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Autres articles (111)
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Le profil des utilisateurs
12 avril 2011, parChaque utilisateur dispose d’une page de profil lui permettant de modifier ses informations personnelle. Dans le menu de haut de page par défaut, un élément de menu est automatiquement créé à l’initialisation de MediaSPIP, visible uniquement si le visiteur est identifié sur le site.
L’utilisateur a accès à la modification de profil depuis sa page auteur, un lien dans la navigation "Modifier votre profil" est (...) -
Configurer la prise en compte des langues
15 novembre 2010, parAccéder à la configuration et ajouter des langues prises en compte
Afin de configurer la prise en compte de nouvelles langues, il est nécessaire de se rendre dans la partie "Administrer" du site.
De là, dans le menu de navigation, vous pouvez accéder à une partie "Gestion des langues" permettant d’activer la prise en compte de nouvelles langues.
Chaque nouvelle langue ajoutée reste désactivable tant qu’aucun objet n’est créé dans cette langue. Dans ce cas, elle devient grisée dans la configuration et (...) -
XMP PHP
13 mai 2011, parDixit Wikipedia, XMP signifie :
Extensible Metadata Platform ou XMP est un format de métadonnées basé sur XML utilisé dans les applications PDF, de photographie et de graphisme. Il a été lancé par Adobe Systems en avril 2001 en étant intégré à la version 5.0 d’Adobe Acrobat.
Étant basé sur XML, il gère un ensemble de tags dynamiques pour l’utilisation dans le cadre du Web sémantique.
XMP permet d’enregistrer sous forme d’un document XML des informations relatives à un fichier : titre, auteur, historique (...)
Sur d’autres sites (9816)
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Decode audio using ffmpeg (packet-by-packet) in Java
27 mai 2022, par quad478In my application, I receive an audio stream from an IP-camera via RTP using NETTY.
The stream from IP-camera comes in the "G.711 mulaw" format, I would like to recode it to the "AAC" format.
I can't use files in this task as it's a live stream, and each packet needs to be decoded and delivered to the client (browser) immediately.
For this task, I wanted to use the ffmpeg child process :
when connecting to the camera, create a ffmpeg process and send to stdin (ffmpeg) each received packet, then I would like to receive the decoded packet from stdout.
Here is the command I run ffmeg with :


"ffmpeg.exe -f mulaw -re -i - -f adts -"


I'm not sure if "-re" should be used here, but without this option, ffmpeg outputs the decode result only after stdin is closed and the process exits.
The problem is that I don't get anything on stdout after sending the packet to ffmpeg.


Decoder code :


package ru.ngslab.insentry.web.video.protocols.rtp;

import io.netty.buffer.ByteBuf;
import io.netty.channel.ChannelHandlerContext;
import io.netty.handler.codec.MessageToMessageDecoder;

import java.io.Closeable;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.List;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.Future;

public class RtpFfmpegDecoder extends MessageToMessageDecoder<rtppacket> implements Closeable {

 private final Process ffmegProcess;
 private final OutputStream ffmpegOutput;
 private final InputStream ffmegInput;
 private final ExecutorService ffmpegInputReaderService = Executors.newSingleThreadExecutor();

 public RtpFfmpegDecoder() {

 //Start Ffmpeg process
 ProcessBuilder ffmpegBuilder = new ProcessBuilder("ffmpeg.exe", "-f", "mulaw",
 "-re", "-i", "-", "-f", "adts", "-").redirectError(ProcessBuilder.Redirect.INHERIT);
 try {
 ffmegProcess = ffmpegBuilder.start();
 ffmpegOutput = ffmegProcess.getOutputStream();
 ffmegInput = ffmegProcess.getInputStream();
 } catch (IOException e) {
 throw new IllegalStateException(e);
 }
 }

 @Override
 protected void decode(ChannelHandlerContext channelHandlerContext, RtpPacket rtpPacket, List list) throws Exception {

 //start read ffmpeg output in another thread
 Future future = ffmpegInputReaderService.submit(this::startReadFFmpegOutput);

 //write rtp- packet bytes to ffmpeg-input
 ByteBuf data = rtpPacket.getData();
 byte[] rtpData = new byte[data.readableBytes()];
 data.getBytes(data.readerIndex(), rtpData);
 ffmpegOutput.write(rtpData);
 ffmpegOutput.flush();

 //waiting here for the decoding result from ffmpeg
 //blocks here
 byte[] result = future.get();
 //then process result...
 }

 private byte[] startReadFFmpegOutput() {
 try {
 //I don't know how many bytes to expect here, for test purposes I use 1024
 var bytes = new byte[1024];
 ffmegInput.read(bytes);
 return bytes;
 } catch (IOException e) {
 throw new IllegalStateException(e);
 }
 }

 @Override
 public void close() throws IOException {
 //Close streams code...
 }
}
</rtppacket>

This doesn't work because ffmpeg doesn't send anything after receiving the packet.
No errors in log, no output data.
Just wait for result here :


byte[] result = future.get();


Normally, ffmpeg only outputs after stdin is closed and the process stops.
It may be necessary to run ffmpeg with some special
parameters so that it outputs each received packet at once ?


I would be very grateful for any help


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Android FFMPEG : images to mp4 video converting
19 juillet 2017, par Giorgi AsaturyanI have tried many possible command line options with ffmpeg, however not getting this to work. Heres is my command file generator method :
private String[] generateCommandFile() {
ArrayList<string> cmd = new ArrayList<>();
cmd.add("-y");
cmd.add("-f");
cmd.add("concat");
cmd.add("-safe");
cmd.add("0");
cmd.add("-i");
String picturesTextFile = generateMergingFilesTexts();
if (picturesTextFile == null) {
return null;
}
cmd.add(picturesTextFile);
cmd.add("-i");
String audioTextFile;
if (numberOfAudioFiles > 1) {
audioTextFile = generateAudioFilesTexts();
} else {
audioTextFile = getAudioFilePath(audioRecordingFileName + Integer.toString(1));
}
cmd.add(audioTextFile);
cmd.add("-vsync");
cmd.add("vfr");
cmd.add("-pix_fmt");
cmd.add("yuv420p");
String currentDateTimeString = new SimpleDateFormat("dd MMMM yyyy", Locale.US).format(Calendar.getInstance().getTime());
File dirOut = new File(this.getExternalFilesDir(null), "D:T:" + currentDateTimeString);
if (!dirOut.exists()) {
dirOut.mkdirs();
}
directoryPath = dirOut.getAbsolutePath();
File fileOut = new File(dirOut, "T__" + Long.toString(totalTime) + "__P__" + Integer.toString(picturesModelInfo.getNumberOfShots()) + ".mp4");
cmd.add(fileOut.getAbsolutePath());
Log.d(TAG, "Saving File At " + fileOut.getAbsolutePath());
String[] finalCommand = new String[cmd.size()];
for (int i = 0; i < cmd.size(); i++) {
finalCommand[i] = cmd.get(i);
}
String finalString = "";
for (String command : finalCommand) {
finalString += command;
}
Log.d(TAG, "Final Command Is " + finalString);
return finalCommand;
}
</string>and here is my Final Command
-y-fconcat-safe0-i/storage/emulated/0/Android/data/com.essentialsln.memtalk/files/pictures_merging.txt-i/storage/emulated/0/Android/data/com.essentialsln.memtalk/files/AudioRecording1.3gp-vsyncvfr-pix_fmtyuv420p/storage/emulated/0/Android/data/com.essentialsln.memtalk/files/D:T:19 July 2017/T__2__P__3.mp4The main problem is that video not playing in android default player - displays ("Cannot Play video, unsupported file type"), but it works with VLC program. ))
Anu Suggestions ?
Thanks
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Repeat/loop the video till audio file using ffmpeg
18 mars 2014, par M. Usman AfzalI am using this command to generate the video from silent video and audio but the problem is video is 3 sec and audio is 20 sec and final video generating is 20 sec but video is for 3 sec and the last frame of that video is repeat till end.
ffmpeg -i v.mp4 -i a.m4a -c:v copy -c:a aac -strict experimental -map 0:v:0 -map 1:a:0 output.mp4I just want to repeat the whole video
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