Archived posting to the Leica Users Group, 1999/08/18
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]Thanks Jim, I would like to be sure to understand. Do you state that if I buy a "1024*768" camera, I'll get 256*192 pictures once I'll will have them transfered on my PC? :-o or Do you state that if I read the *technical sheet about the CCD* of the camera and read that it has a "resolution" of 4096*3072, I'll will get 1024*768 pictures? --- Jean-Claude Berger (jcberger@jcberger.com) Systems and RDBMS consultant (MCSE), Lyon, France http://www.jcberger.com > -----Original Message----- > From: owner-leica-users@mejac.palo-alto.ca.us > [mailto:owner-leica-users@mejac.palo-alto.ca.us]On Behalf > Of Jim Brick > Sent: Friday, August 13, 1999 4:22 PM > To: leica-users@mejac.palo-alto.ca.us > Subject: [Leica] RE: Erwin's adventures in digiland. part 1 and 2 > > > This is correct. It takes 4 pixels in the camera, to record > one image > pixel. The stated resolution of consumer digital cameras > must be divided by > four to get the "real" resolution. > > Each row of pixels on the sensor contain only two colors. > One row of: > > RGRGRGRGRGRGRG... > > and the following row: > > GBGBGBGBGBGBGB... > > Then: > > RGRGRGRGRGRGRG... > > and > > GBGBGBGBGBGBGB... > > so the rows look like this: > > RGRGRGRG... > GBGBGBGB... > RGRGRGRG... > GBGBGBGB... > > Draw a square around four pixels: > > RG > GB > > and you have the four pixels required to make up the single > image pixel. As > Rob said, one RED, one BLUE, and two GREEN pixels per image pixel. > > There are variations, but for the most part, the above is > true. All brand > name consumer CCD cameras that I know of are as I described above. > > Jim > > > > At 12:32 AM 8/14/99 +1000, you wrote: > >On 13 Aug 99, at 14:52, Jean-Claude Berger wrote: > > > >> Hello Erwin, > >> > >> Could this be a typo? I thought that each pixel was > represented by 24 or > >> 48 bits. How can 4 pixels represent 1 pixel? > >> > >> > interpolation. Remember that 4 pixels are needed to record > >> > one image > >> > pixel. > > > >Jean-Claude, > > > >Erwin's comment referred to the capture of images via > digital camera. The > >capture array in these devices is a regular square matrix > ie colour reception > >elements are placed in a 2x2 dot matrix, not triplets like > on a conventional > >CRT. AFAIK the matrix consists of a blue, red and two > green sensitive > >pixels, since more information in the green band is > desirable as green is the > >frequency to which human sight is most sensitive and > subsequently most > >critical. Unfortunately I can't seem to find Jim Brick's > (?) excellent post > >from > >many months ago which outlined the subject. > > > >Cheers, > > > >Rob Studdert > >HURSTVILLE AUSTRALIA > >Tel +61-2-9554-4110 > >Fax +61-2-9554-9259 > >UTC(GMT) +10 Hours > >audiob@ozemail.com.au > >http://www.ozemail.com.au/~distudio/pagelist.html > >