Remove Checkerboard | 去除棋盘格背景

English | 中文

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English

A portable Agent Skill that removes backgrounds from images to produce real transparent PNGs. Auto-detects and handles two background types:

1. Fake checkerboard: AI generators (ChatGPT, Gemini, DALL·E) sometimes render the visual symbol of transparency (gray-white grid) as actual pixels instead of a real alpha channel.
2. Solid/white background: flat white or light-colored backgrounds that need to become transparent.

The script auto-detects which type — you don't choose.

Quick start

# Default: BiRefNet engine + feather 4 (best quality, needs GPU)
python scripts/remove_checkerboard.py input.png -o ./output --engine birefnet --feather 4

# Batch a folder (mixed checkerboard + white-bg images is fine)
python scripts/remove_checkerboard.py ./images -o ./output --engine birefnet --feather 4

# CPU-only (rembg, no GPU needed)
python scripts/remove_checkerboard.py input.png --engine rembg --feather 4

Engines

When to trigger

• "Remove the checkered background"
• "Make white background transparent"
• "Extract subject from image"
• "去背景" / "去白底" / "棋盘格背景" / "假透明" / "抠图"
• AI-generated images where transparency looks broken

Project structure

remove-checkerboard/
├── SKILL.md                            Routing rules and detection logic
├── scripts/
│   ├── remove_checkerboard.py          Core: auto-detect + remove background
│   └── test_remove_checkerboard.py     Unit tests
└── references/
    ├── algorithm.md                    Detection algorithm explanation
    ├── engine-guide.md                 BiRefNet vs rembg engine comparison
    └── tuning.md                       Feather / threshold tuning guide

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中文

可移植 Agent Skill，从图片中去除背景，生成真正的透明 PNG。自动识别处理两类背景：

1. 假棋盘格：AI 生成器（ChatGPT、Gemini、DALL·E）有时会把透明的视觉符号（灰白网格）渲染成真实像素，而不是真正的 alpha 通道。
2. 纯色/白底：需要变透明的纯白或浅色背景。

脚本自动识别类型——无需手动选择。

快速开始

# 默认：BiRefNet 引擎 + 羽化 4（最佳质量，需 GPU）
python scripts/remove_checkerboard.py input.png -o ./output --engine birefnet --feather 4

# 批量处理（棋盘格 + 白底混合图片可一起处理）
python scripts/remove_checkerboard.py ./images -o ./output --engine birefnet --feather 4

# 仅 CPU（rembg，无需 GPU）
python scripts/remove_checkerboard.py input.png --engine rembg --feather 4

引擎对比

触发场景

• "去除棋盘格背景"
• "把白底变成透明"
• "从图片中抠出主体"
• AI 生成图片透明度看起来坏了

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License | 协议

MIT