Sur d’autres sites (8391)

• Stream RTSP to HTML5 Video - which is the best approach ?

  13 janvier 2020, par Daniel

  As this task is very complicated I’ve created two approaches and I’d like to know which is the better approach for my purpose.

  Approach 1 :

  H264 frames are grabbed out of RTSP stream on the server (i.e. by ffmpeg), then they are put into a websocket and sent to the client. Client uses mp4box.js to fragment the h264 and then HTML5 video can render it with MSE.

  Approach 2 :

  H264 frames are grabbed out of RTSP stream and also fragmented on the server (i.e. by ffmpeg), then they are transferred directly to the client’s HTML5 video to render it with MSE.
  Here is an example for this approach.

  If we consider today’s client devices (modern phones, notebooks), we can state approach1 would be a better solution because it would prevent the central load on the server.

  However I have not really found any good resource or material on how to use approach1, hence I could not yet tried it out.

  I would like to know if approach1 is really better than approach2 ?

  because maybe grabbing and fragmenting would not put much higher load on the server than grabbing only

  (why I’m asking this ? because for approach2 I’ve a concrete example, whereas for approach1 I don’t. If approach1 is really better, I’ll go for it and implement the whole thing.)

  To put it more exact : does ffmpeg stress the server more if it grabs and fragments an rtsp-h264 stream to fmp4 than when it only grabs the frames from rtsp-h264 stream ?

• WebM Cabal

  8 octobre 2010, par Multimedia Mike — On2/Duck, VP8

  I traveled to a secret clubhouse today to take part in a clandestine meeting to discuss exactly how WebM will rule over all that you see and hear on the web. I can’t really talk about it. But I can show you the cool hat I got :

  
  
  Yeah, you’re jealous.
  

  The back of the hat has an Easter egg for video codec nerds– the original Duck Corporation logo (On2′s original name) :

  
  
  

  Former employees of On2 (now Googlers) were well-represented. It was an emotional day of closure as I met the person — the only person to date — who contacted me with a legal threat so many years ago. He still remembered me too.

  I met a lot of people involved in creating various Duck and On2 codecs and learned a lot of history and lore behind then– history I hope to be able to document one day.

  I’m glad I got that first rough draft of a toy VP8 encoder done in time for the meeting. It was the subject of much mirth.

• ffprobe not showing language tag for ASS files in Ubuntu

  9 juillet 2023, par Efraín

  This is something that has me totally lost, because I'm not sure what could I have done, but from one week to another, "language" stopped appearing in the tags of an ASS track on a MKV. I know this just started to appear, because just last week I ended working on an script to detect the language of tracks, and today that I decided to test it again, I noted that it started to fail, and from my debug it's because ffprobe is now printing this

  


  {
    "index": 2,
    "codec_name": "ass",
    "codec_long_name": "ASS (Advanced SSA) subtitle",
    "codec_type": "subtitle",
    "codec_tag_string": "[0][0][0][0]",
    "codec_tag": "0x0000",
    "r_frame_rate": "0/0",
    "avg_frame_rate": "0/0",
    "time_base": "1/1000",
    "start_pts": 0,
    "start_time": "0.000000",
    "duration_ts": 1430816,
    "duration": "1430.816000",
    "disposition": {
        "default": 1,
        "dub": 0,
        "original": 0,
        "comment": 0,
        "lyrics": 0,
        "karaoke": 0,
        "forced": 0,
        "hearing_impaired": 0,
        "visual_impaired": 0,
        "clean_effects": 0,
        "attached_pic": 0,
        "timed_thumbnails": 0
    },
    "tags": {
        "BPS-eng": "85",
        "DURATION-eng": "00:23:34.830000000",
        "NUMBER_OF_FRAMES-eng": "262",
        "NUMBER_OF_BYTES-eng": "15128",
        "_STATISTICS_WRITING_APP-eng": "mkvmerge v40.0.0 ('Old Town Road + Pony') 32-bit",
        "_STATISTICS_WRITING_DATE_UTC-eng": "2023-07-02 11:29:54",
        "_STATISTICS_TAGS-eng": "BPS DURATION NUMBER_OF_FRAMES NUMBER_OF_BYTES"
    }
}


  


  Where it should be a field called "language" in the "tags", like this(Note that other file types, like SRT, or audio tracks show it correctly)

  


  "tags": {
    "language": "eng",
    "BPS-eng": "128000",
    "DURATION-eng": "00:23:50.813000000",
    "NUMBER_OF_FRAMES-eng": "61620",
    "NUMBER_OF_BYTES-eng": "22893018",
    "_STATISTICS_WRITING_APP-eng": "mkvmerge v40.0.0 ('Old Town Road + Pony') 32-bit",
    "_STATISTICS_WRITING_DATE_UTC-eng": "2023-07-02 11:29:54",
    "_STATISTICS_TAGS-eng": "BPS DURATION NUMBER_OF_FRAMES NUMBER_OF_BYTES"
}


  


  The weird part is that is the same file I used for testing(And it worked), and I haven't edited it, so I'm not sure why is this happening, Does someone knows if I might have messed up something installing a library for another thing that might have caused it ?

  


  Just in case is necessary, this is the command I use : ffprobe -v quiet -print_format json -show_streams <file></file>