Recherche avancée

Sur d’autres sites (10067)

• ffmpeg php video basic uses and types

  15 mai 2014, par HackerManiac

  Can anyone give a code on how do i covert a video using ffmpeg.

  As thought currently i have only uploading system.

  vu.php(only a part is shown)

  define('UPLOAD','../../videos/');
  
      $fileName = time().$file['name']; 
  
      $target = UPLOAD.$fileName;
  
  
  
    if(move_uploaded_file($file['tmp_name'],$target)){                
  
        exec("ffmpeg -i ".UPLOAD." ".UPLOAD.$filename.".flv"); 
  
    }

  This pice of code block just uploads the video on video folder but does not converts it to .flv.
  I am not sure how to use ffmpeg.

  My diretory looks like this

  www[localhost]->videos[videos folder]
  
  www[localhost]->pictures[pictures folder]
  
  www[localhost]->resources[folder]->php[folder]->vu.php

  I also want to return a .jpg image of any frame of video through json by converting via ffmpeg and uploading it to pictures folder.

  return json_encode(array("thumbnail"=>$image_src));

  UPDATE 1

  The above stuff was solved but now i have a question regarding video conversion.
  Suppose i have a file.avi and i want to convert it in 3 sizes of .flv format -> Low(320p) ,Medium (720p)and HD(1080p)

  what commands will i have to send to shell_exec(); and will that be fast enough ?
  CUrrently what i have is

  $vidSize = "640x480";
  
  $ffmpeg -i $videoFile -ar 22050 -ab 32 -f flv -s $vidSize $vidFile

  And i am not sure what -ar and -ab means and what value will be good for all those 3 sized videos ?

• Basic FFmpeg Conversion Error ?

  26 mars 2018, par Sarah Szabo

  I’m trying to convert an .mp4 to a .opus file using ffmpeg. I have a directory on my desktop called Indexing which has a test file called 40.mp4. I’ve tried using the command ffmpeg -i 40.mp4 -b:a 320k 40.opus which always works from a terminal set in the Indexing directory, but trying the same thing using Java always fails :

  NOTE : I’m running on Kubuntu 17.10

  private static final Path INDEXING_PATH = Paths.get("/home/sarah/Desktop/Indexing");

  Process proc = new ProcessBuilder("ffmpeg -i 40.mp4 -b:a 320k 40.opus")
                 .directory(INDEXING_PATH.toFile()).inheritIO().start();

  Yields :

  Exception in thread "main" java.io.IOException: Cannot run program "ffmpeg -i 40.mp4 -b:a 320k 40.opus" (in directory "/home/sarah/Desktop/Indexing"): error=2, No such file or directory
     at java.lang.ProcessBuilder.start(ProcessBuilder.java:1048)

  Here’s a snapshot of the folder :
  

• FFMPEG Concat Demuxer adds more time to video than expected

  5 septembre 2023, par Shreyas

  I am using ffmpeg concat demuxer to join multiple(189) videos together.
The videos are originally split from a single video using the following command :

  


  ffmpeg -ss time[2] -vsync 1 -copyts -i inputfile.mp4 -ss time[0] -to time[1] -c:a copy -c:v libx264 -b:v 800k output.mp4


  


  Thereafter I am using the following concat command :

  


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


  


  The problem is that the sum of the lengths of the input videos is 24:03:520
The output.mp4 video comes out to be 24:05:550.
Which is two seconds longer than the constituent video length.

  


  I need the output video to be time accurate. How can I achieve this without reencoding the video ?