Sur d’autres sites (7408)

• ffmpeg progress is freezing frames when scene change

  19 août 2017, par Karol

  I’m capturing data from IP camera with RTSP protocol with ffmpeg with command :

  ffmpeg -rtsp_transport tcp -progress /media/kamip/stats.txt -i rtsp://192.168.1.220:554/live/h264/ch0 
  
  -c:v copy -c:a copy -strict 1 -map 0 -f segment -strftime 1 
  
  -segment_time 1800 /media/kamip/cam_%d_%m_%Y_%H_%M_%S.mkv

  I’m using this for 5 cameras. One is different type and it is in different location.
  Because ffmpeg does not support reconnect I’m writing status to /media/kamip/stats.txt file. In another script I’m parsing this output and every 30 seconds I’m checking if frame number changed, if yes - it is ok, if not, I’m restarting above command.

  The problem is only in the night. When is quite dark and suddenly lights on, for example when car is parking, the /media/kamip/stats.txt is showing the same frame number, so my script is recognizing this as a lost connection (video freeze)

  I tried "-strict 1" option and I think it is better (one false alarm per day instead of 10 per day), so I think this may be related to ffmpeg, not camera/video source, especially because the video is fine even frame number reported by ffmpeg is still the same. Also VLC does not have this kind of problem (but I cannot use it currently for this camera)

  I found that ffmpeg has build-in scene change detector, but it should works only when encoding video (I’m using "copy" option for audio and video) ?

  I’m thinking about different way of analyzing the video capturing, but this "-progress" in ffmpeg should works fine - and it is working fine for other cameras for few years).

  I also do not see any errors,
  when I encoded one cutted file with "-loglevel debug" I saw only information like below :

  [libx264 @ 0x25d77a0] scene cut at 174 Icost:2049115 Pcost:2006553 
  
  ratio:0.0208 bias:0.1387 gop:54 (imb:3186 pmb:168)

  ffmpeg in latest version

  ffmpeg version 3.3.3-1ubuntu1~16.04.york0 Copyright (c) 2000-2017 the FFmpeg developers
built with gcc 5.4.0 (Ubuntu 5.4.0-6ubuntu1~16.04.4) 20160609

  any help will be appreciated

• Encoding of two full hd streams in Linux + GPU with Intel HD4000 / VA API / FFMPEG / OpenGL

  27 juin 2017, par qknight

  i want to encode/stream two full hd streams in realtime from my laptop to a remote location using linux/xorg on the host.

  VA API

  for this i’ve been playing with the VA API but the performance is pretty bad with 5.59 fps (see paste below).

  FFMPEG

  using ffmpeg with CPU encoding i get about 200 fps but then all cores of my Intel(R) Core(TM) i7-3520M CPU @ 2.90GHz are busy and the fan turns on.

  future plans

  i want GPU support in encoding and later integrate this into a program which streams a virtual xorg ’screen’, see https://lastlog.de/wiki/index.php/Raspberry_PI_virtual_screen for more details on my plans.

  maybe h264 isn’t even what i want ? so if someone advices towards a different implementation, i’d welcome that.

  besides VA API there seems to be QuickSync but i didn’t experiment with that yet as it is not packaged on NixOS just yet.

  note : i need a library to have a smooth integration into the code.

  h264encode -w 1920 -h 1080 —profile MPSource frame is 1920x1080 and will code clip to 1920x1088 with crop
  INPUT:Try to encode H264...
  
  INPUT : Resolution : 1920x1080, 60 frames
  
  INPUT : FrameRate : 30
  
  INPUT : Bitrate : 14929920
  
  INPUT : Slieces : 1
  
  INPUT : IntraPeriod : 30
  
  INPUT : IDRPeriod : 60
  
  INPUT : IpPeriod : 1
  
  INPUT : Initial QP : 26
  
  INPUT : Min QP : 0
  
  INPUT : Source YUV : AUTO generated
  
  INPUT : Coded Clip : /tmp/test.264
  
  INPUT : Rec   Clip : Not save reconstructed frame
  libva info : VA-API version 0.38.1
  
  libva info : va_getDriverName() returns 0
  
  libva info : Trying to open /run/opengl-driver/lib/dri/i965_drv_video.so
  
  libva info : Found init function __vaDriverInit_0_38
  
  libva info : va_openDriver() returns 0
  
  Use profile VAProfileH264Main
  
  Support rate control mode (0x12):CBR CQP 
  
  RateControl mode : CQP
  
  Support VAConfigAttribEncPackedHeaders
  
  Support packed sequence headers
  
  Support packed picture headers
  
  Support packed slice headers
  
  Support packed misc headers
  
  Support 1 RefPicList0 and 1 RefPicList1
  
  Loading data into surface 15.....Complete surface loading
  
        \00000059(054456 bytes coded)
  PERFORMANCE :   Frame Rate : 5.59 fps (60 frames, 10730 ms (178.83 ms per frame))
  
  PERFORMANCE :   Compression ratio : 51:1
  
  PERFORMANCE :     UploadPicture : 10467 ms (174.45, 97.55% percent)
  
  PERFORMANCE :     vaBeginPicture : 0 ms (0.00, 0.00% percent)
  
  PERFORMANCE :     vaRenderHeader : 1 ms (0.02, 0.01% percent)
  
  PERFORMANCE :     vaEndPicture : 42 ms (0.70, 0.39% percent)
  
  PERFORMANCE :     vaSyncSurface : 244 ms (4.07, 2.27% percent)
  
  PERFORMANCE :     SavePicture : 7 ms (0.12, 0.07% percent)
  
  PERFORMANCE :     Others : -31 ms (71582787.75, 40027653.91% percent)
  
  (Multithread enabled, the timing is only for reference)
  

  i’ve seen https://www.reddit.com/r/linux/comments/1qk1yu/is_there_currently_opensource_software_to_encode/ though but i’m not sure what do do with it.

• Using FFMPEG : How to do a Scene Change Detection ? with timecode ?

  30 mai, par Mozart

  Based on this article it seems that it is possible to use FFMPEG to detect scene change in videos :
http://www.luckydinosaur.com/u/ffmpeg-scene-change-detector

  



  Now I have a video that displays a book text and when the text (word or sentence) is spoken it gets highlighted. 
Something like this audio book : https://youtu.be/lA7L6ZNVKjc

  



  I need to know the timestamp when the text gets highlighted (hence scene change), this will allow me to add timestamp tags on my youtube video, so it becomes easier for listeners to navigate through the audiobook.

  



  What is the magic command line that would do this ?

  



  Thank you very much !