uniform_exposure.py multiprocessing version

uniform_exposure.py

# Develop a bunch of raw pics so they look pretty much equally exposed.
# Copyright (2013) a1ex. License: GPL.

# Requires python, ufraw, enfuse, ImageMagick and exiftool.

# 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  2160 => exposure +4.14 EV
#           highlights: brightness level 58877 => exposure +3.21,+2.28,+1.36,+0.43,-0.50 EV 
#              shadows: brightness level   289 => exposure +2.79 EV (skipping)
#           . . . .
#          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 
# =====================================================================================

# Global options
raw_dir = 'raw'                                     # place raw files here
out_dir = 'jpg'                                     # output files will be saved here
tmp_dir = 'tmp'                                     # temporary working folder
output_tif16bit = False                             # enable to output 16-bit tif

# Options that can be changed for each picture (in override_settings)
overall_bias = 0                                    # exposure compensation, in EV
highlight_level = 20000                             # decrease for stronger highlight recovery
midtone_level = 20000                               # median exposure
shadow_level = 5000                                 # increase for stronger shadow recovery
ev_step = 1                                         # EV step size for bracketed exposures (larger values may cause halos, smaller values are very slow)
target_median = None                                # for the final output (set to None for disabling, try around 128 for flicker-free video/timelapse)
samyang8ff = False                                  # for Samyang 8mm on full-frame cameras: don't analyze the black borders
fullsize = False                                    # develop full size (turn off for higher speed)
ufraw_options = "--temperature=5500 --green=1 "     # customize ufraw parameters (tip: you can also open a file in ufraw, tweak settings in the GUI and save an ID file)
enfuse_options = "--gray-projector=value"           # customize enfuse parameters (tip: tweak --exposure-sigma to adjust contrast and highlight recovery behavior)

def override_settings(fname, num):
    global ufraw_options, default_ufraw_options, overall_bias, default_overall_bias, highlight_level, default_highlight_level, midtone_level, default_midtone_level, shadow_level, default_shadow_level, samyang8ff, default_samyang8ff, fullsize, default_fullsize, target_median, default_target_median, ev_step, default_ev_step, enfuse_options, default_enfuse_options
    try:    ufraw_options = default_ufraw_options; overall_bias = default_overall_bias; highlight_level = default_highlight_level; midtone_level = default_midtone_level; shadow_level = default_shadow_level; samyang8ff = default_samyang8ff; fullsize = default_fullsize; target_median = default_target_median; ev_step = default_ev_step; enfuse_options = default_enfuse_options;
    except: default_ufraw_options = ufraw_options; default_overall_bias = overall_bias; default_highlight_level = highlight_level; default_midtone_level = midtone_level; default_shadow_level = shadow_level; default_samyang8ff = samyang8ff; default_fullsize = fullsize; default_target_median = target_median; default_ev_step = ev_step; default_enfuse_options = enfuse_options;

    # override per-picture settings here
    # for example:
    #
    # if num in range(1234, 1251):
    #       overall_bias += 2
    

# =====================================================================================

import os, sys, re, time, datetime, subprocess, shlex, shutil
from multiprocessing import Pool
from math import *

os.putenv("OMP_NUM_THREADS", "1") # optimizes the parallelisation, by allowing only one OpenMP thread per shell programm

log2 = lambda x: log(x) / log(2)
sign = lambda x: x / abs(x) if x != 0 else 0

direrr = False

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 run(cmd):
    try:
        p = subprocess.Popen(cmd, shell=True, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
        out = p.communicate()
        if p.returncode:
            print cmd
            print out[0]
            print out[1]
            raise SystemExit
            
        f = open("dev.log", "a");
        print >> f, cmd
        print >> f, out[0]
        print >> f, out[1]
        print >> f, ""
        f.close()
        return out[0]
    except KeyboardInterrupt:
        raise SystemExit
    except SystemExit:
        raise SystemExit
    except:
        print sys.exc_info()

def change_ext(file, newext):
    return os.path.splitext(file)[0] + newext

def file_number(j):
    nr = re.search("([0-9][0-9][0-9][0-9]+)", j)
    if nr:
        nr = int(nr.groups()[0])
        return nr

def get_histogram_data_work(file, cmd):

    try: 
        p = subprocess.Popen(cmd, shell=True, stdout=subprocess.PIPE)
        out = p.communicate()
        if p.returncode:
            print out[0]
            raise SystemExit
        
        lines = out[0].split("\n")

    except KeyboardInterrupt:
        raise SystemExit

    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.append((level, count))
    return X

def get_histogram_data_for_raw(file):
    cmd1 = 'ufraw-batch --exposure=0 --gamma=1 --clip=digital --shrink=10 --grayscale=luminance --out-depth=16 --output=- --create-id=no --silent "%s"' % file
    cmd2 = "convert - -gravity Center %s -format %%c histogram:info:-" % ("-crop 67%x67%" if samyang8ff else "")
    cmd = cmd1 + " | " + cmd2
    return get_histogram_data_work(file, cmd)

def get_histogram_data_for_jpg(file):
    cmd = 'convert "%s" -gravity Center %s -format %%c histogram:info:-' % (file, "-crop 67%x67%" if samyang8ff else "")
    return get_histogram_data_work(file, cmd)

def get_histogram_data(file):
    ext = os.path.splitext(file)[1].lower()
    if ext in [".cr2", ".dng", ".ufraw"]:
        return get_histogram_data_for_raw(file)
    else:
        return get_histogram_data_for_jpg(file)

def get_percentiles(file, percentiles):
    X = get_histogram_data(file)
    
    ans = []
    for percentile in percentiles:
    
        total = sum([count for level, count in X])
        target = total * percentile / 100
        
        acc = 0
        for level, count in X:
            acc += count
            if acc >= target:
                ans.append(level)
                break

    # see where these percentile levels fall on the image
    # (where exactly it meters to keep the exposure constant)
    if 0:
        level_min = min(ans)
        level_max = max(ans)
        cmd1 = 'ufraw-batch --exposure=0 --gamma=1 --clip=digital --shrink=10 --grayscale=luminance --out-depth=16 --output=- --silent "%s"' % file
        cmd_dbg = cmd1 + ' | convert - -gravity Center -level %s,%s -solarize 65534 -threshold 0 "%s" ' % (level_min-1, level_max+1, change_ext(file, "-test.jpg"))
        print cmd_dbg
        run(cmd_dbg)

    return ans

def get_medians(file):
    return get_percentiles(file, [50, 99.99, 1])

def frange(x, y, jump):
    if jump > 0:
        while x < y:
            yield x
            x += jump
    else:
        while x > y:
            yield x
            x += jump
    

def expo_range(start, end, step):
    step = abs(step) * sign(end-start)
    r = list(frange(start, end+0.5*sign(step), step))
    if len(r) <= 1:
        return [end]
    step = float(end-start) / (len(r)-1)
    r = list(frange(start, end+0.5*sign(step), step))
    return r[1:]

def parse_lev(lev):
    roll = 0
    pitch = 0
    lines = open(lev).readlines()
    for l in lines:
        m = re.match("Roll *: *([+\-0-9.]+)", l)
        if m:
            try: roll = float(m.groups()[0])
            except: pass
        m = re.match("Pitch *: *([+\-0-9.]+)", l)
        if m:
            try: pitch = float(m.groups()[0])
            except: pass
    return roll, pitch

def gamma_correction(file, target_median):
    median = get_percentiles(file, [50])[0]
    median = median / 255
    target_median = target_median / 255
    if median >= 1:
        return
    gamma = log2(median) / log2(target_median)
    line = ("(gamma %.02f)" % gamma)
    cmd = 'mogrify -gamma %f "%s" ' % (gamma, file)
    run(cmd)
    return line

def main(f):
    global ufraw_options, default_ufraw_options, overall_bias, default_overall_bias, highlight_level, default_highlight_level, midtone_level, default_midtone_level, shadow_level, default_shadow_level, samyang8ff, default_samyang8ff, fullsize, default_fullsize, target_median, default_target_median, ev_step, default_ev_step, enfuse_options, default_enfuse_options
    r  = os.path.join(raw_dir, f)
    j  = os.path.join(out_dir, change_ext(f, ".tif" if output_tif16bit else ".jpg"))
    jm = os.path.join(tmp_dir, change_ext(f, "-m.tif"))
    jh = os.path.join(tmp_dir, change_ext(f, "-h.tif"))
    js = os.path.join(tmp_dir, change_ext(f, "-s.tif"))
    ufr = change_ext(r, ".ufraw")
    lev = change_ext(r, ".LEV")

    # don't overwrite existing jpeg files
    if os.path.isfile(j) or os.path.isfile(change_ext(j, "r.jpg")):
        return "%s: output file %s already exists, skipping\n" % (r, j), None

    # skip sub-dirs under raw_dir
    if not os.path.isfile(r):
        return None, None
    
    if f.lower().endswith('.jpg'):
        return None, None

    rotate_options = ""
    if os.path.isfile(lev):
        roll, pitch = parse_lev(lev)
        r90 = round(roll/90.0) * 90
        roll -= r90
        ar = "2:3" if abs(r90) == 90 else "3:2"
        rotate_options = " --rotate=%s --auto-crop --aspect-ratio %s " % (-roll, ar)

    lines = ""
    lines += "%s:\n" % r

    # override settings
    override_settings(r, file_number(r))
    ufraw_options = rotate_options + ufraw_options
    lines += ufraw_options + "\n"

    # compute percentiles
    mm, mh, ms = get_medians(r)

    # normal exposure
    ecm = -log2(mm / midtone_level) + overall_bias

    # exposure for highlights
    ech = max(-log2(mh / highlight_level) + overall_bias, -0.5)
    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, ev_step)
    else: ech = [ech]
    if needs_shadow_recovery: ecs = expo_range(ecm, ecs, ev_step)
    else: ecs = [ecs]

    # print the levels
    lines += "    midtones: brightness level %5d => exposure %+.2f EV\n" % (mm, ecm)
    lines += "  highlights: brightness level %5d => exposure %s EV %s\n" % (mh, ",".join(["%+.2f" % e for e in ech]), "" if needs_highlight_recovery else "(skipping)")
    lines += "     shadows: brightness level %5d => exposure %s EV %s\n" % (ms, ",".join(["%+.2f" % e for e in ecs]), "" if needs_shadow_recovery else "(skipping)")
    lines += ""

    # any ufraw settings file? use it when developing
    if os.path.isfile(ufr):
        r = ufr

    # develop the raws
    shrink = 1 if fullsize == True else (2 if fullsize == False else fullsize)
    jpegs = [jm]
    lines += "(midtones)"
    cmd = 'ufraw-batch --out-type=tiff --out-depth=16 --overwrite %s --exposure=%s "%s" --output="%s" --shrink=%d' % (ufraw_options, ecm, r, jm, shrink)
    run(cmd)
    
    if needs_highlight_recovery:
        # highlight recovery
        lines += "(highlights"
        for ji,e in enumerate(ech):
            if ji > 0: lines += "\b."
            jp = change_ext(jh, "%d.tif" % ji)
            cmd = 'ufraw-batch --out-type=tiff --out-depth=16 --overwrite %s --exposure=%s "%s" --output="%s" --shrink=%d' % (ufraw_options, e, r, jp, shrink)
            run(cmd)
            jpegs.append(jp)
        lines += "\b)"

    if needs_shadow_recovery:
        # shadow recovery
        lines += "(shadows"
        for ji,e in enumerate(ecs):
            if ji > 0: lines += "\b."
            jp = change_ext(js, "%d.tif" % ji)
            cmd = 'ufraw-batch --out-type=tiff --out-depth=16 --overwrite %s --exposure=%s "%s" --output="%s" --shrink=%d' % (ufraw_options, e, r, jp, shrink)
            run(cmd)
            jpegs.append(jp)
        lines += "\b)"

    if needs_highlight_recovery or needs_shadow_recovery:
        # blend highlights and shadows
        lines += "(enfuse)"
        compression = "--compression=DEFLATE" if output_tif16bit else ""
        cmd = 'enfuse %s %s -o "%s" %s' % (enfuse_options, compression, j, " ".join(['"%s"' % ji for ji in jpegs]))
        run(cmd)
    else:
        # nothing to blend
        if output_tif16bit:
            lines += "(copy)"
            shutil.copy(jm, j)
        else:
            lines += "(convert)"
            run("convert %s %s" % (jm, j))
    
    if target_median:
        lines += gamma_correction(j, target_median)
    
    settings_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)

    if 0:
        # lossless optimization of the Huffman tables
        cmd = 'jpegoptim "%s"' % j
        run(cmd)
    
    if 1:
        # copy over exif-data (without old preview/thumbnail-images and without orientation/icc-profile as ufraw already takes care of it), setting colorspace to sRGB 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= -icc_profile:all= -all:Colorspace=sRGB -z -overwrite_original "%s"' % (r, comment, j)
        run(cmd)
    
    if 1:
        # cleanup temporary files
        for j in jpegs:
            os.remove(j)

    lines += "\n"
    return lines, settings_cmd

if __name__ == '__main__':
    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

    progress("")
    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)
            continue
        
        # only process CR2 and DNG
        if not(f.endswith(".CR2") or f.endswith(".cr2") or f.endswith(".DNG") or f.endswith(".dng")):
            files.remove(f)
            continue

    p = Pool()
    it = p.imap(main, files)
    for k,f in enumerate(files):
        line, settings_cmd = it.next()
        if line: 
            print line
        if settings_cmd: 
            run(settings_cmd)
        progress((k+1) / len(files))
    p.close()