Python 2.7/OpenCV 3.3：從立體攝像頭捕獲幀

Question

我使用的是Python 2.7和OpenCV 3.3，並且想要在每個定義的幀數或定義的秒數後從立體相機保存圖像。像每隔5幀或每2秒鐘後幀應存儲在不同的文件夾，如cam1folder和cam2folder。我能夠從兩臺相機捕捉視頻，然後使用這些視頻在預定義的秒後捕捉幀。下面給出了這些代碼。

import cv2 
import math 
import numpy as np 
videoFile = "output.avi" 
vidcap = cv2.VideoCapture(videoFile) 
success,image = vidcap.read() 

videoFile1 = "output1.avi" 
vidcap1 = cv2.VideoCapture(videoFile1) 
success1,image1 = vidcap1.read() 

seconds = 3 
fps = vidcap.get(cv2.CAP_PROP_FPS) # Gets the frames per second 
multiplier = fps * seconds 
fps1 = vidcap1.get(cv2.CAP_PROP_FPS) # Gets the frames per second 
multiplier1 = fps1 * seconds 


while success: 
    frameId = int(round(vidcap.get(1))) #current frame number, rounded b/c sometimes you get frame intervals which aren't integers...this adds a little imprecision but is likely good enough 
    success, image = vidcap.read() 

    frameId1 = int(round(vidcap1.get(1))) #current frame number 
    success1, image1 = vidcap1.read() 

    if frameId % multiplier == 0: 
     cv2.imwrite("right/rframe%d.jpg" % frameId, image) # stored in right folder 
    if frameId1 % multiplier1 == 0: 
     cv2.imwrite("left/lframe%d.jpg" % frameId1, image1) # stored in left folder 


vidcap.release() 
vidcap1.release() 
print "Complete" 

但我想直接是圖像的實時採集來自視頻而不保存這些：用於保存視頻之後，從兩個攝像頭捕獲幀

import numpy as np 
import cv2 
cap = cv2.VideoCapture(0) 
cap1 = cv2.VideoCapture(1) 
fourcc = cv2.VideoWriter_fourcc(*'MJPG') 
out = cv2.VideoWriter('output.avi',fourcc, 20.0, (640,480)) 
out1 = cv2.VideoWriter('output1.avi',fourcc, 20.0, (640,480)) 

while(True): 
    ret, frame = cap.read() 
    ret1, frame1 = cap1.read() 
    gray = cv2.cvtColor(frame, cv2.COLOR_BGR2GRAY) 
    out.write(frame) 
    out1.write(frame1) 
    cv2.imshow('frame',gray) 
    cv2.imshow('frame1', frame1) 
    if cv2.waitKey(1) & 0xFF == ord('q'): 
     break 

cap.release() 
out.release() 
cap1.release() 
out1.release() 
cv2.destroyAllWindows() 

代碼：

用於視頻捕捉代碼視頻，但保存捕獲的圖像在兩個不同的文件夾。這個怎麼做？

謝謝。

Answer 1

你只需要合併你自己寫的2個代碼片段即可。

在您的第一個代碼片段中，當您運行while循環時，您可以維護一個公用計數器，而不用單獨的攝像機使用不同的計數器。當您的計數器達到所需值時（根據您的問題，5幀），您直接在frame和frame1對象上執行imwrite。

您不需要中間對象VideoWriter。 你的最終代碼看起來像這樣：

cap = cv2.VideoCapture(0) 
cap1 = cv2.VideoCapture(1) 
multiplier = 5 
frame_count = 0 
while(True): 
    frame_count += 1 
    ret, frame = cap.read() 
    ret1, frame1 = cap1.read() 

    cv2.imshow('frame',frame) #show all frames 
    cv2.imshow('frame1', frame1) 

    if frame_count % multiplier == 0: 
     cv2.imwrite("right/rframe%d.jpg" % frame_count, frame) #write specific frames 
     cv2.imwrite("left/lframe%d.jpg" % frame_count, frame1) 

    if cv2.waitKey(1) & 0xFF == ord('q'): 
     break