def get_processed_frame_object(frame_obj, scale=1.0):
"""Processes value produced by producer, returns prediction with png image.
:param frame_obj: frame dictionary with frame information and frame itself
:param scale: (0, 1] scale image before face recognition, speeds up processing, decreases accuracy
:return: A dict updated with faces found in that frame, i.e. their location and encoding.
"""
frame = np_from_json(frame_obj,
prefix_name=ORIGINAL_PREFIX) # frame_obj = json
# Convert the image from BGR color (which OpenCV uses) to RGB color (which face_recognition uses)
frame = cv2.cvtColor(frame.astype(np.uint8), cv2.COLOR_BGR2RGB)
if scale != 1:
# Resize frame of video to scale size for faster face recognition processing
rgb_small_frame = cv2.resize(frame, (0, 0), fx=scale, fy=scale)
else:
rgb_small_frame = frame
with timer("PROCESS RAW FRAME {}".format(frame_obj["frame_num"])):
# Find all the faces and face encodings in the current frame of video
with timer("Locations in frame"):
face_locations = np.array(
face_recognition.face_locations(rgb_small_frame))
face_locations_dict = np_to_json(face_locations,
prefix_name="face_locations")
with timer("Encodings in frame"):
face_encodings = np.array(
face_recognition.face_encodings(rgb_small_frame,
face_locations))
face_encodings_dict = np_to_json(face_encodings,
prefix_name="face_encodings")
frame_obj.update(face_locations_dict)
frame_obj.update(face_encodings_dict)
return frame_obj
def get_face_object(frame_obj, query_faces_data, scale=1.0):
"""Match query faces with detected faces in the frame, if matched put box and a tag.
:param frame_obj: frame dictionary with frame information, frame, face encodings, locations.
:param query_faces_data: message from query face topic, contains encoding and names of faces.
Other way was to broadcast raw image and calculate encodings here.
:param scale: to scale up as 1/scale, if in pre processing frames were scaled down for speedup.
:return: A dict with modified frame, i.e. bounded box drawn around detected persons face.
"""
# get frame from message
frame = np_from_json(frame_obj,
prefix_name=ORIGINAL_PREFIX) # frame_obj = json
# get processed info from message
face_locations = np_from_json(frame_obj, prefix_name="face_locations")
face_encodings = np_from_json(frame_obj, prefix_name="face_encodings")
# Convert the image from BGR color (which OpenCV uses) to RGB color (which face_recognition uses)
frame = cv2.cvtColor(frame.astype(np.uint8), cv2.COLOR_BGR2RGB)
# get info entered by user through UI
known_face_encodings = np_from_json(
query_faces_data,
prefix_name="known_face_encodings").tolist() # (n, 128)
known_faces = np_from_json(query_faces_data,
prefix_name="known_faces").tolist() # (n, )
with timer("\nFACE RECOGNITION {}\n".format(frame_obj["frame_num"])):
# Faces found in this image
face_names = []
with timer("Total Match time"):
for i, face_encoding in enumerate(face_encodings):
# See if the face is a match for the known face(s)
with timer("Match {}th face time".format(i)):
matches = face_recognition.compare_faces(
known_face_encodings, face_encoding)
name = "Unknown"
# If a match was found in known_face_encodings, just use the first one.
if True in matches:
first_match_index = matches.index(True)
name = known_faces[first_match_index]
face_names.append(name.title())
# Mark the results for this frame
for (top, right, bottom,
left), name in zip(face_locations, face_names):
# Scale back up face locations since the frame we detected in was scaled to 1/4 size
if scale != 1:
top *= int(1 / scale)
right *= int(1 / scale)
bottom *= int(1 / scale)
left *= int(1 / scale)
if name == "Unknown":
color = (0, 0, 255) # blue
else:
color = (255, 0, 0) # red
# Draw a box around the face
cv2.rectangle(frame, (left, top), (right, bottom), color, 2)
# Draw a label with a name below the face
cv2.rectangle(frame, (left, bottom - 21), (right, bottom),
color, cv2.FILLED)
cv2.putText(frame, name, (left + 6, bottom - 6),
cv2.FONT_HERSHEY_SIMPLEX, 0.6, (255, 255, 255), 1)
frame = cv2.cvtColor(frame.astype(np.uint8), cv2.COLOR_BGR2RGB)
frame_dict = np_to_json(frame, prefix_name=PREDICTED_PREFIX)
prediction = None
if face_names:
prediction = face_names[0]
result = {
"prediction": prediction,
"predict_time": str(time.time()),
"latency": str(time.time() - int(frame_obj["timestamp"]))
}
frame_obj.update(frame_dict) # update frame with prediction
result.update(frame_obj) # add prediction results
return result