Talk:Demosaicing

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Contents 1 Color filter array 2 proposed merged 3 Explains why digital cameras are less good than they ought to be 4 Simple explanation of colour fringing 5 Figures missing

[edit] Color filter array

In the first paragraph, I replaced color-filtered by color-filtered because the Bayer isn't the only color filter. I hope somebody will start Color filter Array if ther is enough demand.--Marc Lacoste 11:35, 13 November 2005 (UTC)

[edit] proposed merged

I think Bayer filter#An illustrated explanation of color image reconstruction is more interesting here, Bayer Filters are less generic. --Marc Lacoste 23:41, 19 March 2006 (UTC)

Support

1. Marc Lacoste 23:41, 19 March 2006 (UTC)

Against

Done --Marc Lacoste 10:22, 15 April 2006 (UTC)

[edit] Explains why digital cameras are less good than they ought to be

I'm adding the following here, rather than the article, because I can't write it authoritatively. Hopefully someone else can re-word. The basic problem with digital cameras is that they are actually pretty hopeless! Consider viewing the output of an 8 Mpixel camera on an LCD monitor, enlarged to "1 pixel per pixel", i.e. 1 px of the image maps to 1 px on the display. The result ought to be perfect at this scale, but it is invariable poor, with either severe blurring, or very obvious colour fringing. Essentially, one ought to take the quoted Megapixel resolution of the camera and divide by 9 to obtain a resonable "truthful" resolution. (Actually, 16 would really be necessary, but image-processing can help a bit. Nevertheless, image processing cannot recover the really hight frequency spatial data which has already been lost.)

The authoritative fact is that you have been misled if you believe that a digital camera picture should appear "perfect" when displayed "1 pixel per pixel". The article does explain why, I think, but your factors of 9 and 16 are just made up exaggerations of the problem. Just stick to the reality instead of the exaggeration. Dicklyon 07:11, 13 December 2006 (UTC)

[edit] Simple explanation of colour fringing

Here's a way to explain colour fringing - it really needs a diagram. Imagine photographing a test object where the top-half is white, and the bottom-half is black. Then, the horizontal dividing line will lie over the mosaic in some way, dividing the sub-pixels. In the worst case, you will get an image with the top-half white, then a row of blue+green = turquoise, then a row of red + green = yellow, then the bottom half black. This is most unpleasant! It's even worse with purple fringes.

It's a good thing that people who develop demosaicing algorithms don't just go with the first simple thing that occurs to them, huh? Still, some problems are inevitable, since information is missing and needs to be "made up". Dicklyon 07:13, 13 December 2006 (UTC)

[edit] Figures missing

Some of the figures that were used in the article were deleted from commons, apparently for lacking a category. Then the refs to them were removed from the article, leaving extra blank lines. We can probably do fine with the images we have, with editing to patch it up. Dicklyon 21:39, 30 November 2007 (UTC)