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  • Supporting all media types

    13 avril 2011, par

    Unlike most software and media-sharing platforms, MediaSPIP aims to manage as many different media types as possible. The following are just a few examples from an ever-expanding list of supported formats : images : png, gif, jpg, bmp and more audio : MP3, Ogg, Wav and more video : AVI, MP4, OGV, mpg, mov, wmv and more text, code and other data : OpenOffice, Microsoft Office (Word, PowerPoint, Excel), web (html, CSS), LaTeX, Google Earth and (...)

  • Ajouter notes et légendes aux images

    7 février 2011, par

    Pour pouvoir ajouter notes et légendes aux images, la première étape est d’installer le plugin "Légendes".
    Une fois le plugin activé, vous pouvez le configurer dans l’espace de configuration afin de modifier les droits de création / modification et de suppression des notes. Par défaut seuls les administrateurs du site peuvent ajouter des notes aux images.
    Modification lors de l’ajout d’un média
    Lors de l’ajout d’un média de type "image" un nouveau bouton apparait au dessus de la prévisualisation (...)

  • List of compatible distributions

    26 avril 2011, par

    The table below is the list of Linux distributions compatible with the automated installation script of MediaSPIP. Distribution nameVersion nameVersion number Debian Squeeze 6.x.x Debian Weezy 7.x.x Debian Jessie 8.x.x Ubuntu The Precise Pangolin 12.04 LTS Ubuntu The Trusty Tahr 14.04
    If you want to help us improve this list, you can provide us access to a machine whose distribution is not mentioned above or send the necessary fixes to add (...)

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  • seeking with av_seek_frame returns invalid data

    27 juin 2016, par mtadmk

    Based on dranger tutorial I’m trying to implement seeking in video file. Problem is with seeking to beginning milliseconds - it always returns 0 when seeking backward, or some place in file (based on file format).

    I.e. with this video file and seeking forward to 500 pts there is always 6163 pts returned. Seeking backward to 500 is always returning 0. I have no idea why.

    Code to do this :

    import java.util.Arrays;
    
import java.util.List;
    
import org.bytedeco.javacpp.BytePointer;
    
import org.bytedeco.javacpp.DoublePointer;
    
import org.bytedeco.javacpp.PointerPointer;
    
import org.bytedeco.javacpp.avcodec;
    
import org.bytedeco.javacpp.avformat;
    
import org.bytedeco.javacpp.avutil;
    
import org.bytedeco.javacpp.swscale;
    

    
import static org.bytedeco.javacpp.avcodec.av_free_packet;
    
import static org.bytedeco.javacpp.avcodec.avcodec_close;
    
import static org.bytedeco.javacpp.avcodec.avcodec_decode_video2;
    
import static org.bytedeco.javacpp.avcodec.avcodec_find_decoder;
    
import static org.bytedeco.javacpp.avcodec.avcodec_flush_buffers;
    
import static org.bytedeco.javacpp.avcodec.avcodec_open2;
    
import static org.bytedeco.javacpp.avcodec.avpicture_fill;
    
import static org.bytedeco.javacpp.avcodec.avpicture_get_size;
    
import static org.bytedeco.javacpp.avformat.AVSEEK_FLAG_BACKWARD;
    
import static org.bytedeco.javacpp.avformat.av_dump_format;
    
import static org.bytedeco.javacpp.avformat.av_read_frame;
    
import static org.bytedeco.javacpp.avformat.av_register_all;
    
import static org.bytedeco.javacpp.avformat.av_seek_frame;
    
import static org.bytedeco.javacpp.avformat.avformat_close_input;
    
import static org.bytedeco.javacpp.avformat.avformat_find_stream_info;
    
import static org.bytedeco.javacpp.avformat.avformat_open_input;
    
import static org.bytedeco.javacpp.avutil.AVMEDIA_TYPE_VIDEO;
    
import static org.bytedeco.javacpp.avutil.AV_PIX_FMT_RGB24;
    
import static org.bytedeco.javacpp.avutil.AV_TIME_BASE;
    
import static org.bytedeco.javacpp.avutil.av_frame_alloc;
    
import static org.bytedeco.javacpp.avutil.av_frame_get_best_effort_timestamp;
    
import static org.bytedeco.javacpp.avutil.av_free;
    
import static org.bytedeco.javacpp.avutil.av_make_q;
    
import static org.bytedeco.javacpp.avutil.av_malloc;
    
import static org.bytedeco.javacpp.avutil.av_q2d;
    
import static org.bytedeco.javacpp.avutil.av_rescale_q;
    
import static org.bytedeco.javacpp.swscale.SWS_BILINEAR;
    
import static org.bytedeco.javacpp.swscale.sws_getContext;
    
import static org.bytedeco.javacpp.swscale.sws_scale;
    

    
public class SeekTest1 {
    
    private avformat.AVFormatContext videoFile;
    
    private final avcodec.AVPacket framePacket = new avcodec.AVPacket();
    
    private avcodec.AVCodecContext videoCodec;
    
    private avutil.AVFrame yuvFrame;
    
    private swscale.SwsContext scalingContext;
    
    private avutil.AVFrame rgbFrame;
    
    private int streamId;
    
    private long lastTime;
    

    
    public static void main(String[] args) {
    
        if (args.length > 0) {
    
            new SeekTest1().start(args[0]);
    
        } else {
    
            new SeekTest1().start("/path/to/file");
    
        }
    

    
    }
    

    
    private void start(String path) {
    
        init(path);
    
        //test for forward
    
//        List<integer> seekPos = Arrays.asList(0, 100, 0, 200, 0, 300, 0, 400, 0, 500, 0, 600, 0, 700);
    
        //test for backward
    
        List<integer> seekPos = Arrays.asList(10000, 8000, 10000, 7000, 10000, 6000, 10000, 4000, 10000, 2000, 10000, 1000, 10000, 200);
    
        seekPos.forEach(seekPosition -> {
    
            readFrame();
    
            seek(seekPosition);
    
        });
    
        readFrame();
    
        cleanUp();
    
    }
    

    
    long seek(long seekPosition) {
    
        final avutil.AVRational timeBase = fetchTimeBase();
    
        long timeInBaseUnit = fetchTimeInBaseUnit(seekPosition, timeBase);
    

    
        //changing flag to AVSEEK_FLAG_ANY does not change behavior
    
        int flag = 0;
    
        if (timeInBaseUnit &lt; lastTime) {
    
            flag = AVSEEK_FLAG_BACKWARD;
    
            System.out.println("seeking backward to " + timeInBaseUnit);
    
        } else {
    
            System.out.println("seeking forward to " + timeInBaseUnit);
    
        }
    
        avcodec_flush_buffers(videoCodec);
    
        av_seek_frame(videoFile, streamId, timeInBaseUnit, flag);
    
        return timeInBaseUnit;
    
    }
    

    
    private long fetchTimeInBaseUnit(long seekPositionMillis, avutil.AVRational timeBase) {
    
        return av_rescale_q((long) (seekPositionMillis / 1000.0 * AV_TIME_BASE), av_make_q(1, AV_TIME_BASE), timeBase);
    
    }
    

    
    private void readFrame() {
    
        while (av_read_frame(videoFile, framePacket) >= 0) {
    
            if (framePacket.stream_index() == streamId) {
    
                // Decode video frame
    
                final int[] frameFinished = new int[1];
    
                avcodec_decode_video2(this.videoCodec, yuvFrame, frameFinished, framePacket);
    

    
                if (frameFinished[0] != 0) {
    
                    av_free_packet(framePacket);
    
                    long millis = produceFinishedFrame();
    
                    System.out.println("produced time " + millis);
    
                    break;
    
                }
    
            }
    
            av_free_packet(framePacket);
    
        }
    
    }
    

    
    private long produceFinishedFrame() {
    
        sws_scale(scalingContext, yuvFrame.data(), yuvFrame.linesize(), 0,
    
            videoCodec.height(), rgbFrame.data(), rgbFrame.linesize());
    
        final long pts = av_frame_get_best_effort_timestamp(yuvFrame);
    
        final double timeBase = av_q2d(fetchTimeBase());
    
        final long foundMillis = (long) (pts * 1000 * timeBase);
    
        lastTime = foundMillis;
    
        return foundMillis;
    
    }
    

    
    private avutil.AVRational fetchTimeBase() {
    
        return videoFile.streams(streamId).time_base();
    
    }
    

    
    private void init(String videoPath) {
    
        final avformat.AVFormatContext videoFile = new avformat.AVFormatContext(null);
    

    
        av_register_all();
    
        if (avformat_open_input(videoFile, videoPath, null, null) != 0) throw new RuntimeException("unable to open");
    
        if (avformat_find_stream_info(videoFile, (PointerPointer) null) &lt; 0) throw new RuntimeException("Couldn't find stream information");
    

    
        av_dump_format(videoFile, 0, videoPath, 0);
    

    
        final int streamId = findFirstVideoStream(videoFile);
    

    
        final avcodec.AVCodecContext codec = videoFile.streams(streamId).codec();
    

    
        final avcodec.AVCodec pCodec = avcodec_find_decoder(codec.codec_id());
    
        if (pCodec == null) throw new RuntimeException("Unsupported codec");
    

    
        if (avcodec_open2(codec, pCodec, (avutil.AVDictionary) null) &lt; 0) throw new RuntimeException("Could not open codec");
    

    
        final avutil.AVFrame yuvFrame = av_frame_alloc();
    

    
        final avutil.AVFrame rgbFrame = av_frame_alloc();
    
        if (rgbFrame == null) throw new RuntimeException("Can't allocate avframe");
    

    
        final int numBytes = avpicture_get_size(AV_PIX_FMT_RGB24, codec.width(), codec.height());
    
        final BytePointer frameBuffer = new BytePointer(av_malloc(numBytes));
    

    
        final swscale.SwsContext swsContext = sws_getContext(codec.width(), codec.height(), codec.pix_fmt(), codec.width(), codec.height(),
    
            AV_PIX_FMT_RGB24, SWS_BILINEAR, null, null, (DoublePointer) null);
    

    
        avpicture_fill(new avcodec.AVPicture(rgbFrame), frameBuffer, AV_PIX_FMT_RGB24, codec.width(), codec.height());
    

    
        this.videoFile = videoFile;
    
        this.videoCodec = codec;
    
        this.yuvFrame = yuvFrame;
    
        this.scalingContext = swsContext;
    
        this.rgbFrame = rgbFrame;
    
        this.streamId = streamId;
    
    }
    

    
    private static int findFirstVideoStream(avformat.AVFormatContext videoFile) {
    
        int videoStream = -1;
    
        for (int i = 0; i &lt; videoFile.nb_streams(); i++) {
    
            if (videoFile.streams(i).codec().codec_type() == AVMEDIA_TYPE_VIDEO) {
    
                videoStream = i;
    
                break;
    
            }
    
        }
    
        if (videoStream == -1) throw new RuntimeException("Didn't find video stream");
    
        return videoStream;
    
    }
    

    
    private void cleanUp() {
    
        av_free(this.rgbFrame);
    
        av_free(yuvFrame);
    
        avcodec_close(videoCodec);
    
        avformat_close_input(videoFile);
    
    }
    
}
    
</integer></integer>

    As input arg should be provided file from above.

  • Révision 98073 : Report de r98071 : Report de r98068 : Certains flux RSS publient l’integralite de...

    26 mai 2016, par cedric@yterium.com

    On optimise les fonctions cdata_echappe et cdata_echappe_retour, et on limite la syndication aux 1000 premiers items, surchargeable par la constante _SYNDICATION_MAX_ITEMS

  • Révision 98074 : Report de r98072 : Report de r98068 : Certains flux RSS publient l’integralite de...

    26 mai 2016, par cedric@yterium.com

    On optimise les fonctions cdata_echappe et cdata_echappe_retour, et on limite la syndication aux 1000 premiers items, surchargeable par la constante _SYNDICATION_MAX_ITEMS

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