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We recently got a dash cam setup with front and rear cameras. These record in five minute segments, amounting to about 700 Kb for the front and 400 Kb for the back, per minute of driving time. At this rate an hour's driving time works out to a staggering 13 gigabytes, and the quality isn't even that good. If the light is just right, you might be able to identify the manufacturer's logo on the car behind you, or if you're really lucky maybe even the license plate.
To put this in context, I bought a copy of LOTR:The Return Of The King, a couple of years ago from Youtube. This is the extended version and lasts nearly 4.5 hours. If I want to download this 4.5 hour movie to my own device, in HD, it works out to 10 gigabytes.
Why on earth is it that 4+ hours of HD movie content, loaded with spectacular effects and in pinpoint clarity throughout, takes less storage space than an hour's worth of content on a dash cam?
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Why do you have the need to look at an hour or more video on your dash cam?
I only have the need for maybe the last 10 - 20 minutes, in case of an accident.
My set-up can record a total of an hour's worth but automatically removes the earliest time slots and then records again.
The system records the front and rear cameras and plays the recorded video at an accelerated speed.
Besides the internal storage, I have a 64Gb extra card installed...
some recording formats use more storage than others. .avi .mp4 H.264 H.265 there are many choices, many are not free and require a software license when you make the device. Some cheaper dash cams... use a cheaper codec that results in a large filesize. Most decent dash cams are self-grooming: they delete the oldest files automatically when they need more space.
For comparison, my 2k doorbell cam makes ~1MB per sec. But it only records on motion events, not continuously. I have other cams that record continuously, but they only keep it in RAM - they only write to the SDCard when they recognize "an event" like a human being / a face / a pet or a drastic change in light/action/motion/sound. But so far, a 64GB SDCard is perfectly adequate (~$7.99 off amazon).
Why on earth is it that 4+ hours of HD movie content, loaded with spectacular effects and in pinpoint clarity throughout, takes less storage space than an hour's worth of content on a dash cam?
right, a dashcam is just raw video, pixels times frame rate dumped without delay to avoid buffer underflow or overflow. both catastrophic without pricey editing ability. there is a reason the are like $50 starting at walmart... dashcams loop (usually user settable) until you stop it and commit it (like hey I saw that accident!) recording your 8 hour drive I would think has little use unless you are trying to apply facial rec to see if a mad dog killer appeared in frame?
if the dash cam is not needed for tv quality and you can, use 720p and 16f/s - it will be like the multiplexing used for a hotel non-hd tv channel (480p is garbage today)
ANY time you compress, you lose detail. the algorithm of the codec is what determines which detail is unimportant. in non-gray or greenscale night vision - aka day vision, low light edge detection is very poor which is why in bad conditions, it pixellates BADLY.
We recently got a dash cam setup with front and rear cameras. These record in five minute segments, amounting to about 700 Kb for the front and 400 Kb for the back, per minute of driving time. At this rate an hour's driving time works out to a staggering 13 gigabytes, and the quality isn't even that good. If the light is just right, you might be able to identify the manufacturer's logo on the car behind you, or if you're really lucky maybe even the license plate.
To put this in context, I bought a copy of LOTR:The Return Of The King, a couple of years ago from Youtube. This is the extended version and lasts nearly 4.5 hours. If I want to download this 4.5 hour movie to my own device, in HD, it works out to 10 gigabytes.
Why on earth is it that 4+ hours of HD movie content, loaded with spectacular effects and in pinpoint clarity throughout, takes less storage space than an hour's worth of content on a dash cam?
Because the video is written in real-time without too much hardware compression. With any movies you download, they take the video files and optimize it and then run through post processing compressions so they can compress the video down. Sure, better hardware can write compressed video stream in real time but that will increase cost and storage is cheap so why would you care.
I much rather have uncompressed video written since it's less likely to corrupt. That's why Dashcams write in uncompressed form in case the battery dies the file is not corrupted.
1100 kilobytes per minute total? That's 66 megabytes per hour.
This ^. your math is off
And as other's have mentioned - it's real time. There is video processing happening - so how fast the storage can be written to is a factor.
But for the most part - you're at about 66MB/hr of video. So using your 13GB number, that's almost 200 hours of video....
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