How to correct the usual artifacts of a bad JPEG image file
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The following tutorial was created by Philippe GREGOIRE.
I'm a 41 Belgian digital painter, living in Brussels.
I've been working with Photoshop, and other graphic programs, namely Poser and Corel Painter for a few years now.
A few weeks ago, I was told by a friend about a plug-in called AKVIS Noise Buster that could help me with my picture noise problems.
For my work I always start from photos I take by myself and I also do a lot of scans.
My main problem is to improve the photo and scan quality first because all the scanned pictures have always a lot of noise especially those that come from prints. Photos taken under bad light conditions also have a lot of noise.
The only solution I had in Photoshop was to Gaussian blur and then to Unsharp mask my source images. I was also struggling with PS noise filter to remove remaining noise. But the main point with all these tools is that whatever you try, you always loose picture sharpness and details in the end.
I then tried AKVIS Noise Buster and on my first attempt, I was immediately amazed.
It does a great job of smoothing my images without losing sharpness.
For example, in a close-up view of an image where you can see all of the skin imperfections, AKVIS Noise Buster transforms it to an image where the subject has smooth young skin while preserving the sharpness of the eyes, lips, and other details.
Sometimes you get a very bad JPEG image file.
At first sight it looks not so bad, but if you zoom a little, you'll see the typically square-pixellated design which can be found on bad JPEG's.
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That's when the AKVIS Noise Buster plug-in can be very helpful.
- Step 1. Load the JPEG file into Adobe Photoshop. Call the AKVIS Noise Buster plug-in (you just have to choose in the main Photoshop Menu Filter -> AKVIS -> Noise Buster).
- Step 2. In the Navigator, push the slider to the right until you clearly see the JPEG Artifacts in the main window.
- Step 3. Press the button Automatic Filtering.
Developer's note. In the current version just select the preset "Auto Filtering".
- Step 4. Select an area in the main window where you can easily see the differences between the processed an unprocessed parts of the image.
- Step 5. If you like the result in the preview window, click on the
button and examine your image again in the AKVIS Noise Buster plug-in window.
- Step 6. Still satisfied? Then click on the
button to apply the changes.
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- Step 7. Now you can try the plug-in with more powerful settings. Go to the History palette of Photoshop and click on the first history state (in this case "Photo SCKP0198") This will return you to the original state of the photo.
- Step 8. Call the AKVIS Noise Buster plug-in again and choose more powerful settings.
Click on the and buttons again and you get a more corrected image. Maybe you will find this one is corrected too much.
- Step 9.
If you compare the original image with the first corrected version,
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you see that the correction is good on some parts of the image (the posts and the sign) and too strong on some other parts (trees, grass...).
The solution will be to isolate these parts from one another.
- Step 10. Make a selection of the parts to be corrected. The best way is the Quick Mask Mode Method, which is described on the AKVIS Web site at the following address: http://akvis.com/en/photoshop-tips/selection-tools.php.
I chose a yellow color for highlighting the unselected area.
But it's up to you to choose another color and to highlight the selected area. Personally I usually try both methods and two or 3 different colors on the same image, depending on the dominant color of the image on which I make a selection. For changing these settings you only have to double-click on the Quick Mask Mode button in the bottom of the toolbox.
- Step 11. Then press Ctrl+J on the keyboard. You get a copy of the selected parts on a new layer.
- Step 12. You apply the AKVIS Noise Buster plug-in (as described here before) on layer 1 only and you get an excellent image, where the posts and the sign are corrected and the grass remains perfect.
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