text: # -*- coding: utf-8 -*-
  # imageio is distributed under the terms of the (new) BSD License.
  
  """
  Various utilities for imageio
  """
  
  
  from collections import OrderedDict
  import numpy as np
  import os
  import re
  import struct
  import sys
  import time
  import logging
  
  
  logger = logging.getLogger("imageio")
  
  IS_PYPY = "__pypy__" in sys.builtin_module_names
  THIS_DIR = os.path.abspath(os.path.dirname(__file__))
  
  
  def urlopen(*args, **kwargs):
      """Compatibility function for the urlopen function. Raises an
      RuntimeError if urlopen could not be imported (which can occur in
      frozen applications.
      """
      try:
          from urllib.request import urlopen
      except ImportError:
          raise RuntimeError("Could not import urlopen.")
      return urlopen(*args, **kwargs)
  
  
  def _precision_warn(p1, p2, extra=""):
      t = (
          "Lossy conversion from {} to {}. {} Convert image to {} prior to "
          "saving to suppress this warning."
      )
      logger.warning(t.format(p1, p2, extra, p2))
  
  
  def image_as_uint(im, bitdepth=None):
      """Convert the given image to uint (default: uint8)
  
      If the dtype already matches the desired format, it is returned
      as-is. If the image is float, and all values are between 0 and 1,
      the values are multiplied by np.power(2.0, bitdepth). In all other
      situations, the values are scaled such that the minimum value
      becomes 0 and the maximum value becomes np.power(2.0, bitdepth)-1
      (255 for 8-bit and 65535 for 16-bit).
      """
      if not bitdepth:
          bitdepth = 8
      if not isinstance(im, np.ndarray):
          raise ValueError("Image must be a numpy array")
      if bitdepth == 8:
          out_type = np.uint8
      elif bitdepth == 16:
          out_type = np.uint16
      else:
          raise ValueError("Bitdepth must be either 8 or 16")
      dtype_str1 = str(im.dtype)
      dtype_str2 = out_type.__name__
      if (im.dtype == np.uint8 and bitdepth == 8) or (
          im.dtype == np.uint16 and bitdepth == 16
      ):
          # Already the correct format? Return as-is
          return im
      if dtype_str1.startswith("float") and np.nanmin(im) >= 0 and np.nanmax(im) <= 1:
          _precision_warn(dtype_str1, dtype_str2, "Range [0, 1].")
          im = im.astype(np.float64) * (np.power(2.0, bitdepth) - 1) + 0.499999999
      elif im.dtype == np.uint16 and bitdepth == 8:
          _precision_warn(dtype_str1, dtype_str2, "Losing 8 bits of resolution.")
          im = np.right_shift(im, 8)
      elif im.dtype == np.uint32:
          _precision_warn(
              dtype_str1,
              dtype_str2,
              "Losing {} bits of resolution.".format(32 - bitdepth),
          )
          im = np.right_shift(im, 32 - bitdepth)
      elif im.dtype == np.uint64:
          _precision_warn(
              dtype_str1,
              dtype_str2,
              "Losing {} bits of resolution.".format(64 - bitdepth),
          )
          im = np.right_shift(im, 64 - bitdepth)
      else:
          mi = np.nanmin(im)
          ma = np.nanmax(im)
          if not np.isfinite(mi):
              raise ValueError("Minimum image value is not finite")
          if not np.isfinite(ma):
              raise ValueError("Maximum image value is not finite")
          if ma == mi:
              return im.astype(out_type)
          _precision_warn(dtype_str1, dtype_str2, "Range [{}, {}].".format(mi, ma))
          # Now make float copy before we scale
          im = im.astype("float64")
          # Scale the values between 0 and 1 then multiply by the max value
          im = (im - mi) / (ma - mi) * (np.power(2.0, bitdepth) - 1) + 0.499999999
      assert np.nanmin(im) >= 0
      assert np.nanmax(im) < np.power(2.0, bitdepth)
      return im.astype(out_type)
  
  
  class Array(np.ndarray):
      """Array(array, meta=None)
  
      A subclass of np.ndarray that has a meta attribute. Get the dictionary
      that contains the meta data using ``im.meta``. Convert to a plain numpy
      array using ``np.asarray(im)``.
  
      """
  
      def __new__(cls, array, meta=None):
          # Check
          if not isinstance(array, np.ndarray):
              raise ValueError("Array expects a numpy array.")
          if not (meta is None or isinstance(meta, dict)):
              raise ValueError("Array expects meta data to be a dict.")
          # Convert and return
          meta = meta if meta is not None else getattr(array, "meta", {})
          try:
              ob = array.view(cls)
          except AttributeError:  # pragma: no cover
              # Just return the original; no metadata on the array in Pypy!
              return array
          ob._copy_meta(meta)
          return ob
  
      def _copy_meta(self, meta):
          """Make a 2-level deep copy of the meta dictionary."""
          self._meta = Dict()
          for key, val in meta.items():
              if isinstance(val, dict):
                  val = Dict(val)  # Copy this level
              self._meta[key] = val
  
      @property
      def meta(self):
          """The dict with the meta data of this image."""
          return self._meta
  
      def __array_finalize__(self, ob):
          """So the meta info is maintained when doing calculations with
          the array.
          """
          if isinstance(ob, Array):
              self._copy_meta(ob.meta)
          else:
              self._copy_meta({})
  
      def __array_wrap__(self, out, context=None):
          """So that we return a native numpy array (or scalar) when a
          reducting ufunc is applied (such as sum(), std(), etc.)
          """
          if not out.shape:
              return out.dtype.type(out)  # Scalar
          elif out.shape != self.shape:
              return out.view(type=np.ndarray)
          else:
              return out  # Type Array
  
  
  Image = Array  # Alias for backwards compatibility
  
  
  def asarray(a):
      """Pypy-safe version of np.asarray. Pypy's np.asarray consumes a
      *lot* of memory if the given array is an ndarray subclass. This
      function does not.
      """
      if isinstance(a, np.ndarray):
          if IS_PYPY:  # pragma: no cover
              a = a.copy()  # pypy has issues with base views
          plain = a.view(type=np.ndarray)
          return plain
      return np.asarray(a)
  
  
  class Dict(OrderedDict):
      """A dict in which the keys can be get and set as if they were
      attributes. Very convenient in combination with autocompletion.
  
      This Dict still behaves as much as possible as a normal dict, and
      keys can be anything that are otherwise valid keys. However,
      keys that are not valid identifiers or that are names of the dict
      class (such as 'items' and 'copy') cannot be get/set as attributes.
      """
  
      __reserved_names__ = dir(OrderedDict())  # Also from OrderedDict
      __pure_names__ = dir(dict())
  
      def __getattribute__(self, key):
          try:
              return object.__getattribute__(self, key)
          except AttributeError:
              if key in self:
                  return self[key]
              else:
                  raise
  
      def __setattr__(self, key, val):
          if key in Dict.__reserved_names__:
              # Either let OrderedDict do its work, or disallow
              if key not in Dict.__pure_names__:
                  return OrderedDict.__setattr__(self, key, val)
              else:
                  raise AttributeError(
                      "Reserved name, this key can only "
                      + "be set via ``d[%r] = X``" % key
                  )
          else:
              # if isinstance(val, dict): val = Dict(val) -> no, makes a copy!
              self[key] = val
  
      def __dir__(self):
          def isidentifier(x):
              return bool(re.match(r"[a-z_]\w*$", x, re.I))
  
          names = [k for k in self.keys() if (isinstance(k, str) and isidentifier(k))]
          return Dict.__reserved_names__ + names
  
  
  class BaseProgressIndicator(object):
      """BaseProgressIndicator(name)
  
      A progress indicator helps display the progres of a task to the
      user. Progress can be pending, running, finished or failed.
  
      Each task has:
        * a name - a short description of what needs to be done.
        * an action - the current action in performing the task (e.g. a subtask)
        * progress - how far the task is completed
        * max - max number of progress units. If 0, the progress is indefinite
        * unit - the units in which the progress is counted
        * status - 0: pending, 1: in progress, 2: finished, 3: failed
  
      This class defines an abstract interface. Subclasses should implement
      _start, _stop, _update_progress(progressText), _write(message).
      """
  
      def __init__(self, name):
          self._name = name
          self._action = ""
          self._unit = ""
          self._max = 0
          self._status = 0
          self._last_progress_update = 0
  
      def start(self, action="", unit="", max=0):
          """start(action='', unit='', max=0)
  
          Start the progress. Optionally specify an action, a unit,
          and a maxium progress value.
          """
          if self._status == 1:
              self.finish()
          self._action = action
          self._unit = unit
          self._max = max
          #
          self._progress = 0
          self._status = 1
          self._start()
  
      def status(self):
          """status()
  
          Get the status of the progress - 0: pending, 1: in progress,
          2: finished, 3: failed
          """
          return self._status
  
      def set_progress(self, progress=0, force=False):
          """set_progress(progress=0, force=False)
  
          Set the current progress. To avoid unnecessary progress updates
          this will only have a visual effect if the time since the last
          update is > 0.1 seconds, or if force is True.
          """
          self._progress = progress
          # Update or not?
          if not (force or (time.time() - self._last_progress_update > 0.1)):
              return
          self._last_progress_update = time.time()
          # Compose new string
          unit = self._unit or ""
          progressText = ""
          if unit == "%":
              progressText = "%2.1f%%" % progress
          elif self._max > 0:
              percent = 100 * float(progress) / self._max
              progressText = "%i/%i %s (%2.1f%%)" % (progress, self._max, unit, percent)
          elif progress > 0:
              if isinstance(progress, float):
                  progressText = "%0.4g %s" % (progress, unit)
              else:
                  progressText = "%i %s" % (progress, unit)
          # Update
          self._update_progress(progressText)
  
      def increase_progress(self, extra_progress):
          """increase_progress(extra_progress)
  
          Increase the progress by a certain amount.
          """
          self.set_progress(self._progress + extra_progress)
  
      def finish(self, message=None):
          """finish(message=None)
  
          Finish the progress, optionally specifying a message. This will
          not set the progress to the maximum.
          """
          self.set_progress(self._progress, True)  # fore update
          self._status = 2
          self._stop()
          if message is not None:
              self._write(message)
  
      def fail(self, message=None):
          """fail(message=None)
  
          Stop the progress with a failure, optionally specifying a message.
          """
          self.set_progress(self._progress, True)  # fore update
          self._status = 3
          self._stop()
          message = "FAIL " + (message or "")
          self._write(message)
  
      def write(self, message):
          """write(message)
  
          Write a message during progress (such as a warning).
          """
          if self.__class__ == BaseProgressIndicator:
              # When this class is used as a dummy, print explicit message
              print(message)
          else:
              return self._write(message)
  
      # Implementing classes should implement these
  
      def _start(self):
          pass
  
      def _stop(self):
          pass
  
      def _update_progress(self, progressText):
          pass
  
      def _write(self, message):
          pass
  
  
  class StdoutProgressIndicator(BaseProgressIndicator):
      """StdoutProgressIndicator(name)
  
      A progress indicator that shows the progress in stdout. It
      assumes that the tty can appropriately deal with backspace
      characters.
      """
  
      def _start(self):
          self._chars_prefix, self._chars = "", ""
          # Write message
          if self._action:
              self._chars_prefix = "%s (%s): " % (self._name, self._action)
          else:
              self._chars_prefix = "%s: " % self._name
          sys.stdout.write(self._chars_prefix)
          sys.stdout.flush()
  
      def _update_progress(self, progressText):
          # If progress is unknown, at least make something move
          if not progressText:
              i1, i2, i3, i4 = "-\\|/"
              M = {i1: i2, i2: i3, i3: i4, i4: i1}
              progressText = M.get(self._chars, i1)
          # Store new string and write
          delChars = "\b" * len(self._chars)
          self._chars = progressText
          sys.stdout.write(delChars + self._chars)
          sys.stdout.flush()
  
      def _stop(self):
          self._chars = self._chars_prefix = ""
          sys.stdout.write("\n")
          sys.stdout.flush()
  
      def _write(self, message):
          # Write message
          delChars = "\b" * len(self._chars_prefix + self._chars)
          sys.stdout.write(delChars + "  " + message + "\n")
          # Reprint progress text
          sys.stdout.write(self._chars_prefix + self._chars)
          sys.stdout.flush()
  
  
  # From pyzolib/paths.py (https://bitbucket.org/pyzo/pyzolib/src/tip/paths.py)
  def appdata_dir(appname=None, roaming=False):
      """appdata_dir(appname=None, roaming=False)
  
      Get the path to the application directory, where applications are allowed
      to write user specific files (e.g. configurations). For non-user specific
      data, consider using common_appdata_dir().
      If appname is given, a subdir is appended (and created if necessary).
      If roaming is True, will prefer a roaming directory (Windows Vista/7).
      """
  
      # Define default user directory
      userDir = os.getenv("IMAGEIO_USERDIR", None)
      if userDir is None:
          userDir = os.path.expanduser("~")
          if not os.path.isdir(userDir):  # pragma: no cover
              userDir = "/var/tmp"  # issue #54
  
      # Get system app data dir
      path = None
      if sys.platform.startswith("win"):
          path1, path2 = os.getenv("LOCALAPPDATA"), os.getenv("APPDATA")
          path = (path2 or path1) if roaming else (path1 or path2)
      elif sys.platform.startswith("darwin"):
          path = os.path.join(userDir, "Library", "Application Support")
      # On Linux and as fallback
      if not (path and os.path.isdir(path)):
          path = userDir
  
      # Maybe we should store things local to the executable (in case of a
      # portable distro or a frozen application that wants to be portable)
      prefix = sys.prefix
      if getattr(sys, "frozen", None):
          prefix = os.path.abspath(os.path.dirname(sys.executable))
      for reldir in ("settings", "../settings"):
          localpath = os.path.abspath(os.path.join(prefix, reldir))
          if os.path.isdir(localpath):  # pragma: no cover
              try:
                  open(os.path.join(localpath, "test.write"), "wb").close()
                  os.remove(os.path.join(localpath, "test.write"))
              except IOError:
                  pass  # We cannot write in this directory
              else:
                  path = localpath
                  break
  
      # Get path specific for this app
      if appname:
          if path == userDir:
              appname = "." + appname.lstrip(".")  # Make it a hidden directory
          path = os.path.join(path, appname)
          if not os.path.isdir(path):  # pragma: no cover
              os.makedirs(path, exist_ok=True)
  
      # Done
      return path
  
  
  def resource_dirs():
      """resource_dirs()
  
      Get a list of directories where imageio resources may be located.
      The first directory in this list is the "resources" directory in
      the package itself. The second directory is the appdata directory
      (~/.imageio on Linux). The list further contains the application
      directory (for frozen apps), and may include additional directories
      in the future.
      """
      dirs = [resource_package_dir()]
      # Resource dir baked in the package.
      # Appdata directory
      try:
          dirs.append(appdata_dir("imageio"))
      except Exception:  # pragma: no cover
          pass  # The home dir may not be writable
      # Directory where the app is located (mainly for frozen apps)
      if getattr(sys, "frozen", None):
          dirs.append(os.path.abspath(os.path.dirname(sys.executable)))
      elif sys.path and sys.path[0]:
          dirs.append(os.path.abspath(sys.path[0]))
      return dirs
  
  
  def resource_package_dir():
      """package_dir
  
      Get the resources directory in the imageio package installation
      directory.
  
      Notes
      -----
      This is a convenience method that is used by `resource_dirs` and
      imageio entry point scripts.
      """
      # Make pkg_resources optional if setuptools is not available
      try:
          # Avoid importing pkg_resources in the top level due to how slow it is
          # https://github.com/pypa/setuptools/issues/510
          import pkg_resources
      except ImportError:
          pkg_resources = None
  
      if pkg_resources:
          # The directory returned by `pkg_resources.resource_filename`
          # also works with eggs.
          pdir = pkg_resources.resource_filename("imageio", "resources")
      else:
          # If setuptools is not available, use fallback
          pdir = os.path.abspath(os.path.join(THIS_DIR, "..", "resources"))
      return pdir
  
  
  def get_platform():
      """get_platform()
  
      Get a string that specifies the platform more specific than
      sys.platform does. The result can be: linux32, linux64, win32,
      win64, osx32, osx64. Other platforms may be added in the future.
      """
      # Get platform
      if sys.platform.startswith("linux"):
          plat = "linux%i"
      elif sys.platform.startswith("win"):
          plat = "win%i"
      elif sys.platform.startswith("darwin"):
          plat = "osx%i"
      elif sys.platform.startswith("freebsd"):
          plat = "freebsd%i"
      else:  # pragma: no cover
          return None
  
      return plat % (struct.calcsize("P") * 8)  # 32 or 64 bits
  
  
  def has_module(module_name):
      """Check to see if a python module is available."""
      if sys.version_info > (3, 4):
          import importlib
  
          name_parts = module_name.split(".")
          for i in range(len(name_parts)):
              if importlib.util.find_spec(".".join(name_parts[: i + 1])) is None:
                  return False
          return True
      else:  # pragma: no cover
          import imp
  
          try:
              imp.find_module(module_name)
          except ImportError:
              return False
          return True
  