My mom has some unfortunately low resolution images that she wants to print at 8"x10" or larger for her upcoming birthday party. I have the Adobe CS4 Suite of products… does anyone know the best way to enlarge these images with the least icky artifacts in them?
I think it most certainly will depend on the original, but with very low resolution images I often use Photoshop to resample them (using Image Size) at a higher PPI (pixels per inch), e.g. 300 ppi. The image may appear a little blurrier, but it will minimize the effect of actual visible pixels. It may take some experimentation. Ultimately (and unfortunately) in most cases it’s Garbage-In-Garbage-Out.
Yup, there’s not a whole lot you can do to create information where it doesn’t exist. You can use software to extrapolate via fractals (like Enlarger PRO and Genuine Fractals) which give you some benefits if the original is clean.
I’m so sorry. There is no such thing as zoom and enhance.
Opal, when faced with similar situations, I’ve enlarged the picture (increasing resolution), and then applied some artsy filter to it (simulated brushstrokes or something). It doesn’t look like a photo anymore, but at least it looks somewhat artistic instead of just looking crappy.
Are they low resolution JPEGs, some other format, or old prints from film? I’ve used Easythumbnails to enlarge JPEGs, but the result depends on how highly compressed the source JPEGs are. If they’re highly compressed, you get high resolution compression artifacts. If they’re good quality JPEGs, it can look pretty good.
EasyThumbnails is free Windows software, so if you’re running windows, it’s easy to try it. You have to select the right interpolation algorithm, but I’m on Linux right now, and can’t remember what it’s called. It’ll come to me during the edit window (cross fingers).
ETA: Lanczos! And there’s a wikipedia page on the algorithm and everything! Check out the example.
ETA2: You need to select “enlarge” for it to make larger images. The default is to make thumbnails.
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Opal, when faced with similar situations, I’ve enlarged the picture (increasing resolution), and then applied some artsy filter to it (simulated brushstrokes or something). It doesn’t look like a photo anymore, but at least it looks somewhat artistic instead of just looking crappy.
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Yes, if you really don’t need it to match the original, you can use effects like posterizing or the “palette knife” filter.
Genuine Fractals (now called Perfect Resize), as Telemark mentioned, can do very impressive things with enlargement. I have some amazing looking huge prints made via Perfect Resize. However, that’s taking full sized DSLR images to poster size. It’s designed for taking reasonable resolution images and enlarging them to very large sizes, not taking super low resolution images and making them into normal sized prints. I suspect the results wouldn’t be as good in that situation. They do have a free demo, so you can try it out and see if it gives you the results you want.
Assuming it is a digital photo.
Here is what you want to do. You resample/resize the photo. So there are something like 9, 16, 25, 36, 49 more pixels (note those numbers are the squares of 3,4,5,6,7). If the pic in question is pretty low resolution you need the higher number. If its just not quite good enough, you use the lower number.
That turns one pixel into something like, for example, 9 pixels (3 by 3 pixels) that are the same as the pixel they are based on. Then, you use something like a blurring filter (it really helps if the program is sophisticated enough that you can define the number of pixels it blurs over) that “smooths” over an area about the size of resizing you’ve choosen (like 3 by 3 if thats what you have chosen).
Now, the new picture will not have anymore resolution than the old one. But, if the problem is the number of pixels you have to work with, at least the new picture will not show blocky pixels when overly enlarged. A slightly blurry photo in my opinion looks much better than one that you can see the pixels.
After you have done all that, sometimes something like a “sharpen” filter will spiff things up a bit.
Oh, and rather than work with the whole photo. Cut and past a small section of it first and zoom in on it while you are trying these various things. Something like a small section of the face (eyes are always good). Once you figure out what to do to make it look good without being too pixely or blurry, then go back and do the same thing to the whole photo.
Depending on the subject matter (particularly, the amount of contrast), it’s sometimes possible to get good results by tracing to vector. it doesnt recreate lost detail (nothing can), but it does help eliminate ‘jaggies’.
No idea how to do this in CS4, but Inkscape (open source) will do it.
Thanks for the tips everyone. I’ll see what kind of results I can get this weekend.
Define “low res.” It also depends on the quality of those pixels and your post-processing skills (mostly sharpening.) I have a 13x19 of a 2.7 MP file taken on a Nikon D1 framed in my study that looks great. It’s obviously up sampled if you look at it very closely, but from normal to relatively close viewing distances nobody is going to care or even see the difference.
Genuine Fractals is the best up-sizing program I’ve see , but stair stepping (increasing size a fixed percentage, say 10% at a time, until you reach your target size) also works slightly better than sizing up directly to your final size.
Now, if by “low res” you mean web-sized, you are in a pickle.
That’s deblurring images that already contain most of the information of the resulting images, just layered on top of other information. Part of the algorithm may work some magic on enlarged images, but the miraculous results shown require blurred rather than low-res images, and images blurred in particular manners even.
I’ve seen that video and the potential does look good for photos that have a particular kind of motion blur. Unfortunately for the OP, she’s dealing with a completely different challenge.
I use this method quite often. You’ll generally have to edit the image again afterwards, but it does help a lot. Better vector programs, like Vector Magic*, make it even better.
*It’s expensive to buy, but if you only have a few photos, it’s not that bad to use the online version on a per image basis.