Its last release was 2.0.0, in 2004, but unlike Refocus no one that I am aware of is putting effort into making sure it remains compatible with newer versions of the GIMP.įedora provides the plugin as the gimp-refocus-it package, but users of other distros will probably need to compile from source. The other helpful GIMP plugin is named Iterative Refocus (or refocus-it). Of course, one of Unshake’s selling points is that it performs its own automatic tweaking, thus producing higher-quality output. In my tests, Refocus was drastically faster than Unshake, taking less than five seconds than to deblur an image that required 30 or 40 in the latter program. Roughly speaking, the Radius and Matrix Size controls determine how small a blur the algorithm will detect, and the Gauss, Correlation, and Noise controls affect the degree of smoothness and pixelization artifacts to allow. It is not easy to explain the parameters without delving into deconvolution math, but you can play around with the settings. The tool has five parameters and a preview window. You start Refocus from within the GIMP, in Filters -> Enhance menu. Debian and Ubuntu include Lemieux’s version as 0.9.1 in their package managers. Richard Lemieux and Peter Heckert each maintain a page for their respective patched versions. That release is from 2003, though, and several other developers have released their own patches to bring Refocus compatibility up to modern versions of the GIMP. The first is Refocus, which is officially at version 0.9.0. Both are open source, although neither of them seems to be undergoing active development. The GIMP has two third-party plugins that do the same kind of correction as Unshake. Cahill notes on the Unshake site that he has never seen the algorithm come close to the “x100” time allotment - he just put it in as an upper bound to make sure the program exits. You can turn the Time parameter all the way to “x100” if you want the algorithm to perform more detailed analysis.Īt the default settings, 40 to 50 seconds is a reasonable estimate time for a 1.3 megapixel image. By default it is set to “x1” meaning that Unshake will perform its transformations within the Estimate time. The Time control allows you to allot more or less time to Unshake’s process. The actual processing time can vary greatly depending on what it decides. Unshake attempts to determine on its own how much correction to apply. Unshake will perform the image correction and open the result in a new window, which you can then save. To see the results, just click the DeBlur button. You can adjust the blur severity and correction quality parameters and get new estimates. When the window is properly set, click on the Estimate button and Unshake will give its best guess as to how long the process will take. If you choose the wrong portion of the image, Unshake could misidentify portions of it as blur and overdo the correction. This is a critical step, and one that the interface does not explain to you. When you open a photo, you start by resizing the photo window to show just the portion of the image that you are most concerned about. The interface has controls at the top, a status window beneath them, and a clickable file selection widget at the very bottom. You can unpack the distribution anywhere on your system and launch the app by running. #Unshaky software licenseUnshake is closed source, and the license prevents use for commercial purposes. The latest release is 1.5, which requires Java 2 or greater. The most straightforward way to get started is with Mark Cahill’s Unshake, a small Java app with a lot of options that performs some helpful guesswork to speed things up. It is a CPU-intensive process, but for a shaky image there is no better use of your MHz. In a nutshell, it involves taking the Fast Fourier Transform of the image (which makes it easier to see the tell-tale signs of blurring), smoothing out the artifacts, then transforming the image back into its original form. If you want to understand the math behind the process, start with the articles referenced at Wikipedia and you can find as much detail as you want. Several Linux-friendly utilities can help you.ĭeconvolution is the general process that helps remove the effects of camera shake and blur. But in the digital era, there is no need to despair - you can remove shake and blur from your pictures after the fact. Whether by wind, vibration, or shaky hand, we have all taken blurry photos.
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