Safe Speed Forums

A while back there was a thread about in car cameras, and I mentioned that I was working on such a system, well I took it out for it's first successful(ish) run today and as luck would have it managed to capture someone in a mondeo estate pulling in front of me (into my side if I didn't brake) whilst trying to exit a roundabout by crossing a hatched area (admittedly with broken lines). Video at bottom of post.

The system uses my Car PC, the core of which is a Via EPIA M10000 motherboard with a 1ghz Via C3 CPU (about equivalent to a 466mhz celeron) and a USB webcam which is currently being held upside down stuffed between the passenger sunvisor and the roofliner.

The software I'm using doesn't have a webpage, but all the details can be found here: http://www.mp3car.com/vbulletin/showthread.php?t=58683

It works by recording an AVI file until a preset length or size is reached, then it starts a new AVI file, once a preset number of AVI files is reached it starts deleting the old ones and it has a button to dump the current contents into permanant storage, so that would be the MoronButton(TM) I guess.

I am encoding the video in realtime using HuffYUV, a lossless codec, I'm using about 1mb/minute at 352x288 @ 30fps and using about 96% CPU. Will probably drop to 15fps to free up a bit of CPU for my MP3s and satnav, although some people are suggesting that I should encode straight to DivX as it will use less CPU

http://www.lum.co.uk/SS/MoronCam_Test.avi

Youtube link, incase you can't play XviD: http://www.youtube.com/watch?v=Tw5GB7U9Snw (Thanks: CarlP)

I have re-encoded this video into XviD so that it becomes a 7mb file rather than a 66mb file. XviD is free and open source so everyone should be able to play it.

It highlights a few problems with the system, so far I've found:

1) Terrible performance in the sun, the road goes white and you can't see the road markings. This may be due to the reflections from the windscreen confusing the camera's level adjustments so I may have to look into mounting it outside somehow.

2) You can only see straight ahead. I have already determined that I'm about to be hit and stopped before the guy even comes into shot. It may be necessary to mount the cam in the rear of the car and use a panoramic lens of some sort

3) I have no idea if it's legally admissible, even if I do sort out problem 1 and thus make numberplates vissible.

4) It needs to be used in conjunction with a good aerial photograph of the area. You'll have to take my word for it that I did not cross any lines at all, that the other driver did, and that it's valid to make a right turn from the enterance I took. (though you can see the lines being crossed if you look in the car's shadow)

That's pretty cool actually, though I'd say 30FPS is definitely overkill, I'm sure 15 would look fine, maybe 20 if you could commit a bit more CPU to it?

Encoding DivX faster than the huff lossless sounds unlikely, but it would be shifting around a LOT less data, so maybe what you lose in time taken to compress, you'll gain in file I/O cycles (and maybe a bit of CPU). Sounds a bit hopeful though, TBH, gotta be worth a try though.

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Carl Prescott

tried the vid but "opperation failed because of certification error"
windows media player

you may want to try hosting video on www.youtube.com

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Speed limit sign radio interview. TV Snap Unhappy
“It has never been the rule in this country – I hope it never will be - that suspected criminal offences must automatically be the subject of prosecution” He added that there should be a prosecution: “wherever it appears that the offence or the circumstances of its commission is or are of such a character that a prosecution in respect thereof is required in the public interest”
This approach has been endorsed by Attorney General ever since 1951. CPS Code

"Windows Media Player cannot play the file. One or more codecs required to play the file could not be found."

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"Show me someone who says that they have never exceeded a speed limit, and I'll show you a liar, or a menace." (Austin Williams - Director, Transport Research Group)

Any views expressed in this post are personal opinions and may not represent the views of Safe Speed

You will need the XviD codec to play this:

http://www.koepi.org/xvid.shtml

Alternatively, install FFDShow and never worry about MPEG4 codecs again.

http://sourceforge.net/project/showfile ... e_id=59355

I'll sort out a youtube link later, need to sign up for an account.

In the meantime, here is basically what the video shows:


(yes there were lots of cars in L3 on the approach who were also cut in front of, and yes all the dots indicating the correct lane to enter are present on the roundabout!)

I can upload to YouTube if you want, I have the video here and account already setup?

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Carl Prescott

Go for it

It'll be here in a couple of minutes when it finishes processing:

http://www.youtube.com/watch?v=Tw5GB7U9Snw

EDIT - ...or longer, YouTube sometimes has go-slows when re-encoding the video and now looks like one of those times, it'll be done when they get round to it I guess. In the mean-time, the baby-kicking videos I chucked up there a while back are pretty funny.

http://www.youtube.com/user/fastshow

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Carl Prescott

you need to fit a polarisor and reset your shutter speed

http://www.youtube.com/watch?v=tth9krDtxII

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now retired

Another idea for easy recording is a portable media player which has a line-in recording mode. The current crop have 640x480 encoding chipsets which is much better than the previous models which had QVGA which wasn't really good enough. this one is sold very cheaply as the Evolve PMP:

http://www.supportplus.cn/supportplus_p ... ia_in2.htm

As for, cameras it is possible the electronic shutter isn't as quick as it needs to be, but I'm not really an expert in that field.

I have recorded some reasonably interesting stuff on my DriveCam, some vids are here:

http://www.attrill.co.uk/drivecam/

Gareth

and start charging other drivers to take their picture:lol:

have you got a gps or satnav with nmea output?... should be able to log that on the pc time synched with the video... and overly on google earth and all manner of geekiness.

PS i dont know if you noticed but someone seems to have tied their pom-poms to your rear view mirror.

Indeed, however timestamps are a bad idea as then they can be used to prove vehicle speed and I don't want that



That's actually meant to be one of the forest sprites from Miyazaki's My Neighbour Totoro. It doesn't normally swing about that much.

Why, is your system type approved?

I quite like the idea of this. It's also a good use for an old laptop with a broken or not so good screen.

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Andrew.

can you be forced to provide evidence to convict yourself?

Give Tony & his barmy army long enough, and they'll probably stick that one in somewhere in the not too distant future.

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What makes you think I'm drunk officer, have I got a fat bird with me?

If nice Mr Policeman formed the prior opinion that you were exceeding the speed limit then it would become corroborating evidence, and it's admissiblity would be solely down to the satisfaction of the court. Type Approval don't enter into it.

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CSCP Latin for beginners...
Ticketo ergo sum : I scam therefore I am!

so as well as the MoronButton(TM) you need a RozzerButton(R) that "accidentally" deletes all the files when you get pulled over

That's a bloody good idea. I'll be making a feature request for that I think