Viofo A329S (3ch) appears to overload the system in Low-Bitrate parking (video "flickering")

[GPak]

Since @VIOFO-Support and @viofo is following this thread...
I noticed that video recorded in Low-Bitrate (LBR) parking mode appears "jerky/flickering."
I suspect that 3-channels with the front one recording in 4K places too heavy a load on the system for Low-Bitrate.
I’m not a video recording expert, so I asked AI: are there any advantages to lowering the A329S front camera resolution from 4K to 2K in Low-Bitrate parking mode?
Here is the AI's answer:
Lowering the Viofo A329S front camera resolution from 4K to 2K in LBR parking mode:
-Reduces processor load,
-Lowers heat generation and power consumption,
-Extends the lifespan of the memory card."
-Better video clarity under LBR - 4K video requires massive amounts of data to look good; forcing 4K into a Low-Bitrate results in heavy, blocky pixilation and compression artifacts. A 2K resolution fits that same data budget much better, often yielding a cleaner and more legible image.

These advantages may not be particularly significant in absolute terms, but still…
I think that given the car is stationary when parked - a 2K resolution for the front camera should be quite sufficient, matching the interior and rear cameras.
Currently, there is no such setting in A329S (3ch), although, if memory serves me right, some Viofo 4K models either have an option to switch to 2K or automatically switch to 2K in LBR parking mode.

Otherwise, I really like the Viofo A329S (3ch).

 

[GPak]

LBR Parking - Front Camera:

Driving - Front Camera:

LBR Parking - Rear Camera

Firware - VIOFO_A329S_V2.2_260815
LBR settings:
LED - Front camera Power only
GPS - Off
HDR - On

 

[Chuck McCoy]

Yo GPak,
Thanks for making a new thread.

I’m having a hard time seeing any issues with Front Camera Low Bitrate Parking Mode video.
Do you by any chance have a second A329S that you can film “side by side” simultaneously with?
1.) One recording Low Bitrate Parking Mode
2.) One recording Normal / Driving Mode
That’s the only way I see “differences”.

As far as dropping 4K down to 2K for parking mode, I’m not a fan.
Yes I know it can reduce;
1.) Power Consumption
2.) Heat Generation
3.) File Sizes

But I want maximum image quality at all times.
I would rather fix these 3 issues with;
1.) More Efficient Processors / Dash Cam Battery Pack with Solar Panel Integration
2.) Better Heat Dissipation
3.) Larger SD Card / SSD Capacity

This is why I leave my cameras running in Normal / Driving Mode when I go into the store for 1-3 hours, (maximum image quality).
-Chuck

 

[GPak]

Thanks Chuck,
I, too, am in favor of maximum image quality - provided the camera can deliver it reliably.
I am not really concerned about power consumption and SD card capacity – these are under my control and the parking battery and memory card capacities are more than sufficient for my needs.

However, I cannot control the camera's heat generation when using the LBR parking mode.
At work, the car sits in direct sunlight for 10 consecutive hours (sometimes I split this into two 5-hour intervals when I drive home for lunch).

I don’t have a second camera, but this is more noticeable in the LBR video if you look at the wall (pointed with arrow in the attached screenshot).
You can see a sort of “flickering/oscillation/fluctuating/shifting right and left” - I’m not sure how best to describe it.
In normal driving mode video (the first 20 seconds), the same wall is visible, and there is no image “flickering”.

To be honest, this isn't critical as long as the camera continues recording in LBR mode; however, there were two instances this summer when I found the camera turned off while parked.
It definitely wasn't due to my high-capacity LTO parking battery - I’m certain of that (I checked the status and its functionality in both cases).
I suppose the cause could have been the camera's built-in overheat protection - if such protection exists at all.
Gary

 

[lufa6977]

Thanks Chuck,
I, too, am in favor of maximum image quality - provided the camera can deliver it reliably.
I am not really concerned about power consumption and SD card capacity – these are under my control and the parking battery and memory card capacities are more than sufficient for my needs.

However, I cannot control the camera's heat generation when using the LBR parking mode.
At work, the car sits in direct sunlight for 10 consecutive hours (sometimes I split this into two 5-hour intervals when I drive home for lunch).

I don’t have a second camera, but this is more noticeable in the LBR video if you look at the wall (pointed with arrow in the attached screenshot).
You can see a sort of “flickering/oscillation/fluctuating/shifting right and left” - I’m not sure how best to describe it.
In normal driving mode video (the first 20 seconds), the same wall is visible, and there is no image “flickering”.

To be honest, this isn't critical as long as the camera continues recording in LBR mode; however, there were two instances this summer when I found the camera turned off while parked.
It definitely wasn't due to my high-capacity LTO parking battery - I’m certain of that (I checked the status and its functionality in both cases).
I suppose the cause could have been the camera's built-in overheat protection - if such protection exists at all.
Gary

Against that white wall, I can see what you are talking about. At first, I thought this effect only applied to white backgrounds/clouds in the distance, but then I noticed the bush on the near left did the same.

I would check the raw video first to see whether it shows a consistent 15 fps, or whatever fps Viofo uses for LBR. If it jumps up and down, that might be a clue for Viofo. The pattern seems to be fairly rhythmic so it does look like the process enters a loop and stays there until it gets full battery after you start the car. If I understood the issue properly.

Cyclic writing could be happening on the memory card, where a buffer fills, writes, and refills again. I have no idea if a combination of a hot memory card, wire resistance, battery voltage, and camera processor heat could be causing this stuttering effect on your video.

These Novatek processors have a built-in high-heat shutdown, so that could have stopped the recordings you mentioned.

 

[Chuck McCoy]

this is more noticeable in the LBR video if you look at the wall (pointed with arrow in the attached screenshot).
You can see a sort of “flickering/oscillation/fluctuating/shifting

Is it possible this flickering / shifting is because you have HDR enabled in parking mode?
I see HDR is OFF in driving mode.
Can you replicate this test again, but turn HDR OFF in parking mode?
I remember reading a post from @Mtz that said we should not use HDR in parking mode, but I can’t remember.

 

[GPak]

Against that white wall, I can see what you are talking about. At first, I thought this effect only applied to white backgrounds/clouds in the distance, but then I noticed the bush on the near left did the same.

I would check the raw video first to see whether it shows a consistent 15 fps, or whatever fps Viofo uses for LBR. If it jumps up and down, that might be a clue for Viofo. The pattern seems to be fairly rhythmic so it does look like the process enters a loop and stays there until it gets full battery after you start the car. If I understood the issue properly.

Cyclic writing could be happening on the memory card, where a buffer fills, writes, and refills again. I have no idea if a combination of a hot memory card, wire resistance, battery voltage, and camera processor heat could be causing this stuttering effect on your video.

These Novatek processors have a built-in high-heat shutdown, so that could have stopped the recordings you mentioned.

Thanks @lufa6977
It is more noticeable against the white wall, but the entire image is affected.
I checked the FPS in Windows7 file properties, and verified with couple of “Video Frame Rate Checker” websites.
Results are in attached images.
It is 30 FPS, but it looks like a “sort of time-lapse”.

 

[GPak]

Is it possible this flickering / shifting is because you have HDR enabled in parking mode?
I see HDR is OFF in driving mode.
Can you replicate this test again, but turn HDR OFF in parking mode?
I remember reading a post from @Mtz that said we should not use HDR in parking mode, but I can’t remember.

It's quite possible!!!
HDR is enabled on a time schedule while driving, whereas in parking mode it operates continuously, if selected. (front cam only, btw)
I will disable HDR for parking mode and repeat this test - likely on Monday.

 

[lufa6977]

HDR is interesting and a possibility. One of my tests is to park about 3 or 4 car lengths from the side of a Kentucky Fried Chicken and video the red-and-white stripes on the side wall. With the sun hitting the wall, the CMOS will see changes in the hue and intensity of the red and white stripes. Sometimes the white color completely hides the mortar lines. So as clouds move by, the wall changes color in the video based on the CMOS tuning, but my eyes, my iPhone, and my Oppo (Android) don't see that change. This effect is worse with HDR, but it has not been an effect that 'flashed' back and forth. But your wall looks like it is corrugated metal or has alternating white and dark vertical lines, so all bets are off on that one. 🙂

 

[Hack_man]

Since @VIOFO-Support and @viofo is following this thread...
I noticed the poor video quality of the front camera in Low Bitrate (LBR) parking mode; I think the combination of LBR and 4K resolution is not the best.
I’m not a video recording expert, so I asked AI: are there any advantages to lowering the A329S front camera resolution from 4K to 2K in Low Bitrate (LBR) parking mode?
Here is the AI's answer:
Lowering the Viofo A329S front camera resolution from 4K to 2K in LBR parking mode:
-Reduces processor load,
-Lowers heat generation and power consumption,
-Extends the lifespan of the memory card."
-Better video clarity under LBR - 4K video requires massive amounts of data to look good; forcing 4K into a low bitrate results in heavy, blocky pixilation and compression artifacts. A 2K resolution fits that same data budget much better, often yielding a cleaner and more legible image.

While these advantages may not be particularly significant in absolute terms, I still believe that—given the car is stationary when parked - a 2K resolution for the front camera should be quite sufficient, matching the interior and rear cameras.
Currently, there is no such setting in A329S (3ch), although, if memory serves me right, some Viofo 4K models either have an option to switch to 2K or automatically switch to 2K in LBR parking mode.

Otherwise, I really like the A329S (3-ch).

That's a great idea!

I don't see a way to configure the A229 Pro for 4K normal driving and then switch to 2K LBR for parking mode. So we would have to collect comparison data after manually changing settings.
Motion in the LBR parking video (like swaying trees) impacts the file size so the two videos would have to have the exact same conditions to be fair.

 

[GPak]

I disabled HDR in parking mode and parked at the local “Publix” to avoid corrugated white wall at work - and… “flickering/image micro shifting” were still there.
If you look at the clouds, it looks like a sort of time-lapse.

A unique feature of my setup is the remote placement of the SD card.
I’ll install that same card directly into the front unit and check if it makes any difference.

 

[GPak]

That's a great idea!

I don't see a way to configure the A229 Pro for 4K normal driving and then switch to 2K LBR for parking mode. So we would have to collect comparison data after manually changing settings.
Motion in the LBR parking video (like swaying trees) impacts the file size so the two videos would have to have the exact same conditions to be fair.

I hadn't thought of that;
I hope that if we temporarily switch the front camera resolution to 2K for the driving recording mode, it will carry over to parking mode as well.
I just want to check if LBR parking mode works better at 2K resolution.

 

[GPak]

OK,
-Moving the SD card (SanDisk Extreme PRO, 256 GB) from the external card reader to the front camera had no effect on the LBR video quality—the "flickering" persisted.
-Temporary switching the front camera resolution to 2K for standard recording also changes the resolution to 2K for parking mode.
-In my subjective view, the switch to 2K resolution has improved the video quality in LBR parking mode - the "flicker" hasn't disappeared entirely, but it has become barely noticeable.

Next, I’ll replace the SanDisk SD card with a 256 GB Viofo card. I don’t think it will make a difference, but I want to rule out all possible causes.

 

[Chuck McCoy]

I disabled HDR in parking mode and parked at the local “Publix” to avoid corrugated white wall at work - and… “flickering/image micro shifting” were still there.

I don’t think it will make a difference, but I want to rule out all possible causes.

I’m out of guesses, so I’ll stab in the dark .
1.) It is possible the “flicker / shifting” is caused by Frequency setting, (50Hz / 60Hz)?
2.) Is it possible the “flicker / shifting” is caused by EFI / RFI / EMF your custom dash cam battery pack?
3.) Does your car emit any LTE / Wi-Fi, or any other wireless protocol when the engine is off, and parked?
Again, these are just guesses.

 

[GPak]

1.) I think this is intended for electric lighting.
Currently, the setting is at 60Hz, which corresponds to the US power grid frequency. However this is easy to test.
2.) I haven't noticed any interference (EFI/RFI/EMFI) caused by my DIY battery, but this is also easy to verify:
I have a variety of portable power stations I can use for testing - including with the original Viofo cigarette lighter cable (provided the camera switches to parking mode after 5 minutes of inactivity).
3.) As far as I know there is no LTE in the car and no active Wi-Fi when the engine is off, but certain systems—such as the alarm, door locks, onboard computer, key-less entry, etc. - definitely remain active; and considering it’s a 2026 model, who knows what else might be running? Somehow, Honda knows a lot about the condition of my car. 🙂

- This brainstorming gave me another idea - I can disconnect interior and/or rear camera to unload the system and see if this improves LBR parking for the front camera.

 

[Chuck McCoy]

considering it’s a 2026 model, who knows what else might be running?

John Kiriakou

 

[GPak]

- Replacing the SanDisk Extreme PRO SD card (256 GB) with a Viofo card (256 GB) - made no difference.
- Disconnecting first just the interior camera, then just the rear camera, and finally both simultaneously (interior and rear) in LBR parking mode also resulted in no changes. (So, perhaps it isn't an excessive load on the system after all?)

Tomorrow I will test different frequency, and then different power supply.

 

[lufa6977]

- Replacing the SanDisk Extreme PRO SD card (256 GB) with a Viofo card (256 GB) - made no difference.
- Disconnecting first just the interior camera, then just the rear camera, and finally both simultaneously (interior and rear) in LBR parking mode also resulted in no changes. (So, perhaps it isn't an excessive load on the system after all?)

Tomorrow I will test different frequency, and then different power supply.

I appreciate your approach to fault isolation for finding the cause of this issue. Eliminate potential issues one by one. 👍

This may boil down to how the CMOS tuning is reacting to light intensity and reflection. I don't have an A329S, but I have never seen anything quite like this in my A129 Pro, A229 Pro, A229 Plus, or A119 Mini 2. Perhaps your CMOS is slowly giving up the ghost?

 

[Sun Storm]

I noticed that video recorded in Low-Bitrate (LBR) parking mode appears "jerky."
I suspect that 3-channels with the front one recording in 4K places too heavy a load on the system for Low-Bitrate.
I’m not a video recording expert, so I asked AI: are there any advantages to lowering the A329S front camera resolution from 4K to 2K in Low-Bitrate parking mode?
Here is the AI's answer:
Lowering the Viofo A329S front camera resolution from 4K to 2K in LBR parking mode:
-Reduces processor load,
-Lowers heat generation and power consumption,
-Extends the lifespan of the memory card."
-Better video clarity under LBR - 4K video requires massive amounts of data to look good; forcing 4K into a Low-Bitrate results in heavy, blocky pixilation and compression artifacts. A 2K resolution fits that same data budget much better, often yielding a cleaner and more legible image.

These advantages may not be particularly significant in absolute terms, but still…
I think that given the car is stationary when parked - a 2K resolution for the front camera should be quite sufficient, matching the interior and rear cameras.
Currently, there is no such setting in A329S (3ch), although, if memory serves me right, some Viofo 4K models either have an option to switch to 2K or automatically switch to 2K in LBR parking mode.

Otherwise, I really like the Viofo A329S (3ch).

Justs wanted to let you know that you are not alone.
When I zoom in on the video on my phone I can see it's not only the corrugated wall, but can see this on the floor etc.

 

[GPak]

Justs wanted to let you know that you are not alone.
When I zoom in on the video on my phone I can see it's not only the corrugated wall, but can see this on the floor etc.

Thanks for posting,
So, it is not just me...
I tried changing the frequency from 60 Hz to 50 Hz and back—to no avail: the "flickering" didn't go away.