#Copyright ReportLab Europe Ltd. 2000-2012
#see license.txt for license details
#history http://www.reportlab.co.uk/cgi-bin/viewcvs.cgi/public/reportlab/trunk/reportlab/pdfbase/pdfutils.py
__version__=''' $Id$ '''
__doc__=''
# pdfutils.py - everything to do with images, streams,
# compression, and some constants
import sys
import os
import binascii
from reportlab import rl_config
from reportlab.lib.utils import getBytesIO, ImageReader, isStrType, isUnicodeType, isPython3
LINEEND = '\015\012'
def _chunker(src,dst=[],chunkSize=60):
for i in range(0,len(src),chunkSize):
dst.append(src[i:i+chunkSize])
return dst
##########################################################
#
# Image compression helpers. Preprocessing a directory
# of images will offer a vast speedup.
#
##########################################################
_mode2cs = {'RGB':'RGB', 'CMYK': 'CMYK', 'L': 'G'}
_mode2bpp = {'RGB': 3, 'CMYK':4, 'L':1}
def makeA85Image(filename,IMG=None):
import zlib
img = ImageReader(filename)
if IMG is not None: IMG.append(img)
imgwidth, imgheight = img.getSize()
raw = img.getRGBData()
code = []
append = code.append
# this describes what is in the image itself
append('BI')
append('/W %s /H %s /BPC 8 /CS /%s /F [/A85 /Fl]' % (imgwidth, imgheight,_mode2cs[img.mode]))
append('ID')
#use a flate filter and Ascii Base 85
assert len(raw) == imgwidth * imgheight*_mode2bpp[img.mode], "Wrong amount of data for image"
compressed = zlib.compress(raw) #this bit is very fast...
encoded = _AsciiBase85Encode(compressed) #...sadly this may not be
#append in blocks of 60 characters
_chunker(encoded,code)
append('EI')
return code
def makeRawImage(filename,IMG=None):
import zlib
img = ImageReader(filename)
if IMG is not None: IMG.append(img)
imgwidth, imgheight = img.getSize()
raw = img.getRGBData()
code = []
append = code.append
# this describes what is in the image itself
append('BI')
append('/W %s /H %s /BPC 8 /CS /%s /F [/Fl]' % (imgwidth, imgheight,_mode2cs[img.mode]))
append('ID')
#use a flate filter
assert len(raw) == imgwidth * imgheight*_mode2bpp[img.mode], "Wrong amount of data for image"
compressed = zlib.compress(raw) #this bit is very fast...
#append in blocks of 60 characters
_chunker(compressed,code)
append('EI')
return code
def cacheImageFile(filename, returnInMemory=0, IMG=None):
"Processes image as if for encoding, saves to a file with .a85 extension."
cachedname = os.path.splitext(filename)[0] + (rl_config.useA85 and '.a85' or '.bin')
if filename==cachedname:
if cachedImageExists(filename):
from reportlab.lib.utils import open_for_read
if returnInMemory: return filter(None,open_for_read(cachedname).read().split(LINEEND))
else:
raise IOError('No such cached image %s' % filename)
else:
if rl_config.useA85:
code = makeA85Image(filename,IMG)
else:
code = makeRawImage(filename,IMG)
if returnInMemory: return code
#save it to a file
f = open(cachedname,'wb')
f.write(LINEEND.join(code)+LINEEND)
f.close()
if rl_config.verbose:
print('cached image as %s' % cachedname)
def preProcessImages(spec):
"""Preprocesses one or more image files.
Accepts either a filespec ('C:\mydir\*.jpg') or a list
of image filenames, crunches them all to save time. Run this
to save huge amounts of time when repeatedly building image
documents."""
import types, glob
if type(spec) is types.StringType:
filelist = glob.glob(spec)
else: #list or tuple OK
filelist = spec
for filename in filelist:
if cachedImageExists(filename):
if rl_config.verbose:
print('cached version of %s already exists' % filename)
else:
cacheImageFile(filename)
def cachedImageExists(filename):
"""Determines if a cached image already exists for a given file.
Determines if a cached image exists which has the same name
and equal or newer date to the given file."""
cachedname = os.path.splitext(filename)[0] + (rl_config.useA85 and '.a85' or 'bin')
if os.path.isfile(cachedname):
#see if it is newer
original_date = os.stat(filename)[8]
cached_date = os.stat(cachedname)[8]
if original_date > cached_date:
return 0
else:
return 1
else:
return 0
##############################################################
#
# PDF Helper functions
#
##############################################################
try:
from _rl_accel import escapePDF, _instanceEscapePDF
_escape = escapePDF
except ImportError:
try:
from reportlab.lib._rl_accel import escapePDF, _instanceEscapePDF
_escape = escapePDF
except ImportError:
_instanceEscapePDF=None
_ESCAPEDICT={}
for c in range(256):
if c<32 or c>=127:
_ESCAPEDICT[c]= '\\%03o' % c
elif c in (ord('\\'),ord('('),ord(')')):
_ESCAPEDICT[c] = '\\'+chr(c)
else:
_ESCAPEDICT[c] = chr(c)
del c
#Michael Hudson donated this
def _escape(s):
r = []
for c in s:
if not type(c) is int:
c = ord(c)
r.append(_ESCAPEDICT[c])
return ''.join(r)
def _normalizeLineEnds(text,desired=LINEEND,unlikely='\x00\x01\x02\x03'):
"""Normalizes different line end character(s).
Ensures all instances of CR, LF and CRLF end up as
the specified one."""
return (text
.replace('\r\n', unlikely)
.replace('\r', unlikely)
.replace('\n', unlikely)
.replace(unlikely, desired))
def _AsciiHexEncode(input):
"""Encodes input using ASCII-Hex coding.
This is a verbose encoding used for binary data within
a PDF file. One byte binary becomes two bytes of ASCII.
Helper function used by images."""
if isUnicodeType(input):
input = input.encode('utf-8')
output = getBytesIO()
output.write(binascii.b2a_hex(input))
output.write(b'>')
return output.getvalue()
def _AsciiHexDecode(input):
"""Decodes input using ASCII-Hex coding.
Not used except to provide a test of the inverse function."""
#strip out all whitespace
if not isStrType(input):
input = input.decode('utf-8')
stripped = ''.join(input.split())
assert stripped[-1] == '>', 'Invalid terminator for Ascii Hex Stream'
stripped = stripped[:-1] #chop off terminator
assert len(stripped) % 2 == 0, 'Ascii Hex stream has odd number of bytes'
return ''.join([chr(int(stripped[i:i+2],16)) for i in range(0,len(stripped),2)])
if 1: # for testing always define this
def _AsciiBase85EncodePYTHON(input):
"""Encodes input using ASCII-Base85 coding.
This is a compact encoding used for binary data within
a PDF file. Four bytes of binary data become five bytes of
ASCII. This is the default method used for encoding images."""
# special rules apply if not a multiple of four bytes.
whole_word_count, remainder_size = divmod(len(input), 4)
cut = 4 * whole_word_count
body, lastbit = input[0:cut], input[cut:]
if isPython3 and isStrType(lastbit):
lastbit = lastbit.encode('utf-8')
out = [].append
for i in range(whole_word_count):
offset = i*4
b1 = body[offset]
b2 = body[offset+1]
b3 = body[offset+2]
b4 = body[offset+3]
if isStrType(b1): b1 = ord(b1)
if isStrType(b2): b2 = ord(b2)
if isStrType(b3): b3 = ord(b3)
if isStrType(b4): b4 = ord(b4)
if b1<128:
num = (((((b1<<8)|b2)<<8)|b3)<<8)|b4
else:
num = 16777216 * b1 + 65536 * b2 + 256 * b3 + b4
if num == 0:
#special case
out('z')
else:
#solve for five base-85 numbers
temp, c5 = divmod(num, 85)
temp, c4 = divmod(temp, 85)
temp, c3 = divmod(temp, 85)
c1, c2 = divmod(temp, 85)
assert ((85**4) * c1) + ((85**3) * c2) + ((85**2) * c3) + (85*c4) + c5 == num, 'dodgy code!'
out(chr(c1+33))
out(chr(c2+33))
out(chr(c3+33))
out(chr(c4+33))
out(chr(c5+33))
# now we do the final bit at the end. I repeated this separately as
# the loop above is the time-critical part of a script, whereas this
# happens only once at the end.
#encode however many bytes we have as usual
if remainder_size > 0:
while len(lastbit) < 4:
lastbit = lastbit + b'\000'
b1 = lastbit[0]
b2 = lastbit[1]
b3 = lastbit[2]
b4 = lastbit[3]
if isStrType(b1): b1 = ord(b1)
if isStrType(b2): b2 = ord(b2)
if isStrType(b3): b3 = ord(b3)
if isStrType(b4): b4 = ord(b4)
num = 16777216 * b1 + 65536 * b2 + 256 * b3 + b4
#solve for c1..c5
temp, c5 = divmod(num, 85)
temp, c4 = divmod(temp, 85)
temp, c3 = divmod(temp, 85)
c1, c2 = divmod(temp, 85)
#print 'encoding: %d %d %d %d -> %d -> %d %d %d %d %d' % (
# b1,b2,b3,b4,num,c1,c2,c3,c4,c5)
lastword = chr(c1+33) + chr(c2+33) + chr(c3+33) + chr(c4+33) + chr(c5+33)
#write out most of the bytes.
out(lastword[0:remainder_size + 1])
#terminator code for ascii 85
out('~>')
return ''.join(out.__self__)
def _AsciiBase85DecodePYTHON(input):
"""Decodes input using ASCII-Base85 coding.
This is not used - Acrobat Reader decodes for you
- but a round trip is essential for testing."""
#strip all whitespace
stripped = ''.join(input.split())
#check end
assert stripped[-2:] == '~>', 'Invalid terminator for Ascii Base 85 Stream'
stripped = stripped[:-2] #chop off terminator
#may have 'z' in it which complicates matters - expand them
stripped = stripped.replace('z','!!!!!')
# special rules apply if not a multiple of five bytes.
whole_word_count, remainder_size = divmod(len(stripped), 5)
#print '%d words, %d leftover' % (whole_word_count, remainder_size)
#assert remainder_size != 1, 'invalid Ascii 85 stream!'
cut = 5 * whole_word_count
body, lastbit = stripped[0:cut], stripped[cut:]
out = [].append
for i in range(whole_word_count):
offset = i*5
c1 = ord(body[offset]) - 33
c2 = ord(body[offset+1]) - 33
c3 = ord(body[offset+2]) - 33
c4 = ord(body[offset+3]) - 33
c5 = ord(body[offset+4]) - 33
num = ((85**4) * c1) + ((85**3) * c2) + ((85**2) * c3) + (85*c4) + c5
temp, b4 = divmod(num,256)
temp, b3 = divmod(temp,256)
b1, b2 = divmod(temp, 256)
assert num == 16777216 * b1 + 65536 * b2 + 256 * b3 + b4, 'dodgy code!'
out(chr(b1))
out(chr(b2))
out(chr(b3))
out(chr(b4))
#decode however many bytes we have as usual
if remainder_size > 0:
while len(lastbit) < 5:
lastbit = lastbit + '!'
c1 = ord(lastbit[0]) - 33
c2 = ord(lastbit[1]) - 33
c3 = ord(lastbit[2]) - 33
c4 = ord(lastbit[3]) - 33
c5 = ord(lastbit[4]) - 33
num = (((85*c1+c2)*85+c3)*85+c4)*85 + (c5
+(0,0,0xFFFFFF,0xFFFF,0xFF)[remainder_size])
temp, b4 = divmod(num,256)
temp, b3 = divmod(temp,256)
b1, b2 = divmod(temp, 256)
assert num == 16777216 * b1 + 65536 * b2 + 256 * b3 + b4, 'dodgy code!'
#print 'decoding: %d %d %d %d %d -> %d -> %d %d %d %d' % (
# c1,c2,c3,c4,c5,num,b1,b2,b3,b4)
#the last character needs 1 adding; the encoding loses
#data by rounding the number to x bytes, and when
#divided repeatedly we get one less
if remainder_size == 2:
lastword = chr(b1)
elif remainder_size == 3:
lastword = chr(b1) + chr(b2)
elif remainder_size == 4:
lastword = chr(b1) + chr(b2) + chr(b3)
else:
lastword = ''
out(lastword)
#terminator code for ascii 85
return ''.join(out.__self__)
try:
from _rl_accel import _AsciiBase85Encode # builtin or on the path
except ImportError:
try:
from reportlab.lib._rl_accel import _AsciiBase85Encode # where we think it should be
except ImportError:
_AsciiBase85Encode = _AsciiBase85EncodePYTHON
try:
from _rl_accel import _AsciiBase85Decode # builtin or on the path
except ImportError:
try:
from reportlab.lib._rl_accel import _AsciiBase85Decode # where we think it should be
except ImportError:
_AsciiBase85Decode = _AsciiBase85DecodePYTHON
def _wrap(input, columns=60):
"Wraps input at a given column size by inserting LINEEND characters."
output = []
length = len(input)
i = 0
pos = columns * i
while pos < length:
output.append(input[pos:pos+columns])
i = i + 1
pos = columns * i
#avoid HP printer problem
if len(output[-1])==1:
output[-2:] = [output[-2][:-1],output[-2][-1]+output[-1]]
return LINEEND.join(output)
#########################################################################
#
# JPEG processing code - contributed by Eric Johnson
#
#########################################################################
# Read data from the JPEG file. We should probably be using PIL to
# get this information for us -- but this way is more fun!
# Returns (width, height, color components) as a triple
# This is based on Thomas Merz's code from GhostScript (viewjpeg.ps)
def readJPEGInfo(image):
"Read width, height and number of components from open JPEG file."
import struct
from .pdfdoc import PDFError
#Acceptable JPEG Markers:
# SROF0=baseline, SOF1=extended sequential or SOF2=progressive
validMarkers = [0xC0, 0xC1, 0xC2]
#JPEG markers without additional parameters
noParamMarkers = \
[ 0xD0, 0xD1, 0xD2, 0xD3, 0xD4, 0xD5, 0xD6, 0xD7, 0xD8, 0x01 ]
#Unsupported JPEG Markers
unsupportedMarkers = \
[ 0xC3, 0xC5, 0xC6, 0xC7, 0xC8, 0xC9, 0xCA, 0xCB, 0xCD, 0xCE, 0xCF ]
#read JPEG marker segments until we find SOFn marker or EOF
done = 0
while not done:
x = struct.unpack('B', image.read(1))
if x[0] == 0xFF: #found marker
x = struct.unpack('B', image.read(1))
#print "Marker: ", '%0.2x' % x[0]
#check marker type is acceptable and process it
if x[0] in validMarkers:
image.seek(2, 1) #skip segment length
x = struct.unpack('B', image.read(1)) #data precision
if x[0] != 8:
raise PDFError('JPEG must have 8 bits per component')
y = struct.unpack('BB', image.read(2))
height = (y[0] << 8) + y[1]
y = struct.unpack('BB', image.read(2))
width = (y[0] << 8) + y[1]
y = struct.unpack('B', image.read(1))
color = y[0]
return width, height, color
elif x[0] in unsupportedMarkers:
raise PDFError('JPEG Unsupported JPEG marker: %0.2x' % x[0])
elif x[0] not in noParamMarkers:
#skip segments with parameters
#read length and skip the data
x = struct.unpack('BB', image.read(2))
image.seek( (x[0] << 8) + x[1] - 2, 1)
class _fusc:
def __init__(self,k, n):
assert k, 'Argument k should be a non empty string'
self._k = k
self._klen = len(k)
self._n = int(n) or 7
def encrypt(self,s):
return self.__rotate(_AsciiBase85Encode(''.join(map(chr,self.__fusc(list(map(ord,s)))))),self._n)
def decrypt(self,s):
return ''.join(map(chr,self.__fusc(list(map(ord,_AsciiBase85Decode(self.__rotate(s,-self._n)))))))
def __rotate(self,s,n):
l = len(s)
if n<0: n = l+n
n %= l
if not n: return s
return s[-n:]+s[:l-n]
def __fusc(self,s):
slen = len(s)
return list(map(lambda x,y: x ^ y,s,list(map(ord,((int(slen/self._klen)+1)*self._k)[:slen]))))