No overlay anywhere - GoPro 7 + Android

[flyingflatfour]

Winter has arrived so it’s time to look back at the trackday season

I’ve been using HLT on several occasions, in conjunction with a GoPro Hero 7 BE as the only camera and a BT OBD adaptor.

The camera was setup for best quality at 4K/60fps producing large HEVC encoded files in 4Gb chunks.

To assemble these chunks together, and since I’ve read that there were problems with overlaying the Hero 7 original videos, I‘ve used Shotcut software on my PC to export a single h264 .mp4 file for the first track session I want to overlay, then import it onto my Samsung Galaxy S10E (Android 9) internal’s memory.

Within HLT I have then relinked this file to the 7 laps of the session, which worked perfectly.

The issue I have now is that the overlay feature is inoperative, both as a real-time feature in the video play window, as well as after exporting a series of laps and thus creating an overlaid video.

I have checked that the lap data was valid as well as the vehicle properties. All overlay options were selected except référence lap. No errors showing on the overlay screen.

Here are a few screenshots to illustrate (I hope you can still figure things out despite the interface being in french)

1. Overview of the lap I want to overlay


2. Play view before creating an overlay: no real-time overlay preview


3. Overlay settings menu


4. Lap details after overlay was successfully created


5. Play view after overlay created: still no overlay visible


6. Video details after overlay created


Additional information: the laps were recorded on another Android phone running 8.1. Recently switched to the Galaxy and exported/imported the database successfully it seems.

Suggestions: update the video documentation to reflect the current interfaces with high-quality screenshots. Specify any limitations pertaining to video files: size, resolution, framerate, encoding, format...

[Harry]

Hello,

The problem you experience is most probably not related to the HERO7 issue at all. See the Known Bugs section here - first item.

On the work around using real time overlays: at least for the lap shown in the snapshot, you had overlaid the video already. You can see this in the row under the preview: LapTimer considers this video an overlaid video - although it misses the gauges and data. When pressing Play, LapTimer "thinks" the overlay is there already and doesn't add gauges in real time. To get this part working, please return to the original video version by pressing the Original / Revert button next to the Play button. This will re-associate the original video which is considered "overlay free". When pressing Play now, LapTimer should bring up the video including real time overlays. Tested with a 32bit Android 7.1 and a 64bit Android 10 device today.

I'm sorry for the inconvenience.

- Harry

[flyingflatfour]

Hi Harry,

So I guess I just have to wait for on update on the software encoder...

Concerning the real-time overlay not working, I have being going back and forth several times, however the first screenshot shows the situation before overlaying, or after restoring to original (video brute + exporter visible)

I can confirm that there is still no real time overlay happening.

[flyingflatfour]

BTW, I can confirm the code 16 error when attempting to use software encoding

Troubleshooting steps would be appreciated to try to fix real time overlays, thanks in advance

[drbond]

Yes, I am getting the same error 16 code without data overlay on video on my Android 9.0. So, I tried to update the Android to see if that fixed it, and now every lap says "no video", although the video is still in the phone, as I can access it when I connect the Android to my PC.

[flyingflatfour]

Problem fixed with latest update. Hardware encoding works just fine as well. Thanks!

[flyingflatfour]

Amendment to previous post: the hardware encoding tends to crash when exporting more than three laps in a row.

In this case we are talking of about 7 min of footage at 4K/60fps resolution.

Also, the video qualilty of the overlaid video appears significantly decreased compared to the original file.

Looking into each video details, I found the following:

Source video: 4K/59.94 fixed fps, VBR (average 12 Mbits/s), YUV 8bit -> nice visual quality and colours, 1.1 Gb file for 11:34min of footage

Overlaid video of 3 laps: 4K/59.94 variable FPS, VBR (average 70 Mbits/s), YUV 8bit -> horrible colours (looks like 256 colours!) otherwise ok , 3.7 Gb file for 7:12min of footage.

Can we look into this together with more detail?

Thanks

[Harry]

Hello,

I played a lot with the quality settings, it is difficult. You can try increasing the bitrate multiplier in Expert Settings / Video Tweaks to a higher value like 2.0.

In case you have enough space, use software encoding. Although it uses mpeg4/2 instead of h.264 encoding, it will preserve quality a lot better (at the price of huge files).

Harry

[flyingflatfour]

Hi Harry,

Following your instructions I have changed the pixel setting to 0.2 which gives around 14 Mbps bitrate (comparable to the original) and a much smaller file size.

Still the colour issue remains. Please see screenshots of the problem, as well as file details.









As you can see it looks like the original colour depth was somehow destroyed during the decoding/encoding process...

Concerning the crash issue using hardware encoding for multiple laps, any idea ? The app just reboots itself with no error message.

Are you planning on releasing a stand-alone Windows based analysis and export/overlay program? I believe this would make things much more stable and usable especially for larger 4K files...

Best wishes for 2020!

[Harry]

Hardware encoding needs to make some assumptions on the memory layout of your smartphone. See item 9 (at the time of writing) of viewtopic.php?f=39&t=1693.
Furthermore, LapTimer's hardware encoding approach uses a 16bit per color pixel format during an intermediate processing step (RGB565 format). This may rasterize finer color changes and lead to this artifacts. Please switch to software encoding as proposed to work around.

Today, memory sizes and processing speeds of smartphones are far beyond what is required for this exercise. The problem with Android is that video processing has not been a first class citizen here for a long time. I had a hard time to introduce overlaying for all the different Android versions still around. I may return to this topic at some point in time. You can get an idea of what is possible with well integrated hard- and software when looking into iOS. With a recent device, LapTimer requires a third(!) of the video length for overlaying. I considered creating an overlaid version of the video in background while driving already.

- Harry