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iOS PNG uncrushers based on http://www.axelbrz.com.ar/?mod=iphone-png-images-normalizer with a fix for multiple IDAT
#---
# iPIN - iPhone PNG Images Normalizer v1.0
# Copyright (C) 2007
#
# Author:
# Axel E. Brzostowski
# http://www.axelbrz.com.ar/
# axelbrz@gmail.com
#
# References:
# http://iphone.fiveforty.net/wiki/index.php/PNG_Images
# http://www.libpng.org/pub/png/spec/1.2/PNG-Contents.html
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
#---
from struct import *
from zlib import *
import stat
import sys
import os
def getNormalizedPNG(filename):
pngheader = "\x89PNG\r\n\x1a\n"
file = open(filename, "rb")
oldPNG = file.read()
file.close()
if oldPNG[:8] != pngheader:
return None
newPNG = oldPNG[:8]
chunkPos = len(newPNG)
idatAcc = ""
breakLoop = False
# For each chunk in the PNG file
while chunkPos < len(oldPNG):
skip = False
# Reading chunk
chunkLength = oldPNG[chunkPos:chunkPos+4]
chunkLength = unpack(">L", chunkLength)[0]
chunkType = oldPNG[chunkPos+4 : chunkPos+8]
chunkData = oldPNG[chunkPos+8:chunkPos+8+chunkLength]
chunkCRC = oldPNG[chunkPos+chunkLength+8:chunkPos+chunkLength+12]
chunkCRC = unpack(">L", chunkCRC)[0]
chunkPos += chunkLength + 12
# Parsing the header chunk
if chunkType == "IHDR":
width = unpack(">L", chunkData[0:4])[0]
height = unpack(">L", chunkData[4:8])[0]
# Parsing the image chunk
if chunkType == "IDAT":
# Store the chunk data for later decompression
idatAcc += chunkData
skip = True
# Removing CgBI chunk
if chunkType == "CgBI":
skip = True
# Add all accumulated IDATA chunks
if chunkType == "IEND":
try:
# Uncompressing the image chunk
bufSize = width * height * 4 + height
chunkData = decompress( idatAcc, -15, bufSize)
except Exception, e:
# The PNG image is normalized
print e
return None
chunkType = "IDAT"
# Swapping red & blue bytes for each pixel
newdata = ""
for y in xrange(height):
i = len(newdata)
newdata += chunkData[i]
for x in xrange(width):
i = len(newdata)
newdata += chunkData[i+2]
newdata += chunkData[i+1]
newdata += chunkData[i+0]
newdata += chunkData[i+3]
# Compressing the image chunk
chunkData = newdata
chunkData = compress( chunkData )
chunkLength = len( chunkData )
chunkCRC = crc32(chunkType)
chunkCRC = crc32(chunkData, chunkCRC)
chunkCRC = (chunkCRC + 0x100000000) % 0x100000000
breakLoop = True
if not skip:
newPNG += pack(">L", chunkLength)
newPNG += chunkType
if chunkLength > 0:
newPNG += chunkData
newPNG += pack(">L", chunkCRC)
if breakLoop:
break
return newPNG
def updatePNG(filename):
data = getNormalizedPNG(filename)
if data != None:
file = open(filename, "wb")
file.write(data)
file.close()
return True
return data
def getFiles(base):
global _dirs
global _pngs
if base == ".":
_dirs = []
_pngs = []
if base in _dirs:
return
files = os.listdir(base)
for file in files:
filepath = os.path.join(base, file)
try:
st = os.lstat(filepath)
except os.error:
continue
if stat.S_ISDIR(st.st_mode):
if not filepath in _dirs:
getFiles(filepath)
_dirs.append( filepath )
elif file[-4:].lower() == ".png":
if not filepath in _pngs:
_pngs.append( filepath )
if base == ".":
return _dirs, _pngs
print "-----------------------------------"
print " iPhone PNG Images Normalizer v1.0"
print "-----------------------------------"
print " "
print "[+] Searching PNG files...",
dirs, pngs = getFiles(".")
print "ok"
if len(pngs) == 0:
print " "
print "[!] Alert: There are no PNG files found. Move this python file to the folder that contains the PNG files to normalize."
exit()
print " "
print " - %d PNG files were found at this folder (and subfolders)." % len(pngs)
print " "
while True:
normalize = raw_input("[?] Do you want to normalize all images (Y/N)? ").lower()
if len(normalize) > 0 and (normalize[0] == "y" or normalize[0] == "n"):
break
normalized = 0
if normalize[0] == "y":
for ipng in xrange(len(pngs)):
perc = (float(ipng) / len(pngs)) * 100.0
print "%.2f%% %s" % (perc, pngs[ipng])
if updatePNG(pngs[ipng]):
normalized += 1
print " "
print "[+] %d PNG files were normalized." % normalized
@PythEch

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PythEch Dec 31, 2012

Thank you very much indeed!

PythEch commented Dec 31, 2012

Thank you very much indeed!

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lloydsheng Jan 27, 2014

thanks for your work!

lloydsheng commented Jan 27, 2014

thanks for your work!

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AlexBarbulescu Feb 5, 2014

I get Syntax error

AlexBarbulescu commented Feb 5, 2014

I get Syntax error

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huahua8893 Jun 26, 2015

it's worked,thank you for share

huahua8893 commented Jun 26, 2015

it's worked,thank you for share

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BenRomberg Aug 18, 2015

Great stuff, the only script on the net I've found to work. Thanks!

BenRomberg commented Aug 18, 2015

Great stuff, the only script on the net I've found to work. Thanks!

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offbye May 27, 2016

亲测可用

offbye commented May 27, 2016

亲测可用

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offbye May 27, 2016

Great job,I have used it in my jenkins CI scripts.

offbye commented May 27, 2016

Great job,I have used it in my jenkins CI scripts.

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ForeverAndAlways Jul 31, 2017

Great job!!! Thanks!
非常赞啊!

ForeverAndAlways commented Jul 31, 2017

Great job!!! Thanks!
非常赞啊!

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