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• Problems with video playback using the ffplay

  7 octobre 2023, par Anzor Gergov

  everyone. I have problems with video playback using the ffplay. Used the following command

  



  ffplay -i input.avi


  



  But the following error occurred.

  



  ffplay version N-87353-g183fd30 Copyright (c) 2003-2017 the FFmpeg developers
  built with gcc 7.2.0 (GCC)
  configuration: --disable-static --enable-shared --enable-gpl --enable-version3 --enable-cuda --enable-cuvid --enable-d3d11va --enable-dxva2 --enable-libmfx --enable-nvenc --enable-avisynth --enable-bzlib --enable-fontconfig --enable-frei0r --enable-gnutls --enable-iconv --enable-libass --enable-libbluray --enable-libbs2b --enable-libcaca --enable-libfreetype --enable-libgme --enable-libgsm --enable-libilbc --enable-libmodplug --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenh264 --enable-libopenjpeg --enable-libopus --enable-librtmp --enable-libsnappy --enable-libsoxr --enable-libspeex --enable-libtheora --enable-libtwolame --enable-libvidstab --enable-libvo-amrwbenc --enable-libvorbis --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxavs --enable-libxvid --enable-libxml2 --enable-libzimg --enable-lzma --enable-zlib
  libavutil      55. 76.100 / 55. 76.100
  libavcodec     57.106.101 / 57.106.101
  libavformat    57. 82.101 / 57. 82.101
  libavdevice    57.  8.101 / 57.  8.101
  libavfilter     6.105.100 /  6.105.100
  libswscale      4.  7.103 /  4.  7.103
  libswresample   2.  8.100 /  2.  8.100
  libpostproc    54.  6.100 / 54.  6.100
[avi @ 00000000024bd9e0] Could not find codec parameters for stream 0 (Video: none (HEVC / 0x43564548), none, 1920x1080, 1697 kb/s): unknown codec
Consider increasing the value for the 'analyzeduration' and 'probesize' options
Input #0, avi, from 'c:\problem.avi':
  Duration: 00:00:25.00, start: 0.000000, bitrate: 1701 kb/s
    Stream #0:0: Video: none (HEVC / 0x43564548), none, 1920x1080, 1697 kb/s, 30.92 fps, 30.92 tbr, 30.92 tbn, 30.92 tbc
No codec could be found with id 0
Failed to open file 'c:\problem.avi' or configure filtergraph


  



  This video is playable without any problems via the VLC, Media Player Classic. 
After trying to find out more information about the video file, I used ffprobe command

  



  ffprobe -v 0  c:\problem.avi -print_format json -show_format -show_streams

{
    "streams": [
        {
            "index": 0,
            "codec_type": "video",
            "codec_tag_string": "HEVC",
            "codec_tag": "0x43564548",
            "width": 1920,
            "height": 1080,
            "has_b_frames": 0,
            "sample_aspect_ratio": "0:1",
            "display_aspect_ratio": "0:1",
            "level": -99,
            "r_frame_rate": "773/25",
            "avg_frame_rate": "773/25",
            "time_base": "25/773",
            "start_pts": 0,
            "start_time": "0.000000",
            "duration_ts": 773,
            "duration": "25.000000",
            "bit_rate": "1697304",
            "nb_frames": "773",
            "disposition": {
                "default": 0,
                "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
            }
        }
    ],
    "format": {
        "filename": "c:\\bin\\Virtual\\problem\\problem.avi",
        "nb_streams": 1,
        "nb_programs": 0,
        "format_name": "avi",
        "format_long_name": "AVI (Audio Video Interleaved)",
        "start_time": "0.000000",
        "duration": "25.000000",
        "size": "5318210",
        "bit_rate": "1701827",
        "probe_score": 100
    }
}


  



  What could be the problem with this videofile ?

  


• How can I programmatically write and read random video watermarks ?

  13 novembre 2017, par GreenTriangle

  I spent a few minutes trying to think of a clearer way to word my title, but I couldn’t manage it, sorry.

  I want to essentially canary trap video files : I am (hypothetically, this is not real but a personal exercise) offering them up to 5,000 different people, and if one gets leaked, I want to know who leaked it. Metadata is too easily emoved, so what I’d like to do is add a random and subtle watermark to each file, and store information about that in a database.

  For example : on Joe Smith’s copy, a 10x10 pixel 80% transparent red square in the upper left corner for 5 frames. On Diane Brown’s copy, a full-width 5-pixel 90% transparent black bar on the bottom edge for 15 frames. Then, if I find a leaked copy, I could check it against the database.

  I know this still isn’t foolproof : cropping would break co-ordinates, hue/brightness transforms would break colour reading, cutting time would break timestamps. But if I did want to do this anyway, what would be a good strategy for it ?

  My idea was to generate PNG overlays randomly, split the video into parts with mkvtoolnix/ffmpeg, re-encode the middle part with ffmpeg + overlay filter, and then rejoin them. But is this silly when there’s a "proper" way to do it ? And what would I be doing to read the watermarks, which I can’t even really conceive of ?

• Use FFmpeg for continuous streaming from other source

  28 septembre 2017, par widgg

  We have an app that pipes its output, and its output is compress H264 data. The source of the data is from a 3d engine running in same app.

  We can easily pipe the output in FFmpeg to save as mp4 or even m3u8.

  It’s also possible to turn FFmpeg as a server to feed video files.

  So our objective is to have FFmpeg read that data, convert into into mp4 or m3u8 internally and then stream so that it can be read in the web browser.

  We don’t care about be able to replay some file, go back in time or whatever, we just care about the current value.

  Is there a way to do that ? Or a similar solution that would allow some close to that.

  Thanks

  I guess, if it’s possible, it’s like wanting to stream your personal webcam into the web browser. Then you could connect to that and see what is happening at home or wherever your webcam is.