blakeblackshear.frigate/frigate/motion/improved_motion.py
Blake Blackshear d81dd60fef
Improve motion detection and region selection (#6741)
* refactor existing motion detector

* implement and use cnt bgsub

* pass fps to motion detector

* create a simplified motion detector

* lightning detection

* update default motion config

* lint imports

* use estimated boxes for regions

* use improved motion detector

* update test

* use a different strategy for clustering motion and object boxes

* increase alpha during calibration

* simplify object consolidation

* add some reasonable constraints to the estimated box

* adjust cluster boundary to 10%

* refactor

* add disabled debug code

* fix variable scope
2023-06-11 08:45:11 -05:00

144 lines
5.0 KiB
Python

import cv2
import imutils
import numpy as np
from frigate.config import MotionConfig
from frigate.motion import MotionDetector
class ImprovedMotionDetector(MotionDetector):
def __init__(
self,
frame_shape,
config: MotionConfig,
fps: int,
improve_contrast,
threshold,
contour_area,
):
self.config = config
self.frame_shape = frame_shape
self.resize_factor = frame_shape[0] / config.frame_height
self.motion_frame_size = (
config.frame_height,
config.frame_height * frame_shape[1] // frame_shape[0],
)
self.avg_frame = np.zeros(self.motion_frame_size, np.float32)
self.avg_delta = np.zeros(self.motion_frame_size, np.float32)
self.motion_frame_count = 0
self.frame_counter = 0
resized_mask = cv2.resize(
config.mask,
dsize=(self.motion_frame_size[1], self.motion_frame_size[0]),
interpolation=cv2.INTER_LINEAR,
)
self.mask = np.where(resized_mask == [0])
self.save_images = False
self.calibrating = True
self.improve_contrast = improve_contrast
self.threshold = threshold
self.contour_area = contour_area
def detect(self, frame):
motion_boxes = []
gray = frame[0 : self.frame_shape[0], 0 : self.frame_shape[1]]
# resize frame
resized_frame = cv2.resize(
gray,
dsize=(self.motion_frame_size[1], self.motion_frame_size[0]),
interpolation=cv2.INTER_LINEAR,
)
resized_frame = cv2.GaussianBlur(resized_frame, (3, 3), cv2.BORDER_DEFAULT)
# Improve contrast
if self.improve_contrast.value:
resized_frame = cv2.equalizeHist(resized_frame)
# mask frame
resized_frame[self.mask] = [255]
if self.save_images or self.calibrating:
self.frame_counter += 1
# compare to average
frameDelta = cv2.absdiff(resized_frame, cv2.convertScaleAbs(self.avg_frame))
# compute the threshold image for the current frame
thresh = cv2.threshold(
frameDelta, self.threshold.value, 255, cv2.THRESH_BINARY
)[1]
# dilate the thresholded image to fill in holes, then find contours
# on thresholded image
thresh_dilated = cv2.dilate(thresh, None, iterations=1)
cnts = cv2.findContours(
thresh_dilated, cv2.RETR_EXTERNAL, cv2.CHAIN_APPROX_SIMPLE
)
cnts = imutils.grab_contours(cnts)
# loop over the contours
total_contour_area = 0
for c in cnts:
# if the contour is big enough, count it as motion
contour_area = cv2.contourArea(c)
total_contour_area += contour_area
if contour_area > self.contour_area.value:
x, y, w, h = cv2.boundingRect(c)
motion_boxes.append(
(
int(x * self.resize_factor),
int(y * self.resize_factor),
int((x + w) * self.resize_factor),
int((y + h) * self.resize_factor),
)
)
pct_motion = total_contour_area / (
self.motion_frame_size[0] * self.motion_frame_size[1]
)
# once the motion drops to less than 1% for the first time, assume its calibrated
if pct_motion < 0.01:
self.calibrating = False
# if calibrating or the motion contours are > 80% of the image area (lightning, ir, ptz) recalibrate
if self.calibrating or pct_motion > self.config.lightning_threshold:
motion_boxes = []
self.calibrating = True
if self.save_images:
thresh_dilated = cv2.cvtColor(thresh_dilated, cv2.COLOR_GRAY2BGR)
for b in motion_boxes:
cv2.rectangle(
thresh_dilated,
(int(b[0] / self.resize_factor), int(b[1] / self.resize_factor)),
(int(b[2] / self.resize_factor), int(b[3] / self.resize_factor)),
(0, 0, 255),
2,
)
cv2.imwrite(
f"debug/frames/improved-{self.frame_counter}.jpg", thresh_dilated
)
if len(motion_boxes) > 0:
self.motion_frame_count += 1
if self.motion_frame_count >= 10:
# only average in the current frame if the difference persists for a bit
cv2.accumulateWeighted(
resized_frame,
self.avg_frame,
0.2 if self.calibrating else self.config.frame_alpha,
)
else:
# when no motion, just keep averaging the frames together
cv2.accumulateWeighted(
resized_frame,
self.avg_frame,
0.2 if self.calibrating else self.config.frame_alpha,
)
self.motion_frame_count = 0
return motion_boxes