Dashcam with REAL parking mode

Could you tell me a little more about the complaints (or disadvantages)?

I was looking at the blackvue 750 as well.
I really liked the idea that the parking mode get automatically activated when vehicle doesn't move since I'm thinking about connecting dashcam to powerbank.

Are there other dashcams do similar thing?
Is this a pretty common thing in dash cam with parking mode feature?

the Blackvue are just a 2 wire connection so it relies on the camera to work out when you're parked or moving, this is already making things harder than a 3 wire connection that can know for sure what power state the vehicle is at but they also rely on motion detect for their parking mode which has lots of problems as you'll find it either too sensitive and it runs all the time, or not sensitive enough and misses things, very hard to find the right balance when relying on motion detection
 
it's true for the type of parking mode their cameras do, if you have a camera that goes into a sleep state and only wakes up when the G-Sensor activates and then goes back to sleep after then this needs an internal battery

it's not what most consumers perceive to be parking mode though
Which capacitor dashcam has such parking mode feature?
I've been using 2 Goluk T3 cams and they're great. Been using them for almost a year now and I can tell you the spring mode works excellent. The T3 is capacitor based too so heat isn't a problem and I live in Texas. Haven't had any issues with them. I run a 128gig card in the front and a 32 in the rear. Quality is great as well. When the parking mode kicks in you'll see video motion a few seconds before you see something happen. I love that. I'm using the Anypower T plus Alpha battery back up and it's awesome. Cost much less than the other popular models people always talk about or mention. I paid $350 for both cams and the battery back up and installed everything myself. I have a 2018 Camry XSE but was running this setup in my 2015 Challenger scat pack as well. Here is some sample video as well.





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Hi all,

My wife has a new car.
I would like to install a dashcam with a good parking mode.

Should I buy a Blackvue 750S-2CH right now, or may I expect some chinese dashcams to come this year with a similar buffered parking mode (motion detection + G-sensor).

A 2CH Streetguardian with buffered parking mode would be perfect !

Choose the M02 dash cam with time lapse,no more worrying over files getting overwritten in Parking Mode.
 
Thanks but I don't like timelapse, I would prefer motion detection @30FPS.
 
Chris,

Since this post way back in January, I've been running Blackvue DR590 2ch system. It has the buffered parking mode and it works great. I haven't had any issues thus far. Only small minor hiccup was having to adjust the default motion detection from "2" down to "1" as it was too sensitive. I have the non wifi model. I keep an OTG to USB adapter in the car and can download the video files directly to my phone. It's much faster than wifi.
Thanks but I don't like timelapse, I would prefer motion detection @30FPS.

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Thanks @Nowuseeme , I have installed a Blackvue DR750S-2CH in the car of my wife and works fine.

But I'm still interested with future chinese dashcam buffered parking mode;)
 
Thanks but I don't like timelapse, I would prefer motion detection @30FPS.
M02 dash cam with motion detection is enabled, when the vehicle recorder detects the movement of the object, the camera starts recording, and the camera automatically enters the motion detection standby state after the motion detection is finished. When the object is detected again, the camera function is started again.
 
I said BUFFERED parking mode.
All other motion detection is useless because recording some seconds after movement.
 
timelapse saves space, dropping the framerate of video doesn't, it's not just about space though, there are still other concerns

One would think halving the number of frames would halve the file size too, but going by your response there seems to be more to it.
Yes, depending on compression method you'll end up with somewhere around half the size (the higher framerate video could compress better). And no matter what compression you're using you're absolutely going to get a smaller file - you've got half the raw data to deal with.

I don't understand that claim at all, time-lapse is essentially really low frame rate.
 
lowering the bitrate reduces the file size, lowering the frame rate of video does not

timelapse is not the same as low frame rate video, it's a different process
 
lowering the bitrate reduces the file size, lowering the frame rate of video does not

timelapse is not the same as low frame rate video, it's a different process
But why would you lower the framerate and not lower the bitrate? You're dealing with half the amount of raw data, so it's a given you don't need the same bitrate.
Think about it: you've got a 30fps video and you save it at 12mbit/s, that gives you 0.4mbit's per frame. Then take a 15fps video and record it at 6mbit/s and you've still got 0.4mbit's per frame. Granted you will see some variance - either in quality with a fixed bitrate or size if it's variable - due to things like interframe compression.

It depends how you save the timelapse - if you save it as jpegs then sure, it's a series of images - if you save it as a video (i.e. H264 in mp4, which I'd kind of expect from the chipsets in these cameras) it is a low bitrate video.
 
But why would you lower the framerate and not lower the bitrate? You're dealing with half the amount of raw data, so it's a given you don't need the same bitrate.
Think about it: you've got a 30fps video and you save it at 12mbit/s, that gives you 0.4mbit's per frame. Then take a 15fps video and record it at 6mbit/s and you've still got 0.4mbit's per frame. Granted you will see some variance - either in quality with a fixed bitrate or size if it's variable - due to things like interframe compression.
If you are parked in a car park then very likely the image is not changing most of the time, the number of bits per second required to store the changes between frames for 1fps is the same as the number required for 1000fps, because there are no changes to record. Reducing the bitrate will reduce the file sizes because most dashcams work at fixed bitate, or close to fixed bitrate, reducing the framerate will make no difference to file size or image quality.
 
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timelapse is not like normal video, if you take normal video and drop it down to 5fps but leave the bitrate the same as what you do for 30fps video the files are still the same size, there are cameras in the market that offer this function and you can test it yourself to see, if it's just normal video you can drop the bitrate to save space, if you're only doing it while parked you can get away with the lower bitrate as you're not moving
 
If you are parked in a car park then very likely the image is not changing most of the time, the number of bits per second required to store the changes between frames for 1fps is the same as the number required for 1000fps, because there are no changes to record. Reducing the bitrate will reduce the file sizes because most dashcams work at fixed bitate, or close to fixed bitrate, reducing the framerate will make no difference to file size.
Ok my first post assumed a non fixed bitrate. Of course reducing the framerate and keeping the same fixed bitrate won't decrease the filesize - but it reduces the amount of data going into the encoder which in turn allows you to reduce the bitrate while keeping the same quality, which reduces the size of the file.
Yes a still image from a parked car is going to compress well - but there is still going to be changes, even if it's perfectly still you'll get noise from the sensor, changes in light, etc. Plus the encoder is going to enforce keyframes so the bitrate required to sustain quality will increase with framerate - just at a slower rate than video with a lot of movement.
 
you can get away with using a lower bitrate since you're static and it's only the scene that is changing, if you look at 5mbit parking video it's pretty acceptable, if you look at 5mbit driving video it quickly becomes a pixelated mess with no usable detail
 
you can get away with using a lower bitrate since you're static and it's only the scene that is changing, if you look at 5mbit parking video it's pretty acceptable, if you look at 5mbit driving video it quickly becomes a pixelated mess with no usable detail
But we're not talking about 5mbit parking video vs 5mbit driving video. We're talking about 5mbit 15fps video vs 10mbit 30fps video.
 
But we're not talking about 5mbit parking video vs 5mbit driving video. We're talking about 5mbit 15fps video vs 10mbit 30fps video.

there's no real benefit to dropping the frame rate for normal video, just drop the bitrate when parked will be fine, this is not timelapse video, that is different
 
Ok my first post assumed a non fixed bitrate. Of course reducing the framerate and keeping the same fixed bitrate won't decrease the filesize - but it reduces the amount of data going into the encoder which in turn allows you to reduce the bitrate while keeping the same quality, which reduces the size of the file.
Yes a still image from a parked car is going to compress well - but there is still going to be changes, even if it's perfectly still you'll get noise from the sensor, changes in light, etc. Plus the encoder is going to enforce keyframes so the bitrate required to sustain quality will increase with framerate - just at a slower rate than video with a lot of movement.
The important bit is, what bitrate do you need to record the bit of video when someone drives into your car, and because there will be a lot of movement at that time you need a high bitrate. The amount of change between frames for 15fps is maybe twice the amount of change for 30fps, so you maybe need twice the bits per frame for the 15fps case, which is the same number of bits per second - changing frame rate doesn't make much difference to the bitrate requirement unless you are recording at 1000fps.

Unfortunately our current video encoders don't seem to be capable of variable bitrate that works well, so nearly all dashcams are either fixed, or variable but limit the range to a fairly narrow window.

A good video encoder will remove the sensor noise. Key frames are not required frequently, I archive video with 1 minute key frame intervals (30fps x 60seconds = 1 in every 1800 frames).
 
there's no real benefit to dropping the frame rate for normal video, just drop the bitrate when parked will be fine, this is not timelapse video, that is different
Typically, if you don't reduce the frame rate for low bitrate video then the encoder will do it for you, but if it can then it only reduces frame rate for the relatively unimportant parts of the image such as the sky and road surface while maintaining a high frame rate for the more significant parts, if there is very little changing then all parts will maintain a high frame rate - a much better result than reducing the frame rate yourself - it is the bitrate that is the important figure.
 
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there's no real benefit to dropping the frame rate for normal video, just drop the bitrate when parked will be fine, this is not timelapse video, that is different
Try going from working with 24fps to 120fps and say there's no difference. There's a big difference, it's not going to be a completely linear relationship because there's a lot of factors, but higher framerate means more data. Sure the control over filesize is with the bitrate, but that also controls the quality, and framerate is rather a large variable for quality.
I'm coming from an entirely different area of video though and maybe these encoders just can't deal with things the way I expect.
 
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