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The Photo Viewer integrated in Windows 7 is showing pixels when I zoom in pictures:

enter image description here

I remember in Windows XP there weren't any pixels - everything was smooth.

As an example, I made a screenshot of a web page with a Firefox plugin and a screenshot of an Excel document with Evernote. Both are .PNG formats.

Here is the video

I have filmed myself using magnifier which you can see here

Note: set video playback to 720p HD in the lower right corner of the YouTube interface before playing the video.

How can I fix this?

P.S. I have 14" Matte screen laptop. Does it have something to do with this?

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By the way, the second video (of you using Magnifier) is set to private so we can't watch it. – Ben Richards Aug 29 '11 at 5:01
It is now watchable. – Boris_yo Aug 30 '11 at 5:52
up vote 6 down vote accepted

This is simple, but a guess, unless you can tell me otherwise.

a .PNG file is capable to storing vector based graphics, but in most situations, when/if you are taking a screenshot or similar, it is stored as raster graphics / bitmap.

So, if you are zooming in to a (bitmap/raster based) picture, typically, the system will attempt to automatically "antialias the image by filling in the gaps with other colours that make the image look more pleasant and easy on the eye.

enter image description here

(Left Default bitmap image zoomed in, right bitmap image with Anti Aliasing on).

Now, we get in to Vector Graphics - A vector graphic doesn't actually store the picture as pixels, it instead stores the picture as vectors or points. For example, if trying to describe a square, it would say, a line exists between A and B, B and C, C and D, D and A. The system then will draw (Render? Not sure on the term), that image at ANY zoom level, and it will look perfect.

In the same sort of way, True Type Fonts are Vectors:

enter image description here

This means that in any application such as word, you can zoom in or choose a font of size 500, and the font will look perfect. However, if you took a picture of the same instance of Microsoft Word and tried to zoom in, it will be a bitmap image that is saved and it will not look pleasant zoomed in past 100%.

AFAIK, it is not possible to take a vector screenshot.

To sum everything up, here is one last picture from Wikipedia. There is a high quality vector image of a bottle. When you export a section as bitmap, and the same as vector, then zoom in, here are the results:

enter image description here

And finally, if we are talking about the exact same image on both of your machines, but it just looks bad on your new one, if you have not enabled Clear Type (which should be on by default), it could be that your newer screen has a lower DPI, making images more "blocky"/pixelated.

You can test this by a simple formulae - (Screen Resolution * Screen Resultion) / inches (Providing your new screen is at the same aspect ratio). The higher the better.

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That is awesome answer William! Are you aware of any free edge smoothing application? – Boris_yo Aug 30 '11 at 5:53
@Boris_yo - You can't add detail where there isn't any... There are some utilities out there, that can zoom and sharpen slightly, but, I can't think of any off the top of my head that do it for certain... I suppose you could try Paint.Net (just can't remember for sure) :( Sorry – William Hilsum Aug 30 '11 at 11:05

What is going on is a programmatic choice difference between Windows XP and 7. In Windows XP, the photo viewer, when zooming the image past 100% scaling, would use an algorithm to smooth out hard edges. This is antialiasing. Because the image does not contain unlimited information since it doesn't have an unlimited resolution, if it is not smoothed after being zoomed, it will look blocky, like in Windows 7. Pixels, the individual dots making up an image, are rectangular, so when you zoom in on an image past 100%, you are basically taking a small rectangular point and blowing it up to a larger rectangular point. Windows XP performed a post process on zoomed in images to smooth out this blockiness.

If you want an image viewer that does this kind of post process when zooming in, I find that Google Picasa works well. However, don't expect to gain any new detail this way. It cannot create detail where there isn't any (despite what TV crime dramas may try to suggest). You can't change the behavior of the Windows Photo Viewer. So, installing a 3rd party option is really your best bet.

And no, the type of screen that you have installed has nothing to do with it. This is purely a software-side thing.

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I think this is the correct answer - the Win 7 "windows Photo Viewer" simply makes no attempt at smoothing the render of enlarged images. In XP you could see a similar thing in MSPAINT when zooming. – jtreser Aug 28 '11 at 0:48
@sidran32 Thanks. Do you know if ACDsee has edge smoothing? – Boris_yo Aug 30 '11 at 5:54
@Boris_yo I do not. I have never used that software, sorry. – Ben Richards Aug 30 '11 at 14:52

I believe these "pixels" you are talking about are due to anti-aliasing. Displays are incapable of creating straight lines at an angle, as well as curves. Windows, as well as other programs use anti aliasing techniques to trick the eye into thinking the image is better than it is. These pixels are virtually invisible at the proper resolution, however when the screen is captured and zoomed, they stick out.

Look at this wikipedia article on anti-aliasing to learn more.

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Anti-aliasing has to do with the display of text, not with pictures. It pertains to fonts and their display at sizes for which they were not optimized. Once the text is captured in an image, anti-aliasing is over and doesn't come into it at all. – harrymc Aug 23 '11 at 6:22
before the OP posted a screenshot, I thought he was talking about the shaded pixels showing up when zoomed. Now I see he is referring to the graphics rendered trying to scale the image while zooming. However, harrymc, when a font or image has been AAed and captured, zooming shows the artifacts. AA does come into it. – Keltari Aug 23 '11 at 6:57
AA is the property of a font and is used when generating the glyphs for the characters. Once the glyphs are generated, AA is done and finished. A photo viewer only views captured glyphs pixel-by-pixel and does not regenerate them using AA. Even an AA glyph will look ugly when magnified - one needs to regenerate the glyph with AA from the font and using a larger font-size to do better (which a photo viewer does not do). – harrymc Aug 23 '11 at 8:07

Your recollection of WinXp versus Win7 is correct.

I've recently noticed this difference between the photo viewers of Windows XP and Windows 7 also. The Win 7 viewer simply does a quick and dirty scaling (throw away pixels or just replicate pixels) of the image if you're viewing at anything other than 1:1 pixel mapping. The XP photo & fax viewer does a much better job of scaling. Diagonal lines/edges in the XP viewer will be smoothed out when downscaling or upscaling, whereas the same image in 7 will be a staircase or jaggies. Really a step backwards by Microsoft! I suspect there is nothing to do but find another photo viewer for Win7.

BTW all viewing was on a CRT computer monitor (dual-boot system), so your LCD display is not a factor.

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Not everything scales up correctly when zooming, since pixels cannot appear from nowhere.

The zooming of a picture entails very simply the "widening" of the pixels, so that each pixel is displayed as more than one pixel. The result is that the picture becomes "blocky", where each original pixel is shown as a block of several pixels. The quality of the zoom depends on the ability of the zoom software to "invent" pixels where there are none, so as to avoid too many artifacts.

I do not believe in the degradation of the quality of the zoom in Photo Viewer, but I believe that you have fallen into another trap of Windows 7 : The text is "sprinkled" with pixels intended to give it a beautiful 3D look. However, this beautiful text does not scale up : When zomming one sees all the scattered pixels.

To take screenshots, the solution is to change your tool. Use instead the Windows 7 Sniping Tool, which does not capture these extra pixels. The results then scale up much better.

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