Recherche avancée

Sur d’autres sites (10503)

• How to segment a video file (using FFMPEG) to "encoded" version (i.e., .mp4 is downloaded from one our CDN servers) in which each chunk must be 4MB ?

  13 janvier 2019, par Danyal Zia

  I am using FFMPEG command-line/terminal tool. I have a video in .mp4 format. I am well educated on the segmentation of videos in terms of length/duration, however, I want to segment the chunks of the "encoded/transcoded" version of the video (which I downloaded from our CDN in.mp4) to 4MB (4000000 Bytes), except the last one, which will vary in size (i.e., to encode/decode the video fully). If I am having trouble explaining what I am seeking, then just know I have no interest in segmenting the video in terms of duration/length, as this is irrelevant for me.

  To explain the scenario : I have two copies of the same video. The one is "original" and the second video is the one that I downloaded from the server/CDN. The second video turns out to be corrupted (despite the fact that the video is downloaded successfully, and has the same length/duration) ; it stops playing around 1:12 minutes, even though the seeker/slider keeps progressing until somewhere around 1:45 minutes where the video and audio start to work again.

  I have done the binary comparison (using "fc" in CMD) of these two videos, and they are not the same at all.

  In a nutshell : I think I need to "encode" the corrupted .mp4 video, and then segment the encoded data to multiple versions of 4MB. I don’t know how can I do it from FFMPEG.

  If anything isn’t clear, then ask as many questions you want.

  Thank you for reading !

  Edit : The following seems to work, however, not all the chunks are equivalent to 4MB. What is a something I am doing the wrong way ?

  ffmpeg -i "original.mp4" -b:v 1000000 -g 60 -hls_time 2 -hls
_list_size 0 -hls_segment_size 4000000 output.m3u8

• FFMPEG - Is there a way to remove "metadata" from .MKVs ?

  1er janvier 2019, par smirnoval

  I’ve got a Matroska Media Container file (.MKV) ; summarizing it with "MediaInfo" shows it’s gotten a few text streams (I guess they’re subtitles, although they’re not shown during VLC Media Player playback), and summarizing it with MKVToolNix shows all these ’substitles’ along other weird entries.

  I know I can use the latter program to actually "save" the .MKV file without unnecessary data (everything except the Video and Audio), but I’ve never been a fan of those kinds of tools and would like to know if there’s actually a way to remove unnecessary data with FFMPEG’s command lines. All I need is the Video and Audio datas in the .MKV to later convert it into either a HEVC or AVC codec containers.
  (if there’s a command that can do all that in one go, please let me know)

  Thanks a lot.

• lavf/rawdec : Do not mark streams from raw subtitle demuxers as data streams.

  27 novembre 2018, par Carl Eugen Hoyos

  lavf/rawdec : Do not mark streams from raw subtitle demuxers as data streams.
  Improves "ffmpeg -i" output for raw dvbsub files.
  

  • [DH] libavformat/rawdec.c
  • [DH] libavformat/rawdec.h
  • [DH] libavformat/version.h