def handle_frames(self, camera_frame_files: dict, output_directory: str, display: bool = False):
for frame_idx in sorted(camera_frame_files):
# print('=== FRAME %s ===' % frame_idx)
self.current_frame = frame_idx
frame_camera_dict = camera_frame_files[frame_idx]
is_valid_frame = None
for camera, frame_file in frame_camera_dict.items():
data = json.load(open(frame_file))
data = self.frame_data_transform(data)
is_valid_frame = self.camera_frame_parse_subjects(camera, data)
if not is_valid_frame:
if self.verbose:
log('INFO', 'Not enough poses detected. Skipping camera frame')
continue
if is_valid_frame:
group_data = self.metric_intragroup_distance(self.subjects)
self.intragroup_distance = group_data
for _, subject in self.subjects.items():
if not self.has_required_cameras(subject):
log('WARN', 'Subject (%s) does not have data from required cameras. ' % subject.id +
'Not enough information to process frame (%s)' % frame_idx)
else:
self.process_subject_individual_metrics(subject,
group_data)
self.metric_overlap(self.subjects)
# writting every frame
self.save_output(output_directory, is_valid_frame)
def __init__(self,
group_id: str,
prettify: bool = False,
verbose: bool = False):
self.group_id = group_id
self.clean_group_dir = OPENFACE_OUTPUT_DIR / \
group_id / (group_id + '_clean')
if not Path(self.clean_group_dir).is_dir():
log(
'ERROR',
'This step requires the output of openface data cleaning step')
os.makedirs(self.clean_group_dir, exist_ok=True)
self.output_group_dir = OPENFACE_OUTPUT_DIR / \
group_id / (group_id + '_processed')
os.makedirs(self.output_group_dir, exist_ok=True)
self.experiment = Experiment(group_id)
json.dump(self.experiment.to_json(),
open(self.output_group_dir / (self.group_id + '.json'), 'w'))
self.subjects = dict()
self.is_valid_frame = None
self.prettify = prettify
self.verbose = verbose
def camera_frame_parse_subjects(self, camera, frame_data):
frame_subjects = frame_data['subjects']
frame_subject_pose = frame_subjects['pose']
frame_idx = frame_data['frame']
self.current_frame = frame_idx
for subject_id, subject in self.subjects.items():
if subject_id in frame_subject_pose:
subject_data = frame_subject_pose[subject_id]
subject._update_pose(
camera, subject_data, self.verbose)
elif camera not in subject.previous_pose:
# Subject has no pose nor previous pose.
# Must skip camera frame as it is impossible to reuse keypoints
# from other camera due to lack of 3D alignment. Future Consideration.
if self.verbose:
log('INFO', 'Subject has no previous pose.' +
'(frame: %s, camera: %s, subject: %s)' %
(frame_idx, camera, subject))
return False
else:
if self.verbose:
log('INFO', 'Subject (%s) has no pose in this frame (%s - %s), but previous pose on this camera can be used' %
(subject_id, frame_idx, camera))
if subject.previous_pose[camera]:
subject._update_pose(
camera, subject.previous_pose[camera], self.verbose)
else:
return False
return True
def save_output(self, output_directory, frame_validity):
frame = self.current_frame
output_frame_file = output_directory / \
("frame_%.12d_processed.json" % (frame))
os.makedirs(output_directory, exist_ok=True)
if not output_directory.is_dir():
log('ERROR', 'Directory does not exist')
obj = {
"frame":
self.current_frame,
"is_enhanced_data_valid":
frame_validity,
"group":
self.to_json(),
"subjects": [
subject.to_json()
for subject_id, subject in self.subjects.items()
],
}
if self.prettify:
json.dump(obj, open(output_frame_file, 'w'), indent=2)
else:
json.dump(obj, open(output_frame_file, 'w'))
def __init__(self,
group_id: str,
prettify: bool = False,
verbose: bool = False):
self.group_id = group_id
self.clean_group_dir = OPENPOSE_OUTPUT_DIR / \
group_id / (group_id + '_clean')
if not Path(self.clean_group_dir).is_dir():
log(
'ERROR',
'This step requires the output of openpose data cleaning step')
os.makedirs(self.clean_group_dir, exist_ok=True)
self.output_group_dir = OPENPOSE_OUTPUT_DIR / \
group_id / (group_id + '_processed')
os.makedirs(self.output_group_dir, exist_ok=True)
self.experiment = Experiment(group_id)
json.dump(self.experiment.to_json(),
open(self.output_group_dir / (self.group_id + '.json'), 'w'))
self.current_frame = -1
self.n_subjects = -1
self.subjects = {
subject_id: OpenposeSubject(subject_id, verbose)
for subject_id in range(1, 5)
}
self.intragroup_distance = dict()
self.prettify = prettify
self.verbose = verbose
def process(self, tasks_directories: dict, specific_frame: int = None, display: bool = False):
if specific_frame is not None:
log('WARN', 'Impossible to calculate energy in a single specific frame. Skipping video processing step')
else:
for task in tasks_directories:
output_directory = self.output_group_dir / task.name
os.makedirs(output_directory, exist_ok=True)
if not output_directory.is_dir():
log('ERROR', 'Directory does not exist')
task_video_files = [
x for x in task.iterdir() if x.suffix in VALID_VIDEO_TYPES]
video_caps = {int(re.search(r'(?<=Videopc)(\d{1})(?=\d{12})', x.name).group(
0)): cv2.VideoCapture(str(x)) for x in task_video_files}
thread_list = list()
for cap_cam, video_cap in video_caps.items():
thread = Worker(cap_cam, cap_cam, video_cap, output_directory,
verbose=self.verbose, prettify=self.prettify, display=display)
thread.start()
thread_list.append(thread)
for thread in thread_list:
thread.join()
metrics = dict()
for thread in thread_list:
metrics['energy_htmp'] = thread.cumulative_energy_frame
self.save_output(metrics, task.name, thread.camera)
def n_subjects(self, value):
if value == 4 or value == -1:
self.__n_subjects = value
else:
log(
'ERROR',
'invalid number of subjects. Keep previous frame\'s subject pose'
)
def current_frame(self, value):
if value >= self.current_frame or value <= 0:
self.__current_frame = value
else:
log(
'ERROR',
'Analyzing previous frame. Frame processing should be ordered.'
)
def subjects(self, value):
self.__subjects = value
try:
assert len(value) == 4
self.__subjects = value
self.frame_data_validity = True
except AssertionError:
total = {1, 2, 3, 4}
found = set()
for sub in value:
found.add(sub.quadrant)
if self.verbose:
log("WARN", "Invalid number of subjects. Found %s out of 4 required in frame %s of camera %s. Missing: %s" % (
len(value), self.frame, self.camera, total.difference(found)))
def process_frames(self,
task_frame_df: pd.DataFrame,
output_directory: str,
prettify: bool = False,
verbose: bool = False,
display: bool = False):
"""Process each frame. Filter Skeleton parts detected and parse Subjects
Args:
camera_frame_files (dict): Camera frame files
output_directory (str): Output directory path
prettify (bool, optional): Pretty JSON print. Defaults to False.
verbose (bool, optional): Verbose. Defaults to False.
display (bool, optional): Display visualization. Defaults to False.
"""
frames = list(task_frame_df['frame'].unique())
for frame in frames:
df = task_frame_df.loc[task_frame_df.frame == frame]
df = df.loc[df.success == 1]
frame_cameras_count = df.groupby('camera').size()
for frame_camera in frame_cameras_count.iteritems():
_cam = frame_camera[0]
_cam_count = frame_camera[1]
if verbose:
if _cam_count < self.experiment._n_subjects:
log(
"WARN", "Camera %s only has %s subjects faces" %
(_cam, _cam_count))
output_frame_directory = output_directory / _cam
output_frame_file = output_frame_directory / \
("%s_%.12d_clean.json" % (_cam, frame))
os.makedirs(output_frame_directory, exist_ok=True)
openface_frame = ExperimentCameraFrame(
_cam,
int(frame),
df[['confidence', 'face_id'] +
self.columns_2d_facial_lmks + self.columns_2d_eye_lmks +
self.columns_gaze[6:8]],
OPENFACE_KEY,
verbose=verbose,
display=display)
self.save_data(df,
openface_frame,
output_frame_file,
prettify=prettify)
def main(video_files: list, verbose: bool = False):
group_id = list(filter(None, video_files[0].split('/')))[-1]
experiment = Experiment(group_id)
video_files = [
directory + filename
for filename in filter_files(fetch_files_from_directory([directory]),
valid_types=VALID_VIDEO_TYPES)
]
video_files.sort()
timestamp_files = [
splitext(f)[0][::-1].replace('Video'[::-1], 'Timestamp'[::-1], 1)[::-1]
+ ".txt" for f in video_files
]
if len(video_files) != 3 and len(timestamp_files) != 3:
log(
'ERROR',
'Specify only 3 video files (and corresponding timestamps - Optional: Default is searching for same file name)'
)
exit()
out_dir_base = '%s/%s' % (DATASET_SYNC, str(Path(
video_files[0]).parent).split('/')[-1])
out_dirs = list()
for n in range(experiment._n_tasks):
out_dirs.append('%s/%s_%s/' % (out_dir_base, 'task', n + 1))
if verbose:
print('Saving to: ', out_dirs)
try:
for _dir in out_dirs:
os.makedirs(_dir)
except OSError as e:
if e.errno != errno.EEXIST:
raise
cap_list = list()
for i in range(len(video_files)):
_id = str(i + 1)
vid = CameraVideo(
"VID" + _id, video_files[i], CAM_ROI['pc' + _id],
PERSON_IDENTIFICATION_GRID['pc' + _id], timestamp_files[i],
out_dirs,
splitext(video_files[i])[0].split('/')[-1] + "_sync.avi")
cap_list.append(vid)
if not all(vid.cap.isOpened() for vid in cap_list):
log('ERROR', 'Error opening video stream or file')
exit()
marker_validator = {ord(str(i)): False for i in range(1, 9)}
precision_step = 10
while (all(vid.cap.isOpened() for vid in cap_list)):
alignment, align_by = timestamp_align(cap_list)
to_align_list = cap_list if alignment is True else alignment
for vid in to_align_list:
# Read frame
vid.ret, vid.frame = vid.cap.read()
vid.current_frame_idx += 1
# print(vid.current_frame_idx)
# Update current_timestamp
file_ts = vid.timestamps.readline()
vid.current_timestamp = int(file_ts) if file_ts is not '' else -1
key = cv2.waitKey(25) & 0xff
# TODO: While paused, allow to set markers
if key == 0x20: # Pause Video
while cv2.waitKey(-1) & 0xFF != 0x20: # Resume Video
pass
if key == ord('d'): # Skip
for vid in cap_list:
vid.current_frame_idx += FRAME_SKIP
vid.cap.set(cv2.CAP_PROP_POS_FRAMES, vid.current_frame_idx)
if key == ord('a'): # Jump Back
for vid in cap_list:
vid.current_frame_idx -= FRAME_SKIP
if vid.current_frame_idx < vid.init_synced_frame:
vid.current_frame_idx = vid.init_synced_frame
vid.cap.set(cv2.CAP_PROP_POS_FRAMES, vid.current_frame_idx)
if key == ord('f'): # Jump Back
for vid in cap_list:
vid.current_frame_idx -= FRAME_SKIP * 10
if vid.current_frame_idx < vid.init_synced_frame:
vid.current_frame_idx = vid.init_synced_frame
vid.cap.set(cv2.CAP_PROP_POS_FRAMES, vid.current_frame_idx)
# if key == ord('s'): # Set sync point
# print("SET SYNC POINT")
if key == ord('u'):
vid = cap_list[0]
vid.current_frame_idx -= precision_step
vid.cap.set(cv2.CAP_PROP_POS_FRAMES, vid.current_frame_idx)
if key == ord('i'):
vid = cap_list[0]
vid.current_frame_idx += precision_step
vid.cap.set(cv2.CAP_PROP_POS_FRAMES, vid.current_frame_idx)
if key == ord('j'):
vid = cap_list[1]
vid.current_frame_idx -= precision_step
vid.cap.set(cv2.CAP_PROP_POS_FRAMES, vid.current_frame_idx)
if key == ord('k'):
vid = cap_list[1]
vid.current_frame_idx += precision_step
vid.cap.set(cv2.CAP_PROP_POS_FRAMES, vid.current_frame_idx)
if key == ord('n'):
vid = cap_list[2]
vid.current_frame_idx -= precision_step
vid.cap.set(cv2.CAP_PROP_POS_FRAMES, vid.current_frame_idx)
if key == ord('m'):
vid = cap_list[2]
vid.current_frame_idx += precision_step
vid.cap.set(cv2.CAP_PROP_POS_FRAMES, vid.current_frame_idx)
if key >= ord('1') and key <= ord('8'):
print("Marker %s set" % chr(key))
marker_validator[key] = True
for vid in cap_list:
vid.markers[key] = vid.current_frame_idx
if key == ord('t'):
print("Task Separator set")
for vid in cap_list:
vid.task_separator = vid.current_frame_idx
if all([vid.ret for vid in cap_list]):
if alignment == True and align_by is not None: # Videos are in sync
for vid in cap_list:
if vid.init_synced_frame == 0:
vid.init_synced_frame = vid.current_frame_idx
roi = vid.roi
grid = vid.grid
grid_horitonzal_axis = grid['horizontal']
grid_vertical_axis = grid['vertical']
cv2.rectangle(vid.frame, (roi['xmin'], roi['ymin']),
(roi['xmax'], roi['ymax']), (0, 255, 0), 2)
cv2.line(vid.frame, (grid_horitonzal_axis['x0'],
grid_horitonzal_axis['y']),
(grid_horitonzal_axis['x1'],
grid_horitonzal_axis['y']), (0, 0, 255), 1)
cv2.line(
vid.frame,
(grid_vertical_axis['x'], grid_vertical_axis['y0']),
(grid_vertical_axis['x'], grid_vertical_axis['y1']),
(0, 0, 255), 1)
cv2.imshow(vid.title, vid.frame)
if key == ord('g'): # Save
if verbose:
print("Start writting phase")
for vid in cap_list:
valid_markers = [
marker for marker in marker_validator.items()
if marker[1] == True
]
if len(valid_markers) % 2 != 0:
log(
'ERROR',
'Odd number of markers. Number of markers should be an even number.'
)
break
first_experience_markers = list(vid.markers.keys())[:2]
second_experience_markers = list(vid.markers.keys())[2:4]
third_experience_markers = list(vid.markers.keys())[4:6]
fourth_experience_markers = list(vid.markers.keys())[6:8]
for i in range(0, (len(vid.markers.keys()) + 1) - 1, 2):
task_markers = list(vid.markers.keys())[i:i + 2]
if verbose:
print("Vid %s Saving Task" % (vid.title))
cut_from_until(vid, vid.markers[task_markers[0]],
vid.markers[task_markers[1]])
break
if key == ord('q'):
break
else:
break
for vid in cap_list:
vid.cap.release()
vid.writer_task1.release()
vid.writer_task2.release()
cv2.destroyAllWindows()
def aggregate(self, prettify: bool = False):
"""Aggregate framework clean output data
Follow openpose frame list as openpose always outputs a file per frame
Args:
prettify (bool, optional): Pretty JSON print. Defaults to False.
"""
openpose_data = self.openpose_data
densepose_data = self.densepose_data
openface_data = self.openface_data
video_data = self.video_data
if not openpose_data:
log('ERROR', 'Nothing to Aggregate. Use -op -of and -dp to include openpose, openface and densepose data. The use of Openpose data is mandatory.')
if openface_data:
cleaned_openface = openface_data['cleaned']
processed_openface = openface_data['processed']
if densepose_data:
cleaned_densepose = densepose_data['cleaned']
processed_densepose = densepose_data['processed']
cleaned_openpose = openpose_data['cleaned']
processed_openpose = openpose_data['processed']
tasks = cleaned_openpose.keys()
if self.specific_task is not None:
tasks = [task for task in tasks if str(self.specific_task) in task]
for task in tasks:
self.reset_files = True
output_frame_directory = self.group_directory / \
FEATURE_AGGREGATE_DIR / task
makedirs(output_frame_directory, exist_ok=True)
processed_openpose_files = processed_openpose[task]
if self.specific_frame is not None:
processed_openpose_files = {
self.specific_frame: processed_openpose_files[self.specific_frame]}
for frame_idx in processed_openpose_files:
output_frame_file = output_frame_directory / \
("%.12d" % frame_idx + '.json')
aggregate_frame = AggregateFrame(frame_idx)
# OPENPOSE
if self.verbose:
print("Cleaned OpenPose")
self.framework_being_processed = OPENPOSE_KEY
for camera in cleaned_openpose[task]:
cleaned_openpose_files = cleaned_openpose[task][camera]
openpose_clean_frame_data = json.load(
open(cleaned_openpose_files[frame_idx], 'r'))
aggregate_frame = self.read_frame_data(aggregate_frame,
openpose_clean_frame_data,
camera=camera,
frame_data_type='raw')
if self.verbose:
print("Processed Openpose")
openpose_processed_frame_data = json.load(
open(processed_openpose_files[frame_idx], 'r'))
aggregate_frame = self.read_frame_data(aggregate_frame,
openpose_processed_frame_data,
frame_data_type='processed')
# OPENFACE
if openface_data:
if self.verbose:
print("Cleaned OpenFace")
self.framework_being_processed = OPENFACE_KEY
cleaned_task_openface = cleaned_openface[task]
for camera in cleaned_task_openface:
cleaned_openface_files = cleaned_task_openface[camera]
if frame_idx in cleaned_openface_files:
openface_clean_frame_data = json.load(
open(cleaned_openface_files[frame_idx], 'r'))
aggregate_frame = self.read_frame_data(aggregate_frame,
openface_clean_frame_data,
camera=camera,
frame_data_type='raw')
if self.verbose:
print("Processed Openface")
processed_task_openface = processed_openface[task]
if frame_idx in processed_task_openface:
processed_task_frame = processed_task_openface[frame_idx]
for camera, frame_file in processed_task_frame.items():
openface_processed_frame_data = json.load(
open(frame_file, 'r'))
aggregate_frame = self.read_frame_data(aggregate_frame,
openface_processed_frame_data,
camera=camera,
frame_data_type='processed')
# DENSEPOSE
if densepose_data:
if self.verbose:
print("Cleaned Densepose")
self.framework_being_processed = DENSEPOSE_KEY
for camera in cleaned_densepose[task]:
cleaned_densepose_files = cleaned_densepose[task][camera]
densepose_clean_frame_data = json.load(
open(cleaned_densepose_files[frame_idx], 'r'))
aggregate_frame = self.read_frame_data(aggregate_frame,
densepose_clean_frame_data,
camera=camera,
frame_data_type='raw')
if self.verbose:
print("Processed Densepose")
densepose_processed_frame_data = json.load(
open(processed_densepose[task][frame_idx], 'r'))
aggregate_frame = self.read_frame_data(aggregate_frame,
densepose_processed_frame_data,
frame_data_type='processed')
# VIDEO
if video_data:
self.framework_being_processed = OPENCV_KEY
processed_video_data = video_data['processed']
if task in processed_video_data:
processed_video_data_task = processed_video_data[task]
if frame_idx in processed_video_data_task:
processed_video_data_frame = processed_video_data_task[frame_idx]
for camera, frame_file in processed_video_data_frame.items():
video_data_processed_frame_data = json.load(
open(frame_file, 'r'))
aggregate_frame = self.read_frame_data(aggregate_frame,
video_data_processed_frame_data,
camera=camera,
frame_data_type='processed')
self.plot_generator(aggregate_frame, output_frame_directory)
if prettify:
json.dump(aggregate_frame.to_json(), open(
output_frame_file, 'w'), indent=2)
else:
json.dump(aggregate_frame.to_json(),
open(output_frame_file, 'w'))
if video_data:
video_data_heatmaps = video_data['heatmap']
if task in video_data_heatmaps:
video_data_heatmaps_task = video_data_heatmaps[task]
for file_name in video_data_heatmaps_task:
shutil.copy(file_name, output_frame_directory)
def read_frame_data(self, agg_frame: AggregateFrame, frame_data: dict, camera: str = None, frame_data_type: str = None):
agg_frame_subjects = agg_frame.subjects
if 'is_raw_data_valid' in frame_data:
if agg_frame.is_raw_data_valid is not False:
agg_frame.is_raw_data_valid = frame_data['is_raw_data_valid']
frame_data_type = 'raw'
if agg_frame.is_processed_data_valid is None and 'is_enhanced_data_valid' in frame_data:
agg_frame.is_processed_data_valid = frame_data['is_enhanced_data_valid']
frame_data_type = 'processed'
if 'group' in frame_data:
updated_value = frame_data['group']
framework_being_processed = self.framework_being_processed.lower()
if camera:
if framework_being_processed not in agg_frame.group:
agg_frame.group[framework_being_processed] = dict()
for key, value in updated_value.items():
if key not in agg_frame.group[framework_being_processed]:
agg_frame.group[framework_being_processed][key] = dict()
agg_frame.group[framework_being_processed][key].update({
camera: value
})
else:
agg_frame.group.update({
framework_being_processed: updated_value
})
if 'subjects' in frame_data:
frame_subjects = frame_data['subjects']
for subject in frame_subjects:
# ID
if 'id' not in subject:
log('ERROR', 'Invalid Subject. Cannot parse subject ID.')
subject_id = subject['id']
agg_subject = agg_frame_subjects[subject_id] if subject_id in agg_frame_subjects \
else AggregateSubject(subject_id)
# FACE
if 'face' in subject:
subject_face_data = subject['face']
if frame_data_type == 'raw':
agg_subject.clean_face_data, _ = self.parse_data(
agg_subject.clean_face_data, subject_face_data, camera=camera)
if frame_data_type == 'processed':
processed_face_data, processed_face_metrics = self.parse_data(
agg_subject.processed_face_data, subject_face_data, camera=camera)
agg_subject.processed_face_data = processed_face_data
if processed_face_metrics:
agg_subject.metrics.update(processed_face_metrics)
# POSE
if 'pose' in subject:
subject_pose_data = subject['pose']
if frame_data_type == 'raw':
agg_subject.clean_pose_data, _ = self.parse_data(
agg_subject.clean_pose_data, subject_pose_data, camera)
if frame_data_type == 'processed':
processed_pose_data, processed_pose_metrics = self.parse_data(
agg_subject.processed_pose_data, subject_pose_data)
agg_subject.processed_pose_data = processed_pose_data
if processed_pose_metrics:
agg_subject.metrics.update(processed_pose_metrics)
agg_frame.subjects[subject_id] = agg_subject
return agg_frame
def handle_frames(self,
camera_frame_files: dict,
output_directory: str,
display: bool = False):
for frame_idx in sorted(camera_frame_files):
# print('=== FRAME %s ===' % frame_idx)
self.current_frame = frame_idx
frame_camera_dict = camera_frame_files[frame_idx]
for camera, frame_file in frame_camera_dict.items():
output_path_dir = output_directory / camera
output_path = output_path_dir / \
("%s_%.12d_processed.json" % (camera, frame_idx))
os.makedirs(output_path_dir, exist_ok=True)
data = json.load(open(frame_file))
# TODO: Replace by condition if needed
self.is_valid_frame = data['is_raw_data_valid']
frame_subjects = dict()
for subject in data['subjects']:
subject_id = subject['id']
# print("== SUBJECT %s ==" % subject_id)
if subject_id in self.subjects:
openface_subject = self.subjects[subject_id]
else:
openface_subject = OpenfaceSubject(subject['id'])
self.subjects[subject_id] = openface_subject
# Parse data
subject_openface_data = subject['face']['openface']
# EMOTION IDENTIFICATION
openface_subject.face = subject_openface_data
openface_subject.emotion = self.identify_emotion(
subject_openface_data['AUs'])
# HEAD MOVEMENT DIRECTION
head_rotation_data = subject_openface_data['head']
if len(openface_subject.data_buffer['head']
) >= FRAME_THRESHOLD:
openface_subject.data_buffer['head'].pop(0)
openface_subject.data_buffer['head'].append(
head_rotation_data)
if len(openface_subject.data_buffer['head']
) == FRAME_THRESHOLD:
openface_subject.head_rotation = self.identify_head_movement(
openface_subject.data_buffer['head'])
# EYE MOVEMENT DIRECTION
eye_gaze_data = subject_openface_data['gaze']
if len(openface_subject.data_buffer['eye']
) >= FRAME_THRESHOLD:
openface_subject.data_buffer['eye'].pop(0)
openface_subject.data_buffer['eye'].append(eye_gaze_data)
if len(openface_subject.data_buffer['eye']
) == FRAME_THRESHOLD:
openface_subject.eye_gaze = self.identify_eye_gaze_movement(
openface_subject.data_buffer['eye'])
# Update subject - Not needed?
frame_subjects[subject_id] = openface_subject
write = self.save_output(output_path, frame_subjects)
if not write:
log('ERROR',
'Could not save frame %s to %s' % (frame_idx, output_path))