Do any dash cams take pictures along with taking video?

[eamike261]

Identifying a license plate is a critical requirement. Therefore, I'm curious if any dashcams focus on doing a good job of that by taking pictures every X seconds to match up with video. Considering that single image quality in a video is often really crappy (try pausing a video on your iphone compared to taking a picture on your iphone) I'm wondering if a few snaps would greatly enhance the ability to identify a car if the license is blurry in a video?

 

[kamkar]

Not really.

The B1W do take a single picture at the start of every segment, but there are no cameras that take a picture every second or so ( though it have to be more of than that that for a car and the fast paced environment they move thru )
you are right that if you pause a video or go thru a video footage frame by frame you will notice poor IQ you dident really notice at playback, this are mostly to do with the way our eyes work, and out brain extrapolating on what it assume things must be / look like.

But even if you are snapping individual photos and not video frames, the problem will be the same, and in general this are down to the exposure timing the camera choose to use, and if there are little light then the camera drop / slow down exposure so the sensor have time to collect more light. and this are also fine IF ! there are no movement ( which there always are in dashcam footage )

The best low light performing dashcams use the Sony MIX 291 sensor today, but thats still just a 2.1 megapixel sensor with just enough pixels to capture a 1920 x 1080 image, and the reason for that is the individual pixels on the sensor are large and so better at capturing light.
you can have another sensor with the same physical size but then have 20 megapixel, but to make room for all those pixels on the sensor they have to be much smaller and so worse than capturing light.

Now you can get sensors that can capture stunning low light footage too, but then we are talking about full frame sensors or larger where you have room for the large individual pixels and still have them large and light sensitive.
And then we are talking a whole other ballgame when it come to price, you will probably have to put at least 2 more zeros on the price tag for a camera with that kind of hardware.

With the technology in todays dashcams you can really only expect plate capture ( even of large simple EU plates ) in the best of weather in the daytime, it dont even have to be late evening for dashcams to start struggling with illusive things like plates on cars.

There are tricks like pixle binning on some cameras, this mean the camer bin 4 pixels on the sensor to act as one and so more light sensitive unit, but doing that you of course sacrifice resolution.
This we have not yet seen in dashcams, but i recon we will see that soon, and personally i dont think its all that stupid.
Say you have a sweet sensor with the +8 megapixel it takes to record nice daytime 4K footage, when the light then dim the camera could change to binning and so just have 1/4 of the resolution but then be much more light sensitive.

BUT ! you should not focus that much / hard on plate capture, if you do you will never get a dashcam, of pay over the moon for something professional thats not really a dashcam.
And trust me any dashcam are much better than no dashcam.

 

[Nigel]

Identifying a license plate is a critical requirement. Therefore, I'm curious if any dashcams focus on doing a good job of that by taking pictures every X seconds to match up with video. Considering that single image quality in a video is often really crappy (try pausing a video on your iphone compared to taking a picture on your iphone) I'm wondering if a few snaps would greatly enhance the ability to identify a car if the license is blurry in a video?

The good dashcams have 1080 resolution sensors and they record 1080 resolution video, so taking a photo doesn't give any extra resolution. The only advantage would be if the photo had less compression, however that is not normally the case, as long as the video bitrate is decent then the photos don't have any advantage over a freeze frame from the video.

It may be possible to get a better photo if you used a lower ISO setting and longer shutter speed, but you can't do that because the sensor is in use for video, and anyway it would cause extra motion blur which is normally bad for reading plates.

 

[SawMaster]

If plate capture is important, the best sensor for that is your eyes. One trick some people do is say the plate number aloud so the cam's audio recorder remembers it, and it is time-referenced to that spot in the video. Between those two you should have enough to get official involvement of some kind if you need it.

Phil

 

[TonyM]

There are some action cameras that are also used as dashcams which can record video along with photos at regular intervals. The 8MP / 4k GitUp F1 can do it, for example. However I consider the time interval between photo frames is too big to be really useful for number plate capture.

 

[TonyM]

If plate capture is important, the best sensor for that is your eyes. One trick some people do is say the plate number aloud so the cam's audio recorder remembers it, and it is time-referenced to that spot in the video. Between those two you should have enough to get official involvement of some kind if you need it.

Phil

That's good for cars in front of you that you can see. Not so good for ones that rear end you!

 

[eamike261]

Not really.

The B1W do take a single picture at the start of every segment, but there are no cameras that take a picture every second or so ( though it have to be more of than that that for a car and the fast paced environment they move thru )
you are right that if you pause a video or go thru a video footage frame by frame you will notice poor IQ you dident really notice at playback, this are mostly to do with the way our eyes work, and out brain extrapolating on what it assume things must be / look like.

But even if you are snapping individual photos and not video frames, the problem will be the same, and in general this are down to the exposure timing the camera choose to use, and if there are little light then the camera drop / slow down exposure so the sensor have time to collect more light. and this are also fine IF ! there are no movement ( which there always are in dashcam footage )

The best low light performing dashcams use the Sony MIX 291 sensor today, but thats still just a 2.1 megapixel sensor with just enough pixels to capture a 1920 x 1080 image, and the reason for that is the individual pixels on the sensor are large and so better at capturing light.
you can have another sensor with the same physical size but then have 20 megapixel, but to make room for all those pixels on the sensor they have to be much smaller and so worse than capturing light.

Now you can get sensors that can capture stunning low light footage too, but then we are talking about full frame sensors or larger where you have room for the large individual pixels and still have them large and light sensitive.
And then we are talking a whole other ballgame when it come to price, you will probably have to put at least 2 more zeros on the price tag for a camera with that kind of hardware.

With the technology in todays dashcams you can really only expect plate capture ( even of large simple EU plates ) in the best of weather in the daytime, it dont even have to be late evening for dashcams to start struggling with illusive things like plates on cars.

There are tricks like pixle binning on some cameras, this mean the camer bin 4 pixels on the sensor to act as one and so more light sensitive unit, but doing that you of course sacrifice resolution.
This we have not yet seen in dashcams, but i recon we will see that soon, and personally i dont think its all that stupid.
Say you have a sweet sensor with the +8 megapixel it takes to record nice daytime 4K footage, when the light then dim the camera could change to binning and so just have 1/4 of the resolution but then be much more light sensitive.

BUT ! you should not focus that much / hard on plate capture, if you do you will never get a dashcam, of pay over the moon for something professional thats not really a dashcam.
And trust me any dashcam are much better than no dashcam.

If plate capture is important, the best sensor for that is your eyes. One trick some people do is say the plate number aloud so the cam's audio recorder remembers it, and it is time-referenced to that spot in the video. Between those two you should have enough to get official involvement of some kind if you need it.

Phil

Thanks for the really informative response! That helps my understanding a lot. I guess I'm stuck in a bit of a hard spot though. I am particularly interested in the hit and run cases where I was not present in my vehicle when it happened so saying the plate out loud won't be an option but I guess having a dash cams to at least capture daytime hit and runs is better than nothing at all. Thanks again for the replies!

 

[kamkar]

Yeah it is what it is, sadly there dont seem to be any quantum leaps in the future when it come to image quality.
Calling out a plate t night time are a good option, but maybe i am going blind cuz i have tried to just make out the plates of cars at night, and it is not often i can get the 2 letters and 5 numbers on EU plates.
And out plates are very easy to read / capture Vs the US plates that in general seem to be made with anything but readability in mind.
Hit and run are of course bad, and it is also on the up here in Denmark as our society continue its cultural decline, but it is still not something i have experienced myself so i am pretty relaxed about it.
On the other hand out right vandalism, that i have never tried before i sold my house and moved to this town, then it happened 3 times in a short period.
First i had my Suzuki SUV keyed along one side, days before i was to sell it
I then got my current little Suzuki 5 door hatchback, and within 2 months it had the front passenger side door glass broken, but door was not opened and nothing missing from car.
And then a bit later some one appear to have thrown a D cell battery far into the air, and it then landed on my roof making a dent there.
So now i park in the back yard and i have a CCTV camera on my car where it is parked, and if some one again mess with my car, i will go judge and jury on them and i will not be as weak as the Danish justice system are in general.

Night time you pretty much will just be able to get make/model and color of a vehicle, this also go some way i am sure, depending on how you live / park there is a good chance that the culprit will pass by often, so you know what to look out for.

 

[SawMaster]

That's good for cars in front of you that you can see. Not so good for ones that rear end you!

If they back away afterward you can see their front plate in your mirrors. If they turn around or pass you, you can see the rear plate. If it's at night you jump out and get the plate with your honking big flashlight, which will probably let the rear cam get more details too. And you use enough light, you'll temporarily blind the buggar making it alot harder for them to run

No dashcam is going to cover every possibility. These cams are not professional "Hollywood" stuff where there's a crew working everything and enough time to set things up to get a perfect shot. They generally capture enough to prove your innocence in a crash and to get at least a halfway decent description of a person or car who causes you or your car grief. That is usually enough, and if you're that concerned about it you should get well-insured to cover the rest. You can't really expect more from a ~$200 consumer-grade product. Your eyes will always be able to outperform a dashcam at close range.

Phil

 

[Rajagra]

Some video compression formats do include regular 'complete' images:
https://www.dipolnet.com/h_264_compression_-_learn_and_use_in_practice__bib312.htm

Some video editing packages let you skip forward to the next complete frame, I expect some playback software does too (e.g. VLC?)

Whether the frame quality would match a photograph being taken is another matter, but any camera that attempted to take a photo at the same time as recording video would probably face the same obstacles.

 

[SawMaster]

any camera that attempted to take a photo at the same time as recording video would probably face the same obstacles.

This exactly. The cam settings for a perfect "still" image will not be the settings best for continuous video, so it's impossible to have both together. We just have to live with the compromises involved here and set our cams up to best do what we want them to do at the cost of everything else, knowing that even our best efforts will not give us 100% of what we want.

Some cams like the original Mobius are highly adjustable, but most have very limited adjustability. Some cams are currently being "tweaked" by hobbyists through firmware and lens changes to improve the situation. If you are really obsessed with plate capture then you should research what those goings-on are doing and see which cams, firmwares, and lenses are getting the best plate captures. Then choose among one of those based on what you think, because these "modded" cams are out performing the stock ones, and there is probably better to be found with them in the future too.

Every dashcam is a compromise of some kind, so if you want the best of one thing you may not get much of the rest.
Phil

 

[docesam]

i am sure that a infrared photo-only camera with an IR flash can be done economically (to complement a video dash cam).

 

[Hermes14]

If you need to take a single shot you can use a video editor lie openshot.
If the image is blurred you software to correct it.
Linux you can use ffmpeg & windows you can use something like focus magic

OpenShot Video Editor | Free, Open, and Award-Winning Video Editor for Linux, Mac, and Windows!

OpenShot is an award-winning free and open-source video editor for Linux, Mac, and Windows. Create videos with exciting video effects, titles, audio tracks, and animations.

www.openshot.org

FFmpeg

www.ffmpeg.org

Focus Magic - Sharpen Your Blurry Images and Photos

Focus Magic is software that uses advanced forensic strength deconvolution technology to literally “undo” blur, recovering lost detail from images/photos.

www.focusmagic.com