Recherche avancée

Sur d’autres sites (4452)

• `ffmpet -f concat` don't work when all input streams appear to have the same spec

  9 mars 2023, par Roy

  My ffmpeg command :

  


  ffmpeg -safe 0 -f concat -i list.txt -c copy out.mp4


  


  My 1st input file :

  


  Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'D:\Applications\ffmpeg_6.0_full\a.mp4':
  Metadata:
    major_brand     : isom
    minor_version   : 512
    compatible_brands: isomiso2avc1mp41
    encoder         : Lavf60.3.100
  Duration: 00:00:04.97, start: 0.000000, bitrate: 40 kb/s
  Stream #0:0[0x1](und): Audio: aac (LC) (mp4a / 0x6134706D), 44100 Hz, stereo, fltp, 2 kb/s (default)
    Metadata:
      handler_name    : SoundHandler
      vendor_id       : [0][0][0][0]
  Stream #0:1[0x2](und): Video: h264 (Main) (avc1 / 0x31637661), yuv420p(tv, progressive), 1920x1080 [SAR 1:1 DAR 16:9], 27 kb/s, 30 fps, 30 tbr, 30k tbn (default)
    Metadata:
      handler_name    : VideoHandler
      vendor_id       : [0][0][0][0]
      encoder         : Lavc60.3.100 libx264


  


  My 2nd input file :

  


  Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'D:\Applications\ffmpeg_6.0_full\b.mp4':
  Metadata:
    major_brand     : mp42
    minor_version   : 0
    compatible_brands: mp41isom
    creation_time   : 2023-03-08T06:47:13.000000Z
    artist          : Microsoft Game DVR
    title           : PUBG: BATTLEGROUNDS
  Duration: 00:10:00.16, start: 0.000000, bitrate: 20885 kb/s
  Stream #0:0[0x1](und): Video: h264 (Main) (avc1 / 0x31637661), yuv420p(tv, progressive), 1920x1080 [SAR 1:1 DAR 16:9], 20739 kb/s, 30 fps, 30 tbr, 30k tbn (default)
    Metadata:
      creation_time   : 2023-03-08T06:47:13.000000Z
      handler_name    : VideoHandler
      vendor_id       : [0][0][0][0]
      encoder         : AVC Coding
  Stream #0:1[0x2](und): Audio: aac (LC) (mp4a / 0x6134706D), 44100 Hz, stereo, fltp, 131 kb/s (default)
    Metadata:
      creation_time   : 2023-03-08T06:47:13.000000Z
      handler_name    : SoundHandler
      vendor_id       : [0][0][0][0]


  


  The above command outputs some warning signals :

  


  [mov,mp4,m4a,3gp,3g2,mj2 @ 0000025239902d40] Auto-inserting h264_mp4toannexb bitstream filter
[mp4 @ 00000252396fe5c0] Non-monotonous DTS in output stream 0:1; previous: 218112, current: 150024; changing to 218113. This may result in incorrect timestamps in the output file.
...
a lot of them
...
frame=25992 fps=21754 q=-1.0 Lsize= 1519621kB time=00:14:49.39 bitrate=13996.8kbits/s speed= 744x
video:9649kB audio:1519216kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: unknown


  


  The resultant video can play the first part of the video correctly, then the video players either skips directly to the end of the video (MPC-HC), or don't render anything at all while timer passes as normal (VLC).

  


  My impression of the concat is that it requires all videos to have the same spec, which I think my input achieved (all the "Steam #0:0", etc, line matches). I only see the following difference, which I assumed that should be okay :

  


  

  1. Metadata are different both for the whole input (e.g. "major_brand") and for each stream (e.g. "encoder"). I assumed that metadata won't affect the processing.

  


  2. The order of video/audio streams are different in the two inputs : the 1st input file has audio then video ; the 2nd input file has video then audio. I assumed that ffmpeg knows the difference and won't concat a video stream to an audio stream.

  


  


  The full output of the command can be found in this pastebin : https://pastebin.com/Z5q97Uyg

  


• `ffmpeg -f concat` don't work when all input streams appear to have the same spec

  2 octobre 2024, par Roy

  My ffmpeg command :

  


  ffmpeg -safe 0 -f concat -i list.txt -c copy out.mp4


  


  My 1st input file :

  


  Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'D:\Applications\ffmpeg_6.0_full\a.mp4':
  Metadata:
    major_brand     : isom
    minor_version   : 512
    compatible_brands: isomiso2avc1mp41
    encoder         : Lavf60.3.100
  Duration: 00:00:04.97, start: 0.000000, bitrate: 40 kb/s
  Stream #0:0[0x1](und): Audio: aac (LC) (mp4a / 0x6134706D), 44100 Hz, stereo, fltp, 2 kb/s (default)
    Metadata:
      handler_name    : SoundHandler
      vendor_id       : [0][0][0][0]
  Stream #0:1[0x2](und): Video: h264 (Main) (avc1 / 0x31637661), yuv420p(tv, progressive), 1920x1080 [SAR 1:1 DAR 16:9], 27 kb/s, 30 fps, 30 tbr, 30k tbn (default)
    Metadata:
      handler_name    : VideoHandler
      vendor_id       : [0][0][0][0]
      encoder         : Lavc60.3.100 libx264


  


  My 2nd input file :

  


  Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'D:\Applications\ffmpeg_6.0_full\b.mp4':
  Metadata:
    major_brand     : mp42
    minor_version   : 0
    compatible_brands: mp41isom
    creation_time   : 2023-03-08T06:47:13.000000Z
    artist          : Microsoft Game DVR
    title           : PUBG: BATTLEGROUNDS
  Duration: 00:10:00.16, start: 0.000000, bitrate: 20885 kb/s
  Stream #0:0[0x1](und): Video: h264 (Main) (avc1 / 0x31637661), yuv420p(tv, progressive), 1920x1080 [SAR 1:1 DAR 16:9], 20739 kb/s, 30 fps, 30 tbr, 30k tbn (default)
    Metadata:
      creation_time   : 2023-03-08T06:47:13.000000Z
      handler_name    : VideoHandler
      vendor_id       : [0][0][0][0]
      encoder         : AVC Coding
  Stream #0:1[0x2](und): Audio: aac (LC) (mp4a / 0x6134706D), 44100 Hz, stereo, fltp, 131 kb/s (default)
    Metadata:
      creation_time   : 2023-03-08T06:47:13.000000Z
      handler_name    : SoundHandler
      vendor_id       : [0][0][0][0]


  


  The above command outputs some warning signals :

  


  [mov,mp4,m4a,3gp,3g2,mj2 @ 0000025239902d40] Auto-inserting h264_mp4toannexb bitstream filter
[mp4 @ 00000252396fe5c0] Non-monotonous DTS in output stream 0:1; previous: 218112, current: 150024; changing to 218113. This may result in incorrect timestamps in the output file.
...
a lot of them
...
frame=25992 fps=21754 q=-1.0 Lsize= 1519621kB time=00:14:49.39 bitrate=13996.8kbits/s speed= 744x
video:9649kB audio:1519216kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: unknown


  


  The resultant video can play the first part of the video correctly, then the video players either skips directly to the end of the video (MPC-HC), or don't render anything at all while timer passes as normal (VLC).

  


  My impression of the concat is that it requires all videos to have the same spec, which I think my input achieved (all the "Steam #0:0", etc, line matches). I only see the following difference, which I assumed that should be okay :

  


  

  1. Metadata are different both for the whole input (e.g. "major_brand") and for each stream (e.g. "encoder"). I assumed that metadata won't affect the processing.

  


  2. The order of video/audio streams are different in the two inputs : the 1st input file has audio then video ; the 2nd input file has video then audio. I assumed that ffmpeg knows the difference and won't concat a video stream to an audio stream.

  


  


  The full output of the command can be found in this pastebin : https://pastebin.com/Z5q97Uyg

  


• ffmpeg 180 degree panoramic fisheye image to equirectangular / flat

  7 juillet 2024, par Willy62

  I am trying to get my Hikvision Panovu image of a sportsfield to look like a standard camera image, similar to what would be seen with a Veo solution / traditional camera.

  


  This is what the image would ideally look like with a little bit of zoom. Note the players are all upright and it looks "correct" and not skewed with the far end of the field in line with the horizon.

  


  veo sample image

  


  The original image looks like this (same field but other side). This is a 180 degree panoramic image from a Hikvision camera as found here.

  


  It provides the following output natively.

  


  hikvision native view

  


  I have had some luck converting the image with ffmpeg using the v360 filter. Note there is a downward tilt meaning I have to apply some yaw to correct it.

  


  v360=input=fisheye:output=rectilinear:ih_fov=180:iv_fov=87.5:d_fov=87.5:pitch=20:yaw=5:w=3840:h=2160


  


  And this gets the following output :

  


  deskewed v360 image

  


  So the challenge here to make the original image flat/equirect but to address the skew such that :

  


  

  • the players are orientated "upright"

  


  • the far sideline of the field looks like a straight line in line with the horizon

  


  • the image quality is preserved as best as possible

  


  


  With these cameras the image is 32MP so there is the opportunity to do an ePTZ into the area of interest.

  


  I suspect v360 isnt the right choice here and it is some remap-style filter, or perhaps I am best going across to gstreamer or similar.

  


  I tried an ffmpeg v360 filter and it partially works, but the players are still skewed because the top of the image is not wide enough. The issue can possibly be solved by correctly applying a couplex perspective filter, but I think this will only mask the issue and perspective requires a complex filter that hasn't worked for me so far.