Posted by Jan Panteltje on 12/26/06 15:34

On a sunny day (Tue, 26 Dec 2006 09:50:12 -0500) it happened "Steve"
<no@mail.sorry> wrote in <DEakh.3$jU4.0@newsfe11.lga>:

>I believe that in the case of that Mustek mp4 camera, the 3M pixel
>resolution is only for stills. Video is captured using 640x480 of that 3M
>pixels, period.

period? Well yo uare wrong.
It is easily tested because the picture size does not change if you press
'take picture' or 'record movie'.
Clearly the resize algo had to be present anyways,
so there is no cost overhead.
You can see that the resizin gfrom > 640x480 to 640 480 actually happens in
small steps in digital zoom mode.
It is more smooth once the area used is smaller then 640 wide pixels on the
sensor.
Different algo I gues, I write both resizes myself once for some Linux
video application I use, there are man yways to do this.


> Digital zooming uses a smaller and smaller portion of that
>640x480. No camera regardless of price uses more than 720x480 to capture
>digital video of any sort, anywhere.

Well seems this one does.
Else you would need 2 sensors or 2 different lenses to project only on part of
the sensor.

> It's all the resolution one needs to
>get the most out of NTSC TVs. If I am incorrect here, someone please jump
>in!

Well, 640x480 mpeg4 is not exactly NTSC, ist is intended to play as ASF format
on the PC in the standard 640x480 VGA resolution.
The camera _has_ a composite out too, but why bother with (PAL) in my case.

>As a test, go to a store where you can try out a camera with a long digital
>zoom (like 300 to 1 or something) and zoom all the way in. You will find
>you are looking at an image that's about 20 pixels wide!


This camera only has 8x digital zoom, so that would be 2048 / 8 = 256 pixels
wide if zoomed in.

It is not a good camera, it sucks in all aspects, the sound is rotten too,
but it fits in a shirt pocket and I have made some decent shots with it as
long as you do not pan fast.
It is the one I always have with me...
All digital, not tapes, >50 minutes on a 1GB SD card.

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