Filters from the Other menu can come in handy when correcting images or working with masks.
1. Maximum
This filter reduces the shades and increases the light areas.
Open your image and go to Filter>Other>Maximum. You can set the radius here. This parameter specifies the radius, inside of which the brightness of pixels is compared. After that, the pixels get assigned the maximal or the minimal brightness from the range. The whole area gets expanded or squeezed by this value (I used 1).
This is what I got:
2. Mimimum
This filter is opposite in effect to the previous one, expanding the darker areas and squeezing the highlights. You can set the radius of this filter in Filter>Other>Maximum. I selected 1 as radius value.
Here's what I got:
3. Offset
This filter shifts the image vertically and/or horizontally by the set distance. The newly created space is then filled according to the Undefined Areas mode you choose.
You can find the filter in Filter>Other>Offset. You'll also find these settings there:
Horizontal - the degree of horizontal shift; if there's a minus, the shift will occur in the other direction. (I used +64 here).
Vertical - specifies the degree of the vertical shift (I used + 61).
Wrap around - if checked, the undefined area is filled with pixels from the opposite side of the image.
Edge pixels - the color of the edge pixels is extended to where the offset pixels start (this is what I selected).
Set to Background - the area is filled with a current background color.
See what I've got:
4. High Pass
This filter reduces the overall contrast of the image, but separates the areas with the highest contrast from those with the lowest. The former are filled with the dark-grey color, the later - with light-grey.
Open the image and go to Filter > Other > High Pass. You'll see just one parameter here:
Radius - controls the thickness of the lines in the final version of the image.
This is what I have:
5. Custom
As evident from its name, this filter allows the maximal control over the changes in your image. Only you've got to be a real pro to use it to the most benefit.
If your image is already open, go to Filter>Other>Custom. You'll find the following settings there:
Grid of Text Boxes - you can enter numerical values here.
Center Text Box - represents the pixel being evaluated. Enter the value by which you want to multiply that pixel's brightness value, from -999 to +999.
Select a text box representing an adjacent pixel. Enter the value by which you want the pixel in this position multiplied.
For example, to multiply the brightness value of the pixel to the immediate right of the current pixel by 2, enter 2 in the text box to the immediate right of the center text box.
Scale - enter here the value by which to divide the sum of the brightness values of the pixels included in the calculation.
Offset - enter the value to be added to the result of the scale calculation.
Load, Save - here you can save your results for later use or load previously created presets.
This is what I've got:
Video filters
The Video submenu contains the De-Interlace and NTSC Colors filters.
De-Interlace - smoothes moving images captured on video by removing either the odd or the even interlaced lines in a video image. You can also replace the discarded lines by duplication or interpolation.
NTSC Colors - restricts the range of colors to those acceptable for television reproduction, to prevent overly intense colors from bleeding across television scan lines.
More Tutorials: 
