C++을 사용하는 Visual Studio의 OpenCV 비디오 파일에서 선택한 타이밍을 자르는 방법?

Question

5 분짜리 mp4 비디오 파일이 있습니다. 나는 2 분에서 3 분 사이에 줄이려고합니다.

예. Video1.mp4는 5 분 길이의 비디오이고, 출력은 Video1.mp4에서 2 분에서 3 분까지 포함하는 Video2.mp4라는 또 다른 파일이어야합니다.

아래 코드에서 무엇을 편집해야합니까? 도와주세요?

---

#include "stdafx.h"  //By default 

#include < string.h> 

#include < stdio.h> 

#include < stdlib.h> 

#include "cv.h" 

#include < highgui.h> 

#include "cxcore.h" 

#include <iostream>  //To use cout and cin 

using namespace cv;  //To use VideoCapture 

//Public file path 

string fullPath; 

VideoCapture capture(0); 


void ExplicitWM() 

{ 

//Explicit Watermark 

//Input Message 
char txt[100] = {'\0'}; 
cout << "Enter message to encode: " << endl; 
cout<<"-----------------------"<< endl; 
cin >> txt; 


double dWidth = capture.get(CV_CAP_PROP_FRAME_WIDTH); //get the width of frames of the video 
double dHeight = capture.get(CV_CAP_PROP_FRAME_HEIGHT); //get the height of frames of the video 

cout << "Frame Size = " << dWidth << "x" << dHeight << endl; 

Size frameSize(static_cast<int>(dWidth), static_cast<int>(dHeight)); 

//Save Video to desktop 
string userProfile = getenv("userprofile"); 
string path = userProfile + "\\Desktop\\"; 
string saveVid; 
getline (cin, saveVid); 
string fullPath = path + saveVid; 

//CV_FOURCC('P','I','M','1') is a MPEG-1 codec 
VideoWriter oVideoWriter (fullPath + "SavedVid.avi", CV_FOURCC('P', 'I', 'M', '1'), 30, frameSize, true); //initialize the VideoWriter object 

if (!oVideoWriter.isOpened()) //if not initialize the VideoWriter successfully, exit the program 
{ 
    cout << "ERROR: Failed to write the video" << endl; 
} 

while (capture.isOpened()) 
{ 
     Mat frame; 

     bool bSuccess = capture.read(frame); // read a new frame from video 

     imshow("Original Video", frame); //show the frame in "Original Video" window 

     Mat imgW = frame; 

     // cvScalar(255,255,255) = rgb 
     // cvPoint(40,40) = x-y cord 
     // 0.8 = font size 
     putText(imgW, txt, cvPoint(400,400), CV_FONT_HERSHEY_COMPLEX, 0.8, cvScalar(255,255,255), 1, CV_AA); 


     imshow("Watermarked Video", imgW); //show the frame of which watermark added 

     oVideoWriter.write(imgW); //write the frame into the file 

     if (waitKey(30) == 27) //wait for 'esc' key press for 30 ms. If 'esc' key is pressed, break loop 
     { 
       cout << "Esc key is pressed by user" << endl; 
       break; 
     } 
} 
} 

int main(int argc, char* argv[]) 

{ 

cout<< endl; 

cout << "Place video in Desktop and enter file name (e.g. vid.avi):" << endl; 

cout<<"--------------------------------------"<< endl; 

//Get user desktop file path 

string userProfile = getenv("userprofile"); //GetEnvironmentVariable() is to get current userprofile (e.g."C:\Users\L30807") 

string path = userProfile + "\\Desktop\\"; 

string vid; 

getline (cin, vid);  //Prompt to input file name 
fullPath = path + vid; 
capture.open(fullPath); //Read video 
cout<< endl; 

if (capture.isOpened()) 
{ 
    char choice; 
     cout<< "Choose option (a or b): "<< endl; 
     cout<<"-----------------------"<< endl; 
     cout<< "a.Encode Video "<<endl; 
     cout<< "b.Decode Video "<<endl; 
     cout<<"-----------------------"<< endl; 
     cin >> choice; 
     cout<< endl; 

     if (choice== 'a')//Encode Video 
     { 
      int choiceEn; 
      cout<< "Choose option (1 or 2): "<< endl; 
      cout<<"-----------------------"<< endl; 
      cout<< "1.Explicit Watermarking " <<endl; 
      cout<< "2.Implicit Watermarking(DCT) "<<endl; 
      cout<<"-----------------------"<< endl; 
      cin >> choiceEn; 
      cout<< endl; 

      switch (choiceEn) 
      { 
       case 1:   
       ExplicitWM(); 
       break; 

       default: 
       cout<<"Error: Wrong input. Exiting..." << endl; 
       return 0; 
      } 
     } 

     else if (choice== 'b') 
     { 

     } 
} 

Answer 1

• 변환 시작 시간 및

  start_frame_count = frame_per_sec * 60 * start_time_in_min를 이용하여 프레임 수를 시간 중지;
  stop_frame_count = frame_per_sec * 60 * stop_time_in_min;

• while 루프의 프레임 수.

• 카운트가 시작 또는 중지 프레임 카운트에 도달하는지 확인하십시오.

코드 모양 같은

,

stop_frame_count = int(stop_frame_count+0.5); 

frameCount=0; 

while(1) 
{ 
    frameCount++; 

    capture.read(frame); 

    if(frameCount >= start_frame_count && frameCount < stop_frame_count) 
    { 
     VideoWriter.write(frame); 
    } 

    else if(frameCount == stop_frame_count) 
    { 
     break; 
    } 
    } 
}