Sur d’autres sites (16713)

• FFmpeg command to apply multiple filters and limit the final file size

  16 mars 2016, par Konrad — ffmpeg

  I’m using ffmpeg command below to convert video to a format of the defined scale and in order to hardcode the subtitles

  Original syntax

  ffmpeg -i "Original File.mov"  -vf subtitles=Subtitles.srt -vf scale=1920:1080 \
  
         -crf 12 "Final File".mov

  Problem

  I would like to expand this command further and :

  • ensure that the produce file is under 2GB
  • I would like to include additional parameters with advanced subtitle options, like setting the canvas size and fixing the potential delay

  Side notes

  I reckon that in case of predefining the file size the -crf 12 paramater will be redundant ?

• Revision c7846ebc34 : Use 8x8 DCT transform for I8X8 prediction mode Apply 2D-DCT transform of dimens

  1er août 2012, par Jingning Han

  Changed Paths : Modify /configure Modify /vp8/common/default_coef_probs.h Modify /vp8/common/entropy.h Modify /vp8/decoder/decodframe.c Modify /vp8/decoder/detokenize.c Modify /vp8/encoder/encodeintra.c Modify /vp8/encoder/rdopt.c Modify /vp8/encoder/tokenize.c Use 8x8 (...)

• Playing 120fps in browser between original and re-made video, original is normal speed, new video is slo-mo

  1er mars 2023, par Patrick Vellia

  I used my GoPro Hero10 to record at 4k 120fps on a green screen. This original video plays slo-mo in QuickTime but "normal" speed in the browser. I want it playing normal speed, and if end user wants to slow it down they have the extra frames for that to maintain clarity, which is why I record at 120.

  


  I then used FFMPEG to create an image sequence of the video.

  


  Then I ran Image Magic to create the transparent frames.

  


  Then I put it back together with the following command for a HEVC mov file :

  


  ffmpeg -r 120 -f image2 -i transparent/image_transparent_%08d.png -vcodec hevc_videotoolbox -crf 28 -alpha_quality 1  -tag:v hvc1 output.mov


  


  I am still on an Intel MacBook Pro running FFMPEG 4.6 (as I've found 5+ was buggy with one of my commands a few months ago but can't remember which one, I think it was the videotoolbox).

  


  The GoPro video has the following stream data as input to the FFMPEG :

  


  Duration: 00:00:08.15, start: 0.000000, bitrate: 60160 kb/s
  Stream #0:0(eng): Video: hevc (Main) (hvc1 / 0x31637668), yuvj420p(pc, bt709), 3840x2160 [SAR 1:1 DAR 16:9], 59891 kb/s, 119.88 fps, 119.88 tbr, 120k tbn, 119.88 tbc (default)
    Metadata:
      creation_time   : 2023-02-28T19:06:41.000000Z
      handler_name    : GoPro H.265
      vendor_id       : [0][0][0][0]
      encoder         : GoPro H.265 encoder
      timecode        : 19:05:32:105
  Stream #0:1(eng): Audio: aac (LC) (mp4a / 0x6134706D), 48000 Hz, stereo, fltp, 189 kb/s (default)
    Metadata:
      creation_time   : 2023-02-28T19:06:41.000000Z
      handler_name    : GoPro AAC  
      vendor_id       : [0][0][0][0]
      timecode        : 19:05:32:105
  Stream #0:2(eng): Data: none (tmcd / 0x64636D74), 0 kb/s (default)
    Metadata:
      creation_time   : 2023-02-28T19:06:41.000000Z
      handler_name    : GoPro TCD  
      timecode        : 19:05:32:105
  Stream #0:3(eng): Data: bin_data (gpmd / 0x646D7067), 76 kb/s (default)
    Metadata:
      creation_time   : 2023-02-28T19:06:41.000000Z
      handler_name    : GoPro MET  


  


  Whereas the re-constructed video has the following data :

  


  Duration: 00:00:08.13, start: 0.000000, bitrate: 763650 kb/s
  Stream #0:0: Video: hevc (Main) (hvc1 / 0x31637668), yuv420p(tv, progressive), 3840x2160 [SAR 1:1 DAR 16:9], 763696 kb/s, 120 fps, 120 tbr, 15360 tbn, 15360 tbc (default)
    Metadata:
      handler_name    : VideoHandler
      vendor_id       : FFMP
      encoder         : Lavc58.134.100 hevc_videotoolbo


  


  When this re-constructed video plays in the browser, it is in slow-mo and I need to set the playbackRate to 4.0 for it to play "normally".

  


  Is there something I need to add to the video for the browser to play it at "normal" speed ?