Video lagging. Not synched with video

berghoutc

Hello All. I'm using racechrono pro v3.21 on my samsung galaxy s4. Qstarz bt-818xt, elm327 obd2 reader. Just tinkering for the first time trying to overlay some data on an already overlaid video from RC pro yesterday, I waited for what seemed like an eternity for racerender to make a video for me, in Mp4 format on my reasonably new macbook pro. I tried playing the video when it finished to find that the video would roll for a second, then freeze for several seconds, all the while the audio file seemed to keep running. Any ideas? My thought is maybe my cpu can't handle the video? shrug. Any advice would be much obliged. Cheers

aol_of_RaceChrono

Haven't tried already overlaid video with racerender, maybe better use the raw videos with that. The video quality degrades on every encode cycle. Some video players like quicktime have trouble with videos overlaid with RC Pro, but VLC player works perfect and upload to services like YouTube as well.

berghoutc

What is VLC player? Not familiar. I use quicktime because I'm a mac homer! and windows MP when necessary on my surface or thinkpad. I'm tracking this weekend at Watkins Glen so I want to make sure that what I record (with my galaxy s4 camera I forgot to mention previously) I can overlay and create something nice. Any advice for optimal video speed/quality I should select in RC so that what I record will be most external hardware/software compatible?

aol_of_RaceChrono

I use mac as well VLC is the best player for mac and windows http://www.videolan.org/vlc/index.html

berghoutc

Thanks. I just downloaded. I'll let you know how things go. I should also point out that just based on the sheer enthusiasm and alacrity with which I've received support thus far from racechrono, I'll definitely be recommending this application to all of my track buddies who don't log data/make videos yet. Thanks again.

berghoutc

So I got a 720p video to run in vlc. It's a little choppy. My buddy who back country skis and records 1080p vids recommended a "class 10, high speed SD card for my galaxy s4. Have you heard of standard SD cards affecting video quality?

aol_of_RaceChrono

Sure if the SD card is too slow, then the videos will get bad. How do the raw videos look? Let's say when you play back the recordings with RaceChrono? If that is choppy it is sdcard issue. If the raw videos are perfect, but exported video is choppy then it might be codec issue of some sort.

The raw videos are located on internal memory under /DCIM/RaceChrono/ and on sdcard they are at /Android/data/com.racechrono.pro/files/Movies/RaceChrono/

berghoutc

Thanks aol! Went with a UHS-1 card and there was definitely an (albeit modest) improvement to the raw video. I got a short video running nicely on VLC on my surface pro 2. :-) the only thing I need to figure how to do at this point I think is how to synchronize my OBD and GPS data with the video which, as you well know, is being initiated in some cases 30-45 seconds after I start recording data. Racechrono pro is an overwhelmingly brilliant piece of programming technology. Bravo!

berghoutc

So I just picked up a go pro hero 3 with wifi capability. Any advice for video/data/gps syncing? I thought there was some way to auto sync the go pro cam via wifi to the data stream. Is this possible? I can wifi connect my galaxy s4 to my go pro using the go pro app. Thanks

aol_of_RaceChrono

There's no auto-sync feature. I did investigate that, but I felt it was too unreliable, as the GoPro clock was in local timezone and mostly wrong... Here's few tips how to do it manually:

1) Seek the video to a landmark such as a tunnel, gantry or finish line, and then seek the data using the areal photographs on the map screen to same place.
2) If your finish line is set to correct place, then just seek the graph to start of the lap, and the video to the crossing of the finish line
3) If you have OBD-II available, you can sync using the sound with the RPM data