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• Revision 3276 : Un bouton de déconnexion dans le menu du haut

  19 avril 2010, par kent1 — Log

  Un bouton de déconnexion dans le menu du haut

• Cloud Functions for Firebase : completing long processes without touching maximum timeout

  17 février, par Scott Ewing

  I have to transcode videos from webm to mp4 when they're uploaded to firebase storage. I have a code demo here that works, but if the uploaded video is too large, firebase functions will time out on me before the conversion is finished. I know it's possible to increase the timeout limit for the function, but that seems messy, since I can't ever confirm the process will take less time than the timeout limit.

  



  Is there some way to stop firebase from timing out without just increasing the maximum timeout limit ?

  



  If not, is there a way to complete time consuming processes (like video conversion) while still having each process start using firebase function triggers ?

  



  If even completing time consuming processes using firebase functions isn't something that really exists, is there some way to speed up the conversion of fluent-ffmpeg without touching the quality that much ? (I realize this part is a lot to ask. I plan on lowering the quality if I absolutely have to, as the reason webms are being converted to mp4 is for IOS devices)

  



  For reference, here's the main portion of the demo I mentioned. As I said before, the full code can be seen here, but this section of the code copied over is the part that creates the Promise that makes sure the transcoding finishes. The full code is only 70 something lines, so it should be relatively easy to go through if needed.

  



  const functions = require('firebase-functions');
const mkdirp = require('mkdirp-promise');
const gcs = require('@google-cloud/storage')();
const Promise = require('bluebird');
const ffmpeg = require('fluent-ffmpeg');
const ffmpeg_static = require('ffmpeg-static');


  



  (There's a bunch of text parsing code here, followed by this next chunk of code inside an onChange event)

  



  function promisifyCommand (command) {
    return new Promise( (cb) => {
        command
        .on( 'end',   ()      => { cb(null)  } )
        .on( 'error', (error) => { cb(error) } )
        .run();
    })
}
return mkdirp(tempLocalDir).then(() => {
    console.log('Directory Created')
    //Download item from bucket
    const bucket = gcs.bucket(object.bucket);
    return bucket.file(filePath).download({destination: tempLocalFile}).then(() => {
      console.log('file downloaded to convert. Location:', tempLocalFile)
      cmd = ffmpeg({source:tempLocalFile})
               .setFfmpegPath(ffmpeg_static.path)
               .inputFormat(fileExtension)
               .output(tempLocalMP4File)
      cmd = promisifyCommand(cmd)
      return cmd.then(() => {
        //Getting here takes forever, because video transcoding takes forever!
        console.log('mp4 created at ', tempLocalMP4File)
        return bucket.upload(tempLocalMP4File, {
            destination: MP4FilePath
        }).then(() => {
          console.log('mp4 uploaded at', filePath);
        });
      })
    });
  });


  


• How can I use variables in long PowerShell command without breaking the command

  15 octobre 2020, par AFouquet

  I want to use ffmpeg to convert .m4a files in to .mp3 files.

  


  I can do it for each single file, but that takes a lot of effort to type in.

  


  ffmpeg -i '.\song.m4a' -ac 2 -b:a 192k '.\song.mp3'


  


  Is there a way to do this with powershell using variables ?
ex :

  


  ffmpeg -i $v -ac 2 -b:a 192k $v.mp3


  


  The problem with this is that then the -ac flag is taken as part of the path and not of ffmpeg anymore.

  


  Is there a way around this in powershell ?
  
Or could this be done with an array ? If I use $v=Get-ChildItem -Name and iterate over the array with a foreach loop in to the ffmpeg command.

  


  I am very new to PowerShell and don't have a lot of experience but it seems to me that should be possible to do.

  


  I would appreciate any help I can get.