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Patched Version of uniform_exposure.py from http://www.magiclantern.fm/forum/index.php?topic=7022.0
# Develop a bunch of raw pics so they look pretty much equally exposed.
# Copyright (2013) a1ex. License: GPL.
# Requires python, numpy, dcraw, ufraw, enfuse and ImageMagick.
# Usage:
# 1) Place your raw photos under a "raw" subdirectory; for example:
#
# $ ls -R
# .:
# uniform-exposure.py
#
# ./raw:
# IMG_0001.CR2 IMG_0002.CR2 ...
#
# 2) run the script
#
# $ python uniform-exposure.py
#
# IMG_0001.CR2:
# midtones: brightness level = 3474 => exposure = +1.53 EV
# highlights: brightness level =29796 => exposure = +0.01 EV
# shadows: brightness level = 1767 => exposure = +3.50 EV
# . . . .
# Developing images... [5% done, ETA 0:05:02]...
#
# 3) the images will be placed in a directory called 'jpg'.
#
# 4) you will also get images optimized for highlights, for midtones and for shadows.
from __future__ import division
# User adjustable parameters
# =====================================================================================
# exposure compensation, in EV
overall_bias = 0
# from 0 to 65535
highlight_level = 50000
midtone_level = 10000
shadow_level = 1000
raw_dir = 'raw'
out_dir = 'jpg'
tmp_dir = 'tmp'
ufraw_options = "--clip=film --saturation=1.3 --temperature=5500 --green=1 --shrink=2"
# for Samyang 8mm on full-frame cameras: don't analyze the black borders
samyang8ff = False
# =====================================================================================
import os, sys, re, time, datetime, subprocess, shlex
from math import *
from numpy import *
direrr = False
try: os.mkdir(out_dir)
except: print "Warning: could not create output dir '%s'" % out_dir
try: os.mkdir(tmp_dir)
except: print "Warning: could not create working dir '%s'" % tmp_dir
def progress(x, interval=1):
global _progress_first_time, _progress_last_time, _progress_message, _progress_interval
try:
p = float(x)
init = False
except:
init = True
if init:
_progress_message = x
_progress_last_time = time.time()
_progress_first_time = time.time()
_progress_interval = interval
elif x:
if time.time() - _progress_last_time > _progress_interval:
print >> sys.stderr, "%s [%d%% done, ETA %s]..." % (_progress_message, int(100*p), datetime.timedelta(seconds = round((1-p)/p*(time.time()-_progress_first_time))))
_progress_last_time = time.time()
def change_ext(file, newext):
return os.path.splitext(file)[0] + newext
def get_raw_data_for_median(file):
cmd1 = "dcraw -c -d -4 -o 0 -h -T '%s'" % file
cmd2 = "convert - -type Grayscale -gravity Center %s -scale 1000x1000 -format %%c histogram:info:-" % ("-crop 67%x67%" if samyang8ff else "")
if 0: # use this to troubleshoot the dcraw conversion
cmd_dbg = cmd1 + " | convert - -type Grayscale -gravity Center -scale 500x500 " + change_ext(file, "-debug.jpg")
print cmd_dbg
os.system(cmd_dbg)
p1 = subprocess.Popen(shlex.split(cmd1), stdout=subprocess.PIPE)
p2 = subprocess.Popen(shlex.split(cmd2), stdin=p1.stdout, stdout=subprocess.PIPE)
lines = p2.communicate()[0].split("\n")
X = []
for l in lines[1:]:
p1 = l.find("(")
if p1 > 0:
p2 = l.find(",", p1)
level = int(l[p1+1:p2])
count = int(l[:p1-2])
X += [level]*count
return array(X)
def get_medians(file):
X = get_raw_data_for_median(file)
# for midtones
m = median(X)
mm = float(m)
# for highlights
m = median(X) # 50%
m = median(X[X > m]) # 75%
m = median(X[X > m]) # 87.5%
m = median(X[X > m]) # 93.75%
m = median(X[X > m]) # 96.875%
m = median(X[X > m]) # 98.4375%
m = median(X[X > m])
m = median(X[X > m])
m = median(X[X > m])
m = median(X[X > m])
mh = float(m) if isfinite(m) else float(max(X))
# for shadows
m = median(X) # 50%
m = median(X[X < m]) # 25%
m = median(X[X < m]) # 12.5%
m = median(X[X < m]) # 6.25
ms = float(m) if isfinite(m) else float(min(X))
if 0: # use this to troubleshoot the medians
cmd1 = "dcraw -c -d -4 -o 0 -h -T '%s'" % file
cmd_dbg = cmd1 + " | convert - -type Grayscale -gravity Center -threshold %g '%s' " % (mm-1, change_ext(file, "-midtones.jpg"))
os.system(cmd_dbg)
cmd_dbg = cmd1 + " | convert - -type Grayscale -gravity Center -threshold %g '%s' " % (ms-1, change_ext(file, "-shadows.jpg"))
os.system(cmd_dbg)
cmd_dbg = cmd1 + " | convert - -type Grayscale -gravity Center -threshold %g '%s' " % (mh-1, change_ext(file, "-highlights.jpg"))
os.system(cmd_dbg)
return mm, mh, ms
def expo_range(start, end, step):
step = abs(step) * sign(end-start)
r = arange(start, end+0.5*sign(step), step)
if len(r) <= 1:
return [end]
step = float(end-start) / (len(r)-1)
r = arange(start, end+0.5*sign(step), step)
return r[1:]
files = sorted(os.listdir(raw_dir))
# prefer the DNG if there are two files with the same name
for f in [f for f in files]:
dng = change_ext(f, ".DNG")
if f[0] == ".":
files.remove(f)
continue
if dng != f and dng in files:
files.remove(f)
progress("")
for k,f in enumerate(files):
r = os.path.join(raw_dir, f)
j = os.path.join(out_dir, change_ext(f, ".jpg"))
jm = os.path.join(tmp_dir, change_ext(f, "-m.jpg"))
jh = os.path.join(tmp_dir, change_ext(f, "-h.jpg"))
js = os.path.join(tmp_dir, change_ext(f, "-s.jpg"))
# don't overwrite existing jpeg files
if os.path.isfile(j) or os.path.isfile(change_ext(j, "r.jpg")):
print "%s: output file %s already exists, skipping" % (r, j)
continue
# skip sub-dirs under raw_dir
if not os.path.isfile(r):
continue
if f.lower().endswith('.jpg'):
continue
print ""
print "%s:" % r
try: mm, mh, ms = get_medians(r)
except: continue
# normal exposure
ecm = -log2(mm / midtone_level) + overall_bias
# exposure for highlights
ech = max(-log2(mh / highlight_level) + overall_bias, 0)
needs_highlight_recovery = (ech < ecm - 0.5);
# exposure for shadows
ecs = -log2(ms / shadow_level) + overall_bias
needs_shadow_recovery = (ecs > ecm + 0.5)
# compensate normal exposure to avoid brightness changes when doing strong recovery (approximate)
if needs_highlight_recovery: ecm += 0.25 * abs(ech - ecm)
if needs_shadow_recovery: ecm -= 0.25 * abs(ecs - ecm)
# do highlight/shadow recovery in more steps, not just one
if needs_highlight_recovery: ech = expo_range(ecm, ech, 1)
else: ech = [ech]
if needs_shadow_recovery: ecs = expo_range(ecm, ecs, 1)
else: ecs = [ecs]
# print the levels
print " midtones: brightness level %5d => exposure %+.2f EV" % (mm, ecm)
print " highlights: brightness level %5d => exposure %s EV %s" % (mh, ",".join(["%+.2f" % e for e in ech]), "" if needs_highlight_recovery else "(skipping)")
print " shadows: brightness level %5d => exposure %s EV %s" % (ms, ",".join(["%+.2f" % e for e in ecs]), "" if needs_shadow_recovery else "(skipping)")
print "", ; sys.stdout.flush()
# develop the raws
jpegs = [jm]
print "(midtones)", ; sys.stdout.flush()
cmd = "ufraw-batch --out-type=jpg --overwrite %s --exposure=%s '%s' --output='%s' 2>> dev.log" % (ufraw_options, ecm, r, jm)
os.system(cmd)
if needs_highlight_recovery:
# highlight recovery
print "(highlights", ; sys.stdout.flush()
for ji,e in enumerate(ech):
if ji > 0: print "\b.", ; sys.stdout.flush()
jp = change_ext(jh, "%d.jpg" % ji)
cmd = "ufraw-batch --out-type=jpg --overwrite %s --exposure=%s '%s' --output='%s' 2>> dev.log" % (ufraw_options, e, r, jp)
os.system(cmd)
jpegs.append(jp)
print "\b)", ; sys.stdout.flush()
if needs_shadow_recovery:
# shadow recovery
print "(shadows", ; sys.stdout.flush()
for ji,e in enumerate(ecs):
if ji > 0: print "\b.", ; sys.stdout.flush()
jp = change_ext(js, "%d.jpg" % ji)
cmd = "ufraw-batch --out-type=jpg --overwrite %s --exposure=%s '%s' --output='%s' 2>> dev.log" % (ufraw_options, e, r, jp)
os.system(cmd)
jpegs.append(jp)
print "\b)", ; sys.stdout.flush()
if needs_highlight_recovery or needs_shadow_recovery:
# blend highlights and shadows
print "(enfuse)", ; sys.stdout.flush()
cmd = "enfuse %s -o '%s' 2>> dev.log" % (" ".join(["'%s'" % ji for ji in jpegs]), j)
os.system(cmd)
else:
# nothing to blend
print "(copy)", ; sys.stdout.flush()
cmd = "cp '%s' '%s'" % (jm, j)
os.system(cmd)
cmd = "echo \"%s: overall_bias=%g; highlight_level=%g; midtone_level=%g; shadow_level=%g; ufraw_options='%s'; \" >> settings.log" % (f, overall_bias, highlight_level, midtone_level, shadow_level, ufraw_options)
os.system(cmd)
if 0:
# lossless optimization of the Huffman tables
cmd = "jpegoptim '%s'" % j
os.system(cmd)
# copy over exif-data (without old preview/thumbnail-images and without orientation as ufraw already takes care of it) and add comment with processing parameters
comment = "overall_bias=%g; highlight_level=%g; midtone_level=%g; shadow_level=%g; ufraw_options='%s'; " % (overall_bias, highlight_level, midtone_level, shadow_level, ufraw_options)
comment += "midtones: brightness level %5d => exposure %+.2f EV; " % (mm, ecm)
comment += "highlights: brightness level %5d => exposure %s EV %s; " % (mh, ",".join(["%+.2f" % e for e in ech]), "" if needs_highlight_recovery else "(skipping)")
comment += "shadows: brightness level %5d => exposure %s EV %s" % (ms, ",".join(["%+.2f" % e for e in ecs]), "" if needs_shadow_recovery else "(skipping)")
cmd = "exiftool -TagsFromFile '%s' -comment=%s -ThumbnailImage= -PreviewImage= -Orientation= -z -overwrite_original '%s'" % (r, '"%s"' % comment, j)
os.system(cmd)
print ""
progress((k+1) / len(files))
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