def _launch_folder(self):
""" Launch :class:`lib.multithreading.MultiThread` to retrieve faces from a
folder of images.
Goes through the file list one at a time, passing each file to a separate background
thread for some speed up.
"""
reader = SingleFrameLoader(self._location)
num_threads = min(reader.count, self._num_threads)
frame_split = reader.count // self._num_threads
logger.debug("total images: %s, num_threads: %s, frames_per_thread: %s",
reader.count, num_threads, frame_split)
for idx in range(num_threads):
is_final = idx == num_threads - 1
start_idx = idx * frame_split
end_idx = reader.count if is_final else start_idx + frame_split
thread = MultiThread(self._load_from_folder, reader, start_idx, end_idx)
thread.start()
self._threads.append(thread)
def _load_images(self, frames_location, video_meta_data):
""" Load the images in a background thread. """
self._loader = SingleFrameLoader(frames_location,
video_meta_data=video_meta_data)
self._globals.set_frame_count(self._loader.count)
class FrameLoader():
""" Loads the frames, sets the frame count to :attr:`TkGlobals.frame_count` and handles the
return of the correct frame for the GUI.
Parameters
----------
tk_globals: :class:`~tools.manual.manual.TkGlobals`
The tkinter variables that apply to the whole of the GUI
frames_location: str
The path to the input frames
video_meta_data: dict
The meta data held within the alignments file, if it exists and the input is a video
"""
def __init__(self, tk_globals, frames_location, video_meta_data):
logger.debug(
"Initializing %s: (tk_globals: %s, frames_location: '%s', "
"video_meta_data: %s)", self.__class__.__name__, tk_globals,
frames_location, video_meta_data)
self._globals = tk_globals
self._loader = None
self._current_idx = 0
self._init_thread = self._background_init_frames(
frames_location, video_meta_data)
self._globals.tk_frame_index.trace("w", self._set_frame)
logger.debug("Initialized %s", self.__class__.__name__)
@property
def is_initialized(self):
""" bool: ``True`` if the Frame Loader has completed initialization otherwise
``False``. """
thread_is_alive = self._init_thread.is_alive()
if thread_is_alive:
self._init_thread.check_and_raise_error()
else:
self._init_thread.join()
# Setting the initial frame cannot be done in the thread, so set when queried from main
self._set_frame(initialize=True)
return not thread_is_alive
@property
def video_meta_data(self):
""" dict: The pts_time and key frames for the loader. """
return self._loader.video_meta_data
def _background_init_frames(self, frames_location, video_meta_data):
""" Launch the images loader in a background thread so we can run other tasks whilst
waiting for initialization. """
thread = MultiThread(self._load_images,
frames_location,
video_meta_data,
thread_count=1,
name="{}.init_frames".format(
self.__class__.__name__))
thread.start()
return thread
def _load_images(self, frames_location, video_meta_data):
""" Load the images in a background thread. """
self._loader = SingleFrameLoader(frames_location,
video_meta_data=video_meta_data)
self._globals.set_frame_count(self._loader.count)
def _set_frame(self, *args, initialize=False): # pylint:disable=unused-argument
""" Set the currently loaded frame to :attr:`_current_frame` and trigger a full GUI update.
If the loader has not been initialized, or the navigation position is the same as the
current position and the face is not zoomed in, then this returns having done nothing.
Parameters
----------
args: tuple
:class:`tkinter.Event` arguments. Required but not used.
initialize: bool, optional
``True`` if initializing for the first frame to be displayed otherwise ``False``.
Default: ``False``
"""
position = self._globals.frame_index
if not initialize and (position == self._current_idx
and not self._globals.is_zoomed):
logger.trace(
"Update criteria not met. Not updating: (initialize: %s, position: %s, "
"current_idx: %s, is_zoomed: %s)", initialize, position,
self._current_idx, self._globals.is_zoomed)
return
if position == -1:
filename = "No Frame"
frame = np.ones(self._globals.frame_display_dims + (3, ),
dtype="uint8")
else:
filename, frame = self._loader.image_from_index(position)
logger.trace("filename: %s, frame: %s, position: %s", filename,
frame.shape, position)
self._globals.set_current_frame(frame, filename)
self._current_idx = position
self._globals.tk_update.set(True)
self._globals.tk_update_active_viewport.set(True)