def setValue(self, val): #from python to binary
#we support writing unsigned (short, long, rational), ascii
self.value = val
if self.type in [3,4]: #short, long
if type(val) not in [[], ()]:
val = [val]
self.valueFlat = ''.join([util.setNr(n, self.bytes, self.endian) for n in val])
self.count = len(val)
elif self.type == 5: #rational
self.valueFlat = ''.join([util.setNr(n, 4, self.endian) + util.setNr(d, 4, self.endian) for n,d in self.value])
self.count = 1
else:
if self.type == 2: #ascii
self.valueFlat = self.value + "\x00" #must be NULL terminated string
self.count = len(self.value) + 1
if self.count < 4:
self.valueFlat = self.valueFlat.rjust(4) #self.valueFlat + ("\x00" * (4-len(self.valueFlat)))
self.count = 4
else:
self.valueFlat = self.value
self.count = len(self.value)
if self.count < 4:
self.valueFlat = self.valueFlat + ("\x00" * (4-len(self.valueFlat)))
self.count = 4
self.len = self.bytes * self.count
def binary(self):
#http://www.iptc.org/std/IIM/4.1/specification/IIMV4.1.pdf (pag 15)
res = self.marker + self.type
val = self.value
#only parse it this way but not write this way
#if len(val) % 2 != 0: #Pad with a NULL if not even size but let length be as it was
# val += "\x00"
if len(self.value) < 32767:
res += util.setNr(len(self.value), 2) + val
else:
#lengthOfValueLength + valueLength + value (4 should be enough for lengthOfValueLength)
res += util.setNr(4, 2) + util.setNr(len(self.value), 4) + val
return res
def binary(self):
#http://www.iptc.org/std/IIM/4.1/specification/IIMV4.1.pdf (pag 15)
res = self.marker + self.type
val = self.value
#only parse it this way but not write this way
#if len(val) % 2 != 0: #Pad with a NULL if not even size but let length be as it was
# val += "\x00"
if len(self.value) < 32767:
res += util.setNr(len(self.value), 2) + val
else:
#lengthOfValueLength + valueLength + value (4 should be enough for lengthOfValueLength)
res += util.setNr(4, 2) + util.setNr(len(self.value), 4) + val
return res
def _write(value, file, marker):
"""-Overwrights <marker> segment with given <value>
-if <marker> segment does not already exist then it will write it
right before the image segment (SOF - FFC0)
"""
markerSeg, sof, length, im = _process(file, marker)
if markerSeg or sof:
lenHex = util.setNr(len(value) + 2, "short") #the length on 2 bytes
segment = "\xFF" + marker + lenHex + value #segment = marker + value length + value
pos = im.tell() - 4
im.seek(0)
before = im.read(pos)
if markerSeg:
im.seek(util.getNr(length) + 2,
1) #skip over existing segment, including marker
after = im.read()
im.reset()
im.write(before)
im.write(segment)
im.write(after)
im.close()
return im
else:
im.close()
raise NoImageFound, "There is no image in this image file ?"
def _write(value, file, marker):
"""-Overwrights <marker> segment with given <value>
-if <marker> segment does not already exist then it will write it
right before the image segment (SOF - FFC0)
"""
markerSeg, sof, length, im = _process(file, marker)
if markerSeg or sof:
lenHex = util.setNr(len(value)+2, "short") #the length on 2 bytes
segment = "\xFF" + marker + lenHex + value #segment = marker + value length + value
pos = im.tell() - 4
im.seek(0)
before = im.read(pos)
if markerSeg:
im.seek(util.getNr(length) + 2, 1) #skip over existing segment, including marker
after = im.read()
im.reset()
im.write(before)
im.write(segment)
im.write(after)
im.close()
return im
else:
im.close()
raise NoImageFound, "There is no image in this image file ?"
def binary(self):
res = ""
for ds in self.datasets:
res += ds.binary()
length = util.setNr(len(res), 2)
if len(res) % 2 != 0:
# Pad with a blank if not even size but let length be as it was
res += "\x00"
return self.marker + self.type + self.padding + length + res
def binary(self):
res = ""
for ds in self.datasets:
res += ds.binary()
length = util.setNr(len(res), 2)
if len(res) % 2 != 0:
# Pad with a blank if not even size but let length be as it was
res += "\x00"
return self.marker + self.type + self.padding + length + res
def create(self, name, value):
if name in txt_datasets:
ds = DataSet('\x1c\x02', util.setNr(txt_datasets[name], 1), value, self)
self.datasets.append(ds)
return ds
else:
s = ["Only the following are supported:"]
for k in txt_datasets.keys():
s.append(k)
raise NotImplementedError("\n".join(s))
def create(self, name, value):
if name in txt_datasets:
ds = DataSet('\x1c\x02', util.setNr(txt_datasets[name], 1), value,
self)
self.datasets.append(ds)
return ds
else:
s = ["Only the following are supported:"]
for k in txt_datasets.keys():
s.append(k)
raise NotImplementedError("\n".join(s))
def set(self, tag, value, targetIfd, type_):
""" - Overwrite <tagID> tag with <value>.
- If tag does not already exist, build it in the specified <targetIfd>.
- The type (short, long, ascii, etc. as 3,4,2 etc.) need to be specified since this program will
probably never be aware of all posible tags and their specification. You may need to do some
research with exif.org to find the right type
"""
tagID = type(tag)==type(1) and util.setNr(tag)[2:] or tag #nr to str
for ifd in self.ifds:
for tag in ifd:
if tag.id == tagID or (self.endian == "II" and tag.id == util.reverse(tagID)):
tag.setValue(value)
return True
tag = FirstTag(tagID, value, type_, self) #don't have it yet, so create one
targetIfd.append(tag)
def get(self, tags, value=True, parse_value=True):
"return value for given <tags> (1 tag or a list of tags as number or string hex value in big endian)"
if type(tags) in (type(""), type(1)):
tags = [tags] #allow searching multiple tags at once
tags = [type(t)==type(1) and util.setNr(t)[2:] or t for t in tags] #nr to str for each tag
if self.endian == "II":
tags = [t[1]+t[0] for t in tags]
res = []
for ifd in self.ifds:
for tag in ifd:
if tag.id in tags:
if value:
res.append(tag.getValue(parse_value))
else:
res.append(tag)
if len(res) == len(tags):
break
if len(res) == 1: return res[0]
if len(res) == 0: return None
return res
def binary(self):
""" return Exif as is needed to be written into the jpeg file
"""
exifPointer = interopPointer = gpsPointer= None
#endian + fixed number 42 + 8 (ifd0 starts right after tiff header)
fixed42 = self.endian == "MM" and "\x00\x2A" or "\x2A\x00"
ifd0offset = self.endian == "MM" and "\x00\x00\x00\x08" or "\x08\x00\x00\x00"
res = self.endian + fixed42 + ifd0offset
offset = 8 #total bytes for endian, fixed, ifd0 offset
for ifd in self.ifds:
#this is a come back later to fill in a gap with offsets to ifd, when we know the offset
if ifd is self.exif and self.exif:
res = res[:exifPointer] + util.setNr(len(res), 4, self.endian) + res[exifPointer+4:]
if ifd is self.interop and self.interop:
res = res[:interopPointer] + util.setNr(len(res), 4, self.endian) + res[interopPointer+4:]
if ifd is self.gps and self.gps:
res = res[:gpsPointer] + util.setNr(len(res), 4, self.endian) + res[gpsPointer+4:]
headLen = 2 #nr of tags
nrTags = len(ifd)
headLen += nrTags * 12 #all tags
if ifd is self.ifd0:
headLen += 4 #pointer to ifd1
valOffset = offset + headLen
res += util.setNr(nrTags, 2, self.endian)
tagValOffset = 0
for tag in ifd:
res += tag.id #2 bytes
res += util.setNr(tag.type, 2, self.endian) #4
res += util.setNr(tag.count, 4, self.endian) #8
if tag.id == "\x87\x69" or (self.endian=="II" and tag.id == "\x69\x87"): #exif
exifPointer = len(res)
res += util.setNr(0, 4, self.endian) #will set later, now just to have correct length
elif tag.id == "\xA0\x05" or (self.endian=="II" and tag.id == "\x05\xA0"): #interopelability
interopPointer = len(res)
res += util.setNr(0, 4, self.endian)
elif tag.id == "\x88\x25" or (self.endian=="II" and tag.id == "\x25\x88"): #gps
gpsPointer = len(res)
res += util.setNr(0, 4, self.endian)
elif len(tag.valueFlat) <= 4:
res += tag.valueFlat #12
else:
res += util.setNr(valOffset + tagValOffset, 4, self.endian) #12
tagValOffset += tag.len
if ifd is self.ifd0:
ifd1Pointer = len(res) #pointer to ifd1
res += util.setNr(0, 4, self.endian)
for tag in ifd:
if len(tag.valueFlat) > 4:
res += tag.valueFlat
offset = len(res)
res = res[:ifd1Pointer] + util.setNr(len(res), 4, self.endian) + res[ifd1Pointer+4:]
res += self.ifd1
return "Exif\x00\x00" + res
'SubsecTimeDigitized': 0x9292,
'TimeZoneOffset': 0x882A, # TODO: I hope TimeZoneOffset is not a pointer to yet another ifd
'Copyright': 0x8298,
'Exif version': 0x9000,
'Exif IFD Pointer': 0x8769,
'GPS IFD Pointer': 0x8825,
'Interoperability IFD': 0xA005,
'FlashPixVersion': 0xA000,
'FNumber': 0x829D,
'CompressedBitsPerPixel': 0x9102,
'ISOSpeedRatings': 0x8827,
'InteroperabilityVersion': 0x0002,
'InteroperabilityIndex': 0x0001,
'RelatedImageWidth': 0x1001,
'RelatedImageLength': 0x1002,
'SensingMethod': 0xA217,
'FocalPlaneXResolution': 0xA20E,
'FocalPlaneYResolution': 0xA20F,
'FocalPlaneResolutionUnit': 0xA210
}
exif_tags_description = {}
for key in exif_tags:
val = exif_tags[key]
if type(val) == type(()):
val = (util.setNr(val[0])[2:], val[1]) #MM int
exif_tags_description[val[0]] = (key, val[1])
else:
val = util.setNr(val, 4)[2:]
exif_tags_description[val] = key
exif_tags[key] = val
