Reading .exr Files In Opencv

I have generated some depth maps using blender and have saved z-buffer values(32 bits) in OpenEXR format. Is there any way to access values from a .exr file (pixel by pixel depth i

Solution 1:

I might be a little late to the party but; Yes you can definitely use OpenCV for that.

cv2.imread(PATH_TO_EXR_FILE,  cv2.IMREAD_ANYCOLOR | cv2.IMREAD_ANYDEPTH)  

should get you what you need

Solution 2:

You can use OpenEXR package

pip --no-cache-dir install OpenEXR

If the above fails, install the OpenEXR dev library and then install the python package as above

sudo apt-get install libopenexr-dev

To read exr file

def read_depth_exr_file(filepath: Path):
    exrfile = exr.InputFile(filepath.as_posix())
    raw_bytes = exrfile.channel('B', Imath.PixelType(Imath.PixelType.FLOAT))
    depth_vector = numpy.frombuffer(raw_bytes, dtype=numpy.float32)
    height = exrfile.header()['displayWindow'].max.y + 1 - exrfile.header()['displayWindow'].min.y
    width = exrfile.header()['displayWindow'].max.x + 1 - exrfile.header()['displayWindow'].min.x
    depth_map = numpy.reshape(depth_vector, (height, width))
    return depth_map