed with opening the fit file in real time? do you think it's doable?

[victorypoint]

about this @victorypoint should we proceed with opening the fit file in real time? do you think it's doable?

@cagnulein, yes, I believe it's doable. The active FIT file is readable in realtime which is what we want to obtain coordinates for each timestamp.

[cagnulein]

@victorypoint can you attach a fit file from a workout here? I mean getting it while you're running, so i can check that the file is closed. Also how often this file is updated from zwift?

[stale[bot]]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[victorypoint]

@victorypoint can you attach a fit file from a workout here? I mean getting it while you're running, so i can check that the file is closed. Also how often this file is updated from zwift?

@cagnulein, so sorry for the delay on this! I've been so busy with the python stuff! 😮. So I just did a workout as follows:

• Zwift Windows with QZ fake treadmill. FIT file path is - C:\Users\alanu\Documents\Zwift\Activities\
• I grabbed all in progress FIT files for analysis at 3 minute intervals - inProgressActivity.fit and 2023-04-27-11-54-03.fit
• I used FIT file viewer to inspect files - https://www.fitfileviewer.com/
• Grabbed inProgressActivity.fit snapshots every 3 minutes
  • inProgressActivity0.fit, 1, 2, 3 - only one record - 8/25/1992, 2:08:16 PM
  • inProgressActivity4.fit - 600 records with timestamp every second - 4/27/2023, 11:56:17 AM - 4/27/2023, 12:06:16 PM
• Grabbed 2023-04-27-11-54-03.fit snapshots every 3 minutes as well
  • 2023-04-27-11-54-03-1.fit - 109 records every second - 4/27/2023, 11:56:17 AM - 4/27/2023, 11:58:05 AM
  • 2023-04-27-11-54-03-2.fit - 331 records every second - 4/27/2023, 11:56:17 AM- 4/27/2023, 12:01:47 PM
  • 2023-04-27-11-54-03-3.fit - 441 records every second - 4/27/2023, 11:56:17 AM - 4/27/2023, 12:03:37 PM
  • 2023-04-27-11-54-03-4.fit - 710 records every second - 4/27/2023, 11:56:17 AM - 4/27/2023, 12:08:05 PM

So it looks like my previous theory that the inProgressActivity.fit file updates in real-time is wrong - it appears to update every 10 minutes or so? However, the timestamped FIT file does update in real-time I believe every second and is readable during workouts.

[cagnulein]

@victorypoint are you still interested on this? now with the zwift api we can collect gps data!

[cagnulein]

the only issue is that for now the windows build doesn't support the zwift api (i have to find the time to add them), but if you want I can add this on the android or ios build

[victorypoint]

@cagnulein, yes! Absolutely! I can test on all platforms so good to go 👍

[cagnulein]

ok i will try to do first on ios, i need to convert the X and Y from zwift to gps coordinates, i found that there is a conversion to do for the different worlds

[cagnulein]

@victorypoint i thought it could be easy instead i'm struggling to find information about how to translate coordinates from zwift system to the world system. https://github.com/sandermvanvliet/RoadCaptain/blob/d8ec891349212d2a8ef2691925376712680e0bc4/src/RoadCaptain/TrackPoint.cs#L256 seems to be the most update resource but his conversion doesn't match at all. Also I don't understand if this conversion is actually working on RoadCaptain. Do you have some information about this?

I have X and Y zwift coordinates in realtime but I can't transform them to real GPS coordinates

[victorypoint]

@cagnulein, ok I'll check it out in the next few days. I haven't used roadcaptain yet so need to study it a bit.