Recherche avancée

Sur d’autres sites (10475)

• Make gif (ffmpeg) using MOST RECENT 7 jpg files in a directory

  16 juillet 2019, par Brad Sullivan

  I have a bash script which runs on a cron, to take screenshots of my cctv 1x per day to do an annual timelapse. It all works, and I get a YTD sofar.gif of the very first screenshot to the very last screenshot — which is now quite long. I wanted to add a line to make last7days.gif so I could get a shorter weekly gif etc.

  I have searched this site and the web and can list the newest 7 files in terminal using : ls -1t | head -n 9 | tail -n 7 (this removes the .gif and .mov which are modified last) but I do not know how to make that vertical list of 7 filenames into a variable to make a gif using those file names

  # runs from a cronjob. saves live screenshot from CCTV to jpg, then updates the year-to-date movie
  
  
  
  if [ $# -ne 1 ]
  
  then
  
    echo "Usage: `basename $0` OUTDIR"
  
    exit 65
  
  fi
  
  
  
  doexit=0
  
  
  
  start=$(date +%s)
  
  end=$(date +%s)
  
  
  
  outdir=${1%/}
  
  mkdir $outdir
  
  echo "Capturing image..."
  
  
  
  counter=$(date +"%Y_%m_%d_%H-%M-%S");
  
  file=$outdir/$counter.jpg
  
  
  
  if response=$(curl --silent --write-out %{http_code} --max-time 600 'URL REDACTED' -o $file) ; then
  
      echo "Captured & saved $file!"
  
  else
  
      echo "Failed to capture $file"
  
  fi
  
  
  
  ffmpeg -hide_banner -loglevel panic -pattern_type glob -i $outdir/'*.jpg' $outdir/sofar.mov -y
  
  ffmpeg -hide_banner -loglevel panic -pattern_type glob -i $outdir/'*.jpg' $outdir/sofar.gif -y
  
  
  
  exit 1

  Currently, the last lines create a .gif using every image file, this works only because they are saved with the date in the filename.

  I want to add a line to create a .gif using just the most 7 recent images

• not able to convert a specific .wav file to mp3 or m4a with sox, avconv

  25 juillet 2017, par astrograph

  At the office we have a project where we apply IoT technologies to a real bee hive.

  One of the features is to detect specific sounds the bees make when a new queen hatches. We have a special microphone in place, the algorithm is also implemented. For now we get a lot of false positives, and want to quickly be able to identify them, by listening to the audio files in the browser. Therefore I want to convert the .wav files to either .mp3 or .m4a

  The .wav file format seems to be quite strange, as I was not able to convert it to mp3 using avconv, sox or even audacity. The funny thing is, the Microsoft media player can play the .wav file fine.

  Here is the information soxi gives about the wav file :

  pi@raspberrypi:~ $ soxi Channel1.wav
  
  soxi WARN wav: wave header missing extended part of fmt chunk
  
  
  
  Input File     : 'Channel1.wav'
  
  Channels       : 1
  
  Sample Rate    : 6250
  
  Precision      : 24-bit
  
  Duration       : 00:01:21.00 = 506250 samples ~ 6075 CDDA sectors
  
  File Size      : 2.03M
  
  Bit Rate       : 200k
  
  Sample Encoding: 32-bit Floating Point PCM

  This is the avconv command I am trying to use :

  avconv -y -v quiet -i Channel1.wav -strict experimental -ar 44100 -ab 160k Channel1.m4a

  I also tried with sox :

  sox  -v 0.60 Channel1.wav -r 22050 Channel1.m4a

  but the output is mostly silent, with some random noise.

  The question is how can a wav file like this : https://drive.google.com/open?id=0B9YVh-jkOMLsQThERlI2emN2QWM be converted to an audio format using a raspberry pi that can be played in the browser ?

• How to convert a Stream on the fly with FFMpegCore ?

  18 octobre 2023, par Adrian

  For a school project, I need to stream videos that I get from torrents while they are downloading on the server.
When the video is a .mp4 file, there's no problem, but I must also be able to stream .mkv files, and for that I need to convert them into .mp4 before sending them to the client, and I can't find a way to convert my Stream that I get from MonoTorrents with FFMpegCore into a Stream that I can send to my client.

  


  Here is the code I wrote to simply download and stream my torrent :

  


  var cEngine = new ClientEngine();

var manager = await cEngine.AddStreamingAsync(GenerateMagnet(torrent), ) ?? throw new Exception("An error occurred while creating the torrent manager");

await manager.StartAsync();
await manager.WaitForMetadataAsync();

var videoFile = manager.Files.OrderByDescending(f => f.Length).FirstOrDefault();
if (videoFile == null)
    return Results.NotFound();

var stream = await manager.StreamProvider!.CreateStreamAsync(videoFile, true);
return Results.File(stream, contentType: "video/mp4", fileDownloadName: manager.Name, enableRangeProcessing: true);


  


  I saw that the most common way to convert videos is by using ffmpeg. .NET has a package called FFMpefCore that is a wrapper for ffmpeg.

  


  To my previous code, I would add right before the return :

  


  if (!videoFile.Path.EndsWith(".mp4"))
{
    var outputStream = new MemoryStream();
    FFMpegArguments
        .FromPipeInput(new StreamPipeSource(stream), options =>
        {
            options.ForceFormat("mp4");
        })
        .OutputToPipe(new StreamPipeSink(outputStream))
        .ProcessAsynchronously();
    return Results.File(outputStream, contentType: "video/mp4", fileDownloadName: manager.Name, enableRangeProcessing: true);
}


  


  I unfortunately can't get a "live" Stream to send to my client.