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• Decoding h.264 in node.js without ffmpeg and send it to front or save it in fs

  5 mars 2019, par JT.v26

  I’m doing the final project of a bootcamp.

  The project consists of controlling a drone (Tello) with a mobile phone. So for this project I’m using react native. In which I insert a node.js inside the application (Node.js for Mobile Apps React Native) since the drone creates a wifi and I lose internet access to connect to a remote server.

  All right so far, the drone has three udp ports enabled on the sdk to receive instructions, send status and send video.
  The video gives it to me in raw.

  I did a test on the computer, downloading ffmpeg and converting that data and I could effectively have the video retransmission.

  My questions are :

  Is there any way I can use the same technique on the mobile without needing ffmpeg ?

  Is there any way to import ffmpeg into android and communicate with nodejs ?

  Is there any other solution where I can use another node that doesn’t have to be on the phone ?

  Or you may even find some other solution to address this problem.

  Thank you very much in advance

• 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.

  


• ffmpeg convert from WMV to AVC1 instead of "official" H264 [closed]

  26 mars 2014, par thipeto

  I searched google for an answer, but I can’t find the solution. It’s for professional use.

  I’m trying to convert some wmv files (WMV3) to MP4 (H.264). It should take the format h.264, and instead of it, it’s taken the H.264 (AVC1) format.

  It seems like the AVC is a format used in Apple, and I don’t want to convert to this format, only to h264 "official", the one who fourcc shows me.
  I’m using the last version of ffmpeg, following is the basic command that I’m using :

  ffmpeg -i input.wmv -c:v libx264 -q:v 0 output.mp4

  I’m trying to understand the reason that some PCs here convert to h264, and other to AVC1.
  Someone can help me ? What should I do to make the other PCs convert to the real h.264 without install a pack of codecs ? I just want to convert to mp4, there’s a way to install only codecs to convert to mp4 ?

  Many thanks,
  Thiago.