プログラムはwhileループからのリストに書き込まれませんか？

Question

ピクセル強度の差があらかじめ定義されたしきい値より高い場合は、VideoFlagリストに値を書き込もうとしています。しかし出力では、私の出力 'flag.txt'ファイルは空であり、私はなぜそれがわかりません。誰かが私のコードが間違っていることをどのように知っていますか？

ありがとうございます！

import cv2 
import tkinter as tk 
from tkinter.filedialog import askopenfilename 
import numpy as np 
import os 
import matplotlib.pyplot as plt 

MIList =[] 
VideoFlag=[] 

def frame_diff(prev_frame, cur_frame, next_frame): 
    diff_frames1 = cv2.absdiff(next_frame, cur_frame) 

    diff_frames2 = cv2.absdiff(cur_frame, prev_frame) 

    return cv2.bitwise_and(diff_frames1, diff_frames2) 

def get_frame(cap): 
    ret, frame = cap.read() 
    if ret == True: 
     scaling_factor = 1 
     frame = cv2.resize(frame, None, fx = scaling_factor, fy = scaling_factor, interpolation = cv2.INTER_AREA) 
     return cv2.cvtColor(frame, cv2.COLOR_RGB2GRAY) 

def moving_average(MIList, n=30) : 
    ret = np.cumsum(MIList, dtype=float) 
    ret[n:] = ret[n:] - ret[:-n] 
    return ret[n - 1:]/n 

def main(): 

    root = tk.Tk() 
    root.withdraw() 

    selectedvideo = askopenfilename() 
    cap = cv2.VideoCapture(selectedvideo) 
    length = cap.get(cv2.CAP_PROP_FRAME_COUNT) 
    intlength = int(cap.get(cv2.CAP_PROP_FRAME_COUNT)) 
    currentframenumber = cap.get(cv2.CAP_PROP_POS_FRAMES) 
    intcurrentframenumber = int(cap.get(cv2.CAP_PROP_POS_FRAMES)) 
    scaling_factor = 1 
    fourcc = cv2.VideoWriter_fourcc(*'XVID') 
    out = cv2.VideoWriter((selectedvideo + 'motionindexed.avi'),fourcc, 60.0, (640,478), isColor=False) 
    with open((selectedvideo + 'threshold' + '.txt'), 'r') as readthreshold: 
     threshold = float(readthreshold.readline()) 

    prev_frame = get_frame(cap) 
    cur_frame = get_frame(cap) 
    next_frame = get_frame(cap) 

    while (cap.isOpened()): 

     try: 
      cv2.imshow("Object Movement", frame_diff(prev_frame, cur_frame, next_frame)) 
      prev_frame = cur_frame 
      cur_frame = next_frame 
      next_frame = get_frame(cap) 
      differencesquared = (next_frame-cur_frame)**2 
      interframedifference = np.sum(differencesquared) 
      MIList.append(interframedifference) 
      print(interframedifference) 
      if interframedifference >= threshold: 
       out.write(cur_frame) 
       VideoFlag.append(str(intcurrentframenumber + '|' + 1)) 
       print(VideoFlag) 
      elif interframedifference < threshold: 
       VideoFlag.append(str(intcurrentframenumber + '|' + 0)) 
       print(VideoFlag) 

      key = cv2.waitKey(1) 
      if key == ord('q'): 
       break 
     except: 
      break 

    with open((selectedvideo + 'flag' + '.txt'), 'w') as f: 
     for item in VideoFlag: 
      f.write(str(item)) 


    cap.release() 
    cv2.destroyAllWindows() 

if __name__ == '__main__': 
    # this is called if this code was not imported ... ie it was directly run 
    # if this is called, that means there is no GUI already running, so we need to create a root 
    root = tk.Tk() 
    root.withdraw() 
    main() 

Answer 1

# Note that you need to append('a') data to the file instead of writing('w') to it for each iteration. 
# The last line will be empty string and that is what contains finally. 
with open((selectedvideo + 'flag' + '.txt'), 'a') as f: 
    for item in VideoFlag: 
     f.write(str(item)) 

と

with open((selectedvideo + 'flag' + '.txt'), 'w') as f: 
    for item in VideoFlag: 
     f.write(str(item)) 

を交換しても問題が解決しなければなりません。

Answer 2

私は自分の問題を解決したと思っています。何らかの理由で、私の追加メソッドの型が原因で実行されていなかったのですが、私の整数の1つを文字列に変換するのを忘れてしまいました。それを再加工し、私はそれが私の問題を解決したと思う！入力仲間のための乾杯！

import cv2 
import tkinter as tk 
from tkinter.filedialog import askopenfilename 
import numpy as np 
import os 
import matplotlib.pyplot as plt 

def frame_diff(prev_frame, cur_frame, next_frame): 
    diff_frames1 = cv2.absdiff(next_frame, cur_frame) 

    diff_frames2 = cv2.absdiff(cur_frame, prev_frame) 

    return cv2.bitwise_and(diff_frames1, diff_frames2) 

def get_frame(cap): 
    ret, frame = cap.read() 
    if ret == True: 
     scaling_factor = 1 
     frame = cv2.resize(frame, None, fx = scaling_factor, fy = scaling_factor, interpolation = cv2.INTER_AREA) 
     return cv2.cvtColor(frame, cv2.COLOR_RGB2GRAY) 

def main(): 

    root = tk.Tk() 
    root.withdraw() 

    MIList = [] 
    VideoFlag = [] 
    selectedvideo = askopenfilename() 
    cap = cv2.VideoCapture(selectedvideo) 
    length = cap.get(cv2.CAP_PROP_FRAME_COUNT) 
    intlength = int(cap.get(cv2.CAP_PROP_FRAME_COUNT)) 
    currentframenumber = cap.get(cv2.CAP_PROP_POS_FRAMES) 
    intcurrentframenumber = int(cap.get(cv2.CAP_PROP_POS_FRAMES)) 
    scaling_factor = 1 
    fourcc = cv2.VideoWriter_fourcc(*'XVID') 
    out = cv2.VideoWriter((selectedvideo + 'motionindexed.avi'),fourcc, 60.0, (640,478), isColor=False) 
    with open((selectedvideo + 'threshold' + '.txt'), 'r') as readthreshold: 
     threshold = float(readthreshold.readline()) 

    prev_frame = get_frame(cap) 
    cur_frame = get_frame(cap) 
    next_frame = get_frame(cap) 

    while (cap.isOpened()): 

     try: 
      cv2.imshow("Object Movement", frame_diff(prev_frame, cur_frame, next_frame)) 
      prev_frame = cur_frame 
      cur_frame = next_frame 
      next_frame = get_frame(cap) 
      differencesquared = (next_frame-cur_frame)**2 
      interframedifference = np.sum(differencesquared) 
      MIList.append(interframedifference) 
      print(interframedifference) 
      if interframedifference >= threshold: 
       out.write(cur_frame) 
       VideoFlag.append((str(intcurrentframenumber) + ' ' + '|' + ' ' + '1' + '\n')) 


      elif interframedifference < threshold: 
       VideoFlag.append((str(intcurrentframenumber) + ' ' + '|' + ' ' + '0' + ' \n')) 



      key = cv2.waitKey(1) 
      if key == ord('q'): 
       break 
     except: 
      break 

    with open((selectedvideo + 'flag' + '.txt'), 'w') as f: 
     for item in VideoFlag: 
      f.write((str(item) + '\n')) 
     print(VideoFlag) 


    cap.release() 
    cv2.destroyAllWindows() 

if __name__ == '__main__': 
    # this is called if this code was not imported ... ie it was directly run 
    # if this is called, that means there is no GUI already running, so we need to create a root 
    root = tk.Tk() 
    root.withdraw() 
    main()