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Re: [pwc] Philips ToUCam Pro PCVC740K: Grab still images

To: Philips Webcam Linux Driver <>
Subject: Re: [pwc] Philips ToUCam Pro PCVC740K: Grab still images
From: "" <>
Date: Thu, 30 Jun 2005 22:04:35 +0300
On Thu, Jun 30, 2005 at 08:37:25PM +0200, Kermit wrote:
> > The hardware sensor is 640x480.
> > It doens't have any sense grab 1280x960 .
> > Just grab 640x480 and then use #> gimp :) for example.
> 
> Really? I thought that I bought a "Megapixel Webcam" :(
> Does the Philips ms windows-software really just scale still images?
> 
> I feel fooled :(

Hmm...this hasn't been discussed here before I believe.

Philips sensor is CCD 640x480 pixels, but as it is CCD, it has roar and
white noise always present. If you take several, say 4, pictures
one right after another, some pixels will have surely different RGB
values in different frames also from the still scene. Darker it is, more 
noise there will be.

If four 640x480 frames are taken, then extrapoloited smartly to a 
1024x960 image, it will have more information than just taking one 640x480 
frame and double it in size. Yes, "information" not just pixels.

I don't think there is a program for Linux which would enable to use
this property of CCD-cell. Maybe someone knows how to make it with Image
Magic quickly? But I believe the webcam's program in MS Windows does
just this when taking and claiming to take 1Mpix-images.

// jouni

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