Recherche avancée

Sur d’autres sites (12277)

• How to obtain time markers for video splitting using python/OpenCV

  30 mars 2016, par Bleddyn Raw-Rees

  Hi I’m new to the world of programming and computer vision so please bare with me.

  I’m working on my MSc project which is researching automated deletion of low value content in digital file stores. I’m specifically looking at the sort of long shots that often occur in natural history filming whereby a static camera is left rolling in order to capture the rare snow leopard or whatever. These shots may only have some 60s of useful content with perhaps several hours of worthless content either side.

  As a first step I have a simple motion detection program from Adrian Rosebrock’s tutorial [http://www.pyimagesearch.com/2015/05/25/basic-motion-detection-and-tracking-with-python-and-opencv/#comment-393376]. Next I intend to use FFMPEG to split the video.

  What I would like help with is how to get in and out points based on the first and last points that motion is detected in the video.

  Here is the code should you wish to see it...

  # import the necessary packages
  
  import argparse
  
  import datetime
  
  import imutils
  
  import time
  
  import cv2
  
  
  
  # construct the argument parser and parse the arguments
  
  ap = argparse.ArgumentParser()
  
  ap.add_argument("-v", "--video", help="path to the video file")
  
  ap.add_argument("-a", "--min-area", type=int, default=500, help="minimum area size")
  
  args = vars(ap.parse_args())
  
  
  
  # if the video argument is None, then we are reading from webcam
  
  if args.get("video", None) is None:
  
  camera = cv2.VideoCapture(0)
  
  time.sleep(0.25)
  
  
  
  # otherwise, we are reading from a video file
  
  else:
  
      camera = cv2.VideoCapture(args["video"])
  
  
  
  # initialize the first frame in the video stream
  
  firstFrame = None
  
  
  
  # loop over the frames of the video
  
  while True:
  
      # grab the current frame and initialize the occupied/unoccupied
  
      # text
  
      (grabbed, frame) = camera.read()
  
      text = "Unoccupied"
  
  
  
      # if the frame could not be grabbed, then we have reached the end
  
      # of the video
  
      if not grabbed:
  
          break
  
  
  
      # resize the frame, convert it to grayscale, and blur it
  
      frame = imutils.resize(frame, width=500)
  
      gray = cv2.cvtColor(frame, cv2.COLOR_BGR2GRAY)
  
      gray = cv2.GaussianBlur(gray, (21, 21), 0)
  
  
  
      # if the first frame is None, initialize it
  
      if firstFrame is None:
  
          firstFrame = gray
  
          continue
  
  
  
      # compute the absolute difference between the current frame and
  
      # first frame
  
      frameDelta = cv2.absdiff(firstFrame, gray)
  
      thresh = cv2.threshold(frameDelta, 25, 255, cv2.THRESH_BINARY)[1]
  
  
  
      # dilate the thresholded image to fill in holes, then find contours
  
      # on thresholded image
  
      thresh = cv2.dilate(thresh, None, iterations=2)
  
      (_, cnts, _) = cv2.findContours(thresh.copy(), cv2.RETR_EXTERNAL, cv2.CHAIN_APPROX_SIMPLE)
  
  
  
      # loop over the contours
  
      for c in cnts:
  
          # if the contour is too small, ignore it
  
          if cv2.contourArea(c) < args["min_area"]:
  
              continue
  
  
  
          # compute the bounding box for the contour, draw it on the frame,
  
          # and update the text
  
          (x, y, w, h) = cv2.boundingRect(c)
  
          cv2.rectangle(frame, (x, y), (x + w, y + h), (0, 255, 0), 2)
  
          text = "Occupied"
  
  
  
      # draw the text and timestamp on the frame
  
      cv2.putText(frame, "Room Status: {}".format(text), (10, 20),
  
          cv2.FONT_HERSHEY_SIMPLEX, 0.5, (0, 0, 255), 2)
  
      cv2.putText(frame, datetime.datetime.now().strftime("%A %d %B %Y %I:%M:%S%p"),
  
          (10, frame.shape[0] - 10), cv2.FONT_HERSHEY_SIMPLEX, 0.35, (0, 0, 255), 1)
  
  
  
      # show the frame and record if the user presses a key
  
      cv2.imshow("Security Feed", frame)
  
      cv2.imshow("Thresh", thresh)
  
      cv2.imshow("Frame Delta", frameDelta)
  
      key = cv2.waitKey(1) & 0xFF
  
  
  
      # if the `q` key is pressed, break from the lop
  
      if key == ord("q"):
  
          break
  
  
  
  # cleanup the camera and close any open windows
  
  camera.release()
  
  cv2.destroyAllWindows()

  Thanks !

• a gcc strange ld error when compile some ffmpeg application, libvorbisenc package not found

  8 mai 2016, par ldkxingzhe

  I follow the ffmpeg tuorial, and install ffmpeg via ppa

  But when I compiled the tuorial02.c, I got gcc error :

  /usr/bin/ld : /opt/ffmpeg/lib//libavcodec.a(libvorbisenc.o) : undefined reference to symbol ’vorbis_encode_setup_vbr’

  //usr/lib/x86_64-linux-gnu/libvorbisenc.so.2 : error adding symbols : DSO missing from command line
  collect2 : error : ld returned 1 exit status

  My compile command is :

  gcc -I /opt/ffmpeg/include/ -L /opt/ffmpeg/lib/  -o tutorial02 tutorial02.c -lavformat -lavcodec -lswscale `sdl-config --cflags --libs`  -lpthread -lz -lm -ldl

  I have searched the reason for hours. I can’t solve this. Can anyone help me ?

  Added I have add -lvorbisenc to the end. the error is lib not found. and libvorivisenc2 has been install. so this question is not a duplicate of Strange linking error : DSO missing from command line

  And My OS is Linux mint 17.3

• Mirror not found when trying to install FFMPEG on CENTOS7

  31 octobre 2016, par Peter

  I’m on a dedicated server with Root access. not familiar with servers. Im trying to install FFMpeg on my server but following online instructions I’m getting errors can’t figure out how to solve it. So any light on this will be very appreciated.

  [root@ns335004 ~]# yum update
  
  base                                                                                                           | 3.6 kB  00:00:00     
  
  http://apt.sw.be/redhat/el7/en/x86_64/dag/repodata/repomd.xml: [Errno 14] HTTP Error 404 - Not Found
  
  Trying other mirror.
  
  To address this issue please refer to the below knowledge base article 
  
  
  
  https://access.redhat.com/articles/1320623
  
  
  
  If above article doesn't help to resolve this issue please create a bug on https://bugs.centos.org/
  
  
  
  
  
  
  
   One of the configured repositories failed (DAG RPM Repository),
  
   and yum doesn't have enough cached data to continue. At this point the only
  
   safe thing yum can do is fail. There are a few ways to work "fix" this:
  
  
  
       1. Contact the upstream for the repository and get them to fix the problem.
  
  
  
       2. Reconfigure the baseurl/etc. for the repository, to point to a working
  
          upstream. This is most often useful if you are using a newer
  
          distribution release than is supported by the repository (and the
  
          packages for the previous distribution release still work).
  
  
  
       3. Disable the repository, so yum won't use it by default. Yum will then
  
          just ignore the repository until you permanently enable it again or use
  
          --enablerepo for temporary usage:
  
  
  
              yum-config-manager --disable dag
  
  
  
       4. Configure the failing repository to be skipped, if it is unavailable.
  
          Note that yum will try to contact the repo. when it runs most commands,
  
          so will have to try and fail each time (and thus. yum will be be much
  
          slower). If it is a very temporary problem though, this is often a nice
  
          compromise:
  
  
  
              yum-config-manager --save --setopt=dag.skip_if_unavailable=true
  
  
  
  failure: repodata/repomd.xml from dag: [Errno 256] No more mirrors to try.
  
  http://apt.sw.be/redhat/el7/en/x86_64/dag/repodata/repomd.xml: [Errno 14] HTTP Error 404 - Not Found

  repolist

  [root@ns335004 ~]# yum repolist all
  
  http://apt.sw.be/redhat/el7/en/x86_64/dag/repodata/repomd.xml: [Errno 14] HTTP Error 404 - Not Found
  
  Trying other mirror.
  
  To address this issue please refer to the below knowledge base article 
  
  
  
  https://access.redhat.com/articles/1320623
  
  
  
  If above article doesn't help to resolve this issue please create a bug on https://bugs.centos.org/
  
  
  
  http://apt.sw.be/redhat/el7/en/x86_64/dag/repodata/repomd.xml: [Errno 14] HTTP Error 404 - Not Found
  
  Trying other mirror.
  
  repo id                                  repo name                                                                     status
  
  C7.0.1406-base/x86_64                    CentOS-7.0.1406 - Base                                                        disabled
  
  C7.0.1406-centosplus/x86_64              CentOS-7.0.1406 - CentOSPlus                                                  disabled
  
  C7.0.1406-extras/x86_64                  CentOS-7.0.1406 - Extras                                                      disabled
  
  C7.0.1406-fasttrack/x86_64               CentOS-7.0.1406 - CentOSPlus                                                  disabled
  
  C7.0.1406-updates/x86_64                 CentOS-7.0.1406 - Updates                                                     disabled
  
  C7.1.1503-base/x86_64                    CentOS-7.1.1503 - Base                                                        disabled
  
  C7.1.1503-centosplus/x86_64              CentOS-7.1.1503 - CentOSPlus                                                  disabled
  
  C7.1.1503-extras/x86_64                  CentOS-7.1.1503 - Extras                                                      disabled
  
  C7.1.1503-fasttrack/x86_64               CentOS-7.1.1503 - CentOSPlus                                                  disabled
  
  C7.1.1503-updates/x86_64                 CentOS-7.1.1503 - Updates                                                     disabled
  
  base/7/x86_64                            CentOS-7 - Base                                                               enabled:  9,007
  
  base-debuginfo/x86_64                    CentOS-7 - Debuginfo                                                          disabled
  
  base-source/7                            CentOS-7 - Base Sources                                                       disabled
  
  c7-media                                 CentOS-7 - Media                                                              disabled
  
  centosplus/7/x86_64                      CentOS-7 - Plus                                                               disabled
  
  centosplus-source/7                      CentOS-7 - Plus Sources                                                       disabled
  
  cr/7/x86_64                              CentOS-7 - cr                                                                 disabled
  
  dag/7/x86_64                             DAG RPM Repository                                                            enabled:      0
  
  epel/x86_64                              Extra Packages for Enterprise Linux 7 - x86_64                                enabled: 10,764
  
  epel-debuginfo/x86_64                    Extra Packages for Enterprise Linux 7 - x86_64 - Debug                        disabled
  
  epel-source/x86_64                       Extra Packages for Enterprise Linux 7 - x86_64 - Source                       disabled
  
  epel-testing/x86_64                      Extra Packages for Enterprise Linux 7 - Testing - x86_64                      disabled
  
  epel-testing-debuginfo/x86_64            Extra Packages for Enterprise Linux 7 - Testing - x86_64 - Debug              disabled
  
  epel-testing-source/x86_64               Extra Packages for Enterprise Linux 7 - Testing - x86_64 - Source             disabled
  
  extras/7/x86_64                          CentOS-7 - Extras                                                             enabled:    393
  
  extras-source/7                          CentOS-7 - Extras Sources                                                     disabled
  
  fasttrack/7/x86_64                       CentOS-7 - fasttrack                                                          disabled
  
  nux-dextop/x86_64                        Nux.Ro RPMs for general desktop use                                           disabled
  
  nux-dextop-testing/x86_64                Nux.Ro RPMs for general desktop use - testing                                 disabled
  
  plesk-php-5.6                            PHP v 5.6 for Plesk - x86_64                                                  enabled:     31
  
  plesk-php-7.0                            PHP v 7.0 for Plesk - x86_64                                                  enabled:     28
  
  updates/7/x86_64                         CentOS-7 - Updates                                                            enabled:  2,560
  
  updates-source/7                         CentOS-7 - Updates Sources                                                    disabled
  
  repolist: 22,783

  I also tried :

  sudo yum clean metadata
  
  sudo yum clean all

  But still having same 404 Error.

  Thanks.