Fractals Test Review
Genuine Fractals is a great program for resampling digital images to print big.
It cannot conjure high-resolution detail from lower resolution files, but it does ensure the lines and edges remain as sharp as possible when enlarging. People warn me that this program will let people steal the low-resolution copyrighted images from my website and use them for criminal purposes; it won't because it cannot replace detail that is not there. It just keeps things looking neat and sharp as they are enlarged.
Interpolation is a mathematical technique used by many digital cameras, scanners and Photoshop to create files with more pixels than the units really have. For instance, most scanners have interpolation modes to quadruple or more their resolution, and even the Nikon D1x uses interpolation to create an image 1,960 pixels tall from a CCD with only 1,324 vertical pixels.
Interpolation does not keep lines or edges sharp as images are enlarged.
You have to buy Genuine Fractals separately. Interpolation is included in most image software, especially Photoshop.
These images are 320 x 240 pixels.
Fig. 1 is a small part of an original image.
I reduced the resolution of Fig. 1 in Photoshop to 1/4 the original value, or 80 x 60 pixels. This was done the usual way as IMAGE > IMAGE SIZE > and typing 80 into the PIXEL DIMENSIONS: WIDTH (Pixels) box instead of the original 320. Make sure the RESAMPLE IMAGE box is checked and always select BICUBIC for the best results.
This gives us an 80 x 60 pixel image for Fig. 2. I don't show the smaller image because it makes no sense. I scaled it back up to 320 x 240 to fit in the window and remain deliberately pixely (nearest neighbor resampling) as it would look if you printed from this tiny image without any resampling.
Fig. 3. is a simple bicubic interpolation back to a 320 x 240 pixel image made from from the 80 x 60 image. You can do this in just about every version of Photoshop, even the free versions that come with printers and digital cameras, by going to IMAGE > IMAGE SIZE > and typing 320 into the PIXEL DIMENSIONS: WIDTH (Pixels) box instead of 80. Make sure the RESAMPLE IMAGE box is checked and always select BICUBIC for the best results.
You can see that Fig. 3., while no longer blocky and pixely as Fig. 2., still has no more detail than Fig. 2. In fact, to untrained eyes Fig. 2 probably looks sharper because of all the edge effects of all the big fat pixels.
Now the fun begins. Can we get our detail back from the low resolution image in Fig. 2?
Fig 4 was created using Genuine Fractals from the 80 x 60 pixel image. It looks similar to the simple resample in Photoshop for overall detail, but note the much smoother and sharper lines. I used the "lossless" and "maximum quality" settings of Genuine Fractals.
Genuine Fractals does very little more than a simple resample or resize in Photoshop for small amounts of interpolation. Genuine Fractals renders lines more sharply than a Photoshop resample, but provides no improvement in resolution. It does not replace missing textures, but does an awesome job on lines.
This means as you enlarge to insane amounts that you may have an image starting to appear cartoon like if you look at the output too closely, since the lines are crisp but the texture isn't there.
Genuine Fractals cannot replace lost detail or detail that is not there, however it is wonderful for upsampling from whatever image size you have.
Genuine Fractals is the best way to upsample or interpolate. Unlike the bilinear interpolation of Photoshop, it will keep sharp lines sharp, and will keep curved lines both smooth and sharp. By all means, use Genuine Fractals whenever you have to increase image size. Looking at the four images above, the first one is the best, but if you don't have that image, Genuine Fractals is by far the best way to display the image of the remaining three.
The disadvantages of Genuine Fractals are that it costs money, the .stn files cannot be opened unless another computer also has Genuine Fractals, and that it is much more difficult to use for simple image resizing than Photoshop. One must first save the file in the .stn format and then open it in a screwy and complicated dialog box. They may be updating it to work within Photoshop, which would be wonderful. Genuine Fractals also takes a long time to open a file, but that's because of all the clever math going on.
Genuine Fractals works by attempting to store an image as vector data. This works well for scaling lines at any angle, but does nothing for textures. Genuine Fractals is a lot better than a Photoshop resample for lines, although when used for rasterized text (not shown here) it really does not work anywhere near as well as it could. Even rasterized text, which ought to be great for showing off Genuine Fractals, doesn't really look any better than a simple resample in PS at small enlargements. Genuine Fractals gets much better as the magnification factors get bigger. Going to twice the linear resolution Genuine Fractals isn't much better than a simple bicubic resample, however if you are magnifying the linear dimensions by 10 times the results are far better than a Photoshop bilinear resample.
Genuine Fractals is the best way I've seen to increase the size of a raster (photographic) image. It is not magic and no replacement for having enough resolution in the first place, but if you don't have all the pixels you need, which is almost always the case when printing even with 6 MP digital cameras, Genuine Fractals is a must-have.
Interpolation is also not a replacement for legitimate image resolution. Yes, it will remove blockiness and create a larger high-resolution file, however the actual image detail remains the same as the lower resolution image. Therefore one can see clearly that one may ignore all the manufacturers' claims about digital zooming and all the other bunk about claimed resolutions other than legitimate optical resolution.
One of these methods should be used to scale a lower resolution image to the native resolution of your home inkjet printer if you do not have enough pixels from your digital camera or scanner.
In fact, one always should, in the case of EPSON photo printers, resize (bicubic) up to to 360 or 720 DPI just before printing. Photoshop does a little better conversion than the EPSON printer drivers. This is usually invisible, unless you are printing images with fine line structures like photos of sailing marinas. If you have a lot of fine lines than the Photoshop resample to 360 or 720 DPI will render diagonal lines more clearly than the EPSON driver.