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    12 avril 2011, par

    Chaque 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.
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  • Configurer la prise en compte des langues

    15 novembre 2010, par

    Accéder à la configuration et ajouter des langues prises en compte
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    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.
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  • XMP PHP

    13 mai 2011, par

    Dixit 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.
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Sur d’autres sites (13876)

  • Applying same filter_complex many times before output [duplicate]

    19 août 2019, par Fabián

    It’s not a duplicate. This is about using filter_complex, not -vf.

    In my video there’s an object that has shades of yellow (more orange-like) and a solid yellow as background.

    I need to output all frames into a png sequence, using a color key filter to replace the yellow from the background :

    ffmpeg -ss 4 -i original.mp4 -t 2 -filter_complex "[0:v]colorkey=0xfff31b:0.125:0[ckout]" -map "[ckout]" colorkey-%d.png

    This removes the specific color, but leaves some pints behind, and some items are yellow-themed, so blending value is a no-no for this scenario.

    I need to get rid of 4 specific yellow-colors from the frames : 0xfff31b, 0xfae56b, 0xfaec46 and 0xeee2a0, and I plan to run the same filter for specific colors before getting the final result.

    So first I tried this :

    ffmpeg -ss 4 -i original.mp4 -t 2 -filter_complex "[0:v]colorkey=0xfff31b:0.4:0[ckout1];[0:v]colorkey=0xfae56b:0.4:0[ckout2];[0:v]colorkey=0xfaec46:0.4:0[ckout3];[0:v]colorkey=0xeee2a0:0.4:0[ckout4]" -map "[ckout4]" colorkeyrefined-%d.png

    Then this :

    ffmpeg -ss 4 -i original.mp4 -t 2 -filter_complex "[0:v]colorkey=0xfff31b:0.4:0[ckout]" -filter_complex "[0:v]colorkey=0xfae56b:0.4:0[ckout]" -filter_complex "[0:v]colorkey=0xfaec46:0.4:0[ckout]" -filter_complex "[0:v]colorkey=0xeee2a0:0.4:0[ckout]" -map "[ckout]" colorkeyrefined-%d.png

    But both display the same error :

    Filter colorkey has an unconnected output.

    Is there a way to apply the colorkey feature 4 times (with the mentioned values) in one go ?

  • Build ffmpeg on a build machine

    18 juillet 2019, par RDI

    Build ffmpeg on build PC using libx264 and shared libraries (not static).
    I am building on a Red Hat 6.6 Server and final target machine is CentOS 6.6.
    I am trying, as said, to build ffmpeg with encoding enabled (with libx264) and shared libraries ; of course I do not want to install the libraries on the build PC, they should be only extracted and then delivered together with the final RPM.
    After the "./configure" I get all RPMs (related to ffmpeg) but when trying to installing ffmpeg-libs on the build pc it fails because the libx264.so.157 is not found, even if as test I installed it (configure/make/make install) and present at /usr/local/lib.

    Where am I wrong ?

    Thanks

    This is my SPEC file at the moment :

    ldconfig /usr/local/lib
    export LD_LIBRARY_PATH=/usr/local/lib:$LD_LIBRARY_PATH


    # configure
    ./configure \
    --enable-gpl --disable-static --enable-shared --extra-cflags="-I/usr/local/include" --extra-ldflags="-L/usr/local/lib" --extra-libs=-ldl --disable-autodetect --disable-doc --disable-postproc --disable-ffplay --disable-everything --enable-encoder=aac --enable-encoder=png --enable-encoder=mjpeg --enable-encoder=libx264 --enable-decoder=aac --enable-decoder=h264 --enable-decoder=mpeg4 --enable-decoder=rawvideo --enable-decoder=png --enable-muxer=mp4 --enable-muxer=stream_segment --enable-muxer=image2 --enable-demuxer=aac --enable-demuxer=h264 --enable-demuxer=mov --enable-demuxer=rtp --enable-parser=aac --enable-parser=h264 --enable-parser=mpeg4video --enable-bsf=aac_adtstoasc --enable-protocol=file --enable-protocol=http --enable-protocol=tcp --enable-protocol=rtp --enable-protocol=udp --enable-indev=xcbgrab --disable-alsa --enable-libxcb --enable-libxcb-xfixes --enable-libxcb-shape --enable-zlib --prefix=%{_prefix} --bindir=%{_bindir} --datadir=%{_datadir}/%{name} --shlibdir=%{_libdir} --enable-alsa --enable-avfilter --enable-avresample --enable-libx264 --enable-filter=scale \
  • Decode audio using ffmpeg (packet-by-packet) in Java

    27 mai 2022, par quad478

    In 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;&#xA;&#xA;import io.netty.buffer.ByteBuf;&#xA;import io.netty.channel.ChannelHandlerContext;&#xA;import io.netty.handler.codec.MessageToMessageDecoder;&#xA;&#xA;import java.io.Closeable;&#xA;import java.io.IOException;&#xA;import java.io.InputStream;&#xA;import java.io.OutputStream;&#xA;import java.util.List;&#xA;import java.util.concurrent.ExecutorService;&#xA;import java.util.concurrent.Executors;&#xA;import java.util.concurrent.Future;&#xA;&#xA;public class RtpFfmpegDecoder extends MessageToMessageDecoder<rtppacket> implements Closeable {&#xA;&#xA;    private final Process ffmegProcess;&#xA;    private final OutputStream ffmpegOutput;&#xA;    private final InputStream ffmegInput;&#xA;    private final ExecutorService ffmpegInputReaderService = Executors.newSingleThreadExecutor();&#xA;&#xA;    public RtpFfmpegDecoder() {&#xA;&#xA;        //Start Ffmpeg process&#xA;        ProcessBuilder ffmpegBuilder = new ProcessBuilder("ffmpeg.exe", "-f", "mulaw",&#xA;                "-re", "-i", "-", "-f", "adts", "-").redirectError(ProcessBuilder.Redirect.INHERIT);&#xA;        try {&#xA;            ffmegProcess = ffmpegBuilder.start();&#xA;            ffmpegOutput = ffmegProcess.getOutputStream();&#xA;            ffmegInput = ffmegProcess.getInputStream();&#xA;        } catch (IOException e) {&#xA;            throw new IllegalStateException(e);&#xA;        }&#xA;    }&#xA;&#xA;    @Override&#xA;    protected void decode(ChannelHandlerContext channelHandlerContext, RtpPacket rtpPacket, List list) throws Exception {&#xA;&#xA;        //start read ffmpeg output in another thread&#xA;        Future future = ffmpegInputReaderService.submit(this::startReadFFmpegOutput);&#xA;&#xA;        //write rtp- packet bytes to ffmpeg-input&#xA;        ByteBuf data = rtpPacket.getData();&#xA;        byte[] rtpData = new byte[data.readableBytes()];&#xA;        data.getBytes(data.readerIndex(), rtpData);&#xA;        ffmpegOutput.write(rtpData);&#xA;        ffmpegOutput.flush();&#xA;&#xA;        //waiting here for the decoding result from ffmpeg&#xA;        //blocks here&#xA;        byte[] result = future.get();&#xA;        //then process result...&#xA;    }&#xA;&#xA;    private byte[] startReadFFmpegOutput() {&#xA;        try {&#xA;            //I don&#x27;t know how many bytes to expect here, for test purposes I use 1024&#xA;            var bytes = new byte[1024];&#xA;            ffmegInput.read(bytes);&#xA;            return bytes;&#xA;        } catch (IOException e) {&#xA;            throw new IllegalStateException(e);&#xA;        }&#xA;    }&#xA;&#xA;    @Override&#xA;    public void close() throws IOException {&#xA;        //Close streams code...&#xA;    }&#xA;}&#xA;</rtppacket>

    &#xA;

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

    &#xA;

    byte[] result = future.get();&#xA;

    &#xA;

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

    &#xA;

    I would be very grateful for any help

    &#xA;