Enlarging low-resolution pictures with minimum of quality loss.

[aimeeandbeatles]

I have some extremely tiny pictures I found online, and would like to enlarge them to something decent looking.

What is the best solution for this? I found a program online, but its 150 bucks and the online demo did a horrible job (people looked like penguins). I tried using different things with 3 versions of Paint Shop Pro and Adobe Illustrator, but it still comes out horrible.

The pictures are 72 ppi. The only thing I can think of is to print them off and scan at a high resolution, but I'm out of printer ink. Any other solutions?

Thanks.

 

[Padma]

It is nearly impossible (despite what we see on TV) to 'blow up' a tiny, lo-res picture into something decent-looking. The information just isn't there in the picture to begin with.

 

[Till]

Try using Lanczos resampling. (Irfanview contains an implementation). But, as Padma wrote, don't expect wonders.

 

[Cutlass]

Can't be done. An image file only contains so much information. Enlarging the picture just shows the same amount of information in a larger format, which leads to quality loss. Despite what they show you on tv shows and movies, there is no software that can do more than a poor approximation of what an enhancement should look like.

For example, if someone robs a place with a security camera, the news will sometimes show a really crappy pic with a "have you seen this person" caption. So if it could be done, the cops would be doing it when trying to identify suspects.

 

[aimeeandbeatles]

All right, thank you.

I know the printing-scanning thing works, I've done it before. Just had to do a few simple photoshop edits to get a better image. I'll see if mom will let me use her printer.

 

[Genocidicbunny]

The printing-scanning thing should not work. You're still only printing out so much information, so when you scan it in, you still get only that much information, albeit somewhat smoother and better looking. But in reality, it should only blur the image, not actually make it decent.

 

[aimeeandbeatles]

Well, when I scan it at a higher resolution, and then enlarge, it works for some reason.

 

[Genocidicbunny]

Your eye simply percieves as it working. Its impossible for it to do so though. You only have a limited amount of information and the only way to increase that is to extrapolate, which all current algorithms suck at.

Its like if I take a picture and make it really sharp. There will be more apparent flaws in it than in a more blurry one.

 

[lndm]

When you zoom in on a small picture and see it all blocky....that is the most accurate it can be, end of story. Your eyes may respond better to something that has had a little smoothing, though. Whether it's printing and scanning, or manipulating with photoshop, a smoother image may appear better, but realistically it's luck if it does.

 

[Mise]

It's an optical illusion known as the Lincoln Effect.
http://www.michaelbach.de/ot/fcs_mosaic/index.html
(mouse over the blocky image of Lincoln on the left to blur it. The blurry image appears much "sharper" than the blocky one, even though it's actually blurred by a computer!)

A related phenomenon:
http://www.michaelbach.de/ot/cog_blureffects/index.html

 

[Phlegmak]

The best you could do is enlarge it in GIMP then sharpen it.

 

[Heretic_Cata]

^
I agree.

 

[DNK]

You could try a combination of sharpening and curve alteration, but even then it will be very soft looking or very contrasted or very blocky. It won't be photo-quality, although with enough work you could probably make it reasonably close if you're very skilled at that sort of thing, although it would then be effectively digital airbrushing.

 

[aimeeandbeatles]

I've tried messing around with a lot of different effects with little luck.

thanks anyways.