Use Rasterio to create webp

[vincentsarago]

in

rio-rgbify/rio_rgbify/mbtiler.py

Lines 46 to 69 in 31bd65b

	def _encode_as_webp(data, profile=None, affine=None):
	"""
	Uses BytesIO + PIL to encode a (3, 512, 512)
	array into a webp bytearray.
	Parameters
	-----------
	data: ndarray
	(3 x 512 x 512) uint8 RGB array
	profile: None
	ignored
	affine: None
	ignored
	Returns
	--------
	contents: bytearray
	webp-encoded bytearray of the provided input data
	"""
	with BytesIO() as f:
	im = Image.fromarray(np.rollaxis(data, 0, 3))
	im.save(f, format='webp', lossless=True)
	return f.getvalue()

we use Pillow to save the image as webp. Since rasterio ~1.0.9 , rasterio wheels are shipped with Webp driver so we could use rasterio instead of PIL and save on the dependency ;-)

cc @dnomadb

[dnomadb]

@vincentsarago I'm not seeing exactly how to create lossless webps -- is it is simple as setting lossless=True in the rasterio creation kwargs?

Also FWIW we should probably refactor this anyways as it was written before rasterio MemoryFiles were introduced.

rio-rgbify/rio_rgbify/mbtiler.py

Line 93 in 31bd65b

with rasterio.open('/vsimem/tileimg', 'w', **profile) as dst:

Looking forward to the PR!

[vincentsarago]

is it is simple as setting lossless=True in the rasterio creation kwargs?

I think yes, https://github.com/cogeotiff/rio-tiler/blob/master/rio_tiler/profiles.py#L24-L27

Also FWIW we should probably refactor this anyways as it was written before rasterio MemoryFiles were introduced.

👌

Looking forward to the PR!

🤔 sure when you'll merge #18

[vincentsarago]

I'll take care of this issue after #24 ;-)

[kylebarron]

@vincentsarago Now that #24 is merged, is this PR still valid?