Load BytesIO image with opencv

python opencv imread
Henrique picture Henrique · Oct 7, 2017 · Viewed 15.4k times · Source

I'm trying to load an image with OPENCV from an io.BytesIO() structure. Originally, the code loads the image with PIL, like below:

image_stream = io.BytesIO()
image_stream.write(connection.read(image_len))
image_stream.seek(0)
image = Image.open(image_stream)
print('Image is %dx%d' % image.size)

I tried to open with OPENCV like that:

image_stream = io.BytesIO()
image_stream.write(connection.read(image_len))
image_stream.seek(0)
img = cv2.imread(image_stream,0)
cv2.imshow('image',img)

But it seems that imread doesn't deal with BytesIO(). I'm getting an error.

I'm using OPENCV 3.3 and Python 2.7. Please, could someone help me?

Answer

arrybn picture arrybn · Nov 20, 2017

Henrique Try this:

import numpy as np
import cv2 as cv
import io

image_stream = io.BytesIO()
image_stream.write(connection.read(image_len))
image_stream.seek(0)
file_bytes = np.asarray(bytearray(image_stream.read()), dtype=np.uint8)
img = cv.imdecode(file_bytes, cv.IMREAD_COLOR)

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