Fixed database typo and removed unnecessary class identifier.

venv/Lib/site-packages/imageio/plugins/example.py

@@ -0,0 +1,148 @@
+# -*- coding: utf-8 -*-
+# imageio is distributed under the terms of the (new) BSD License.
+
+""" Example plugin. You can use this as a template for your own plugin.
+"""
+
+import numpy as np
+
+from .. import formats
+from ..core import Format
+
+
+class DummyFormat(Format):
+    """ The dummy format is an example format that does nothing.
+    It will never indicate that it can read or write a file. When
+    explicitly asked to read, it will simply read the bytes. When
+    explicitly asked to write, it will raise an error.
+
+    This documentation is shown when the user does ``help('thisformat')``.
+
+    Parameters for reading
+    ----------------------
+    Specify arguments in numpy doc style here.
+
+    Parameters for saving
+    ---------------------
+    Specify arguments in numpy doc style here.
+
+    """
+
+    def _can_read(self, request):
+        # This method is called when the format manager is searching
+        # for a format to read a certain image. Return True if this format
+        # can do it.
+        #
+        # The format manager is aware of the extensions and the modes
+        # that each format can handle. It will first ask all formats
+        # that *seem* to be able to read it whether they can. If none
+        # can, it will ask the remaining formats if they can: the
+        # extension might be missing, and this allows formats to provide
+        # functionality for certain extensions, while giving preference
+        # to other plugins.
+        #
+        # If a format says it can, it should live up to it. The format
+        # would ideally check the request.firstbytes and look for a
+        # header of some kind.
+        #
+        # The request object has:
+        # request.filename: a representation of the source (only for reporting)
+        # request.firstbytes: the first 256 bytes of the file.
+        # request.mode[0]: read or write mode
+        # request.mode[1]: what kind of data the user expects: one of 'iIvV?'
+
+        if request.mode[1] in (self.modes + "?"):
+            if request.extension in self.extensions:
+                return True
+
+    def _can_write(self, request):
+        # This method is called when the format manager is searching
+        # for a format to write a certain image. It will first ask all
+        # formats that *seem* to be able to write it whether they can.
+        # If none can, it will ask the remaining formats if they can.
+        #
+        # Return True if the format can do it.
+
+        # In most cases, this code does suffice:
+        if request.mode[1] in (self.modes + "?"):
+            if request.extension in self.extensions:
+                return True
+
+    # -- reader
+
+    class Reader(Format.Reader):
+        def _open(self, some_option=False, length=1):
+            # Specify kwargs here. Optionally, the user-specified kwargs
+            # can also be accessed via the request.kwargs object.
+            #
+            # The request object provides two ways to get access to the
+            # data. Use just one:
+            #  - Use request.get_file() for a file object (preferred)
+            #  - Use request.get_local_filename() for a file on the system
+            self._fp = self.request.get_file()
+            self._length = length  # passed as an arg in this case for testing
+            self._data = None
+
+        def _close(self):
+            # Close the reader.
+            # Note that the request object will close self._fp
+            pass
+
+        def _get_length(self):
+            # Return the number of images. Can be np.inf
+            return self._length
+
+        def _get_data(self, index):
+            # Return the data and meta data for the given index
+            if index >= self._length:
+                raise IndexError("Image index %i > %i" % (index, self._length))
+            # Read all bytes
+            if self._data is None:
+                self._data = self._fp.read()
+            # Put in a numpy array
+            im = np.frombuffer(self._data, "uint8")
+            im.shape = len(im), 1
+            # Return array and dummy meta data
+            return im, {}
+
+        def _get_meta_data(self, index):
+            # Get the meta data for the given index. If index is None, it
+            # should return the global meta data.
+            return {}  # This format does not support meta data
+
+    # -- writer
+
+    class Writer(Format.Writer):
+        def _open(self, flags=0):
+            # Specify kwargs here. Optionally, the user-specified kwargs
+            # can also be accessed via the request.kwargs object.
+            #
+            # The request object provides two ways to write the data.
+            # Use just one:
+            #  - Use request.get_file() for a file object (preferred)
+            #  - Use request.get_local_filename() for a file on the system
+            self._fp = self.request.get_file()
+
+        def _close(self):
+            # Close the reader.
+            # Note that the request object will close self._fp
+            pass
+
+        def _append_data(self, im, meta):
+            # Process the given data and meta data.
+            raise RuntimeError("The dummy format cannot write image data.")
+
+        def set_meta_data(self, meta):
+            # Process the given meta data (global for all images)
+            # It is not mandatory to support this.
+            raise RuntimeError("The dummy format cannot write meta data.")
+
+
+# Register. You register an *instance* of a Format class. Here specify:
+format = DummyFormat(
+    "dummy",  # short name
+    "An example format that does nothing.",  # one line descr.
+    ".foobar .nonexistentext",  # list of extensions
+    "iI",  # modes, characters in iIvV
+)
+formats.add_format(format)