Recherche avancée

Sur d’autres sites (5268)

• Create mp4 file from raw h264 using a pipe instead of files

  16 avril 2019, par Charlie Burns

  I have a raw h264 file that I can display with VLC, on a mac :

  open -a VLC file.h264

  I can convert this to mp4 with the command line

  ffmpeg -f h264 -i file.h264 -c:v copy file.mp4

  But what I really want to do is something like :

  cat file.h264 | ffmpeg > file.mp4

  Reason being that the input is coming over a socket and I want to convert it and send it to a video tag in an html file on the fly.

  An alternative solution would be a way to display the raw h264 in a web page without converting it to mp4 first.

  The input is coming in frame by frame, the first four bytes are 0,0,0,1. My understanding is that this h264 Annex B format.

  I know nothing about video formats, I would grateful to be pointed in a direction to look.

  Should I look into writing code using libavcodec like this quuesion or is there an off-the-shelf solution ?

  H.264 muxed to MP4 using libavformat not playing back

  Thanks !

• How to play a specific number of samples from an audio file using ffmpeg ?

  2 juillet 2023, par FrostDream

  I'm trying to use ffmpeg in a command-line or terminal environment to play only a specific number of samples from an audio file. Instead of playing the entire audio, I want to extract and play a precise portion based on the sample count.

  


  I came across the following example command that seems to be relevant :

  


  ffmpeg -ss 0 -t [SAMPLE_COUNT] -i [INPUT_AUDIO_FILE] -f wav - | ffplay -


  


  In the command, I understand that -ss is used to specify the start time as 0, -t sets the duration as the sample count, -i defines the input audio file, and -f sets the output format as WAV. The output is then piped to ffplay, a simple media player provided with ffmpeg, which will play the specified number of samples from the audio file.

  


  However, I'm not entirely sure about the usage and options of ffmpeg in this scenario. Could someone please provide a detailed explanation of how to correctly use ffmpeg to achieve this ? Any additional insights, tips, or alternative approaches would also be greatly appreciated. Thank you !

  


• What are the different ways to generate thumbnail of video in PHP ? [on hold]

  10 février 2016, par Vaidehi

  Is there any alternative for FFMPEG to get Video thumbnails in PHP ?
  Client don’t want to use EXEC and other server commands due to security issues.
  FFMPEG library need EXEC() to be enabled. So I am looking for other alternatives.
  I am using below code to generate thumbnail of video using PHP. But on server exec() function is disabled due to security reasons. So, I can’t use FFMPEG to generate thumbnail.

  ----------------------------
  
  $thumbnail_path = "your_site_domain/media/images/thumbnail/"; 
  
  $second = 1;
  
  $thumbSize="150x150"; 
  
  $videoname="sample_video";
  
  
  
  $cmd="{$ffmpeg_installation_path} -i {$video_file_path} -deinterlace -an -ss {$second} -t 00:00:01  -s {$thumbSize} -r 1 -y -vcodec mjpeg -f mjpeg {$path_to_store_generated_thumbnail} 2>&1";
  
  exec($cmd, $output, $retval);
  
  if ($retval)
  
  {
  
      echo "error in generating video thumbnail";
  
  }
  
  else
  
  {
  
      echo "Thumbnail generated successfully";
  
      echo $thumb_path=$thumbnail_path.$videoname.".jpg";
  
  }
  
  -------------------------------

  In my case, video can be of any format like .mp4, .avi, youtube link or any possible video which I am going to upload using php and while uploading I want to generate thumbnail of same. If any solution then please reply me back.