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• Filter text disappearing after concat, why ?

  15 août 2018, par GemmaB89

  I'm trying to concatenate 2 videos, while at the same time adding some text to the second one. I'm using php-ffmpeg to do this, with the Sharapov extension, but I have the actual ffmpeg commands.

  To do this it seems to encode the first video, then the second one with the text separately, and then joins them together. Problem is the text appears in the encoded (but un-joined) second video, but as soon as they are joined together it disappears.

  Here are the commands:

  ffmpeg '-y' '-i' 'video_in/first_vid.mp4' '-threads' '8' '-vcodec' 'libx264' '-acodec' 'aac' '-max_muxing_queue_size' '400' '-b:v' '1000k' '-refs' '6' '-coder' '1' '-sc_threshold' '40' '-flags' '+loop' '-me_range' '16' '-subq' '7' '-i_qfactor' '0.71' '-qcomp' '0.6' '-qdiff' '4' '-trellis' '1' '-b:a' '256k' '-ac' '2' '-pass' '1' '-passlogfile' '/tmp/ffmpeg-passes5b73814fa1e29qjif7/pass-5b73814fa1f5b' '/data/tmp/ffmpeg-7a580007c010377da19305b0836e7a4d-5b73814f9ff35.mp4'
  
      2%    2%    2%    4%    4%    6%    6%    6%    8%    8%    10%    10%    10%    12%    12%    12%    14%    14%    14%    16%    16%    18%    18%    18%    20%    20%    22%    22%    22%    24%    24%    24%    26%    26%    26%    28%    28%    28%    30%    30%    30%    32%    32%    34%    34%    34%    36%    36%    36%    38%    38%    38%    40%    40%    40%    42%    44%    44%    44%    46%    46%    46%    48%    48%    48%
  
  ffmpeg '-y' '-i' 'video_in/first_vid.mp4' '-threads' '8' '-vcodec' 'libx264' '-acodec' 'aac' '-max_muxing_queue_size' '400' '-b:v' '1000k' '-refs' '6' '-coder' '1' '-sc_threshold' '40' '-flags' '+loop' '-me_range' '16' '-subq' '7' '-i_qfactor' '0.71' '-qcomp' '0.6' '-qdiff' '4' '-trellis' '1' '-b:a' '256k' '-ac' '2' '-pass' '2' '-passlogfile' '/tmp/ffmpeg-passes5b73814fa1e29qjif7/pass-5b73814fa1f5b' '/data/tmp/ffmpeg-7a580007c010377da19305b0836e7a4d-5b73814f9ff35.mp4'
  
      50%    50%    50%    52%    52%    52%    52%    52%    52%    54%    54%    54%    54%    54%    54%    56%    56%    56%    56%    56%    56%    58%    58%    58%    58%    58%    58%    60%    60%    60%    60%    60%    60%    62%    62%    62%    62%    62%    62%    64%    64%    64%    64%    64%    66%    66%    66%    66%    66%    66%    66%    68%    68%    68%    68%    68%    70%    70%    70%    70%    70%    72%    72%    72%    72%    72%    72%    72%    74%    74%    74%    74%    74%    74%    74%    76%    76%    76%    76%    76%    76%    76%    78%    78%    78%    78%    78%    78%    80%    80%    80%    80%    80%    80%    82%    82%    82%    82%    82%    84%    84%    84%    84%    84%    84%    84%    84%    84%    84%    86%    86%    86%    86%    86%    86%    88%    88%    88%    88%    88%    88%    88%    90%    90%    90%    90%    90%    90%    90%    90%    92%    92%    92%    92%    94%    94%    94%    94%    94%    94%    94%    94%    94%    96%    96%    96%    96%    96%    96%    96%    96%    98%    98%    98%    98%    98%    98%
  
  ffmpeg '-y' '-i' 'video/second_vid.mp4' '-filter_complex' '[0:v]drawtext=fontfile=/usr/share/fonts/truetype/msttcorefonts/arial.ttf:text='test text':fontcolor='ffffff@1':fontsize=30:x=(w-tw)/2:y=50:alpha='if(lt(t,2),0,if(lt(t,4),(t-2)/2,if(lt(t,24),1,if(lt(t,26),(2-(t-24))/2,0))))'' '-threads' '8' '-vcodec' 'libx264' '-acodec' 'aac' '-max_muxing_queue_size' '400' '-b:v' '1000k' '-refs' '6' '-coder' '1' '-sc_threshold' '40' '-flags' '+loop' '-me_range' '16' '-subq' '7' '-i_qfactor' '0.71' '-qcomp' '0.6' '-qdiff' '4' '-trellis' '1' '-b:a' '256k' '-ac' '2' '-pass' '1' '-passlogfile' '/tmp/ffmpeg-passes5b738244e22e0b38pp/pass-5b738244e2412' '/data/tmp/ffmpeg-ed6a389106090a6a9f9c71c7c357400b-5b738244e2215.mp4'
  
      2%    2%    4%    6%    8%    10%    12%    14%    14%    16%    18%    18%    20%    22%    22%    24%    26%    28%    30%    30%    32%    34%    34%    36%    38%    40%    42%    44%    44%    46%    48%
  
  ffmpeg '-y' '-i' 'video/second_vid.mp4' '-filter_complex' '[0:v]drawtext=fontfile=/usr/share/fonts/truetype/msttcorefonts/arial.ttf:text='test text':fontcolor='ffffff@1':fontsize=30:x=(w-tw)/2:y=50:alpha='if(lt(t,2),0,if(lt(t,4),(t-2)/2,if(lt(t,24),1,if(lt(t,26),(2-(t-24))/2,0))))'' '-threads' '8' '-vcodec' 'libx264' '-acodec' 'aac' '-max_muxing_queue_size' '400' '-b:v' '1000k' '-refs' '6' '-coder' '1' '-sc_threshold' '40' '-flags' '+loop' '-me_range' '16' '-subq' '7' '-i_qfactor' '0.71' '-qcomp' '0.6' '-qdiff' '4' '-trellis' '1' '-b:a' '256k' '-ac' '2' '-pass' '2' '-passlogfile' '/tmp/ffmpeg-passes5b738244e22e0b38pp/pass-5b738244e2412' '/data/tmp/ffmpeg-ed6a389106090a6a9f9c71c7c357400b-5b738244e2215.mp4'
  
      52%    52%    54%    54%    56%    56%    58%    58%    60%    60%    62%    64%    66%    68%    70%    70%    72%    74%    76%    76%    78%    80%    82%    84%    86%    86%    88%    88%    90%    90%    92%    94%    96%    98%
  
  ffmpeg '-y' '-f' 'concat' '-safe' '0' '-i' '/data/tmp/ffmpeg-concat-5b73814f9fe10' '-c' 'copy' 'video_out/done_vid.mp4'
  

  (For some reason it seems to run the encoding of each video command again at 50%)

  So when I play ffmpeg-ed6a389106090a6a9f9c71c7c357400b-5b738244e2215.mp4, the text is in there, but when I play the output file (done_vid.mp4), the text isn't there.

  What's going on?

  UPDATE: Here are the ffprobes of the 2 temp files in case they help:

  Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'data/tmp/ffmpeg-7a580007c010377da19305b0836e7a4d-5b73814f9ff35.mp4':
    Metadata:
      major_brand     : isom
      minor_version   : 512
      compatible_brands: isomiso2avc1mp41
      encoder         : Lavf57.83.100
    Duration: 00:02:25.17, start: 0.000000, bitrate: 1247 kb/s
      Stream #0:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 1280x720 [SAR 1:1 DAR 16:9], 999 kb/s, 23.98 fps, 23.98 tbr, 24k tbn, 47.95 tbc (default)
      Metadata:
        handler_name    : VideoHandler
      Stream #0:1(eng): Audio: aac (LC) (mp4a / 0x6134706D), 44100 Hz, stereo, fltp, 242 kb/s (default)
      Metadata:
        handler_name    : SoundHandler
  
  
  Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'data/tmp/ffmpeg-ed6a389106090a6a9f9c71c7c357400b-5b738244e2215.mp4':
    Metadata:
      major_brand     : isom
      minor_version   : 512
      compatible_brands: isomiso2avc1mp41
      encoder         : Lavf57.83.100
    Duration: 00:01:30.03, start: 0.000000, bitrate: 322 kb/s
      Stream #0:0(und): Video: h264 (High 4:4:4 Predictive) (avc1 / 0x31637661), yuv444p, 1280x720 [SAR 1:1 DAR 16:9], 61 kb/s, 23.98 fps, 23.98 tbr, 19184 tbn, 47.96 tbc (default)
      Metadata:
        handler_name    : VideoHandler
      Stream #0:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 44100 Hz, stereo, fltp, 258 kb/s (default)
      Metadata:
        handler_name    : SoundHandler
  

• Ubuntu push rtmp video and audio to v4l2loopback and snd-dummy devices

  15 août 2018, par Dangel

  I currently have a RTMP stream going on and I want to take that stream and push it to a v4l2loopback virtual camera and a snd-dummy sound device.

  I've created the virtual devices for video and audio using v4l2loopback and snd-dummy kernel modules.

  I've already managed to push the video to the virtual camera using:

  ffmpeg -i rtmp://192.168.x.x:xxxx/stream/stream_id -f v4l2 /dev/video10
  

  Now I need to do the same for the virtual microphone, tried adding this to the command but didn't work

  -f alsa hw:2
  

  Now it seems like it's pushing the audio to the device but I see no activity in alsamixer or volume control and can't find the audio device to use it for example as an audio source in OBS.

  How can I push the audio to the device and use it to stream to a flash page?

• mid-roll ads in HLS or mpeg-dash [on hold]

  15 août 2018, par evan

  I'm encoding my videos with ffmpeg and transcoding them into HLS videos. I want to add mid-roll ads to my converted videos.

  I was wondering what is the best way to do it? should I just add the ads to my video and make a big video stream and then do the HLS thing? or I should break the HLs video and put the ads in the middle while playing?

  My content is live streaming and I want to add mid-roll ads in the middle of my video while playing.

  ffmpeg -i main720.MTS -movflags faststart -s 640*360 -r 24 -vcodec libx264 -preset slow -tune zerolatency -tune fastdecode -b:v 300k -maxrate 300k -bufsize 400k -g 96 -an hls3/main720_300.mp4 -s 1280*720 -r 24 -vcodec libx264 -preset slow -tune zerolatency -tune fastdecode -b:v 700k -maxrate 700k -bufsize 1000k -g 96 -an hls3/main720_700.mp4 -hls_time 4 -hls_segment_filename 'hls3/file%03d.ts' -hls_list_size 0 hls3/out.m3u8
  

• Need to convert file format then merge audio files in ffmpeg using bat file

  14 août 2018, par Matthew

  I have been searching quite a bit and cannot find the pieces to make this work. I am looking to convert .g729 audio files to .wav then merge 2 files, and IN and an OUT, into 1 file. I have this much working already.

  @echo off 
  for %%A IN (*.g729) DO ffmpeg -i "%%A" "%%A.wav" done
  

  I have not been able to get the merge to work, I have the basic ffmpeg command to accomplish what I need but it isn't part of the loop.

  ffmpeg -i -in.wav -i -out.wav -filter_complex amerge -ac 2 -c:a libmp3lame -q:a 4 output.wav
  

  Any input to get both into one batch would be very helpful.

• How to reduce GIF file size with ffmpeg ?

  14 août 2018, par tvt tvt

  we use all command but not work properlly. how to reduce GIF file size convert mb to kb with ffmpeg commands?