Sur d’autres sites (3723)

• avfilter/vf_minterpolate : change the default threshold to get better scene change...

  20 septembre 2019, par Limin Wang

  avfilter/vf_minterpolate : change the default threshold to get better scene change detect result
   ./ffmpeg -loglevel debug -i ../fate-suite/svq3/Vertical400kbit.sorenson3.mov -vf
  
   minterpolate=fps=60:mi_mode=blend -an -f null -
  
   [Parsed_minterpolate_0 @ 0x7fe7f3e193c0] scene changed, input pts 1600
  
   [Parsed_minterpolate_0 @ 0x7fe7f3e193c0] scene changed, input pts 4120
  
   [Parsed_minterpolate_0 @ 0x7fe7f3e193c0] scene changed, input pts 5780
  
   [Parsed_minterpolate_0 @ 0x7fe7f3e193c0] scene changed, input pts 6700
  
   [Parsed_minterpolate_0 @ 0x7fe7f3e193c0] scene changed, input pts 8140
  
   [Parsed_minterpolate_0 @ 0x7fe7f3e193c0] scene changed, input pts 9740
  
   [Parsed_minterpolate_0 @ 0x7fe7f3e193c0] scene changed, input pts 14060
  
   [Parsed_minterpolate_0 @ 0x7fe7f3e193c0] scene changed, input pts 15680
  
   [Parsed_minterpolate_0 @ 0x7fe7f3e193c0] scene changed, input pts 18480
  
   [Parsed_minterpolate_0 @ 0x7fe7f3e193c0] scene changed, input pts 20020
  
   [Parsed_minterpolate_0 @ 0x7fe7f3e193c0] scene changed, input pts 21740
   The results are consistent with tests/ref/fate/filter-metadata-scenedetect
   For the master, it'll detect more than 20 scene change for the same source.
  Signed-off-by : Limin Wang <lance.lmwang@gmail.com>
  

  • [DH] doc/filters.texi
  • [DH] libavfilter/vf_minterpolate.c

• Fragmented mp4 file is not played by MSE

  19 mai 2020, par Daniel

  I created a fragmented mp4 file with ffmpeg (from h264), and removed the first 6 moof and mdat pairs.

  



  So now it still has the correct order of boxes : ftyp, moov, moof, mdat, moof, mdat, ..., but the first moof packet has the sequenceNumber of 7.

  



  VLC can play it fine, 'Movies & TV' can also play, but the first some seconds are black.

  



  If I drag the file into the browser, it can also play it fine.

  



  It is however not being displayed at all in the browser (Chrome) if I feed it via MSE.

  



  No error messages are printed, and in the media-internals' log it can be seen that the videoplayer starts playing in the first second and suspends it only in the 18th second :

  



  Timestamp   Property    Value
00:00:00.000    origin_url  "https://localhost:8443/"
00:00:00.000    kFrameUrl   "https://localhost:8443/websocket/videodemo.html"
00:00:00.000    kFrameTitle "WebSocket and MSE demo"
00:00:00.000    url "blob:https://localhost:8443/3b4d4b1a-7c08-4136-95fe-dabc14fba95f"
00:00:00.000    info    "ChunkDemuxer"
00:00:00.000    pipeline_state  "kStarting"
00:00:01.067    kVideoTracks    [{"alpha mode":"is_opaque","codec":"h264","coded size":"1600x900","color space":"{primaries:BT709, transfer:BT709, matrix:BT709, range:LIMITED}","encryption scheme":"Unencrypted","flipped":false,"has_extra_data":false,"natural size":"1600x900","profile":"h264 main","rotation":"0°","visible rect":"0,0 1600x900"}]
00:00:01.067    debug   "Video rendering in low delay mode."
00:00:01.070    info    "Using D3D11 device for DXVA"
00:00:01.075    kIsVideoDecryptingDemuxerStream false
00:00:01.075    kVideoDecoderName   "MojoVideoDecoder"
00:00:01.075    kIsPlatformVideoDecoder true
00:00:01.075    info    "Selected MojoVideoDecoder for video decoding, config: codec: h264, profile: h264 main, alpha_mode: is_opaque, coded size: [1600,900], visible rect: [0,0,1600,900], natural size: [1600,900], has extra data: false, encryption scheme: Unencrypted, rotation: 0°, flipped: 0, color space: {primaries:BT709, transfer:BT709, matrix:BT709, range:LIMITED}"
00:00:01.075    pipeline_state  "kPlaying"
00:00:01.067    duration    "unknown"
00:00:18.926    pipeline_state  "kSuspending"
00:00:18.926    pipeline_state  "kSuspended"
00:00:18.927    event   "SUSPENDED"


  



  Here is the video file for reference.

  



  What is the problem with this file, why is it not displayed in the browser with MSE ?

  


• How to record multiple screens and audio at once on MacBook using ffmpeg ?

  30 décembre 2019, par GeneralCode

  Task

  I want to be able to record three screens at one time, and record the microphone. Then combine the three recordings and the microphone recording into one output file.

  Detection of inputs

  The listing of both video and audio inputs can be found by using ffmpeg -f avfoundation -list_devices true -i "". This is can be found here.

  One Screen Recording

  I can record one of my three screens at a time by using ffmpeg -f avfoundation -i "3" -pix_fmt yuv420p -r 25 output.mov, where the "3" can be replaced with "1" or "2" to individually record one screen for 5 seconds. This is found at recording one screen for a duration of time.

  Post Process videos into one screen recording

  The most recent version of ffmpeg provides for combining multiple .mov files into one "stack". Stacking screen recordings discusses how to post process videos into one output file.

  Record audio

  The audio of the built in microphone or usb microphone can be recorded using ffmpeg -f avfoundation -i ":1" audiocapture.mp3. A description of this command can be found at recording audio with ffmpeg.

  What I want

  The following recorded until I hit q, with a good quality audio.

  ---------------------------------
  
  |               |               |
  
  |  1920 X 1080  |  1920 X 1080  |
  
  |               |               |
  
  ---------------------------------
  
      -----------------
  
      |               |
  
      |  2560 X 1600  |   
  
      |               |
  
      -----------------

  Current Progress

  This command :
  ffmpeg -f avfoundation -i "3" -pix_fmt yuv420p -r 25 -f avfoundation -i "2" -pix_fmt yuv420p -r 25 -f avfoundation -i "1" -pix_fmt yuv420p -r 25 -filter_complex "[0:v][1:v][2:v]xstack=inputs=3:layout=0_0|w0_0|0_h0[v]" -map "[v]" output.mov results in
  

  I am getting the message Thread message queue blocking; consider raising the thread_queue_size option (current value: 8), and do not know how to handle this. I also am not recording audio here.