Filters from the Blur menu blur the image, averaging neighboring pixels in areas of most contrast. You can use this effect for many purposes, for instance, to create a background for a text or an important element, or to imitate motion. Most often, though, the filter is used to get rid of small defects in photography like dust, cracks, noise created by scanning, grain created by other filters.
1. Average
This filter counts the average color value of all the selected pixels and fills everything with the averaged color.
So, open the image and go to Filter>Blur>Average. If you apply it to this particular image, you'll get the whole canvas filled with the color #c5b1a0 .
2. Blur
This filter blurs the image, averaging the neighboring pixels in the areas of contrast.
You can get to it through Filter>Blur>Blur. As the filter has no setting, you should get a similar picture.
3. Blur More
This filter is essentially the same as the previous one, but it blurs the image to a greater extent. This filter, which you can find in Filter>Blur>Blur More, does not have settings, either. So, here's approximately what you'll have:
4. Box Blur
This filter blurs an image based on the average color value of neighboring pixels.
After you've opened the image, go to Filter>Blur>Box Blur. There you'll see just one setting:
Radius - adjusts the size of the area used to calculate the average value for a given pixel (I used 4).
And here's what I got:
5. Gaussian Blur
This filter blurs the edges by the Gauss distribution, i.e. along the bell-shaped curve. So, the blur effect is most evident in the center. It fades off profoundly towards the edges of the image.
In Filter>Blur>Gaussian Blur, you'll see just one Radius parameter again:
It determines the degree of blurring the picture. If the value is very high, you'll get a uniform ground from your image (I set it to 1,5).
And here ' s what I have :
6. Lens Blur
Adds blur to an image, leaving some objects in focus. You can use simple selection to determine which areas are blurred, or you can provide a separate alpha channel depth map to describe exactly how you want the blur added.
So, go to Filter>Blur>Lens Blur. You'll see the following settings:
Preview - lets you set or remove the preview of the image. You can also set the fast preview (Faster) , or a more natural one (More Accurate).
Depth map - allows choosing the source to work with, with the following options: None, Transparency, Layer Mask ( I selected Transparency).
- Blur Focal Distance - sets the depth, at which pixels are in focus. For example, if you set the focal distance to 100, pixels at 1 and at 255 will be completely blurred, and pixels closer to 100 will get blurred less ( I used 158).
- Invert - if checked, inverts the selection or the alpha channel you're using as the depth map source.
Iris - simulates a real life camera.
- Shape - sets the type of shape of the iris ( I used Hexagon).
- Radius - determines the amount of blurring, like in the Gaussian Blur effect ( I set it to 17).
- Blade Curvature - softens the curves.
- Rotation - sets the angle of the blur.
Specular Highlights.
- Brightness - increases the brightness of the highlights.
- Threshold - select a brightness cutoff, i.e. all pixels brighter than the cutoff value are treated as specular highlights
Noise - adds noise to the picture.
- Amount - determines the amount of noise ( I used 2).
Distribution - allows selecting the type of noise - Uniform or Gaussian.
Monochromatic - adds noise without affecting color ( I unchecked it ).
7. Motion Blur
This filter lets you create the motion effect. It blurs an image under a set angle. The blur effect is achieved due to multiple duplications of the image and displacement of the duplicates next to each other with a set interval. The further the duplicate from the initial image, the more transparent it gets.
You'll find the filter's settings in Filter>Blur>Motion Blur.
Angle - sets the angle of blurring.
Distance - controls the degree of blurring.
And here's my result:
8. Radial Blur
This filter enables blurring within a concentric circle, from the focal point in all directions.
If your image is already open, go to Filter>Blur>Radial Blur. That's what you'll see there:
Amount - determines the value of blurring. The further from the center, the more spinning there'll be (I used 10)
Blur method - can be either Spin и Zoom ( I selected zoom).
Quality - controls the quality of blurring. The better the quality, the more time is needed to process the image (I used Good).
And this is my result:
9. Shape Blur
Uses the specified kernel to create the blur.
You can find this filter in Filter>Blur>Shape Blur, with these settings:
Radius - determines the size of the kernel; the larger the kernel, the greater the blur.
Shape - you can choose a kernel from the list of custom shape presets or load different shape libraries by clicking the triangle and choosing from the list.
10. Smart Blur
This filter lets you get rid of grain, stains and dust. It blurs only the more or less uniform areas with low contrast without affecting the edges of an image.
You should go to Filter>Blur>Smart Blur. You'll see these settings:
Radius - sets the distance for comparing and processing pixels (I used 3).
Threshold - sets the cutoff contrast level of pixels . The filter averages the adjacent pixels if their contrast is lower than this value. The higher the threshold, the more areas will be blurred (I set it to 25).
Quality - just like in Radial Blur, this parameter controls the quality of blurring. The better the quality, the more time is needed to process the image (I chose Medium here).
Mode - sets the parameters for filter processing : for the entire selection ( Normal ), for the edges (Edge Only) or for the color transitions (Overlay). Normal applies significant contrast, Edge Only applies black-and-white edges, and Overlay applies white.
11. Surface
This filter Blurs an image while preserving edges. It can be used to create special effects and to remove noise and grain.
In Filter>Blur>Surface, you'll see the following settings:
Radius - determines the size of the area selected for the blur (I used 5).
Treshold - specifies how much the tonal values of neighboring pixels must diverge from the center pixel value to become part of the blur ( I set it to 15).
Marvel at my final result and enjoy using these valuable filters!
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