Can support for the memoryview type be added as input to _decode (decode.c)?

[bigcat88]

Data created with help of PyMemoryView_FromMemory function.

Overhead for big images when converting memoryview to bytes is noticeable.

Code located here:

Pillow/src/decode.c

Line 124 in 7e3bed6

if (!PyArg_ParseTuple(args, "y#", &buffer, &bufsize)) {

Is this possible to easy add support for such feature or not?

[radarhere]

If I understand correctly, you're asking for a modification to the C API? This has nothing to do with the Python interface of Pillow?

#4532 (comment)

Pillow makes a commitment to stable public interfaces, which are defined at the Python layer. The C interfaces are explicitly internal, and no effort is made to keep them stable even between minor releases, and no support or warning is given when they change. (IIRC, there are/were people using the internal interfaces, but they've always been explicitly on their own with that)

[bigcat88]

I'm asking for Image.frombytes method to accept memoryview type for data in addition to bytes, when decoder_name="raw".

Pillow/src/PIL/Image.py

Lines 806 to 832 in 7e3bed6

	def frombytes(self, data, decoder_name="raw", *args):
	"""
	Loads this image with pixel data from a bytes object.
	This method is similar to the :py:func:`~PIL.Image.frombytes` function,
	but loads data into this image instead of creating a new image object.
	"""
	# may pass tuple instead of argument list
	if len(args) == 1 and isinstance(args[0], tuple):
	args = args[0]
	# default format
	if decoder_name == "raw" and args == ():
	args = self.mode
	# unpack data
	d = _getdecoder(self.mode, decoder_name, args)
	d.setimage(self.im)
	s = d.decode(data)
	if s[0] >= 0:
	msg = "not enough image data"
	raise ValueError(msg)
	if s[1] != 0:
	msg = "cannot decode image data"
	raise ValueError(msg)

It should not be very hard, I can make a PR for this if you want.

[radarhere]

Feel free to do so.

[radarhere]

#6937 or #6974 have been created as possible resolutions to this.

[mara004]

Thanks for this improvement! Seems to apply to frombuffer(), too.
It's shipped since v9.5, right?

[hugovk]

Yes, #6974 was released in https://github.com/python-pillow/Pillow/releases/tag/9.5.0.