diff --git a/README.md b/README.md index 0f9d9ac..e143a2a 100644 --- a/README.md +++ b/README.md @@ -136,6 +136,21 @@ Enter comma-separated hex colors (e.g., `#FF0000,#00FF00,#0000FF`). Each color a - **start_step / end_step**: Step range for intervention. Paper optimal: 8–10 of 50 steps. - **mask**: Optional. Bilinearly downsampled to patch grid for localized control. +## LCS vs Post-Processing + +LCS operates **during** diffusion sampling, not after — this is the key difference from traditional color grading. + +| | Post-Processing | LCS | +|---|---|---| +| **When** | After VAE decode, in pixel space | During sampling, in latent space | +| **Mechanism** | Color filter on the final image | Modifies 3D color subspace mid-generation | +| **Model awareness** | None — structure is already locked | Model adapts to color shifts in subsequent steps | +| **Result** | Colors can look "painted on" — shadows/skin tones may shift unnaturally | Colors look like the model intended them — content harmonizes naturally | + +Example: for a warm orange sunset, post-processing tints everything orange (muddying shadows), while LCS nudges colors early in sampling so the model generates clouds, lighting, and reflections that are *coherent* with warm tones. + +The paper's core insight: color and structure are **orthogonal** in the latent patch space, so you can steer one without disturbing the other — impossible in pixel space where they are entangled. + ## How It Works 1. **Project**: Convert denoised prediction to 64D patch space, project onto 3D LCS basis diff --git a/README_zh.md b/README_zh.md index 63dbd21..d3e2fa4 100644 --- a/README_zh.md +++ b/README_zh.md @@ -135,6 +135,21 @@ LCS Load Data → LCS Color Batch → KSampler - **start_step / end_step**:干预步骤范围。论文最优:50 步中的第 8–10 步。 - **mask**:可选。双线性下采样至 patch 网格分辨率,用于局部控制。 +## LCS 与后处理的区别 + +LCS 在扩散采样**过程中**操作,而非生成后——这是与传统调色的核心区别。 + +| | 后处理 | LCS | +|---|---|---| +| **时机** | VAE 解码后,在像素空间 | 采样过程中,在潜在空间 | +| **机制** | 对最终图像施加颜色滤镜 | 在生成中途修改 3D 颜色子空间 | +| **模型感知** | 无——结构已经定型 | 模型在后续步骤中自适应颜色偏移 | +| **效果** | 颜色可能看起来像"涂上去的"——阴影/肤色容易不自然 | 颜色像模型本来就打算这样生成——内容自然协调 | + +例子:想要暖橙色调的日落,后处理会给整张图叠橙色(阴影变脏),而 LCS 在采样早期推动颜色,模型生成的云层、光照、反射都与暖色调**内在一致**。 + +论文核心发现:颜色和结构在潜在 patch 空间中是**正交**的,可以单独控制颜色而不干扰结构——在像素空间中无法做到,因为颜色和结构是纠缠在一起的。 + ## 工作原理 1. **投影**:将去噪预测转换到 64D patch 空间,投影到 3D LCS 基底