add OIDN firefly suppression option

export/aovs.py

@@ -257,6 +257,8 @@ def get_OIDN_props(definitions, scene, index):
     definitions[str(index) + ".oidnmemory"] = denoiser.max_memory_MB
     definitions[str(index) + ".sharpness"] = 0
     definitions[str(index) + ".prefilter.enable"] = denoiser.prefilter_AOVs
+    if denoiser.oidn_firefly_suppression:
+        definitions[str(index) + ".firefly.sigma"] = denoiser.oidn_firefly_sigma
     return index + 1
 
 

properties/denoiser.py

@@ -61,3 +61,12 @@ class LuxCoreDenoiser(PropertyGroup):
                                                   default="REFLECT_TRANSMIT", description="How to treat specular materials in the albedo AOV")
     prefilter_AOVs: BoolProperty(name="Prefilter Auxiliary AOVs", default=True,
                                  description="Denoise the albedo and avg. shading normal AOVs before using them to denoise the main image")
+    oidn_firefly_suppression: BoolProperty(name="Firefly Suppression", default=False,
+                                           description="Scale down isolated outlier pixels before denoising, so the "
+                                                       "denoiser does not smear fireflies into blobs. Only the denoised "
+                                                       "result is affected, the raw render is untouched. Intended for "
+                                                       "mostly converged renders: at very low sample counts the noise "
+                                                       "is the signal and suppressing it darkens the image")
+    oidn_firefly_sigma: FloatProperty(name="Threshold", default=4.0, min=1.0, soft_max=10.0,
+                                      description="Outlier threshold in units of local noise (median absolute "
+                                                  "deviation). Lower values suppress more aggressively")

ui/render/denoiser.py

@@ -60,6 +60,11 @@ def draw(self, context):
             sub.prop(denoiser, "max_memory_MB")
             sub.prop(denoiser, "albedo_specular_passthrough_mode")
             sub.prop(denoiser, "prefilter_AOVs")
+            row = layout.row()
+            row.prop(denoiser, "oidn_firefly_suppression")
+            sub = row.row()
+            sub.active = denoiser.oidn_firefly_suppression
+            sub.prop(denoiser, "oidn_firefly_sigma")
 
 
 class LUXCORE_RENDER_PT_denoiser_bcd_advanced(RenderButtonsPanel, Panel):