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The BasicScheduler node is designed to compute a sequence of sigma values for diffusion models based on the provided scheduler, model, and denoising parameters. It dynamically adjusts the total number of steps based on the denoise factor to fine-tune the diffusion process, providing precise “recipes” for different stages in advanced sampling processes that require fine control (such as multi-stage sampling).

Inputs

ParameterMetaphor DescriptionData TypeInput TypeDefaultRangeTechnical Purpose
modelCanvas Type: Different canvas materials need different paint formulasMODELInput--Diffusion model object, determines sigma calculation basis
schedulerMixing Technique: Choose how paint concentration changesCOMBO[STRING]Widget-9 optionsScheduling algorithm, controls noise decay mode
stepsMixing Count: 20 mixes vs 50 mixes precision differenceINTWidget201-10000Sampling steps, affects generation quality and speed
denoiseCreation Intensity: Control level from fine-tuning to repaintingFLOATWidget1.00.0-1.0Denoising strength, supports partial repainting scenarios

Scheduler Types

Based on source code comfy.samplers.SCHEDULER_NAMES, supports the following 9 schedulers:
Scheduler NameCharacteristicsUse CasesNoise Decay Pattern
normalStandard linearGeneral scenarios, balancedUniform decay
karrasSmooth transitionHigh quality, detail-richSmooth non-linear decay
exponentialExponential decayFast generation, efficiencyExponential rapid decay
sgm_uniformSGM uniformSpecific model optimizationSGM optimized decay
simpleSimple schedulingQuick testing, basic useSimplified decay
ddim_uniformDDIM uniformDDIM sampling optimizationDDIM specific decay
betaBeta distributionSpecial distribution needsBeta function decay
linear_quadraticLinear quadraticComplex scenario optimizationQuadratic function decay
kl_optimalKL optimalTheoretical optimizationKL divergence optimized decay

Outputs

ParameterMetaphor DescriptionData TypeOutput TypeTechnical Meaning
sigmasPaint Recipe Chart: Detailed paint concentration list for step-by-step useSIGMASOutputNoise level sequence, guides diffusion model denoising process

Node Role: Artist’s Color Mixing Assistant

Imagine you are an artist creating a clear image from a chaotic mixture of paint (noise). BasicScheduler acts like your professional color mixing assistant, whose job is to prepare a series of precise paint concentration recipes:

Workflow

  • Step 1: Use 90% concentration paint (high noise level)
  • Step 2: Use 80% concentration paint
  • Step 3: Use 70% concentration paint
  • Final Step: Use 0% concentration (clean canvas, no noise)

Color Assistant’s Special Skills

Different mixing methods (scheduler):
  • “karras” mixing method: Paint concentration changes very smoothly, like professional artist’s gradient technique
  • “exponential” mixing method: Paint concentration decreases rapidly, suitable for quick creation
  • “linear” mixing method: Paint concentration decreases uniformly, stable and controllable
Fine control (steps):
  • 20 mixes: Quick painting, efficiency priority
  • 50 mixes: Fine painting, quality priority
Creation intensity (denoise):
  • 1.0 = Complete new creation: Start completely from blank canvas
  • 0.5 = Half transformation: Keep half of original painting, transform half
  • 0.2 = Fine adjustment: Only make subtle adjustments to original painting

Collaboration with Other Nodes

BasicScheduler (Color Assistant) → Prepare Recipe → SamplerCustom (Artist) → Actual Painting → Completed Work
This documentation was AI-generated. If you find any errors or have suggestions for improvement, please feel free to contribute! Edit on GitHub