freema Sprite Processing with PixelForge
Use process_sprite to clean up existing images into game-ready sprites.
Single Sprite Processing
Remove background and auto-crop:
process_sprite
inputPath: "raw-enemy.png"
outputPath: "public/assets/games/rpg/enemy.png"
background: "chromakey"
square: true
Prefer chromakey background — uses HSV-based green screen removal. Much cleaner than black/white.
Split Sprite Sheet
Split a horizontal sprite sheet into individual frames:
process_sprite
inputPath: "animation-sheet.png"
outputPath: "public/assets/games/rpg/hero"
split: true
names: ["idle", "walk-1", "walk-2", "attack"]
background: "chromakey"
square: true
Outputs: hero-idle.png, hero-walk-1.png, hero-walk-2.png, hero-attack.png
Two-Pass Processing
When sprite sheet has white background but individual sprites have black background:
# 1. Split sheet (removes white bg between sprites)
process_sprite
inputPath: "sheet.png"
outputPath: "public/assets/sprites/char"
split: true
names: ["head", "body", "legs"]
background: "white"
square: true
# 2. Remove black bg from each sprite
process_sprite
inputPath: "public/assets/sprites/char-head.png"
background: "black"
threshold: 8
skipCrop: true
Background Removal Methods
| Background | Method | Best For |
|---|---|---|
chromakey |
HSV green screen | BEST — cleanest edges, no artifacts |
black |
Compositing equation | Dark-themed sprites |
white |
Compositing equation | Light-themed sprites |
auto |
Edge detection | Unknown backgrounds |
Options Reference
| Option | Default | Description |
|---|---|---|
background |
auto-detect | "chromakey", "black", "white", or "auto" |
threshold |
20 | Color detection sensitivity (0-255) |
square |
false | Pad output to square dimensions |
padding |
2 | Pixels of padding around content |
split |
false | Split sheet into individual sprites |
names |
0, 1, 2... | Names for split sprites |
skipCrop |
false | Keep original dimensions |
skipTransparent |
false | Don't remove background |