📜 Source code available: https://git.lilys4u.com/akaneyu/bl-image-editor-plus

Image Editor Plus is an add-on that lets you modify your image in seconds. Clear, fill, flip, rotation, adjusting colors, and applying some filters in just a few clicks without external editors such as PhotoShop or Gimp.

This add-on extends the UV/Image Editor in Blender and provides the following operations.

• Cut/Copy/Paste
  
• Clear, Fill
• Crop
• Adjust hue/saturation
• Adjust brightness/contrast
• Adjust gamma
• Adjust color curve
• Replace color
  
• Flip, Rotate
• Canvas size
  
• Offset
• Apply filters

NOTE: Currently, text editing is provided as a separate add-on: Image Editor+ Text Tool

These image operations can be applied to packed/unpacked images, and reflected to the 3D model view immediately.

You can make a selection to edit the desired area on your image (currently only rectangle selection supported).

It's easy to copy/paste a selection or an entire image. The pasted images are displayed as layers, and they can be moved, rotated or scaled.

NOTE: To display pasted layers in the 3D View, you need to use a Image Layers Node instead of built-in Texture Node.

Filters

By applying the some filters, you can add special effects to your images.

• Blur
• Sharpen
• Add noise
• Pixelize (Mosaic)
• Make seamless
• Normal map
  

‘Make seamless’ filter is useful for making your image tileable. 

Normal Map Generator

Normal Map is a texture where every pixel represents a normal vector and is used to add bumps to a surface.

This add-on uses a height map (black: low, white: high) as input and can convert it to a normal map.