how to deal with incomplete file during power loss

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chilioil

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Hi, thanks for reading. I just bought the s1 4k and I just realized this unit does not have battery/supercap so when it lost power it just shuts down. I am a little confused since I only plan to use it with cigarette 12v power and what if I got into an accident that the power got cut off. Do I lose the actual moment of truth then it matters the most?

I was doing a testing near my desk with usb c power plugged into its data/power port, I noticed that each time I pull the power plug, and then plug it back on later, it says the SD card needs to be formatted. So I took the card out on my PC and I saw they have a tmp file in the INF folder, that I don't know what to do with it...

That feels like a real bummer...
 
update: i just noticed that my firmware is very old, 1.09 I remember. So I updated to 1.40 and I noticed that every time I turn on the dash cam it says recovering last video and it somehow "repaired" the last .tmp file.

Though, I tested and it seems to always miss about 1s of recording. 🙁
 
chilioil said:
Hi, thanks for reading. I just bought the s1 4k and I just realized this unit does not have battery/supercap so when it lost power it just shuts down. I am a little confused since I only plan to use it with cigarette 12v power and what if I got into an accident that the power got cut off. Do I lose the actual moment of truth then it matters the most?

I was doing a testing near my desk with usb c power plugged into its data/power port, I noticed that each time I pull the power plug, and then plug it back on later, it says the SD card needs to be formatted. So I took the card out on my PC and I saw they have a tmp file in the INF folder, that I don't know what to do with it...

That feels like a real bummer...
Click to expand...
Hi This is James at VUEROID.

Thank you very much for purchasing the S1 4K.

Let me explain this part in a bit more detail.

Yes, that is correct. The S1 4K does not use battery components such as a super capacitor. Depending on the quality of the component, they can negatively affect thermal characteristics and are also difficult to use permanently over a long period of time, so we try to avoid using them whenever possible. (A very long time ago, Vueroid did develop models using batteries as well.)

The Vueroid S1 4K uses our self-developed dashcam-specific file system called TFF.
It is essentially a modified form of the standard FAT32 file system optimized specifically for dashcam usage.

To explain it simply, when an SD card is first inserted into the VUEROID S1 4K and the device boots up, formatting is performed. During this process, temporary files matching the size of 1-minute video clips are pre-created across the SD card according to its capacity.
After that, the recorded footage is written by filling these pre-created temporary files.
Because of this structure, even immediately after formatting — without recording anything at all — you will notice that the SD card already appears almost full.

In general, when dashcams use FAT32 as the storage structure, files gradually become fragmented over time as usage increases. (The same thing happens with normal PC HDDs as well.)
Performance gradually degrades, and the lifespan of the NAND flash inside the SD card is shortened more and more. That is why most dashcam brands recommend regular SD card maintenance and formatting.

With VUEROID’s TFF, however, you do not need to worry about those issues at all. It is designed to be format-free, and through journaling, file corruption does not occur. In addition, it has the effect of extending SD card lifespan by at least 30% or more.
So this is really not something you need to feel disappointed about, and I would appreciate it if you could reconsider your impression of this aspect.

And to share one more piece of good news: TFF will be upgraded further in the next firmware update.
Until now, the last file at the moment power was cut off was designed to be recoverable after rebooting or through the VUEROID PC Viewer.
With this upcoming update, even without any battery component, the final file will now be saved in a fully playable state immediately.

We hope you will look forward to the next firmware update and verify this improvement once it becomes available.

Have a good day~
 
That is brilliant to hear and I appreciate the prompt response very much 🙂 Do you happen to have the ETA for the next version? I know it might be hard to predict but a general ballpark will be welcomed 🙂
 
Also sorry to ask one more question: do you happen to know in the next version will the file keep the last 1 second after power cut? I am ok even now with needing the dashcam to restart to recover the file or using the software, but I am a little worried about the loss of the 1s of video before power cut since it might contain important footage when it is needed. Thanks 😉
 
chilioil said:
update: i just noticed that my firmware is very old, 1.09 I remember. So I updated to 1.40 and I noticed that every time I turn on the dash cam it says recovering last video and it somehow "repaired" the last .tmp file.

Though, I tested and it seems to always miss about 1s of recording. 🙁
Click to expand...
Hi~~ James again.

Could you explain the “missing 1 second” a bit more specifically?

I would like to understand whether it is the beginning of the recorded footage or the final 1 second that appears to be missing, and whether this occurs under specific lighting conditions.

It would also be helpful if you could share your current configuration information, such as:

  • Number of channels
  • Bitrate settings
  • Resolution and frame rate settings
  • Whether HDR or IPC is enabled
And ideally, if you could share the footage of VUEROID S1 4K where you believe the 1 second is missing, that would help the most.
If you send me a shared folder link or email the files directly to me, I should be able to analyze the issue and provide feedback.
I will send you my email address via DM.

Have a good day~
 
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Hi James, thanks again.

Let me explain my configuration since I just got it today and haven't installed it yet. My test was only for the main unit without the other two cameras, and I picked default for every thing, which I believe to be

1CH
normal/medium bitrate
4k30ps
(not sure about HDR since I haven't even looked into the menu yet)

I did the test on my desk: I was recording a clock and I time the moment when I pull the USB power plug. At this time there would be a .tmp file, but without taking the SD card out, I waited 10+ seconds, then plug in the USB cable again, let it boot with the "recovering last file" message on the screen then waited another 10+ seconds

I then turn off the camera, take out the SD card into PC, I saw the last file was successfully recovered. However, if I replay it, I noticed that it was cut off about 1s before the clock time I counted.

This is an Sandisk 512GB extreme microSD card. And this behavior is reliably reproducible after multiple tests.
 
chilioil said:
That is brilliant to hear and I appreciate the prompt response very much 🙂 Do you happen to have the ETA for the next version? I know it might be hard to predict but a general ballpark will be welcomed 🙂
Click to expand...
I can't confirm the exact date of the next VEUROID S1 4K F/W update, but since the feature development for TFF has been done, it should be soon or later.
 
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chilioil said:
Also sorry to ask one more question: do you happen to know in the next version will the file keep the last 1 second after power cut? I am ok even now with needing the dashcam to restart to recover the file or using the software, but I am a little worried about the loss of the 1s of video before power cut since it might contain important footage when it is needed. Thanks 😉
Click to expand...
Hi,

Once the update is completed, the new file system may possibly lose a maximum of 0.99 seconds when a sudden power cut occurs, but that would be the worst-case scenario.
Statistically speaking, the average loss across most cases should be around 0.5 seconds because it is the mid-value of the possibilities.

So, the S1 4K cannot preserve every single frame from the very last moment during a sudden power loss.
With the updated file system, a very small portion of the final moment may be lost, but in return, the last recorded file will remain playable consistently and reliably.
And, Yes there is no battery, which is troublesome.

If we want to reduce the loss at the very last moment, we would need to update the file journal more frequently. Currently, it is updated once per second. However, increasing the update frequency would add more burden to the system.
In that case, we may need to compromise the performance of other features.

Indeed, both the conventional FAT file system with a super capacitor structure and VUEROID's TFF each have their own advantages and disadvantages.
However, the strengths of TFF are so significant that I still believe its advantages more than sufficiently outweigh its drawbacks.

Thank you~~!
And have a good day~
James
 
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Thanks a lot James, that makes total sense from technical perspective and I really appreciate the explanation. I remember in another thread someone mentioned that if the dashcam is hardwired, even with current firmware it can still complete the latest file just fine when it transits from driving mode to park mode, since it is not a "sudden power loss". May I ask if in this case I will have the last bit of video saved? Because I thought that investing in a battery pack might not only be handy for long term parking mode, but also solve the last second problem in the case of a sudden car power loss, if my guess is true.

Thanks again!
 
You are the owner of the VUEROID dashcam.
I am simply carrying out customer care activities here, which is obviously part of what I should be doing.
Thank you very much for your kind words, though. 😉

Vehicles provide separate constant power and ACC power lines. In other words, the power state when the ignition is on and when it is off is handled separately.
If power is supplied using a hardwiring cable, then yes — whenever the ignition is turned off for any reason, the dashcam would naturally switch to parking mode and continue recording.

However, as I mentioned in the thread, if power is physically interrupted for any reason — for example, if a battery terminal breaks, a battery power cable is disconnected, or the ECU forcibly shuts down electrical power due to an impact — then the power supplied through the hardwiring cable would also be cut off at the same time, resulting in the same outcome.

You are welcome~~!!
James
 
This is only my own speculation and assumption, but I thought it might be worth discussing together.
In what situations would a dashcam suddenly lose power during driving or in an accident?

You mentioned that you are using a single-channel product powered through a cigarette lighter power cable.
Of course, the worst-case scenario would be a power shutdown caused by a vehicle collision.
Depending on the severity of the accident, power may not always be cut off, but I looked into what generally happens in such situations.
It appears that an accident severe enough to cut vehicle power would usually need to be at least serious enough to deploy the airbags.

The time between the collision and the actual electrical shutdown is commonly described as being somewhere between 0.1 and 1 second.

- Crash detection: within a few milliseconds
- Airbag deployment: approximately 20–50 ms
- ECU safety response: tens to hundreds of milliseconds
- Electrical shutdown: often within 0.1–1 second

Coincidentally, these figures are very close to the timing range we have been estimating that I explained to you about the TFF upgrade Ver.
In other words, I believe it can be understood that there is a very high possibility that the footage up until the moment of impact would still be fully captured.

Of course, this does not apply to every situation, but I wanted to share what I found in case it helps relieve some of your concerns.

Have a great day~
VUEROID
 
Thanks a lot James, yeah I agree I was basically just splitting the hair over this topic I agree with your analysis on the timing in a typical situation and like you said, what matters is in fact a moment before collision (who did what), and the collision itself isn't usually that important in determining responsibility.

Like you said, when the car switch to parking mode in daily routine, it will keep working and it sounds like no video will be missing at all. In that case I have a theory that if one uses a 3rd party battery pack, no matter if the car main battery is cut or not. No video will be lost since the battery pack keeps working and dashcam would just think it enters parking mode. 🙂

Thanks again for the explanation! 🙂
 
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