The ImageFilter module supports the following pre-defined filter types:
- BLUR
- CONTOUR
- DETAIL
- EDGE_ENHANCE
- EDGE_ENHANCE_MORE
- EMBOSS
- FIND_EDGES
- SHARPEN
- SMOOTH
- SMOOTH_MORE

Pre-Defined Filter Types (Pillow)

The ImageFilter module allows for defined filter types through various functions. These functions have different parameters based on the type, and return a filter that can be passed into an image's filter() function.
Such filters include, but are not limtied to:
- ImageFilter.BoxBlur(radius)
- ImageFilter.UnsharpMask(radius, percent, threshold)
- ImageFilter.MinFilter(size)

Other Filter Types (Pillow)

Pillow contains an ImageFilter module that contains pre-defined filters. The filter() method can be used to apply these filters onto an image instance.
```python
image.filter(filtertype)
```

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Pillow features multiple methods of adding effects or filters to images in order to modify them:
- Filters
- Point Operations
- Enhancement

Image Effects (Pillow)

https://pillow.readthedocs.io/en/stable/index.html

Pillow Documentation

Image Filters (Pillow)

The point() method in image instances can be used to transform each pixel through using a function that is applied to each pixel.
This generally follows the below syntax:
```python
output= image.point(lambda i: expression)
```

For example, the below will select all pixels and multiply them by 1.2:
```python
image.point(lambda i: i * 1.2)
```

The below will change the threshold of the image to a value of 120.
```python
threshold = 120  
image= image.point(lambda p: p > threshold and 255)
image.show()
```
Notice the "and 255" added to the expression used for the argument.. Python returns the last value examined and uses that for pixel manipulation. If p is less than the threshold value, it will not look at the "and 255" part of the expression and thus return 0. If p is greater than the threshold value, then it will look at the "and 255" portion and thus return 255.

Point Operations (Pillow)

Pillow contains the ImageEnhance module, which contains a number of classes that allow for image enhancing. In particular, these classes allow for changing the color balance, contrast, brightness, and sharpness of an image.
After creating an image enhancing object from an image, the enhance() function can be called on it with the enhancement factor as an argument. This will return the enhanced image. A factor of 1.0 returns the original image.
```python
image = enhanceobject.enhance(factor)
```

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