Firefly removal in blender

This is a continuation of the previous post about Adjusting image pixels internally in Blender with bpy

firefly removal

In optimal lighting conditions fireflies don't really occur often in cycles, I can't remember seeing any lately. here's a script that first creates a simulation of fireflies then removes them.

	import bpy
	import random
	D = bpy.data
	image_name = 'pixeltest4'
	if not image_name in D.images:
	image_object = D.images.new(name=image_name, width=40, height=30)
	image_object = D.images[image_name]
	num_pixels = len(image_object.pixels)
	""" set default values """
	dm = [.2, .2, .2, 1.0] * (int(num_pixels/4))
	""" randomize background noise """
	for i in range(0,len(dm),4):
	# only affect RGB, not A. Never full white.
	for j in range(3):
	dm[i+j] = (random.random()*.5)
	""" insert fireflies at random """
	last_pixel = False
	for i in range(0,len(dm),4):
	rand_val = random.random()
	if rand_val > .97 and not last_pixel:
	last_pixel = True
	for j in range(3):
	dm[i+j] = (1.0)
	else:
	last_pixel = False
	""" assign list to pixels """
	image_object.pixels = dm

view raw firefly_removal.py hosted with ❤ by GitHub

results in this:

TBC

As you can see it's probably an ok simulation, looking at it tells me something about a potential algorithm.

• collect all whites
• sample colour from the surrounding non white pixels

Most images don't have any pixels that are fully white, so i won't include a check for all surrounding pixels.

Finished firefly removal script can be found here: link