6.7. Stylize effects

Bleach Bypass

Bleach bypass is a technique originating in film processing, where the bleaching step was completely or partially skipped during development. Bleaching typically serves the purpose of removing silver emulsion from the film. The result is a dramatic image with high contrast and low saturation.

• Amount: Defines how much of the original image you see in relation to the bleach bypassed image. Higher values show more of the processed image, and less of the original.
• Brightness: Bleach bypass can sometimes make the image darker than desired. This control lets you adjust the brightness to compensate.
• *Silver source:*Choose which channel of the original image is used to generate the bleach bypass effect. Each option will give subtle differences, depending on the colors present in the image.
  • Luminosity: Colors are mapped to grayscale values based on their perceived brightness to the human eye.
  • Lightness: Colors are mapped to grayscale values based on their brightness relative to a similarly illuminated white.
  • Intensity: Colors are mapped to grayscale values based on the average of the RGB components.

Pixelate

Takes the image and applies an effect which looks like it was lower resolution and has been dramatically increased in size. Common use cases for it include hiding the identities of faces or number plates on cars.

• Size: Determines how big you want each pixel to be. It will then take the average color of the original pixels that was below them.
• Use original alpha: Allows you to not pixelate the alpha channel, but instead use the original alpha. This is useful if you want to pixelate the edges of say text.

Here is an example of the effect in action on a photo:

In the example below you will see pixelate applied to two pieces of text. On the left the Use original alpha is on. This means it will not pixelate the alpha channel and since the text has a solid color you do not see any difference over the original text. On the right you will se it with the Use original alpha off meaning it will pixelate the alpha channel and the edges of the text get pixelated as a result: