Image blending functions

Image blending and compositing tools from MIMT

These tools effect image blending and masking functionality common in image manipulation applications such as GIMP, Krita, or Photoshop. For a layered image composition GUI based on this functionality, see the parent toolbox linked below.

================== BLENDING FUNCTION ==================

IMBLEND() can blend images or imagesets as one would blend layers in GIMP or Photoshop. See 'help imblend'

I assert that if nothing else, IMBLEND() stands as the single most comprehensive collection and demonstration of blend mode math from GIMP, ImageMagick, Photoshop, Krita, and elsewhere.

Inputs are image arrays of same H,V dimension; both can be single images or 4-D imagesets of equal length.

-- Mismatches of dimensions 1:2 are not supported. Use IMRESIZE, IMCROP, or PADARRAY

 to enforce desired colocation of layer content.

-- Mismatches of dimension 3:4 are handled by array expansion.

-- Either image may be replaced with a simple color tuple, with implicit expansion.

User can optionally specify compositing method independently of the blend method.

Unlike other image manipulation software, most blend and composition modes have been made parametric. This useful feature may allow the user to tailor the influence of blends in a manner which cannot be acheived using mixdown opacity, or control density/thresholding behavior in composition modes. See the synopsis for details.

This collection of blend modes is comprehensive; if a mode is not on this list, it is likely equivalent to one of the modes that is. The list of supported mode synonyms is in the synopsis.

Submission thumbnail shows contour plots for the majority of the non-component blend modes. Included in the zip file is a PDF containing this sheet as well as parameter sweeps and documentation of mathematical properties and relationships among modes.

COMPOSITION MODES:

• gimp compatibility (default)
• translucent
• dissolve (8 variants)
• src over
• src atop
• src in
• src out
• dst over
• dst atop
• dst in
• dst out
• xor

BLEND MODES:

██ Bidirectional Modes

==== Contrast & Mixing ====

• softlight (5 variants)
• overlay
• hard light
• linear light
• vivid light
• easy light
• flat light (3 variants)
• mean light (2 variants)
• super light
• star light
• moon light (2 variants)
• pin light
• hard mix (3 variants)
• fog lighten
• fog darken

==== Penumbrae ====

• penumbra A (3 variants)
• penumbra B (3 variants)

==== Quadratics ====

• glow
• heat
• reflect
• freeze
• frect
• reeze
• helow
• gleat

==== Mean-Scaled ====

• scale add
• scale mult
• contrast

██ Unidirectional Complementary Pairs

==== Dodges & Burns ====

• color dodge & burn
• poly dodge & burn
• linear dodge & burn
• easy dodge & burn
• gamma dodge & burn
• suau dodge & burn
• maleki dodge & burn

==== Hybrid Glow & Shadow ====

• flat glow & shadow
• mean glow & shadow
• star glow & shadow
• moon glow & shadow (2 variants)

==== Krita/EB Assortment ====

• tint & shade
• lighteneb & darkeneb

██ Relational

• lighten RGB
• darken RGB
• lighten Y
• darken Y
• saturate
• desaturate
• most sat
• least sat
• near
• far
• replace
• preserve

██ Mathematic & Technical

• multiply
• screen
• divide
• addition
• subtraction
• bleach
• stain
• difference
• phoenix
• exclusion
• negation
• sqrtdiff
• average
• agm
• geometric
• ghm
• harmonic
• interpolate
• hard int
• pnorm
• arctan
• curves
• gammalight
• gammadark
• grain extract
• grain merge

██ Mesh Modes

• mesh
• bomb
• bomblocked
• hard bomb

██ Selected Mesh Presets

• lcd
• +4 others

██ Modulo Modes

• mod
• mod shift
• mod divide
• cmod
• cmod shift
• cmod divide

██ Component

• hue
• saturation
• color (12 variants)
• value
• luma (2 variants)
• lightness
• intensity
• transfer inchan>outchan (directly transfer any channel to another)
• permute inchan>H (rotate hue)
• permute inchan>HS (rotate hue and blend saturation)

██ Specialty Modes

• recolor {colormodel}
• blurmap {kernel}

================== MASKING FUNCTION ==================

Also included is REPLACEPIXELS() which effects an opacity blending similar to GIMP's 'Layer Mask' functionality. Accepts two input images and a mask. Foreground image may be replaced by a color triplet for convenience. REPLACEPIXELS() supports multichannel and multiframe masks, and can support NaN throughput if mask is logical. REPLACEPIXELS() can optionally perform masking in linear RGB.

Archive includes support functions for image conversion and typecasting. IP Toolbox is not required.

Documentation with commentary, example code, and input/output images is available here:

http://mimtdocs.rf.gd/manual/html/imblend.html

This is part of my image manipulation toolbox:

http://www.mathworks.com/matlabcentral/fileexchange/53786-image-manipulation-toolbox