Ejemplo n.º 1
0
    def new_from_file(vips_filename, **kwargs):
        """Load an image from a file.

        This method can load images in any format supported by vips. The
        filename can include load options, for example::

            image = pyvips.Image.new_from_file('fred.jpg[shrink=2]')

        You can also supply options as keyword arguments, for example::

            image = pyvips.Image.new_from_file('fred.jpg', shrink=2)

        The full set of options available depend upon the load operation that
        will be executed. Try something like::

            $ vips jpegload

        at the command-line to see a summary of the available options for the
        JPEG loader.

        Loading is fast: only enough of the image is loaded to be able to fill
        out the header. Pixels will only be decompressed when they are needed.

        Args:
            vips_filename (str): The disc file to load the image from, with
                optional appended arguments.

        All loaders support at least the following options:

        Keyword args:
            memory (bool): If set True, load the image via memory rather than
                via a temporary disc file. See :meth:`.new_temp_file` for
                notes on where temporary files are created. Small images are
                loaded via memory by default, use ``VIPS_DISC_THRESHOLD`` to
                set the definition of small.
            access (Access): Hint the expected access pattern for the image.
            fail (bool): If set True, the loader will fail with an error on
                the first serious error in the file. By default, libvips
                will attempt to read everything it can from a damanged image.

        Returns:
            A new :class:`.Image`.

        Raises:
            :class:`.Error`

        """
        vips_filename = _to_bytes(vips_filename)
        filename = vips_lib.vips_filename_get_filename(vips_filename)
        options = vips_lib.vips_filename_get_options(vips_filename)
        name = vips_lib.vips_foreign_find_load(filename)
        if name == ffi.NULL:
            raise Error('unable to load from file {0}'.format(vips_filename))

        return pyvips.Operation.call(_to_string(ffi.string(name)),
                                     _to_string(ffi.string(filename)),
                                     string_options=_to_string(
                                         ffi.string(options)
                                     ), **kwargs)
Ejemplo n.º 2
0
    def write_to_file(self, vips_filename, **kwargs):
        """Write an image to a file on disc.

        This method can save images in any format supported by vips. The format
        is selected from the filename suffix. The filename can include embedded
        save options, see :func:`Image.new_from_file`.

        For example::

            image.write_to_file('fred.jpg[Q=95]')

        You can also supply options as keyword arguments, for example::

            image.write_to_file('fred.jpg', Q=95)

        The full set of options available depend upon the load operation that
        will be executed. Try something like::

            $ vips jpegsave

        at the command-line to see a summary of the available options for the
        JPEG saver.

        Args:
            vips_filename (str): The disc file to save the image to, with
                optional appended arguments.

        Other arguments depend upon the save operation.

        Returns:
            None

        Raises:
            :class:`.Error`

        """
        vips_filename = _to_bytes(vips_filename)
        pointer = vips_lib.vips_filename_get_filename(vips_filename)
        filename = _to_string_copy(pointer)

        pointer = vips_lib.vips_filename_get_options(vips_filename)
        options = _to_string_copy(pointer)

        pointer = vips_lib.vips_foreign_find_save(vips_filename)
        if pointer == ffi.NULL:
            raise Error('unable to write to file {0}'.format(vips_filename))
        name = _to_string(pointer)

        return pyvips.Operation.call(name,
                                     self,
                                     filename,
                                     string_options=options,
                                     **kwargs)