Resolution and bitrate calculations: What do you run your A119 V3 at?

[Privateer]

Hi,

Based on what I've read on this forum, I have bought a Viofo A119 V3 to replace my RoadHawk HD2. I haven't yet installed the Viofo but I have been experimenting with the resolution and bitrate settings to gauge the file storage requirements and the theoretical maximum recording time for 32 GB, 64 GB, and 128 GB micro SD cards.

Please note that the files sizes are what I see on a Macbook Pro and they will be different to file sizes seen on a Windows PC. I'm no expert but I believe that it's because of the filesystem as Windows uses the standard GB while Macs use a GB = 1,000,000,000 bytes. In my calculations I've used 1 GB = 1,024 MB. Also, these figures don't take into consideration any free space needed on the card by the dashcam. Therefore my calculations are for a rough guide only and not to be taken as accurate!

RoadHawk HD2 (HDR on):

Resolution	FPS	Bitrate	Bitrate (Mbit/s)	Filesize (MB) per minute	Hours on 32 GB	Hours on 64 GB	Hours on 128 GB
1920x1080	29.97	Very High	12.19 to 16.32	126 or 105 MB	4:20 to 5:12	8:40 to 10:24	17:20 to 20:48

NB the RoadHawk HD2, when set to 1920x1080@30 with the highest bitrate, produces a file size of either 105 MB or 126 MB per minute. On a 64 GB card, I expect to get around 9 hours recording which matches the calculations.




Viofo A119 V3 (WDR on):

Resolution	FPS	Bitrate	Bitrate (Mbit/s)	Filesize (MB) per minute	Hours on 32 GB	Hours on 64 GB	Hours on 128 GB
1920x1080	30	Low	16.48 Mbit/s	127.5	4:17	8:34	17:08
1920x1080	30	Medium	18.53 Mbit/s	143.1	3:48	7:37	15:15
1920x1080	30	High	22.62 Mbit/s	174.3	3:07	6:15	12:31
2560x1440	30	Low	18.53 Mbit/s	143.1	3:48	7:37	15:15
2560x1440	30	Medium	25.90 Mbit/s	199.3	2:44	5:28	10:57
2560x1440	30	High	30.41 Mbit/s	233.7	2:20	4:40	9:20

Today, 5th December 2019, I added the calculations for 60 fps on 1920x1080

Resolution	FPS	Bitrate	Bitrate (Mbit/s)	Filesize (MB) per minute	Hours on 32 GB	Hours on 64 GB	Hours on 128 GB
1920x1080	60	Low	16.48 Mbit/s	127.5	4:17	8:34	17:08
1920x1080	60	Medium	20.57 Mbit/s	158.7	3:26	6:52	13:45
1920x1080	60	High	24.67 Mbit/s	190.0	2:52	5:44	11:29

When I fit the Viofo, I'm thinking of trying it at 2560x1440@30 with a low bitrate (WDR on) which should give me a files size of 143.1 MB / Minute and roughly 7 hours 30 minutes on a 64 GB card.

I drive daytime and night time. What sort of picture should I expect?

What do resolution and bitrate do you use and why?

NB I'm presuming that most people use 30FPS unless they're wanting slow-motion capability.

Many thanks,

 

[LateralNW]

Hi,

Based on what I've read on this forum, I have bought a Viofo A119 V3 to replace my RoadHawk HD2. I haven't yet installed the Viofo but I have been experimenting with the resolution and bitrate settings to gauge the file storage requirements and the theoretical maximum recording time for 32 GB, 64 GB, and 128 GB micro SD cards.

Please note that the files sizes are what I see on a Macbook Pro and they will be different to file sizes seen on a Windows PC. I'm no expert but I believe that it's because of the filesystem as Windows uses the standard GB while Macs use a GB = 1,000,000,000 bytes. In my calculations I've used 1 GB = 1,024 MB. Also, these figures don't take into consideration any free space needed on the card by the dashcam. Therefore my calculations are for a rough guide only and not to be taken as accurate!

RoadHawk HD2 (HDR on):

Resolution	FPS	Bitrate	File size per minute	Hours on 32 GB	Hours on 64 GB	Hours on 128 GB
1920x1080	30	High	126 MB or 105 MB	4:20 to 5:12	8:40 to 10:24	17:20 to 20:48

NB the RoadHawk HD2, when set to 1920x1080@30 with the highest bitrate, produces a file size of either 105 MB or 126 MB per minute. On a 64 GB card, I expect to get around 9 hours recording which matches the calculations.





Viofo A119 V3 (WDR on):

Resolution	FPS	Bitrate	File size per minute	Hours on 32 GB	Hours on 64 GB	Hours on 128 GB
1920x1080	30	Low	127.5 MB / Minute	4:17	8:34	17:08
1920x1080	30	Medium	143.1 MB / Minute	3:48	7:37	15:15
1920x1080	30	High	174.3 MB / Minute	3:07	6:15	12:31
2560x1440	30	Low	143.1 MB / Minute	3:48	7:37	15:15
2560x1440	30	Medium	199.3 MB / Minute	2:44	5:28	10:57
2560x1440	30	High	233.7 MB / Minute	2:20	4:40	9:20

When I fit the Viofo, I'm thinking of trying it at 2560x1440@30 with a low bitrate (WDR on) which should give me a files size of 143.1 MB / Minute and roughly 7 hours 30 minutes on a 64 GB card.




I drive daytime and night time. What sort of picture should I expect?

What do resolution and bitrate do you use and why?

NB I'm presuming that most people use 30FPS unless they're wanting slow-motion capability.

Many thanks,

Nice table you have created.
I have run my A119 V3 on two settings.
1920x1080 @60fps bitrate ~ 20Mbs @ 3min videos = ~459MB During the afternoon with good light @ 80kph you can read the Green signs but still some blurring. Can read stationary cars number plates sharp doing step motion on the video. Have some trouble with playback. It jerks the video using VLC player. Using MPC - HC player its fine. Interestingly using stepping the video steps forward every second press of the next frame stepping. Makes me wonder if it is true 60fps
2560x1600 @30fps bitrate ~ 26Mbs @ 3min Videos = ~577MB pulls in lots of light under street lights but a bit grainy and at 60kph can't read large signs Green with reflective white writing type. (Its blurred text) so are the speed signs but legible due to their larger size. During the day doing a still frame you can read the street signs without blur and the image is very good. Can read number plates going in the same direction at 90kph about 2 car length in front.
The quality of the A119V3 at high res is fantastic. Leaves the A129 Duo for dead. Unfortunately the duo has three features I love. 1. Mounting system to the gps is solid. 2. It has a rear camera. 3. can use wifi to set it and to download files... but it is sloowwww.

I haven't enable WDR.
I prefer to set the bitrate at its highest to get the best image. I was hoping setting the dash cam at 60fps would give me better stepping (what you referred to as slow motion) so I could read number plates but it doesn't seem to work that way.
On country roads or if you have a car with stiff suspension you may find the video will shake which spoils the recording. I'm not a fan of the old A119 V1 and V2 (improved but still can shake) type of gps fitting which is also fitted to the A119V3.

Would love a A129 Pro but Viofo are no longer an excellent low price dash cam according to my wallet

 

[Kremmen]

Robert

Use the 1440 setting, second one down, as that's the native resolution of the lens and has the correct aspect ratio for most monitors.

I've experimented with 1080 but it doesn't look as crisp, even at 60fps.

 

[Privateer]

Hi LateralNW and Kremmen,

Nice table you have created.

Thanks. As you've mentioned 60fps I'll add some more data for 1920x1080 and 2560x1440 at 60fps at High, Medium, and Low bitrates.

Talking of bitrates, a few years ago, RoadHawk specified the actual value of the maximum bitrate (i.e. 1, 4, 6, 8, 12, 16, 18, and 20 ) then after one of the firmware updates, they changed the settings to just Low, Standard, High, Very High. I use Very High.

I realised that the above table should show the actual bitrate so I've used QuickTime Player to give me indicated bitrates for the Viofo A119 V3. After getting the data I did the same for the RoadHawk and found that the bitrate was much lower than I was expecting so I checked a few more videos and found that the bitrate was different for each one, i.e. in a range between 12.19 to 16.32 Mbits/s for 1920x1080 at 30fps (actually 29.97fps) for videos tested so far, which shows that RoadHawk uses variable bitrates, and therefore migh help to explain the difference in file sizes of 105 MB and 126 MB per minute at 1920x1080 at 30fps.

Does anybody know if the Viofo A119 V3 has static or variable bitrates for Low, Medium, and High? The readings from the RoadHawk were from in-vehicle whilst the readings from the Viofo were done at my desk and pointing at the same stationary wall. I won't be able to check bitrate variance until I fit the Viofo to my vehicle.

Use the 1440 setting, second one down, as that's the native resolution of the lens and has the correct aspect ratio for most monitors.

Thanks, the 2560x1440 image is one of the things that made the Viofo interesting.

I've experimented with 1080 but it doesn't look as crisp, even at 60fps.

That's weird, I would have thought that 1080 would have been OK.

I was also thinking that running at 60fps instead of 30fps would have doubled the file size but I'm not so sure until I do further testing and update the above table.

Regards,

 

[Privateer]

Hi LateralNW,

I've updated the table to include the actual bitrate for Low, Medium, and High. I've obtained the bitrate value from QuickTime Player.

1920x1080 @60fps bitrate ~ 20Mbs @ 3min videos = ~459MB During the afternoon with good light @ 80kph you can read the Green signs but still some blurring... Makes me wonder if it is true 60fps

I think that I'm correct that you can't get 60fps on 2560x1440. You can only get 60fps on 1920x1080 or 1280x720.

If you look at my table for 1920x1080 for 30 fps versus 60 fps I would expect the file size to be double and they are not. In fact, 1920x1080 Low Bitrate (16.48 Mbit/s) has the same filesize for 30 fps as 60 fps.

Caveat: I'm relatively sure that my table calculations are correct, hower I'm happy for others to let me know if I've got my calculations wrong.

Regards,

 

[Nigel]

I would expect the file size to be double and they are not.

It doesn't need to be double, the amount of movement in the image is the same, just needs a little extra temporal information to cover the cases where things change speed or become visible between the 30fps frames.