Python Image._getdecoder方法代码示例

# 需要导入模块: from reqs.pil import Image [as 别名]
# 或者: from reqs.pil.Image import _getdecoder [as 别名]
    def feed(self, data):
        # collect data

        if self.finished:
            return

        if self.data is None:
            self.data = data
        else:
            self.data = self.data + data

        # parse what we have
        if self.decoder:

            if self.offset > 0:
                # skip header
                skip = min(len(self.data), self.offset)
                self.data = self.data[skip:]
                self.offset = self.offset - skip
                if self.offset > 0 or not self.data:
                    return

            n, e = self.decoder.decode(self.data)

            if n < 0:
                # end of stream
                self.data = None
                self.finished = 1
                if e < 0:
                    # decoding error
                    self.image = None
                    raise_ioerror(e)
                else:
                    # end of image
                    return
            self.data = self.data[n:]

        elif self.image:

            # if we end up here with no decoder, this file cannot
            # be incrementally parsed.  wait until we've gotten all
            # available data
            pass

        else:

            # attempt to open this file
            try:
                try:
                    fp = _ParserFile(self.data)
                    im = Image.open(fp)
                finally:
                    fp.close() # explicitly close the virtual file
            except IOError:
                pass # not enough data
            else:
                flag = hasattr(im, "load_seek") or hasattr(im, "load_read")
                if flag or len(im.tile) != 1:
                    # custom load code, or multiple tiles
                    self.decode = None
                else:
                    # initialize decoder
                    im.load_prepare()
                    d, e, o, a = im.tile[0]
                    im.tile = []
                    self.decoder = Image._getdecoder(
                        im.mode, d, a, im.decoderconfig
                        )
                    self.decoder.setimage(im.im, e)

                    # calculate decoder offset
                    self.offset = o
                    if self.offset <= len(self.data):
                        self.data = self.data[self.offset:]
                        self.offset = 0

                self.image = im

# 需要导入模块: from reqs.pil import Image [as 别名]
# 或者: from reqs.pil.Image import _getdecoder [as 别名]
    def load(self):
        "Load image data based on tile list"

        pixel = Image.Image.load(self)

        if self.tile is None:
            raise IOError("cannot load this image")
        if not self.tile:
            return pixel

        self.map = None

        readonly = 0

        if self.filename and len(self.tile) == 1:
            # try memory mapping
            d, e, o, a = self.tile[0]
            if d == "raw" and a[0] == self.mode and a[0] in Image._MAPMODES:
                try:
                    if hasattr(Image.core, "map"):
                        # use built-in mapper
                        self.map = Image.core.map(self.filename)
                        self.map.seek(o)
                        self.im = self.map.readimage(
                            self.mode, self.size, a[1], a[2]
                            )
                    else:
                        # use mmap, if possible
                        import mmap
                        file = open(self.filename, "r+")
                        size = os.path.getsize(self.filename)
                        # FIXME: on Unix, use PROT_READ etc
                        self.map = mmap.mmap(file.fileno(), size)
                        self.im = Image.core.map_buffer(
                            self.map, self.size, d, e, o, a
                            )
                    readonly = 1
                except (AttributeError, EnvironmentError, ImportError):
                    self.map = None

        self.load_prepare()

        # look for read/seek overrides
        try:
            read = self.load_read
        except AttributeError:
            read = self.fp.read

        try:
            seek = self.load_seek
        except AttributeError:
            seek = self.fp.seek

        if not self.map:

            # sort tiles in file order
            self.tile.sort(_tilesort)

            try:
                # FIXME: This is a hack to handle TIFF's JpegTables tag.
                prefix = self.tile_prefix
            except AttributeError:
                prefix = ""

            for d, e, o, a in self.tile:
                d = Image._getdecoder(self.mode, d, a, self.decoderconfig)
                seek(o)
                try:
                    d.setimage(self.im, e)
                except ValueError:
                    continue
                b = prefix
                t = len(b)
                while 1:
                    s = read(self.decodermaxblock)
                    if not s:
                        self.tile = []
                        raise IOError("image file is truncated (%d bytes not processed)" % len(b))
                    b = b + s
                    n, e = d.decode(b)
                    if n < 0:
                        break
                    b = b[n:]
                    t = t + n

        self.tile = []
        self.readonly = readonly

        self.fp = None # might be shared

        if not self.map and e < 0:
            raise_ioerror(e)

        # post processing
        if hasattr(self, "tile_post_rotate"):
            # FIXME: This is a hack to handle rotated PCD's
            self.im = self.im.rotate(self.tile_post_rotate)
            self.size = self.im.size

        self.load_end()
#.........这里部分代码省略.........