def test_can_read_frames_randomly(self, fxt_sample_video):
video = Video(fxt_sample_video)
on_exit_do(video.close)
for idx in {1, 3, 2, 0, 3}:
frame = video[idx]
assert frame.index == idx
assert np.array_equal(frame.data,
np.ones((*video.frame_size, 3)) * idx)
def test_can_skip_from_end(self, fxt_sample_video):
video = Video(fxt_sample_video, end_frame=2)
on_exit_do(video.close)
last_frame = None
for last_frame in video:
pass
assert 2 == video.length
assert 1 == last_frame.index
def test_can_init_frame_count_lazily(self, fxt_sample_video):
video = Video(fxt_sample_video)
on_exit_do(video.close)
assert None is video.length
for idx, frame in enumerate(video):
assert idx == frame.index
assert 4 == video.length
def test_can_read_frames_sequentially(self, fxt_sample_video):
video = Video(fxt_sample_video)
on_exit_do(video.close)
for idx, frame in enumerate(video):
assert frame.size == video.frame_size
assert frame.index == idx
assert frame.video is video
assert np.array_equal(frame.data,
np.ones((*video.frame_size, 3)) * idx)
def test_can_split_video(self):
on_exit_do(MediaManager.get_instance().clear)
test_dir = scope_add(TestDir())
video_path = osp.join(test_dir, 'video.avi')
make_sample_video(video_path, frames=10)
output_dir = osp.join(test_dir, 'result')
run(TestCase(), 'util', 'split_video',
'-i', video_path, '-o', output_dir, '--image-ext', '.jpg',
'--start-frame', '2', '--end-frame', '8', '--step', '2')
assert set(os.listdir(output_dir)) == {'%06d.jpg' % n
for n in range(2, 8, 2)}
def make_sample_video(path, frames=4, frame_size=(10, 20), fps=25.0):
"""
frame_size is (H, W), only even sides
"""
writer = cv2.VideoWriter(path,
frameSize=tuple(frame_size[::-1]),
fps=float(fps),
fourcc=cv2.VideoWriter_fourcc(*'MJPG'))
on_exit_do(writer.release)
for i in range(frames):
# Apparently, only uint8 values are supported, but not floats
# Colors are compressed, but grayscale colors suffer no loss
writer.write(np.ones((*frame_size, 3), dtype=np.uint8) * i)
def test_can_read_frames(self, fxt_sample_video):
on_exit_do(MediaManager.get_instance().clear)
expected = Dataset.from_iterable([
DatasetItem('frame_%03d' % i,
subset='train',
image=np.ones((4, 6, 3)) * i) for i in range(4)
])
actual = Dataset.import_from(fxt_sample_video,
'video_frames',
subset='train',
name_pattern='frame_%03d')
compare_datasets(TestCase(), expected, actual)
def test_can_split_and_load(self, fxt_sample_video):
test_dir = scope_add(TestDir())
on_exit_do(MediaManager.get_instance().clear)
expected = Dataset.from_iterable([
DatasetItem('frame_%06d' % i, image=np.ones((4, 6, 3)) * i)
for i in range(4)
])
dataset = Dataset.import_from(fxt_sample_video,
'video_frames',
start_frame=0,
end_frame=4,
name_pattern='frame_%06d')
dataset.export(format='image_dir', save_dir=test_dir, image_ext='.jpg')
actual = Dataset.import_from(test_dir, 'image_dir')
compare_datasets(TestCase(), expected, actual)
def test_can_skip_from_start(self, fxt_sample_video):
video = Video(fxt_sample_video, start_frame=1)
on_exit_do(video.close)
assert 1 == next(iter(video)).index
def test_can_skip_frames_between(self, fxt_sample_video):
video = Video(fxt_sample_video, step=2)
on_exit_do(video.close)
for idx, frame in enumerate(video):
assert 2 * idx == frame.index
def test_can_read_video(self, fxt_sample_video):
video = Video(fxt_sample_video)
on_exit_do(video.close)
assert None is video.length
assert (4, 6) == video.frame_size
def foo():
on_error_do(error_cb)
on_exit_do(exit_cb)
raise TestException()