def chunk_DHDR(self, offset, nbytes):
"DHDR -- delta image follows"
# assertions
if self.count == 0:
raise SyntaxError("misplaced DHDR chunk")
s = self.fp.read(nbytes)
size, mode, rawmode = self.__getmodesize(s)
# delta header
diff = s[13]
offs = i32(s[14:18]), i32(s[18:22])
bbox = offs + (offs[0] + size[0], offs[1] + size[1])
if Image.DEBUG:
print("DHDR", diff, bbox)
# FIXME: decode and apply image
self.action = (b"DHDR", diff, bbox)
# setup decoder
self.im = Image.core.new(mode, size)
self.decoder = Image.core.zip_decoder(rawmode)
self.decoder.setimage(self.im, (0, 0) + size)
self.data = b""
return s
def __getmodesize(self, s, full=1):
size = i32(s), i32(s[4:])
try:
mode, rawmode = _MODES[(s[8], s[9])]
except:
raise SyntaxError("unknown image mode")
if full:
if s[12]:
pass # interlace not yet supported
if s[11]:
raise SyntaxError("unknown filter category")
return size, mode, rawmode
def chunk_AHDR(self, offset, nbytes):
"AHDR -- animation header"
# assertions
if self.count != 0:
raise SyntaxError("misplaced AHDR chunk")
s = self.fp.read(nbytes)
self.size = i32(s), i32(s[4:])
try:
self.mode, self.rawmode = _MODES[(s[8], s[9])]
except:
raise SyntaxError("unknown ARG mode")
if Image.DEBUG:
print("AHDR size", self.size)
print("AHDR mode", self.mode, self.rawmode)
return s
def chunk_PAST(self, offset, nbytes):
"PAST -- paste one image into another"
# assertions
if self.count == 0:
raise SyntaxError("misplaced PAST chunk")
if self.repair is not None:
# we must repair the target image before we
# start pasting
# brute force; a better solution would be to
# update only the dirty rectangles in images[id].
# note that if images[id] doesn't exist, it must
# be created
self.images[self.id] = self.images[self.repair].copy()
self.repair = None
s = self.fp.read(nbytes)
im = self.images[i16(s)]
x, y = i32(s[2:6]), i32(s[6:10])
bbox = x, y, im.size[0] + x, im.size[1] + y
if im.mode in [b"RGBA"]:
# paste with transparency
# FIXME: should handle P+transparency as well
self.images[self.id].paste(im, bbox, im)
else:
# paste without transparency
self.images[self.id].paste(im, bbox)
self.action = (b"PAST",)
self.__store()
return s