There are two issues I'm running into using video with GoPro4. First, it seems like the laptimer chooses to cut the video at 3.73GB. I have many videos of exactly this same size. I can generally get 25 minutes at 720P 30fps or less with higher resolutions or higher fps. Past this video size it gets cut into another video. Second, when I try to transfer videos this large through GoPro4 WiFi it runs for 12 hours+ and still cannot transfer the video to the phone for overlay.
As a fix, I manually save the 3.73gb to the video directory, but I don't know what to do with the second video. Furthermore, the time alignment is poor, see here for my video:
https://www.youtube.com/watch?v=eLl9Ih1VlNs
3.73 GB max video size, transfer timeout w/ WiFi with GoPro4
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SBC_and_a_stick
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Re: 3.73 GB max video size, transfer timeout w/ WiFi with Go
Videos are cut into 4GB fragments by the HERO itself. This is due to typical file size constraints on SD cards. LapTimer has no influence on this process. You can concatenate your video fragments using some video file editor on your desktop. LapTimer itself will be able to process long videos. Handling files of this size is usually cumbersome, so I'd recommend to work around some way (e.g. by using 720p). When joining fragments, make sure you do not get extra frames or miss frames because this will screw up timing information for the joined video.
It is possible to overlay laps covered by the first video segment with correct synchronization. For later video fragments, you need to either join videos (see above), or set your own lap / fragment synchronization as described in LapTimer's Video Documentation (see www.gps-laptimer.de/documentation). In case the default lap / video timing seems to be out of sync nevertheless, please consider to adjust LapTimer's Expert Setting "Overlay Synchronization / Video" to something different than 1 second. LapTimer comes with a reasonable default for video / lap sync, but the delay occurring during video start may vary depending on your smartphone / action cam. Search for "sensor delay" here on the forum, there are plenty of articles.
Finally, direct video downloads are not reliable for large videos. The HERO4 is going to sleep mode after some minutes breaking LapTimer's attempt to download the video. Sleep mode is not visible from the outside except the WiFi connection between smartphone and H4 will drop. With GoPro's current 3rd party API, it is not possible to send the stay alive signals used by GoPro's own app.
Workaround: use the manual (and much faster) transfer using iTunes File Sharing described in the above Video Documentation, or use GoPro's app to download the video. Do not forget to Re-Link the downloaded video. Again, this is described in the docs in details.
I hope that helps.
- Harry
It is possible to overlay laps covered by the first video segment with correct synchronization. For later video fragments, you need to either join videos (see above), or set your own lap / fragment synchronization as described in LapTimer's Video Documentation (see www.gps-laptimer.de/documentation). In case the default lap / video timing seems to be out of sync nevertheless, please consider to adjust LapTimer's Expert Setting "Overlay Synchronization / Video" to something different than 1 second. LapTimer comes with a reasonable default for video / lap sync, but the delay occurring during video start may vary depending on your smartphone / action cam. Search for "sensor delay" here on the forum, there are plenty of articles.
Finally, direct video downloads are not reliable for large videos. The HERO4 is going to sleep mode after some minutes breaking LapTimer's attempt to download the video. Sleep mode is not visible from the outside except the WiFi connection between smartphone and H4 will drop. With GoPro's current 3rd party API, it is not possible to send the stay alive signals used by GoPro's own app.
Workaround: use the manual (and much faster) transfer using iTunes File Sharing described in the above Video Documentation, or use GoPro's app to download the video. Do not forget to Re-Link the downloaded video. Again, this is described in the docs in details.
I hope that helps.
- Harry
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SBC_and_a_stick
- Fewer than 10 Posts
- Posts: 5
- Joined: Thu Dec 03, 2015 11:53 pm
Re: 3.73 GB max video size, transfer timeout w/ WiFi with Go
Very helpful Harry, thank you. I'm going to try to search for "sensor delay." That's really the more bothersome part. Otherwise, I got a 26 minute long video which will be more than sufficient for 99% of the laps. It only cut out the last lap and the cool down lap. Manual transfer by swapping SD cards in a laptop USB port seems very quick and easy to move video around.
The manual transfer of video by mounting SD cards on laptop is about a 10 minute gig, so that's quick. The WiFi only works for ~1.7 GB files from what I could tell and that lasts ~4 hours. With the 3.73 GB file the WiFi does stay connected, I can see the transfer arrows showing traffic the entire time, both the phone and GoPro are hot to the touch, but it never finishes. Anyway, hope that helps. I'll move them manually.
The manual transfer of video by mounting SD cards on laptop is about a 10 minute gig, so that's quick. The WiFi only works for ~1.7 GB files from what I could tell and that lasts ~4 hours. With the 3.73 GB file the WiFi does stay connected, I can see the transfer arrows showing traffic the entire time, both the phone and GoPro are hot to the touch, but it never finishes. Anyway, hope that helps. I'll move them manually.