Recherche avancée

Sur d’autres sites (10517)

• Video file not opening ?(opencv 3.1.0 windows)

  6 juin 2016, par SumanaSusmitha

  import cv2 
  
  cap = cv2.VideoCapture("StopMoti2001.mpeg")
  
  if cap.isOpened():
  
      print 'fine'
  
  else:
  
      print 'not fine'

  output is ’not fine’ I have checked for various videos and I also moved the ffmpeg file moving to PATH and still the problem remains same. can you please suggest a solution

• How to take a screenshot of desktop fast with Java in Windows (ffmpeg, etc.) ?

  4 mars 2015, par Setsuna

  I would like to use java to take a screenshot of my machine using FFMPEG or some other solution. I know linux works with ffmpeg without JNI, but running it in Windows does not work and may require (JNI ?) is there any sample of some simple Java class (and anything else necessary) to capture a screenshot runnable in a windows environment ? Is there some alternative to FFMPEG ? I want to take screenshot at a rate faster than the Java Robot API, which I have found to work at taking screenshots, but is slower than I would like.

  I know in Linux this works very fast :

  import com.googlecode.javacv.*;
  
  
  
  public class ScreenGrabber {
  
      public static void main(String[] args) throws Exception {
  
          int x = 0, y = 0, w = 1024, h = 768;
  
          FFmpegFrameGrabber grabber = new FFmpegFrameGrabber(":0.0+" + x + "," + y);
  
          grabber.setFormat("x11grab");
  
          grabber.setImageWidth(w);
  
          grabber.setImageHeight(h);
  
          grabber.start();
  
  
  
          CanvasFrame frame = new CanvasFrame("Screen Capture");
  
          while (frame.isVisible()) {
  
              frame.showImage(grabber.grab());
  
          }
  
          frame.dispose();
  
          grabber.stop();
  
      }

  This does not work in windows environment. Am not sure if there is some way I could use this same code, but use javacpp to actually get it working without having to change much of the above code.

  Goal is to take screenshots of screen fast, but then stop after it takes a screenshot that is "different", aka. screen changed because of some event like, a window is window closed, etc.

• OpenCV cv2 not working in Windows 7

  6 septembre 2014, par Subhendu Sinha Chaudhuri

  I have a Windows 7 SP1 64 Bit machine with open cv2.4.9 installed and python 2.7.6 installed.
  I use pre compiled version of opencv

  The following code works perfectly for me

  import cv2.cv as cv
  
  import time
  
  
  
  cv.NamedWindow("camera", 0)
  
  
  
  capture = cv.CaptureFromCAM(0)
  
  
  
  while True:
  
      img = cv.QueryFrame(capture)
  
      cv.ShowImage("camera", img)
  
      if cv.WaitKey(10) == 27:
  
          break
  
  cv.DestroyAllWindows()

  Now when I try to use this code

  import cv2
  
  import numpy as np
  
  cam = cv2.VideoCapture(0)
  
  s, img = cam.read()
  
  
  
  winName = "Movement Indicator"
  
  cv2.namedWindow(winName, cv2.CV_WINDOW_AUTOSIZE)
  
  
  
  while s:
  
    cv2.imshow( winName,img )
  
  
  
    s, img = cam.read()
  
  
  
    key = cv2.waitKey(10)
  
    if key == 27:
  
      cv2.destroyWindow(winName)
  
      break
  
  
  
  print "Goodbye"

  The window is opened , the camera is initialized (as camera lights are on) , but nothing is displayed and the window closes and the program exits.

  WHERE am I going wrong ??

  QUESTION 2
  Can any one also suggest me how to capture live video stream from my Linux machine 192.168.1.3 . The stream is being generated by ffmpeg.

  The video stream can be opened in web browser. But I want to capture it with opencv and python.