add karras scheduling variants

modules/sd_samplers.py

@@ -26,6 +26,17 @@ samplers_k_diffusion = [
     ('DPM adaptive', 'sample_dpm_adaptive', ['k_dpm_ad']),
 ]
 
+if opts.show_karras_scheduler_variants:
+    k_diffusion.sampling.sample_dpm_2_ka = k_diffusion.sampling.sample_dpm_2
+    k_diffusion.sampling.sample_dpm_2_ancestral_ka = k_diffusion.sampling.sample_dpm_2_ancestral
+    k_diffusion.sampling.sample_lms_ka = k_diffusion.sampling.sample_lms
+    samplers_k_diffusion_ka = [
+        ('LMS K Scheduling', 'sample_lms_ka', ['k_lms_ka']),
+        ('DPM2 K Scheduling', 'sample_dpm_2_ka', ['k_dpm_2_ka']),
+        ('DPM2 a K Scheduling', 'sample_dpm_2_ancestral_ka', ['k_dpm_2_a_ka']),
+    ]
+    samplers_k_diffusion.extend(samplers_k_diffusion_ka)
+
 samplers_data_k_diffusion = [
     SamplerData(label, lambda model, funcname=funcname: KDiffusionSampler(funcname, model), aliases)
     for label, funcname, aliases in samplers_k_diffusion
@@ -345,6 +356,8 @@ class KDiffusionSampler:
 
         if p.sampler_noise_scheduler_override:
           sigmas = p.sampler_noise_scheduler_override(steps)
+        elif self.funcname.endswith('ka'):
+          sigmas = k_diffusion.sampling.get_sigmas_karras(n=steps, sigma_min=0.1, sigma_max=10, device=shared.device)
         else:
           sigmas = self.model_wrap.get_sigmas(steps)
         x = x * sigmas[0]