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  • Emballe médias : à quoi cela sert ?

    4 février 2011, par

    Ce plugin vise à gérer des sites de mise en ligne de documents de tous types.
    Il crée des "médias", à savoir : un "média" est un article au sens SPIP créé automatiquement lors du téléversement d’un document qu’il soit audio, vidéo, image ou textuel ; un seul document ne peut être lié à un article dit "média" ;

Sur d’autres sites (1509)

  • C++ Realtime OpenGL videogame streaming library

    23 août 2013, par Mufasa

    I need to select a video encoder and library to take raw RGB frames in realtime from a videogame and send them to a remote client. The remote client is sending back mouse events. Right now I have a setup where the server is using glReadPixels to read frame data, then sending information in the form of 16x16 tiles with runlength encoding that have changed since the last read. (The videogame has a lot of solid color areas). My client works to control the game. But the transmission of frames to the client, and mouse events from the client, is too slow. Both use a TCP socket to communicate.

    I'm looking into using ffmpeg or x264 to encode into H.264 video ; do you think this could reduce latency ? I'm on windows and I can't figure out how to set up x264 libraries in Visual Studio, but I have got ffmpeg libraries installed.

    Another name I have heard is live555 but I don't know much about that.

    Do you have any recommendations ?

  • Jitsi and ffplay

    15 juin 2014, par Kotkot

    I’m playing with jitsi. Got examples form source code. I modified it a bit.
    Here is what I’ve got.
    I am trying to play the transmitted stream in VLC of ffplay or any other player,
    but I cannot.

    I use these application parameters to run the code :

    --local-port-base=5000 --remote-host=localhost --remote-port-base=10000

    What am I doing wrong ?

    package com.company;


       /*
        * Jitsi, the OpenSource Java VoIP and Instant Messaging client.
        *
    * Distributable under LGPL license.
    * See terms of license at gnu.org.
    */

    import org.jitsi.service.libjitsi.LibJitsi;
    import org.jitsi.service.neomedia.*;
    import org.jitsi.service.neomedia.device.MediaDevice;
    import org.jitsi.service.neomedia.format.MediaFormat;
    import org.jitsi.service.neomedia.format.MediaFormatFactory;

    import java.io.PrintStream;
    import java.net.DatagramSocket;
    import java.net.InetAddress;
    import java.net.InetSocketAddress;
    import java.util.HashMap;
    import java.util.Map;

    /**
    * Implements an example application in the fashion of JMF's AVTransmit2 example
    * which demonstrates the use of the <tt>libjitsi</tt> library for the purposes
    * of transmitting audio and video via RTP means.
    *
    * @author Lyubomir Marinov
    */
    public class VideoTransmitter {
       /**
        * The port which is the source of the transmission i.e. from which the
        * media is to be transmitted.
        *
        * @see #LOCAL_PORT_BASE_ARG_NAME
        */
       private int localPortBase;

       /**
        * The <tt>MediaStream</tt> instances initialized by this instance indexed
        * by their respective <tt>MediaType</tt> ordinal.
        */
       private MediaStream[] mediaStreams;

       /**
        * The <tt>InetAddress</tt> of the host which is the target of the
        * transmission i.e. to which the media is to be transmitted.
        *
        * @see #REMOTE_HOST_ARG_NAME
        */
       private InetAddress remoteAddr;

       /**
        * The port which is the target of the transmission i.e. to which the media
        * is to be transmitted.
        *
        * @see #REMOTE_PORT_BASE_ARG_NAME
        */
       private int remotePortBase;

       /**
        * Initializes a new <tt>AVTransmit2</tt> instance which is to transmit
        * audio and video to a specific host and a specific port.
        *
        * @param localPortBase  the port which is the source of the transmission
        *                       i.e. from which the media is to be transmitted
        * @param remoteHost     the name of the host which is the target of the
        *                       transmission i.e. to which the media is to be transmitted
        * @param remotePortBase the port which is the target of the transmission
        *                       i.e. to which the media is to be transmitted
        * @throws Exception if any error arises during the parsing of the specified
        *                   <tt>localPortBase</tt>, <tt>remoteHost</tt> and <tt>remotePortBase</tt>
        */
       private VideoTransmitter(
               String localPortBase,
               String remoteHost, String remotePortBase)
               throws Exception {
           this.localPortBase
                   = (localPortBase == null)
                   ? -1
                   : Integer.valueOf(localPortBase).intValue();
           this.remoteAddr = InetAddress.getByName(remoteHost);
           this.remotePortBase = Integer.valueOf(remotePortBase).intValue();
       }

       /**
        * Starts the transmission. Returns null if transmission started ok.
        * Otherwise it returns a string with the reason why the setup failed.
        */
       private String start()
               throws Exception {
           /*
            * Prepare for the start of the transmission i.e. initialize the
            * MediaStream instances.
            */
           MediaType[] mediaTypes = MediaType.values();
           MediaService mediaService = LibJitsi.getMediaService();
           int localPort = localPortBase;
           int remotePort = remotePortBase;

           mediaStreams = new MediaStream[mediaTypes.length];
           for (MediaType mediaType : mediaTypes) {
               if(mediaType != MediaType.VIDEO) continue;
               /*
                * The default MediaDevice (for a specific MediaType) is configured
                * (by the user of the application via some sort of UI) into the
                * ConfigurationService. If there is no ConfigurationService
                * instance known to LibJitsi, the first available MediaDevice of
                * the specified MediaType will be chosen by MediaService.
                */
               MediaDevice device
                       = mediaService.getMediaDeviceForPartialDesktopStreaming(100,100,100,100);
               if (device == null) {
                   continue;
               }
               MediaStream mediaStream = mediaService.createMediaStream(device);

               // direction
               /*
                * The AVTransmit2 example sends only and the AVReceive2 receives
                * only. In a call, the MediaStream's direction will most commonly
                * be set to SENDRECV.
                */
               mediaStream.setDirection(MediaDirection.SENDONLY);

               // format
               String encoding;
               double clockRate;
               /*
                * The AVTransmit2 and AVReceive2 examples use the H.264 video
                * codec. Its RTP transmission has no static RTP payload type number
                * assigned.
                */
               byte dynamicRTPPayloadType;

               switch (device.getMediaType()) {
                   case AUDIO:
                       encoding = "PCMU";
                       clockRate = 8000;
                   /* PCMU has a static RTP payload type number assigned. */
                       dynamicRTPPayloadType = -1;
                       break;
                   case VIDEO:
                       encoding = "H264";
                       clockRate = MediaFormatFactory.CLOCK_RATE_NOT_SPECIFIED;
                   /*
                    * The dymanic RTP payload type numbers are usually negotiated
                    * in the signaling functionality.
                    */
                       dynamicRTPPayloadType = 99;
                       break;
                   default:
                       encoding = null;
                       clockRate = MediaFormatFactory.CLOCK_RATE_NOT_SPECIFIED;
                       dynamicRTPPayloadType = -1;
               }

               if (encoding != null) {
                   MediaFormat format
                           = mediaService.getFormatFactory().createMediaFormat(
                           encoding,
                           clockRate);

                   /*
                    * The MediaFormat instances which do not have a static RTP
                    * payload type number association must be explicitly assigned
                    * a dynamic RTP payload type number.
                    */
                   if (dynamicRTPPayloadType != -1) {
                       mediaStream.addDynamicRTPPayloadType(
                               dynamicRTPPayloadType,
                               format);
                   }

                   mediaStream.setFormat(format);
               }

               // connector
               StreamConnector connector;

               if (localPortBase == -1) {
                   connector = new DefaultStreamConnector();
               } else {
                   int localRTPPort = localPort++;
                   int localRTCPPort = localPort++;

                   connector
                           = new DefaultStreamConnector(
                           new DatagramSocket(localRTPPort),
                           new DatagramSocket(localRTCPPort));
               }
               mediaStream.setConnector(connector);

               // target
               /*
                * The AVTransmit2 and AVReceive2 examples follow the common
                * practice that the RTCP port is right after the RTP port.
                */
               int remoteRTPPort = remotePort++;
               int remoteRTCPPort = remotePort++;

               mediaStream.setTarget(
                       new MediaStreamTarget(
                               new InetSocketAddress(remoteAddr, remoteRTPPort),
                               new InetSocketAddress(remoteAddr, remoteRTCPPort)));

               // name
               /*
                * The name is completely optional and it is not being used by the
                * MediaStream implementation at this time, it is just remembered so
                * that it can be retrieved via MediaStream#getName(). It may be
                * integrated with the signaling functionality if necessary.
                */
               mediaStream.setName(mediaType.toString());

               mediaStreams[mediaType.ordinal()] = mediaStream;
           }

           /*
            * Do start the transmission i.e. start the initialized MediaStream
            * instances.
            */
           for (MediaStream mediaStream : mediaStreams) {
               if (mediaStream != null) {

                   mediaStream.start();
               }
           }



           return null;
       }

       /**
        * Stops the transmission if already started
        */
       private void stop() {
           if (mediaStreams != null) {
               for (int i = 0; i &lt; mediaStreams.length; i++) {
                   MediaStream mediaStream = mediaStreams[i];

                   if (mediaStream != null) {
                       try {
                           mediaStream.stop();
                       } finally {
                           mediaStream.close();
                           mediaStreams[i] = null;
                       }
                   }
               }

               mediaStreams = null;
           }
       }

       /**
        * The name of the command-line argument which specifies the port from which
        * the media is to be transmitted. The command-line argument value will be
        * used as the port to transmit the audio RTP from, the next port after it
        * will be to transmit the audio RTCP from. Respectively, the subsequent
        * ports will be used to transmit the video RTP and RTCP from."
        */
       private static final String LOCAL_PORT_BASE_ARG_NAME
               = "--local-port-base=";

       /**
        * The name of the command-line argument which specifies the name of the
        * host to which the media is to be transmitted.
        */
       private static final String REMOTE_HOST_ARG_NAME = "--remote-host=";

       /**
        * The name of the command-line argument which specifies the port to which
        * the media is to be transmitted. The command-line argument value will be
        * used as the port to transmit the audio RTP to, the next port after it
        * will be to transmit the audio RTCP to. Respectively, the subsequent ports
        * will be used to transmit the video RTP and RTCP to."
        */
       private static final String REMOTE_PORT_BASE_ARG_NAME
               = "--remote-port-base=";

       /**
        * The list of command-line arguments accepted as valid by the
        * <tt>AVTransmit2</tt> application along with their human-readable usage
        * descriptions.
        */
       private static final String[][] ARGS
               = {
               {
                       LOCAL_PORT_BASE_ARG_NAME,
                       "The port which is the source of the transmission i.e. from"
                               + " which the media is to be transmitted. The specified"
                               + " value will be used as the port to transmit the audio"
                               + " RTP from, the next port after it will be used to"
                               + " transmit the audio RTCP from. Respectively, the"
                               + " subsequent ports will be used to transmit the video RTP"
                               + " and RTCP from."
               },
               {
                       REMOTE_HOST_ARG_NAME,
                       "The name of the host which is the target of the transmission"
                               + " i.e. to which the media is to be transmitted"
               },
               {
                       REMOTE_PORT_BASE_ARG_NAME,
                       "The port which is the target of the transmission i.e. to which"
                               + " the media is to be transmitted. The specified value"
                               + " will be used as the port to transmit the audio RTP to"
                               + " the next port after it will be used to transmit the"
                               + " audio RTCP to. Respectively, the subsequent ports will"
                               + " be used to transmit the video RTP and RTCP to."
               }
       };

       public static void main(String[] args)
               throws Exception {
           // We need two parameters to do the transmission. For example,
           // ant run-example -Drun.example.name=AVTransmit2 -Drun.example.arg.line="--remote-host=127.0.0.1 --remote-port-base=10000"
           if (args.length &lt; 2) {
               prUsage();
           } else {
               Map argMap = parseCommandLineArgs(args);

               LibJitsi.start();
               try {
                   // Create a audio transmit object with the specified params.
                   VideoTransmitter at
                           = new VideoTransmitter(
                           argMap.get(LOCAL_PORT_BASE_ARG_NAME),
                           argMap.get(REMOTE_HOST_ARG_NAME),
                           argMap.get(REMOTE_PORT_BASE_ARG_NAME));
                   // Start the transmission
                   String result = at.start();

                   // result will be non-null if there was an error. The return
                   // value is a String describing the possible error. Print it.
                   if (result == null) {
                       System.err.println("Start transmission for 600 seconds...");

                       // Transmit for 60 seconds and then close the processor
                       // This is a safeguard when using a capture data source
                       // so that the capture device will be properly released
                       // before quitting.
                       // The right thing to do would be to have a GUI with a
                       // "Stop" button that would call stop on AVTransmit2
                       try {
                           Thread.sleep(600_000);
                       } catch (InterruptedException ie) {
                       }

                       // Stop the transmission
                       at.stop();

                       System.err.println("...transmission ended.");
                   } else {
                       System.err.println("Error : " + result);
                   }
               } finally {
                   LibJitsi.stop();
               }
           }
       }

       /**
        * Parses the arguments specified to the <tt>AVTransmit2</tt> application on
        * the command line.
        *
        * @param args the arguments specified to the <tt>AVTransmit2</tt>
        *             application on the command line
        * @return a <tt>Map</tt> containing the arguments specified to the
        * <tt>AVTransmit2</tt> application on the command line in the form of
        * name-value associations
        */
       static Map parseCommandLineArgs(String[] args) {
           Map argMap = new HashMap();

           for (String arg : args) {
               int keyEndIndex = arg.indexOf('=');
               String key;
               String value;

               if (keyEndIndex == -1) {
                   key = arg;
                   value = null;
               } else {
                   key = arg.substring(0, keyEndIndex + 1);
                   value = arg.substring(keyEndIndex + 1);
               }
               argMap.put(key, value);
           }
           return argMap;
       }

       /**
        * Outputs human-readable description about the usage of the
        * <tt>AVTransmit2</tt> application and the command-line arguments it
        * accepts as valid.
        */
       private static void prUsage() {
           PrintStream err = System.err;

           err.println("Usage: " + VideoTransmitter.class.getName() + " <args>");
           err.println("Valid args:");
           for (String[] arg : ARGS)
               err.println("  " + arg[0] + " " + arg[1]);
       }
       }
    </args>
  • Decoding erroeneous h264 encoded mp4 file using ffmpeg

    30 décembre 2014, par Masoud

    I’m trying to decode some h264 encoded video files corrupted during transmission. feeding erroneous file to ffmpeg to convert it to raw video format(YUV format), it keeps saying this massages multiple times with multiple sizes :

    [h264 @ 0x7f8cc100f800] AVC : nal size 34763
    [h264 @ 0x7f8cc100f800] no frame !

    and the result is no frame decoded !
    I tried finding nal units in original file and manually replacing 0x00 00 01 xx into corrupted file, but it didn’t help.

    thanks