Files
opencv_python_tests/background_heatmap.py
2019-12-06 11:49:04 +01:00

97 lines
3.2 KiB
Python

import numpy as np
import cv2
import time
from typing import List, Iterable
from video_loader import VideoLoader
import numpy
from data.library import ArkiteData
from cv2util import to_8_bit_image
class BackgroundHeatmap:
def __init__(self, frames, append_blur=True, learning_rate=0.0003):
self.append_blur = append_blur
self.frames = frames
self.max_history_len = 2
self.lastframes = []
self.learning_rate = learning_rate
self.heatmap = np.array([])
self.backsub = cv2.createBackgroundSubtractorMOG2()
self.teach_background()
self.reset_sum()
@staticmethod
def to_grayscale(frame):
return cv2.cvtColor(frame, cv2.COLOR_BGR2GRAY)
@staticmethod
def to_floats(frame):
return cv2.normalize(frame, None, alpha=0, beta=1, norm_type=cv2.NORM_MINMAX, dtype=cv2.CV_32F)
@staticmethod
def float_to_gray(frame):
return cv2.normalize(frame, None, alpha=0, beta=255, norm_type=cv2.NORM_MINMAX, dtype=cv2.CV_8UC1)
@staticmethod
def gray_to_heat(frame):
return cv2.applyColorMap(frame, cv2.COLORMAP_JET)
def update_heatmap(self):
self.heatmap = self.gray_to_heat(
self.float_to_gray(
self.to_floats(self.lastsum)
)
)
def update(self, frame):
if self.append_blur:
frame = cv2.blur(frame,(5,5))
self.add_frame_history(self.backsub.apply(frame, None, self.learning_rate))
self.lastsum += self.to_floats(self.lastframe)
self.update_heatmap()
def teach_background(self, frames=None):
if frames is None:
frames = self.frames
for frame in frames:
if self.append_blur:
frame = cv2.blur(frame,(5,5))
# TODO: is it logical here to use the same learning rate?
self.add_frame_history(self.backsub.apply(frame, None, self.learning_rate))
def add_frame_history(self, frame):
if len(self.lastframes) == self.max_history_len:
self.lastframes.pop(0)
self.lastframes.append(frame)
def reset_sum(self):
self.lastsum = self.to_floats(self.lastframe)
def reset(self):
self.reset_sum()
self.update_heatmap()
@property
def lastframe(self):
return self.lastframes[-1]
@property
def bgf_diff(self):
# make binary map
first = cv2.threshold(self.lastframes[1], 60, 255, cv2.THRESH_BINARY)[1]
second = cv2.threshold(self.lastframes[0], 60, 255, cv2.THRESH_BINARY)[1]
return cv2.subtract(first, second)
class BackgroundHeatmapFromGroup(BackgroundHeatmap):
def __init__(self, group, append_blur=True, learning_rate=0.0003):
self.group = group
assert len(self.group[1]) is not 0
# Init with first recording
frames = VideoLoader.extract_frames(self.group[1][0])
super().__init__(frames, append_blur=append_blur, learning_rate=learning_rate)
self.teachRestOfVideosInGroup()
def teachRestOfVideosInGroup(self):
# Slice away first recording since it was passed to super constructor already
for recording in self.group[1][1:]:
frames = VideoLoader.extract_frames(recording)
self.teach_background(frames=frames)