def DQT(self, marker):
#
# Define quantization table. Support baseline 8-bit tables
# only. Note that there might be more than one table in
# each marker.
# FIXME: The quantization tables can be used to estimate the
# compression quality.
n = i16(self.fp.read(2))-2
s = ImageFile._safe_read(self.fp, n)
while len(s):
if len(s) < 65:
raise SyntaxError("bad quantization table marker")
v = i8(s[0])
if v//16 == 0:
self.quantization[v & 15] = array.array("b", s[1:65])
s = s[65:]
else:
return # FIXME: add code to read 16-bit tables!
# raise SyntaxError, "bad quantization table element size"
#
# JPEG marker table
python类ImageFile()的实例源码
def _save(im, fp, filename):
if im.mode != "1":
raise IOError("cannot write mode %s as XBM" % im.mode)
fp.write(("#define im_width %d\n" % im.size[0]).encode('ascii'))
fp.write(("#define im_height %d\n" % im.size[1]).encode('ascii'))
hotspot = im.encoderinfo.get("hotspot")
if hotspot:
fp.write(("#define im_x_hot %d\n" % hotspot[0]).encode('ascii'))
fp.write(("#define im_y_hot %d\n" % hotspot[1]).encode('ascii'))
fp.write(b"static char im_bits[] = {\n")
ImageFile._save(im, fp, [("xbm", (0, 0)+im.size, 0, None)])
fp.write(b"};\n")
def _save(im, fp, filename):
if im.mode[0] != "F":
im = im.convert('F')
hdr = makeSpiderHeader(im)
if len(hdr) < 256:
raise IOError("Error creating Spider header")
# write the SPIDER header
try:
fp = open(filename, 'wb')
except:
raise IOError("Unable to open %s for writing" % filename)
fp.writelines(hdr)
rawmode = "F;32NF" # 32-bit native floating point
ImageFile._save(im, fp, [("raw", (0, 0)+im.size, 0, (rawmode, 0, 1))])
fp.close()
def chunk_tRNS(self, pos, length):
# transparency
s = ImageFile._safe_read(self.fp, length)
if self.im_mode == "P":
if _simple_palette.match(s):
i = s.find(b"\0")
if i >= 0:
self.im_info["transparency"] = i
elif _null_palette.match(s):
self.im_info["transparency"] = 0
else:
self.im_info["transparency"] = s
elif self.im_mode == "L":
self.im_info["transparency"] = i16(s)
elif self.im_mode == "RGB":
self.im_info["transparency"] = i16(s), i16(s[2:]), i16(s[4:])
return s
def _save(im, fp, filename):
if im.mode[0] != "F":
im = im.convert('F')
hdr = makeSpiderHeader(im)
if len(hdr) < 256:
raise IOError("Error creating Spider header")
# write the SPIDER header
try:
fp = open(filename, 'wb')
except:
raise IOError("Unable to open %s for writing" % filename)
fp.writelines(hdr)
rawmode = "F;32NF" # 32-bit native floating point
ImageFile._save(im, fp, [("raw", (0, 0)+im.size, 0, (rawmode, 0, 1))])
fp.close()
def _save(im, fp, filename):
if im.mode[0] != "F":
im = im.convert('F')
hdr = makeSpiderHeader(im)
if len(hdr) < 256:
raise IOError("Error creating Spider header")
# write the SPIDER header
try:
fp = open(filename, 'wb')
except:
raise IOError("Unable to open %s for writing" % filename)
fp.writelines(hdr)
rawmode = "F;32NF" # 32-bit native floating point
ImageFile._save(im, fp, [("raw", (0, 0)+im.size, 0, (rawmode, 0, 1))])
fp.close()
def DQT(self, marker):
#
# Define quantization table. Support baseline 8-bit tables
# only. Note that there might be more than one table in
# each marker.
# FIXME: The quantization tables can be used to estimate the
# compression quality.
n = i16(self.fp.read(2))-2
s = ImageFile._safe_read(self.fp, n)
while len(s):
if len(s) < 65:
raise SyntaxError("bad quantization table marker")
v = i8(s[0])
if v//16 == 0:
self.quantization[v & 15] = array.array("B", s[1:65])
s = s[65:]
else:
return # FIXME: add code to read 16-bit tables!
# raise SyntaxError, "bad quantization table element size"
#
# JPEG marker table
def _save(im, fp, filename):
if im.mode != "1":
raise IOError("cannot write mode %s as XBM" % im.mode)
fp.write(("#define im_width %d\n" % im.size[0]).encode('ascii'))
fp.write(("#define im_height %d\n" % im.size[1]).encode('ascii'))
hotspot = im.encoderinfo.get("hotspot")
if hotspot:
fp.write(("#define im_x_hot %d\n" % hotspot[0]).encode('ascii'))
fp.write(("#define im_y_hot %d\n" % hotspot[1]).encode('ascii'))
fp.write(b"static char im_bits[] = {\n")
ImageFile._save(im, fp, [("xbm", (0, 0)+im.size, 0, None)])
fp.write(b"};\n")
def _save(im, fp, filename):
if im.mode[0] != "F":
im = im.convert('F')
hdr = makeSpiderHeader(im)
if len(hdr) < 256:
raise IOError("Error creating Spider header")
# write the SPIDER header
try:
fp = open(filename, 'wb')
except:
raise IOError("Unable to open %s for writing" % filename)
fp.writelines(hdr)
rawmode = "F;32NF" # 32-bit native floating point
ImageFile._save(im, fp, [("raw", (0, 0)+im.size, 0, (rawmode, 0, 1))])
fp.close()
def crc(self, cid, data):
"Read and verify checksum"
# Skip CRC checks for ancillary chunks if allowed to load truncated images
# 5th byte of first char is 1 [specs, section 5.4]
if ImageFile.LOAD_TRUNCATED_IMAGES and (i8(cid[0]) >> 5 & 1):
self.crc_skip(cid, data)
return
try:
crc1 = Image.core.crc32(data, Image.core.crc32(cid))
crc2 = i16(self.fp.read(2)), i16(self.fp.read(2))
if crc1 != crc2:
raise SyntaxError("broken PNG file (bad header checksum in %s)"
% cid)
except struct.error:
raise SyntaxError("broken PNG file (incomplete checksum in %s)"
% cid)
def chunk_tRNS(self, pos, length):
# transparency
s = ImageFile._safe_read(self.fp, length)
if self.im_mode == "P":
if _simple_palette.match(s):
# tRNS contains only one full-transparent entry,
# other entries are full opaque
i = s.find(b"\0")
if i >= 0:
self.im_info["transparency"] = i
else:
# otherwise, we have a byte string with one alpha value
# for each palette entry
self.im_info["transparency"] = s
elif self.im_mode == "L":
self.im_info["transparency"] = i16(s)
elif self.im_mode == "RGB":
self.im_info["transparency"] = i16(s), i16(s[2:]), i16(s[4:])
return s
def chunk_tEXt(self, pos, length):
# text
s = ImageFile._safe_read(self.fp, length)
try:
k, v = s.split(b"\0", 1)
except ValueError:
# fallback for broken tEXt tags
k = s
v = b""
if k:
if bytes is not str:
k = k.decode('latin-1', 'strict')
v = v.decode('latin-1', 'replace')
self.im_info[k] = self.im_text[k] = v
self.check_text_memory(len(v))
return s
def DQT(self, marker):
#
# Define quantization table. Support baseline 8-bit tables
# only. Note that there might be more than one table in
# each marker.
# FIXME: The quantization tables can be used to estimate the
# compression quality.
n = i16(self.fp.read(2))-2
s = ImageFile._safe_read(self.fp, n)
while len(s):
if len(s) < 65:
raise SyntaxError("bad quantization table marker")
v = i8(s[0])
if v//16 == 0:
self.quantization[v & 15] = array.array("b", s[1:65])
s = s[65:]
else:
return # FIXME: add code to read 16-bit tables!
# raise SyntaxError, "bad quantization table element size"
#
# JPEG marker table
def _save(im, fp, filename):
if im.mode != "1":
raise IOError("cannot write mode %s as XBM" % im.mode)
fp.write(("#define im_width %d\n" % im.size[0]).encode('ascii'))
fp.write(("#define im_height %d\n" % im.size[1]).encode('ascii'))
hotspot = im.encoderinfo.get("hotspot")
if hotspot:
fp.write(("#define im_x_hot %d\n" % hotspot[0]).encode('ascii'))
fp.write(("#define im_y_hot %d\n" % hotspot[1]).encode('ascii'))
fp.write(b"static char im_bits[] = {\n")
ImageFile._save(im, fp, [("xbm", (0, 0)+im.size, 0, None)])
fp.write(b"};\n")
def _save(im, fp, filename):
if im.mode[0] != "F":
im = im.convert('F')
hdr = makeSpiderHeader(im)
if len(hdr) < 256:
raise IOError("Error creating Spider header")
# write the SPIDER header
try:
fp = open(filename, 'wb')
except:
raise IOError("Unable to open %s for writing" % filename)
fp.writelines(hdr)
rawmode = "F;32NF" # 32-bit native floating point
ImageFile._save(im, fp, [("raw", (0, 0)+im.size, 0, (rawmode, 0, 1))])
fp.close()
def chunk_tRNS(self, pos, length):
# transparency
s = ImageFile._safe_read(self.fp, length)
if self.im_mode == "P":
if _simple_palette.match(s):
i = s.find(b"\0")
if i >= 0:
self.im_info["transparency"] = i
elif _null_palette.match(s):
self.im_info["transparency"] = 0
else:
self.im_info["transparency"] = s
elif self.im_mode == "L":
self.im_info["transparency"] = i16(s)
elif self.im_mode == "RGB":
self.im_info["transparency"] = i16(s), i16(s[2:]), i16(s[4:])
return s
def DQT(self, marker):
#
# Define quantization table. Support baseline 8-bit tables
# only. Note that there might be more than one table in
# each marker.
# FIXME: The quantization tables can be used to estimate the
# compression quality.
n = i16(self.fp.read(2))-2
s = ImageFile._safe_read(self.fp, n)
while len(s):
if len(s) < 65:
raise SyntaxError("bad quantization table marker")
v = i8(s[0])
if v//16 == 0:
self.quantization[v & 15] = array.array("B", s[1:65])
s = s[65:]
else:
return # FIXME: add code to read 16-bit tables!
# raise SyntaxError, "bad quantization table element size"
#
# JPEG marker table
def _save(im, fp, filename):
if im.mode != "1":
raise IOError("cannot write mode %s as XBM" % im.mode)
fp.write(("#define im_width %d\n" % im.size[0]).encode('ascii'))
fp.write(("#define im_height %d\n" % im.size[1]).encode('ascii'))
hotspot = im.encoderinfo.get("hotspot")
if hotspot:
fp.write(("#define im_x_hot %d\n" % hotspot[0]).encode('ascii'))
fp.write(("#define im_y_hot %d\n" % hotspot[1]).encode('ascii'))
fp.write(b"static char im_bits[] = {\n")
ImageFile._save(im, fp, [("xbm", (0, 0)+im.size, 0, None)])
fp.write(b"};\n")
def _save(im, fp, filename):
if im.mode[0] != "F":
im = im.convert('F')
hdr = makeSpiderHeader(im)
if len(hdr) < 256:
raise IOError("Error creating Spider header")
# write the SPIDER header
try:
fp = open(filename, 'wb')
except:
raise IOError("Unable to open %s for writing" % filename)
fp.writelines(hdr)
rawmode = "F;32NF" # 32-bit native floating point
ImageFile._save(im, fp, [("raw", (0, 0)+im.size, 0, (rawmode, 0, 1))])
fp.close()
def crc(self, cid, data):
"Read and verify checksum"
# Skip CRC checks for ancillary chunks if allowed to load truncated images
# 5th byte of first char is 1 [specs, section 5.4]
if ImageFile.LOAD_TRUNCATED_IMAGES and (i8(cid[0]) >> 5 & 1):
self.crc_skip(cid, data)
return
try:
crc1 = Image.core.crc32(data, Image.core.crc32(cid))
crc2 = i16(self.fp.read(2)), i16(self.fp.read(2))
if crc1 != crc2:
raise SyntaxError("broken PNG file (bad header checksum in %s)"
% cid)
except struct.error:
raise SyntaxError("broken PNG file (incomplete checksum in %s)"
% cid)
def chunk_tRNS(self, pos, length):
# transparency
s = ImageFile._safe_read(self.fp, length)
if self.im_mode == "P":
if _simple_palette.match(s):
# tRNS contains only one full-transparent entry,
# other entries are full opaque
i = s.find(b"\0")
if i >= 0:
self.im_info["transparency"] = i
else:
# otherwise, we have a byte string with one alpha value
# for each palette entry
self.im_info["transparency"] = s
elif self.im_mode == "L":
self.im_info["transparency"] = i16(s)
elif self.im_mode == "RGB":
self.im_info["transparency"] = i16(s), i16(s[2:]), i16(s[4:])
return s
def chunk_tEXt(self, pos, length):
# text
s = ImageFile._safe_read(self.fp, length)
try:
k, v = s.split(b"\0", 1)
except ValueError:
# fallback for broken tEXt tags
k = s
v = b""
if k:
if bytes is not str:
k = k.decode('latin-1', 'strict')
v = v.decode('latin-1', 'replace')
self.im_info[k] = self.im_text[k] = v
self.check_text_memory(len(v))
return s
def DQT(self, marker):
#
# Define quantization table. Support baseline 8-bit tables
# only. Note that there might be more than one table in
# each marker.
# FIXME: The quantization tables can be used to estimate the
# compression quality.
n = i16(self.fp.read(2))-2
s = ImageFile._safe_read(self.fp, n)
while len(s):
if len(s) < 65:
raise SyntaxError("bad quantization table marker")
v = i8(s[0])
if v//16 == 0:
self.quantization[v & 15] = array.array("B", s[1:65])
s = s[65:]
else:
return # FIXME: add code to read 16-bit tables!
# raise SyntaxError, "bad quantization table element size"
#
# JPEG marker table
def _save(im, fp, filename):
if im.mode != "1":
raise IOError("cannot write mode %s as XBM" % im.mode)
fp.write(("#define im_width %d\n" % im.size[0]).encode('ascii'))
fp.write(("#define im_height %d\n" % im.size[1]).encode('ascii'))
hotspot = im.encoderinfo.get("hotspot")
if hotspot:
fp.write(("#define im_x_hot %d\n" % hotspot[0]).encode('ascii'))
fp.write(("#define im_y_hot %d\n" % hotspot[1]).encode('ascii'))
fp.write(b"static char im_bits[] = {\n")
ImageFile._save(im, fp, [("xbm", (0, 0)+im.size, 0, None)])
fp.write(b"};\n")
def _save(im, fp, filename):
if im.mode[0] != "F":
im = im.convert('F')
hdr = makeSpiderHeader(im)
if len(hdr) < 256:
raise IOError("Error creating Spider header")
# write the SPIDER header
try:
fp = open(filename, 'wb')
except:
raise IOError("Unable to open %s for writing" % filename)
fp.writelines(hdr)
rawmode = "F;32NF" # 32-bit native floating point
ImageFile._save(im, fp, [("raw", (0, 0)+im.size, 0, (rawmode, 0, 1))])
fp.close()
def crc(self, cid, data):
"Read and verify checksum"
# Skip CRC checks for ancillary chunks if allowed to load truncated images
# 5th byte of first char is 1 [specs, section 5.4]
if ImageFile.LOAD_TRUNCATED_IMAGES and (i8(cid[0]) >> 5 & 1):
self.crc_skip(cid, data)
return
try:
crc1 = Image.core.crc32(data, Image.core.crc32(cid))
crc2 = i16(self.fp.read(2)), i16(self.fp.read(2))
if crc1 != crc2:
raise SyntaxError("broken PNG file (bad header checksum in %s)"
% cid)
except struct.error:
raise SyntaxError("broken PNG file (incomplete checksum in %s)"
% cid)
def chunk_tRNS(self, pos, length):
# transparency
s = ImageFile._safe_read(self.fp, length)
if self.im_mode == "P":
if _simple_palette.match(s):
# tRNS contains only one full-transparent entry,
# other entries are full opaque
i = s.find(b"\0")
if i >= 0:
self.im_info["transparency"] = i
else:
# otherwise, we have a byte string with one alpha value
# for each palette entry
self.im_info["transparency"] = s
elif self.im_mode == "L":
self.im_info["transparency"] = i16(s)
elif self.im_mode == "RGB":
self.im_info["transparency"] = i16(s), i16(s[2:]), i16(s[4:])
return s
def chunk_tEXt(self, pos, length):
# text
s = ImageFile._safe_read(self.fp, length)
try:
k, v = s.split(b"\0", 1)
except ValueError:
# fallback for broken tEXt tags
k = s
v = b""
if k:
if bytes is not str:
k = k.decode('latin-1', 'strict')
v = v.decode('latin-1', 'replace')
self.im_info[k] = self.im_text[k] = v
self.check_text_memory(len(v))
return s
def _save(im, fp, filename):
if im.mode != "1":
raise IOError("cannot write mode %s as XBM" % im.mode)
fp.write(("#define im_width %d\n" % im.size[0]).encode('ascii'))
fp.write(("#define im_height %d\n" % im.size[1]).encode('ascii'))
hotspot = im.encoderinfo.get("hotspot")
if hotspot:
fp.write(("#define im_x_hot %d\n" % hotspot[0]).encode('ascii'))
fp.write(("#define im_y_hot %d\n" % hotspot[1]).encode('ascii'))
fp.write(b"static char im_bits[] = {\n")
ImageFile._save(im, fp, [("xbm", (0, 0)+im.size, 0, None)])
fp.write(b"};\n")
def _save(im, fp, filename):
if im.mode[0] != "F":
im = im.convert('F')
hdr = makeSpiderHeader(im)
if len(hdr) < 256:
raise IOError("Error creating Spider header")
# write the SPIDER header
try:
fp = open(filename, 'wb')
except:
raise IOError("Unable to open %s for writing" % filename)
fp.writelines(hdr)
rawmode = "F;32NF" # 32-bit native floating point
ImageFile._save(im, fp, [("raw", (0, 0)+im.size, 0, (rawmode, 0, 1))])
fp.close()
