unipc sampling

**UniPC sampling** is the **unified predictor-corrector sampling framework that achieves high-order diffusion integration with broad model compatibility** - it is designed to deliver strong quality in low-step regimes. **What Is UniPC sampling?** - **Definition**: Combines coordinated predictor and corrector formulas within a shared update framework. - **Order Control**: Supports configurable integration order for speed-quality balancing. - **Model Coverage**: Applicable to many pretrained diffusion checkpoints with minimal retraining needs. - **Guidance Handling**: Built to remain stable under classifier-free guidance settings. **Why UniPC sampling Matters** - **Few-Step Strength**: Produces competitive quality at aggressive low step counts. - **Operational Flexibility**: Single framework simplifies sampler management across deployments. - **Quality Consistency**: Predictor-corrector coupling can reduce drift in challenging prompts. - **Ecosystem Relevance**: Frequently benchmarked in modern diffusion optimization stacks. - **Config Complexity**: Order and warmup choices require benchmarking for each model. **How It Is Used in Practice** - **Order Tuning**: Start with recommended defaults, then test higher order only when stable. - **Warmup Strategy**: Use early-step warmup settings that match checkpoint characteristics. - **Benchmark Discipline**: Compare against DPM-Solver and Heun using fixed prompt suites. UniPC sampling is **an advanced low-step sampler for modern diffusion acceleration** - UniPC sampling is most effective when order selection and schedule tuning are validated together.