Underwater picture correction with the GIMP

UnderwaterCorrection.py

# This script can be used to correct red absorption
# when taking pictures underwater
# to use in the GIMP, open the python-fu console,
# set the my_dir variable and exec the file :
# exec(open('path/to/file.py).read())
# Realeased under the WTF public license
for file in listdir(my_dir):
	if (file[-4:] != '.JPG'):
		continue
	print my_dir+'\\'+file
	image = pdb.gimp_file_load(my_dir+'\\'+file,file)
	display = pdb.gimp_display_new(image)
	#Finding the almost-max value for red pixels (99% of pixels have a red value less than that). Stupid, brute force method.
	percentile = 0
	quasi_max = 1
	while percentile < .999:
		quasi_max += 1
		mean, std_dev, median, pixels, count, percentile = pdb.gimp_histogram(image.layers[0], 1, 0, quasi_max)
		#print 'quasi max, percentile'+str(quasi_max)+', '+str(percentile)
	print '\tquasi_max is '+str(quasi_max)
	#Adjusting the values in order to have a full histogram
	new_curve = [min(255,int(i/float(quasi_max)*255.)) for i in range(0,256)]
	pdb.gimp_curves_explicit(image.layers[0], 1, 256, new_curve)
	pdb.gimp_file_save(image, image.layers[0], my_dir+'\\Filtered\\'+file,file)
	pdb.gimp_display_delete(display)