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• Use FFMPEG to Save Live CCTV Video Streams that Has Wrong FPS Encoded, Published by Video Clips instead of Frames, and With Nonnegligible Frame Loss

  6 mars 2023, par Crear

  I want to use FFMPEG command line to archive live CCTV video stream (no audio) from Newark Citizen Virtual Patrol (https://cvp.newarkpublicsafety.org) for traffic analysis, previously I was using (I'm just a noob in these commands)
os.system('ffmpeg -t 24:00:00 -i '+address+' -hide_banner -c:v copy -s 640x360 -segment_time 00:15:00 -f segment -strftime 1 -reset_timestamps 1 "'+OutPath+camera_location+'_%Y-%m-%d-%H-%M-%S.mp4"') to archive the videos everyday and segment them into 15-min-long videos.

  


  However, there are several issues.

  


  

  1. The FPS read from the video stream is actually slower than it really is. For example, it's actually 12, but the decoded result says 8, so every time it generates a 15-min-long video, it only pasts 10 11 mins in the real world.

  


  2. Due to unstable frame loss, the FPS is not a stable value either. Therefore, when I manually set the FPS, it usually make the video has wrong length, and sometimes when the stream froze, it keeps waiting because it hasn't finished 15-min-long video. Something I noticed is that it may generate a 15-min-long video, which contains both night and day, started from perhaps 2AM but ended at 8AM.

  


  3. The live CCTV video stream is not frame by frame, but video clip by video clip. Therefore, when I set the -use_wallclock_as_timestamps to 1, the video will be ultra-fast playing the short video clip, then frozen for the rest of time until receiving next video clip.

  


  


  The only thing I can think of is to re-distribute the frames evenly between the timestamp of receiving the current video clip and the timestamp of receiving the prior video clip. What parameters can help FFMPEG to fix the FPS and archive correctly ? I am using FFMPEG to save the video instead of using OpenCV to decode the frame and then encode a video because we have huge amounts of cameras and our legacy Xeon processor had trouble encoding so many frames simultaneously.

  


  Any suggestion is appreciated !

  


• Getting garbled frames when exporting video to image sequence in FFMPEG

  28 janvier 2018, par film_guy01

  I’m very new to FFMPEG to go easy on me.

  So I’ve just started playing around with ffmpeg but I’m getting some promising results. But I keep getting images like this : https://i.imgur.com/wIMkVoV.jpg which is not what that image it supposed to look like (in case you were uncertain).

  here’s been my command line code :

  ffmpeg -i inputfile.mkv -q:v 1 -r 0.20 outputfile_%04d.jpg

  My input file is a .h264 compressed ultra high definition video saved as .mkv format.

  I’ll get error messages like this :

  [h264 @ 0x7fbccd84ce00] co located POCs unavailable
  
  [h264 @ 0x7fbccd81e200] error while decoding MB 45 61, bytestream -17 drop=406 speed=1.71x    
  
  [h264 @ 0x7fbccd81e200] concealing 17764 DC, 17764 AC, 17764 MV errors in P frame
  
  [h264 @ 0x7fbccd84ce00] co located POCs unavailable
  
  [h264 @ 0x7fbccd814400] reference picture missing during reorder
  
  [h264 @ 0x7fbccd814400] Missing reference picture, default is 65986
  
  [h264 @ 0x7fbccd814400] error while decoding MB 71 100, bytestream -26drop=598 speed=1.79x    
  
  [h264 @ 0x7fbccd814400] concealing 8378 DC, 8378 AC, 8378 MV errors in B frame
  
  [h264 @ 0x7fbccd81dc00] co located POCs unavailable
  
  [h264 @ 0x7fbccd81e200] co located POCs unavailable
  
  [h264 @ 0x7fbccd863200] co located POCs unavailable
  
  [h264 @ 0x7fbccd814400] error while decoding MB 43 116, bytestream -5 drop=710 speed=1.81x   

  Sometimes I get these errors as well, but I’m not sure they’re related.

  [h264 @ 0x7fbcce004c00] Stream #0: not enough frames to estimate rate; consider increasing probesize
  
  [swscaler @ 0x7fbccf0c8000] deprecated pixel format used, make sure you did set range correctly

  Any idea how to fix this problem and get ffmpeg to export the images cleanly ? This would be HUGE if I could figure out how to get this working.

  Thanks !

• Invalid too big FFmpeg Crop

  15 avril 2021, par cropperteam

  I have a video cropper working fine to all videos I tested, but a video from s20 ultra, gives me some error in FFmpeg, i don't really know if the video is oversize or not my source code https://github.com/rushidevmurari/RushiCropVideo/blob/213166834b0bc6ce83ab3f4ac494f261a57d7436/app/src/main/java/com/androworld/allinonevideoeditor/videocrop/VideoCropActivity.java

  


  I got these link but nothing good to my work Error when cropping video using FFMPEG

  


    [graph 0 input from stream 0:0 @ 0x7673807a4b40] sws_param option is deprecated and ignored
    [Parsed_crop_0 @ 0x7673807a4c80] Invalid too big or non positive size for width '3840' or height '1920'
    [Parsed_crop_0 @ 0x7673807a4c80] Failed to configure input pad on Parsed_crop_0
    Error reinitializing filters!
    Failed to inject frame into filter network: Invalid argument
    Error while processing the decoded data for stream #0:0
    Conversion failed!


  


  my command

  


  I/System.out: "-y" "-ss" "0" "-t" "31" "-i" "/storage/emulated/0/Download/20210227_175547.mp4" "-strict" "experimental" "-vf" "crop=w=3837:h=2160:x=1:y=-2070" "-r" "15" "-ab" "128k" "-vcodec" "mpeg4" "-acodec" "copy" "-b:v" "2500k" "-sample_fmt" "s16" "-ss" "0" "-t" "31" "/storage/emulated/0/VEditor/VideoCroper/20210227_175547-0-13.mp4"


  


  I/mobile-ffmpeg : Loading mobile-ffmpeg.

  


  my full log https://ghostbin.co/paste/s2qdw