Use imageio instead of opencv to load images

bob/io/stream/test/test_streams.py

@@ -7,13 +7,12 @@ Test Units
 # ==============================================================================
 import os
 import datetime
-
+import imageio as iio
 import numpy as np
-import cv2 as cv
 
 from pkg_resources import resource_filename
 
-from bob.io.image import opencvbgr_to_bob
+from bob.io.image import to_bob
 
 from bob.io.stream import StreamFile, Stream
 from bob.io.stream.metadata import MetaDatum, MetaData, MetaDataInfo
@@ -191,8 +190,8 @@ def test_stream():
 def test_filters():
     """Test that a few filters provide a similar result to saved groundtruth."""
     # load groundtruth for images
-    gt_colormap_gray = opencvbgr_to_bob(cv.imread(resource_path("test/data/gt_colormap_gray.png")))
-    gt_colormap_bone = opencvbgr_to_bob(cv.imread(resource_path("test/data/gt_colormap_bone.png")))
+    gt_colormap_gray = to_bob(iio.imread(resource_path("test/data/gt_colormap_gray.png")))[:3]  # ignore alpha channel
+    gt_colormap_bone = to_bob(iio.imread(resource_path("test/data/gt_colormap_bone.png")))[:3]
     gt_right_clean = np.load(resource_path("test/data/gt_right_clean.npy"))
     gt_color_lightning_subtract_color_dark = np.load(
         resource_path("test/data/gt_color_lightning_subtract_color_dark.npy")
@@ -218,8 +217,6 @@ def test_filters():
         # adjust
         left_third = left[::3]
         left_fith = left[::5]
-        left_third.set_metadata(stream_metadata, metadata_info)
-        left_fith.set_metadata(stream_metadata, metadata_info)
         left_fith_adjust = left_fith.adjust(left_third)
 
         assert np.array_equal(left_third.metadata("timestamps"), left_fith_adjust.metadata("timestamps"))