Article Outline
Python pil example 'shrink'
Functions in program:
def getGoodThreadValue():
Modules used in program:
import BmpImagePlugin, GifImagePlugin, JpegImagePlugin, PngImagePluginimport multiprocessing, os, PIL, Queue, shutil, string, sys, threading
python shrink
Python pil example: shrink
"""
Author: Matze
Date: July 2012
Website: https://github.com/ma4a
About functions:
*creates same recursive folder structure in parallel with resized images
*you have two folder structures. the first untouched one with the source files and the one with resized images and copied videos
*resize any found image that's larger than needed -> EXIF data not copied
*just copy any image that's smaller than needed - no resize necessary -> EXIF data may be copied
*copy any video without doing anything with the file
*file types that are not defined as video or image are simply skipped
*supports threading per folder to speed up. i.e. using 6 threads on a quad core was more than 6 times faster than without :)
*summary at the end to see success or failure
Requirements:
*PIL (tested with 1.1.7, http://www.pythonware.com/products/pil/)
*Python (according to PIL, tested with 2.7.3 for Win 32bit, http://www.python.org/download/)
"""
import multiprocessing, os, PIL, Queue, shutil, string, sys, threading
from PIL import Image, ImageOps
import BmpImagePlugin, GifImagePlugin, JpegImagePlugin, PngImagePlugin
#* * * don't touch this * * *#
def getGoodThreadValue():
if multiprocessing.cpu_count() > 1:
return 2 * multiprocessing.cpu_count() - 2
else:
return 1
#SETTINGS *** only change values in this area
dirBig = 'D:\_shrinked\img' #source folder, absolute path
dirSmall = 'D:\_shrinked\img_small' #destination folder, absolute path
extList_img = [".jpg", ".jpeg", ".png", ".gif"] #image file extensions
extList_vid = [".mp4", ".3gp", ".mov", ".avi", ".mpg", ".mpeg"] #video file extensions
newSize = (0,800) #set the dimensions for destination image. set one dimension to 0!
imgQuality = 80 #quality of new image
logOnly = False #enable or disable logging to file. disables normal output to screen
skipExisting = False #if file exists already, just skip
debug = False #activate to get some help for error search
numberOfThreads = getGoodThreadValue() #algo to choose a good number of threads. you can also replace it by any number but 2*core-2 seems to be best working
#end of SETTINGS *** only change values in the area above
#* * * don't touch below * * *#
directory = os.path.abspath(".") #absolute path to current directory
if logOnly: sys.stdout = open(directory + '\\log.txt', 'a')
count_img = 0
count_vid = 0
count_skip = 0
count_error = 0
class work4me(threading.Thread):
wresult = {}
wlock = threading.Lock()
wqueue = Queue.Queue(maxsize=-1)
plock = threading.Lock()
def run(self):
while True:
args = work4me.wqueue.get()
r = self.shrink(args)
work4me.wlock.acquire()
work4me.wresult[args] = r
work4me.wlock.release()
work4me.wqueue.task_done()
def shrink(self, args):
global count_img
global count_vid
global count_skip
global count_error
#split args
dir_from = args[0]
dir_to = args[1]
file = args[2]
file_from = dir_from + "\\" + file
file_to = dir_to + "\\" + file
if not os.access(file_to, os.F_OK) or not skipExisting:
if string.lower(os.path.splitext(file)[1]) in extList_img: #image
try:
img_in = Image.open(file_from)
except IOError:
work4me.plock.acquire()
print("[ERROR]", file, "threw error 'cannot identify image'")
count_error+=1
work4me.plock.release()
return "error"
if (img_in.size[0]<10000 and img_in.size[1]<10000):
if (int(newSize[0])==0): #resize to a defined height
if (img_in.size[1]<=newSize[1]):
if not os.access(file_to, os.F_OK) or not skipExisting:
shutil.copyfile(file_from, file_to)
work4me.plock.acquire()
print("[IMG] ", file, "already small enough. just copied")
count_img+=1
work4me.plock.release()
else:
newSize_do = int((float(newSize[1])/img_in.size[1])*img_in.size[0]) , int(newSize[1])
img_out = ImageOps.fit(img_in, newSize_do, Image.ANTIALIAS)
img_out.save(file_to, quality=int(imgQuality))
work4me.plock.acquire()
print("[IMG] ", file, "|", img_in.size, "->", newSize_do)
count_img+=1
work4me.plock.release()
elif (int(newSize[1])==0): #resize to a defined width
if (img_in.size[0]<=newSize[0]):
if not os.access(file_to, os.F_OK) or not skipExisting:
shutil.copyfile(file_from, file_to)
work4me.plock.acquire()
print("[IMG] ", file, "already small enough. just copied")
count_img+=1
work4me.plock.release()
else:
newSize_do = int(newSize[0]), int((float(newSize[0])/img_in.size[0])*img_in.size[1])
img_out = ImageOps.fit(img_in, newSize_do, Image.ANTIALIAS)
img_out.save(file_to, quality=int(imgQuality))
work4me.plock.acquire()
print("[IMG] ", file, "|", img_in.size, "->", newSize_do)
count_img+=1
work4me.plock.release()
else:
work4me.plock.acquire()
print("Error on resize! Wrong dimensions in 'newSize' setting!")
work4me.plock.release()
raw_input("Press Enter to exit...")
sys.exit(1)
else:
work4me.plock.acquire()
print("[ERROR]", file, "too large", img_in.size)
count_error+=1
work4me.plock.release()
if (debug and not logOnly): raw_input("Press Enter to continue...")
elif string.lower(os.path.splitext(file)[1]) in extList_vid: #video
if not os.access(file_to, os.F_OK) or not skipExisting:
shutil.copyfile(file_from, file_to)
work4me.plock.acquire()
print("[VID] ", file, "just copied")
count_vid+=1
work4me.plock.release()
else: #something to skip/don't do anything
work4me.plock.acquire()
print("[SKIP] ", file)
count_skip+=1
work4me.plock.release()
else:
work4me.plock.acquire()
print("[SKIP] ", file, "already exists" #skip file if option is set and file already exists)
count_skip+=1
work4me.plock.release()
return "done"
myThreads = [work4me() for i in range(numberOfThreads)]
for t in myThreads:
t.setDaemon(True)
t.start()
for folder, subfolders, files in os.walk(dirBig):
dir_from = os.path.abspath(folder)
dir_to = os.path.abspath(folder.replace(dirBig, dirSmall))
if not os.access(dir_to, os.F_OK):
os.mkdir(dir_to) #create folder if it doesn't exist
print("[MKDIR]", dir_to)
print("[CHDIR]", dir_to)
myThreads = [work4me() for i in range(numberOfThreads)]
for file in files:
args = (dir_from, dir_to, file)
work4me.wresult[args] = "working"
work4me.wqueue.put(args)
work4me.wqueue.join()
with work4me.wqueue.mutex: work4me.wqueue.queue.clear()
work4me.wresult = {}
if (debug and not logOnly): raw_input("Press Enter to continue...")
print("\n\nSummary:")
print("[IMG] ", count_img)
print("[VID] ", count_vid)
print("[SKIP] ", count_skip)
print("[ERROR]", count_error)
if logOnly: sys.stdout.close()
if (not logOnly): raw_input("Press Enter to exit...")
Python links
- Learn Python: https://pythonbasics.org/
- Python Tutorial: https://pythonprogramminglanguage.com