New Viofo A139 !

[Nigel]

It would be helpful if there was a true reference as to how these differ - HDR vs WDR in viofo cameras

Like I said before, HDR helps with the overexposed areas and WDR helps with the underexposed areas.

Both result in a loss of contrast and a less impressive image, so for movie making you would probably want to turn them off, for evidence gathering you want them on. Although on several recent Viofo cameras we have been recommending leaving WDR off since it can make a bit of a mess of the dark areas which are actually quite good even with it off.

Completely different use of the term HDR than when used for monitors.

 

[Mtrev]

Had problems with a previous model where it interfered with the DAB radio and car remote, does anyone know if this model is any better ?
Thanks

I have the rear coax running on my boot lid with some of the aerial cables and past the antenna diversity amp with the camera attached to the top of the rear screen and I haven’t noticed any dab issues. There is actually an exact point where I know a particular dab ensemble drops out and this hasn’t changed since adding the camera so I suspect it is unaffected.

 

[runtohell121]

I'll vote for HDR also for the rear cam if it doesn't effect any performance of the dash cam. Or make it optional for the user to choose.

 

[viofo]

The final retail version will optimize heating radiating, this will also help to receive GPS signal.

 

[kamkar]

While i would recommend a person to get a dual channel camera, and i am myself a user of rear camera, then the rear one are not of that much interest to me as it is very rare i pull footage of that camera.
But of course any camera in a system i would like to be as good as technically possible, but if i had to choose i would prefer that the focus are 100% on the front camera at least as long as it is not as good as it will ever be.

Buyt lets say planning a new camera and you have a set budget, i would rather have a better new front sensor and then a lesser one in the back, than in any way spreading the money out onto 2 other sensors, maybe the same in both ends of the car.

 

[runtohell121]

Where can I find the latest firmware? I received my unit yesterday, installed it tonight.

 

[Jeremy Wong]

Where can I find the latest firmware? I received my unit yesterday, installed it tonight.

PM Viofo for it [emoji4]

Sent from my SM-G988B using Tapatalk

 

[joe384]

Like I said before, HDR helps with the overexposed areas and WDR helps with the underexposed areas.

The technical definition of HDR and WDR are both the same according to wikipedia!

Both result in a loss of contrast and a less impressive image, so for movie making you would probably want to turn them off, for evidence gathering you want them on. Although on several recent Viofo cameras we have been recommending leaving WDR off since it can make a bit of a mess of the dark areas which are actually quite good even with it off.

Completely different use of the term HDR than when used for monitors.

As I mentioned above the terms are irrelevant as even wikipedia says they are the same, so we have to throw the terms out the window and ask what are the exact hardware and software processes going on for each "definition". A manufacturer could easily swap your definitions around and they would be correct.

 

[joe384]

Just a few examples:

Video Blog: High Dynamic Range (HDR) vs Wide Dynamic Range (WDR) - March Networks

Watch as we compare the High Dynamic Range (HDR) in one of March Networks' Outdoor IR Dome cameras to a standard camera's Wide Dynamic Range (WDR).

www.marchnetworks.com

This article is titled HDR vs WDR but is just an advert for their HDR technology. Near the end it says:

"While the definition of WDR varies from manufacturer to manufacturer, generally, it refers to a camera’s ability to produce high-quality images across a wide range of light levels. March Networks’ cameras with digital WDR use advanced algorithms to lighten or darken a single exposure."

Lots of articles mentioning WDR saying WDR helps with both light and dark images:

Wide Dynamic Range - WDR | Axis Communications

Forensic WDR is our latest and most advanced WDR technology. Employing the latest generation of image processing algorithms, this technology effectively reduces visible noise and artifacts to deliver video tuned for maximal forensic usability.

www.axis.com

Wide Dynamic Range (WDR) | VideoSurveillance.com

Security Cameras with Wide Dynamic Range (WDR) make it easy to balance light for clear surveillance video.

www.videosurveillance.com

Surveillance | i-PRO Products

In order to help create a safer and more peaceful world, i-PRO supports the work of professionals who protect and save lives.

security.panasonic.com

 

[Nigel]

Lots of articles mentioning WDR saying WDR helps with both light and dark images:

Not in any of the dashcams using Novatek processors, which is most of the current decent ones!

A manufacturer could easily swap your definitions around and they would be correct.

The sensor manufacturers often do, however when talking about dashcams, WDR is almost always single exposure and HDR almost always multiple exposure. You will not get an exact definition because the manufacturers are not consistent in their use of the terms. The only consistent thing you can say is that they are both supposed to record a larger range of light levels than a normal photo/video camera would.

 

[kamkar]

In CCTV cameras you also have BLC ( back light compensation ) HLC ( high light compensation )
TBH these aspects of CCTV are also not something i have geeked out on much.

This video also explain a bit about merging pictures ( bracketing ) on my action camera.

 

[joe384]

Not in any of the dashcams using Novatek processors, which is most of the current decent ones!


The sensor manufacturers often do, however when talking about dashcams, WDR is almost always single exposure and HDR almost always multiple exposure. You will not get an exact definition because the manufacturers are not consistent in their use of the terms. The only consistent thing you can say is that they are both supposed to record a larger range of light levels than a normal photo/video camera would.

Thanks, that makes sense now, I did a search on "wdr single exposure" and it brought back quite a few papers that go into detail and also the methods that some companies use to increase the dynamic range.
I think I will stick to WDR off in my a139 test unit until the HDR option becomes available to test.

 

[SawMaster]

WDR and HDR are things one should test for themselves, perhaps through the seasons, as normal lighting conditions day and night vary by latitude and location, and there's also considerable difference between those driving only in cities with street lighting, and those in rural or less-well-lit locations. Use of a CPL can also have an effect here

There's more to it than just the cam.

Phil

 

[kamkar]

The image adjustments ( also to WDR ) that soon roll out to SG cameras look to be very fine indeed.
And best thing is i think all of that are as a result of working with modders, and why wouldn't you enlist so dedicated people they try and make things better all on their own.

 

[Nigel]

And best thing is i think all of that are as a result of working with modders,

Doesn't that prove that the professional experts are not very good at their jobs?

 

[kamkar]

Or cant get permission to do the job properly, for that reason i have had to quit several jobs as my mind can not handle making a poor quality work.
Every time also followed with a application to work at the only air and space employer in the area ( Terma ) as i know they make the good stuff / highers standards as only that will do in those areas.

 

[vvs49]

The VIOFO application for wifi does not work for me on the auto GU there is android 4.4
I connect 139, the program opens and immediately closes, on smart android 5 everything is OK
The A129 Duo worked great on this car.
With another application RitmixCam, it works without problems.
I don't like the interface there.
There was one more, worked great, but I lost the name !!
Who uses which?

 

[SawMaster]

Doesn't that prove that the professional experts are not very good at their jobs?

Not necessarily. Professionals must justify their positions as well as make for a better situation for whoever they are working for. They are usually constrained to working within the existing structure, and withing limited timeframes too. Hobbyists have no such considerations and often have more zeal to achieve what they want more perfectly. There are more of them so more approaches and variations can be pursued. They have more varied locations and situations than the 'Pros' do. Plus their 'services' are free which keeps products more affordable.

Wherever the input comes from, if it makes for better results then you might as well make good use of it

Phil

 

[Mtz]

BTW, do you think HDR for the rear cam is important or necessary?

I think it is, because most of the time there will be a car which shines its headlights and blinds the rear unit.

They do two different things, but simplifying things too much, WDR helps with the dark areas and HDR helps with the bright areas. I would expect an HDR setting to actually do both, so it will be better if/when it works well.

So maybe for rear camera is better WDR compared to HDR.

I think this is quite useful state already.

That video comparison for HDR is not correct, it is very wrong. Such comparisons should be made only using 2 cameras at the same time, perfect aligned. Usually that guys are doing a good job but this comparison is poor.
Also they have some video comparison with 2 cameras where they are choosing for example frame number 12345 where HDR is better, but on frame 12356 the HDR = Off frame is better, so in their side by side comparison the HDR was not always better. The problem is not that the HDR is not working like we want, the problem is the users to be correct informed and because of this a forum is better than a Youtube channel or some blog.

enjoy,
Mtz

 

[Nigel]

So maybe for rear camera is better WDR compared to HDR.

If you are trying to read the plate on the car behind then yes, it is WDR you want, if the headlights are over exposed it does not matter. The plate is hard to see at night because it is lit only by your tail lights, and with most cameras the plate is hard to read unless you also put your brake lights on.

However if you are trying to read the plates on passing cars then the HDR is likely to be useful because HDR reduces motion blur on brighter objects. A good HDR would be worth having on the rear camera, especially if it works well in daylight.

It is the front camera where we really want HDR because at the front in darkness, plates are often overexposed by our headlights. Also in brighter lighting, good HDR may be able to reduce motion blur in the brighter areas without causing underexposure in the dark areas. That might be asking too much of a dashcam though...