RussellMc wrote:
>> One thing that I can't understand is why security camera footage
>> is so crappy. When you consider that even a cheap point-and-
>> shoot digital camera takes great pictures, it seems remarkable that
>> a grainy black and white picture is regarded as acceptable in a
>> supposedly high-security building like a bank. Stills I've seen on
>> TV are so bad you can't even guess at what the person looks like
>
> It's probably about data storage.
> Which in part may be about a refusal to use a decent coding scheme.
> We have 2 x Sanyo Xacti's that record to SD cads and use "true" MP4*.
> The use of  true MP4  in a product (and certainly not including
> various "MP4 like wannabees) is IMHO a sign that the rest of the
> device is liable to be well conceived, reasonably featured and built
> by people with technical nouse. There will be exceptions.
>
> AFAIR data rate at highest resolution of 640 x 480 at ?30?
> frames/second is 1GB in 45 minutes or about
> 22MB/minute
> 370 kB/second
> 3 Mb/s
>
> 24 hours at 1 GB/hr =3D 24 GB (natch) or will fill a 1 TB drive in about =
40=20
> days.

A 640x480 cam pointed at the front door of the office, recorded 56.6 GB so=
=20
far this year (260 GB since May 16, 2007). The other two cams don't see as=
=20
much traffic so it will be a while before we fill up the 750G drive. Anothe=
r=20
benefit of motion detection is the ease of locating the part you need.

Vitaliy=20

--=20
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