add ability to process every nth frame

This commit is contained in:
blakeblackshear 2019-07-01 21:17:44 -05:00 committed by Blake Blackshear
parent 834a3df0bc
commit 59a4b0e650

View File

@ -13,7 +13,7 @@ from . objects import ObjectCleaner, BestPersonFrame
from . mqtt import MqttObjectPublisher
# fetch the frames as fast a possible and store current frame in a shared memory array
def fetch_frames(shared_arr, shared_frame_time, frame_lock, frame_ready, frame_shape, rtsp_url):
def fetch_frames(shared_arr, shared_frame_time, frame_lock, frame_ready, frame_shape, rtsp_url, take_frame=1):
# convert shared memory array into numpy and shape into image array
arr = tonumpyarray(shared_arr).reshape(frame_shape)
frame_size = frame_shape[0] * frame_shape[1] * frame_shape[2]
@ -35,8 +35,12 @@ def fetch_frames(shared_arr, shared_frame_time, frame_lock, frame_ready, frame_s
pipe = sp.Popen(ffmpeg_cmd, stdout = sp.PIPE, bufsize=frame_size)
frame_num = 0
while True:
raw_image = pipe.stdout.read(frame_size)
frame_num += 1
if (frame_num % take_frame) != 0:
continue
frame = (
np
.frombuffer(raw_image, np.uint8)
@ -125,6 +129,7 @@ class Camera:
self.detected_objects = []
self.recent_frames = {}
self.rtsp_url = get_rtsp_url(self.config['rtsp'])
self.take_frame = self.config.get('take_frame', 1)
self.regions = self.config['regions']
self.frame_shape = get_frame_shape(self.rtsp_url)
self.mqtt_client = mqtt_client
@ -205,7 +210,8 @@ class Camera:
# create the process to capture frames from the RTSP stream and store in a shared array
print("Creating a new capture process...")
self.capture_process = mp.Process(target=fetch_frames, args=(self.shared_frame_array,
self.shared_frame_time, self.frame_lock, self.frame_ready, self.frame_shape, self.rtsp_url))
self.shared_frame_time, self.frame_lock, self.frame_ready, self.frame_shape,
self.rtsp_url, self.take_frame))
self.capture_process.daemon = True
print("Starting a new capture process...")
self.capture_process.start()