How important is license plate capture?

I have one in my car, and even though I live in UK with big number plates, I would definitely choose the A129 Pro over the others. For USA use I would get the A119 V3 over the A129 Duo, although then I would need a rear camera as well - any old cam will do for that! For UK/Europe, the A129 Duo has sufficient resolution and does have the least motion blur so is a good choice.

If all else is equal, surely the A129 Pro would equal or outperform the A119 V3, wouldn't it? There is a suggestion that a 4k sensor necessarily performs worse in the dark than a 1440p one due to having small pixels, but this is a fallacy. The 4k footage will have more noise at the same sensitivity, but it also has more pixels, so it equals out in terms of resolving power.

Also, motion blur is a function of shutter speed. Is this something that can be adjusted with custom firmware? For the purpose of identifying license plates, it is much more important to have sharper still frames, even if it means darker and noisier footage.
 
There is a suggestion that a 4k sensor necessarily performs worse in the dark than a 1440p one due to having small pixels, but this is a fallacy.
Not a complete fallacy, you can't get away from the fact that the pixel walls take up space that can't collect light, and a 4K sensor is going to have twice as much pixel wall as a 1080 sensor.

More importantly, the A119 V3 has one of the latest and best Sony sensors, Sony don't have a 4K equivalent on sale yet, the IMX415 has just appeared with samples for developers, so it will be another year before we can expect a 4K camera with the same sensitivity as the A119 V3, so until the A129 Pro V2, the A129 Pro will only beat the A119 V3 in bright sunshine or when driving in a straight line, turn a corner and create extra motion blur and the A119 V3 wins. I would still choose the A129 Pro over the V3 though, and if I did a lot of night driving then maybe get a standard A129 as well, since the A129 Duo beats the A119 V3 on motion blur.

I've not seen a custom firmware adjust shutter speed, but you can try adjusting the EV setting to a darker setting which should give more shutter speed, however if you adjust it enough to make a significant difference then you end up with a very dark image!
 
The limitation probably isn't the sensor or the resolution, it's the image processing.

Phone cameras use heavy processing, what they call computational photography. That way they get great HDR and great clarity out of tiny sensors and very limited lenses. By comparison the processing in any dashcam I've ever seen is extremely primitive.
 
well i have been waiting for someone using phone hardware, maybe for a larger multi channel system.
But for a single dashcam i cant see that being a option as i think that will be too expensive.
Also like my new phone do bundle 3 of its pixels up to one to do better in low light, i am not even sure that are supported in the hardware used to make current dashcams.
but taking a 48 mpix sensor and that way turn it into a 12 mpix sensor, well that work great for low light performance.
 
Dashcams could be better, but the cost would render them unmarketable. They're not meant to be the best possible cameras, just good enough to help you protect your car. There's already a huge thread here on this so there's no point in beating it again.

Compare dashcams against other dashcams based on whatever criteria you prefer, then select the one you want. If you can't get what you want then look elsewhere and see if you can find a satisfactory substitute. We will get better dashcams when they hit the market, whenever that happens to happen, and not one moment sooner.

Phil
 
well i have been waiting for someone using phone hardware, maybe for a larger multi channel system.
But for a single dashcam i cant see that being a option as i think that will be too expensive.

I dunno, some of these dashcams cost more than mid range phones and have worse cameras. How is that a thing?
 
Indeed.
Though Dashcams don't see the same sales numbers as phones, i am sure if the turn over was much larger the companies could also put more money into R&D.
You can also now get new phones that are pretty crappy at least for most western phone users taste, and you can get phones that cost a lot more than some phone users would ever pay.
I have just set a personal record paying a little over 400 USD for a phone that truth be told have 80 % more performance than i need,,,,, so once again i over killed on hardware.
So right now saying i really hate smartphones,,,,, is a little more hard to do if people knew what i have just done, i am also pretty confused myself,,, maybe i am a closet phone lover.

Yes you can use some cheap or old Mediatek or Qualcom SOC and build a camera on that, but i am not sure it would be able to do all the Uber stuff some people would like in a dashcam.

At one time i was also saying, well camera sensors speak some well defined language, so why don't people use more exotic sensors that could make for better dashcams.
But i was told its not as simple as that, and i think its the same for sensor support in phone cameras, at least when you look at the market it seem like phones tend to often use the same few sensors.
 
The limitation probably isn't the sensor or the resolution, it's the image processing.

Phone cameras use heavy processing, what they call computational photography. That way they get great HDR and great clarity out of tiny sensors and very limited lenses. By comparison the processing in any dashcam I've ever seen is extremely primitive.
Computational photography is great for photographs where you can take a couple of seconds taking different exposures from different lenses and then combining the results over another second or two to get a single frame, but for video at 30 fps...

I've never heard of computational videography... but google has...
 
Computational photography is great for photographs where you can take a couple of seconds taking different exposures from different lenses and then combining the results over another second or two to get a single frame, but for video at 30 fps...

Well, the video on my Pixel is excellent... No optical stabilization, it's all done computationally. Hand held shots from inside a car look like a steadycam.

One other thing the phone can do is take photos while recording video. If you tap the screen during recording it takes a full quality photo and keeps recording the video. One high quality photo per second, or maybe combined with some licence plate recognition would be great. Or even just 3 fps video consisting of high quality frames.

I'd much rather have clear number plates and low frame rate than high frame rate and everything is illegible.
 
Are you sure the Pixel has no mechanical stabilisation? Which model?

On most dashcams, the video is at full sensor resolution, so taking a photo does not help, unless maybe it was a raw or 12 bit photo, but that would be too slow and wouldn't make much difference.

I'd much rather have clear number plates and low frame rate than high frame rate and everything is illegible.
Yes, 30fps is more frames than necessary, but it looks much better when you watch it than slower frame rates!

However slower frame rates won't help in the dark since taking longer would create too much motion blur, and in daylight they are unnecessary.

Suggest you try using your Pixel mounted on your dashboard to record some night time dashcam video, I suspect the result will be nowhere near as good as you expect...
 
Indeed and i just said that a week or 2 ago some other place in here.
I will take a 15 FPS camera if those 15 FPS can give me detail like plates all day.
Though i don't think i would run that camera alone, but thats just me

Some cameras can also take a stack of pictures with different exposure settings for each photo, and then stack them on top of each other to a single photo with all the good information of the sub photos.

 
Are you sure the Pixel has no mechanical stabilisation? Which model?

On most dashcams, the video is at full sensor resolution, so taking a photo does not help, unless maybe it was a raw or 12 bit photo, but that would be too slow and wouldn't make much difference.

Original Pixel XL. No optical stabilization at all.

And yes, dashcams need better sensors. They aren't expensive, even cheap phones have them now.

However slower frame rates won't help in the dark since taking longer would create too much motion blur, and in daylight they are unnecessary.

The Pixel improved low light performance by having a larger than usual sensor. I suspect that is one reason why dashcams use low resolution sensors - each pixel gets more light, improving low light performance.

With computational photography the benefit is that you can composite several exposures, so at night you don't get the blown out reflective surfaces like number plates.
 
Yes my 48 mpix sensor bin 4 into 1 and become a 12 mpix sensor for low light operation, but i am not sure current hardware SOC used in dashcams support pixel binning, or if it make sense with binning a lot smaller pixels instead of having lesser but larger pixels like in the starvis sensors used at the moment in dashcams.

My phone take 4 0.8 µm pixels and bin those into one 1.6 µm pixel and so go from 48 mpix to 12 mpix,,,,,, thats still smaller than say the 5 mpix IMX 335 that have 2 µm pixels, and the popular IMX 291 have 2.9 µm pixels.
One of my CCTV cameras have 3.75 µm pixels. ( 1080p )

I do think all professional low light cameras, use huge sensors with just the right number of huge pixels.

i would take a full frame 35 mm sensor in 1080p resolution, that would be a beast light trap, but it would also need a pretty expensive lens and it would all make up for a huge dashcam.
 
Last edited:
I would still choose the A129 Pro over the V3 though, and if I did a lot of night driving then maybe get a standard A129 as well, since the A129 Duo beats the A119 V3 on motion blur.

I guess I will wait for the A129 Pro video samples before making a decision between it and the A119 V3. If you had to add a rear camera to the A119 V3, what would be the best way to do it? Would it require two separate hardware kits?

Dashcams could be better, but the cost would render them unmarketable. They're not meant to be the best possible cameras, just good enough to help you protect your car. There's already a huge thread here on this so there's no point in beating it again.

I haven't come across the thread that you are referencing, but I completely agree. In addition to cost, dashcams have size, power consumption and processing power limitations, and it is simply not possible to put a power hungry SoC that you would find in a flagship smartphone in a dashcam package. You can take it further and mount a Sony A7III to your windshield and get amazing video quality day and night, but it is obviously that this is not a practical solution.

With computational photography the benefit is that you can composite several exposures, so at night you don't get the blown out reflective surfaces like number plates.

Can't do that with a moving image, and is also not practical with the computation power available in a dashcam.

i would take a full frame 35 mm sensor in 1080p resolution, that would be a beast light trap, but it would also need a pretty expensive lens and it would all make up for a huge dashcam.

Aside from resulting in an impractically large dashcam, a larger sensor won't produce as much of a benefit as you might think. The focal length of the lens is now much longer (~14-15mm for a ~140° FOV), so the aperture needs to be f/5.6 or smaller to retain an acceptable depth of field. You might gain 3 stops of dynamic range with a large sensor, but then need to give 2 stops back for the depth of field.
 
Last edited:
I guess I will wait for the A129 Pro video samples before making a decision between it and the A119 V3. If you had to add a rear camera to the A119 V3, what would be the best way to do it? Would it require two separate hardware kits?
Rear camera can be of lower specification, something small and cheap like the Blueskysea B1W is adequate for most people. Not sure what I'd recommend for a high quality rear camera at the moment, cameras like the A119 can be used on the rear but they are a bit big and visible. Gitup F1 might be a stealthy option, or one of the Mobius cameras.

Bit difficult to use a standard hardwire kit for two cameras, although they do provide enough power, so yes, two, or plug the rear camera into the accessory socket in your boot if you have one or can fit one. Personally I use an Orico 12 volt 4 port USB charger, which hasn't been enough for the last week with 8 lenses in the car! Works well, but doesn't have low voltage cut off for parking mode.
 
Bit difficult to use a standard hardwire kit for two cameras, although they do provide enough power, so yes, two, or plug the rear camera into the accessory socket in your boot if you have one or can fit one.

I have a 12V socket in the back, so I can use that for power if it came to that. Thank you for your input!
 
I dunno, some of these dashcams cost more than mid range phones and have worse cameras. How is that a thing

Some dashcams are hugely over-priced, selling mostly on hype and features instead of good video. Phones get to spread development and build costs over many million units, while dashcams have to do that over just several thousand units. Thus it's going to cost more here than there to get the same thing. Economics 101 ;)

Phil
 
I dunno, some of these dashcams cost more than mid range phones and have worse cameras. How is that a thing?
average mid spec phone, 1.5Ghz octa-core processor

average dashcam, 700Mhz single core ~ 400Mhz dual core processor

put any phone in your window and run it 24/7 as a dashcam and it will die, how is that a thing?

different product, different task
 
put any phone in your window and run it 24/7 as a dashcam and it will die, how is that a thing?

Nonsense. Bjorn uses multiple phones to stream his longer journeys. 16+ hours in a stretch, with the video being streamed live to YouTube. He's done it on trips to southern Europe where it gets pretty hot.

Also phones are a lot thinner than dashcams because they need to fit in the hand. If you have more flexibility with the shape you can have significantly better cooling.
 
Back
Top