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does cv2.imwrite support float16 (half)?

import cv2 as cv
import random
import numpy as np

# Reading an existing exr file
img = cv.imread('Tree.exr', cv.IMREAD_UNCHANGED)
print (img.dtype)      \\ this prints float32

img_h = np.float16(img)     \\ hoping to typecast float32(float) to float16 (half)
print (img_h.dtype)     \\ this prints float16

#cv.imwrite('cropped_tree.exr', img)                 #this works fine write float32 into exr
#cv.imwrite('cropped_tree.exr', img, cv.IMWRITE_EXR_TYPE_FLOAT)      # this doesn't work, gives: 
#     cv.imwrite('cropped_tree.exr', img, cv.IMWRITE_EXR_TYPE_FLOAT)
#     SystemError: <built-in function imwrite> returned NULL without setting an error
 cv.imwrite('cropped_tree.exr', img_h, cv.IMWRITE_EXR_TYPE_HALF)   # this doesn't work, gives :
#     cv.imwrite('cropped_tree.exr', img_h, cv.IMWRITE_EXR_TYPE_HALF)
#     TypeError: img data type = 23 is not supported

Python version = 3.6 numpy version = 1.14.5 opencv-python = 3.4.1.15 also tried on other pc with opencv = 3.4.1

the problem seems like opencv doesn't support fp16 even though documentation says so. Also am I using the imwrite function properly?

does cv2.imwrite support float16 (half)?

import cv2 as cv
import random
import numpy as np

# Reading an existing exr file
img = cv.imread('Tree.exr', cv.IMREAD_UNCHANGED)
print (img.dtype)      \\ this prints float32

img_h = np.float16(img)     \\ hoping to typecast float32(float) to float16 (half)
print (img_h.dtype)     \\ this prints float16

#cv.imwrite('cropped_tree.exr', img)                 #this works fine write float32 into exr
#cv.imwrite('cropped_tree.exr', img, cv.IMWRITE_EXR_TYPE_FLOAT)      # this doesn't work, gives: 
#     cv.imwrite('cropped_tree.exr', img, cv.IMWRITE_EXR_TYPE_FLOAT)
#     SystemError: <built-in function imwrite> returned NULL without setting an error
 cv.imwrite('cropped_tree.exr', img_h, cv.IMWRITE_EXR_TYPE_HALF)   # this doesn't work, gives :
#     cv.imwrite('cropped_tree.exr', img_h, cv.IMWRITE_EXR_TYPE_HALF)
#     TypeError: img data type = 23 is not supported

Python version = 3.6 numpy version = 1.14.5 opencv-python = 3.4.1.15 also tried on other pc with opencv = 3.4.1

the problem seems like opencv doesn't support fp16 even though documentation says so. Also am I using the imwrite function properly?

does cv2.imwrite support float16 (half)?

import cv2 as cv
import random
import numpy as np

# Reading an existing exr file
img = cv.imread('Tree.exr', cv.IMREAD_UNCHANGED)
print (img.dtype)      \\ this prints float32

img_h = np.float16(img)     \\ hoping to typecast float32(float) to float16 (half)
print (img_h.dtype)     \\ this prints float16

#cv.imwrite('cropped_tree.exr', img)                 #this works fine write float32 into exr
#cv.imwrite('cropped_tree.exr', img, cv.IMWRITE_EXR_TYPE_FLOAT)      # this doesn't work, gives: 
#     cv.imwrite('cropped_tree.exr', img, cv.IMWRITE_EXR_TYPE_FLOAT)
#     SystemError: <built-in function imwrite> returned NULL without setting an error
 cv.imwrite('cropped_tree.exr', img_h, cv.IMWRITE_EXR_TYPE_HALF)   # this doesn't work, gives :
#     cv.imwrite('cropped_tree.exr', img_h, cv.IMWRITE_EXR_TYPE_HALF)
#     TypeError: img data type = 23 is not supported

Python version = 3.6 numpy version = 1.14.5 opencv-python = 3.4.1.15 also tried on other pc with opencv = 3.4.1

the problem seems like opencv doesn't support fp16 even though documentation says so. Also am I using the imwrite function properly?