def write_to_buffer(self, format_string, **kwargs):
"""Write an image to memory.
This method can save images in any format supported by vips. The format
is selected from the suffix in the format string. This can include
embedded save options, see :func:`Image.new_from_file`.
For example::
data = image.write_to_buffer('.jpg[Q=95]')
You can also supply options as keyword arguments, for example::
data = image.write_to_buffer('.jpg', Q=95)
The full set of options available depend upon the load operation that
will be executed. Try something like::
$ vips jpegsave_buffer
at the command-line to see a summary of the available options for the
JPEG saver.
Args:
format_string (str): The suffix, plus any string-form arguments.
Other arguments depend upon the save operation.
Returns:
A byte string.
Raises:
:class:`.Error`
"""
format_string = _to_bytes(format_string)
options = vips_lib.vips_filename_get_options(format_string)
name = vips_lib.vips_foreign_find_save_buffer(format_string)
if name == ffi.NULL:
raise Error('unable to write to buffer')
return pyvips.Operation.call(_to_string(ffi.string(name)),
self,
string_options=_to_string(
ffi.string(options)),
**kwargs)
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 damaged image.
Returns:
A new :class:`.Image`.
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_load(vips_filename)
if pointer == ffi.NULL:
raise Error('unable to load from file {0}'.format(vips_filename))
name = _to_string(pointer)
return pyvips.Operation.call(name,
filename,
string_options=options,
**kwargs)