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  • Librairies et logiciels spécifiques aux médias

    10 décembre 2010, par

    Pour un fonctionnement correct et optimal, plusieurs choses sont à prendre en considération.
    Il est important, après avoir installé apache2, mysql et php5, d’installer d’autres logiciels nécessaires dont les installations sont décrites dans les liens afférants. Un ensemble de librairies multimedias (x264, libtheora, libvpx) utilisées pour l’encodage et le décodage des vidéos et sons afin de supporter le plus grand nombre de fichiers possibles. Cf. : ce tutoriel ; FFMpeg avec le maximum de décodeurs et (...)

  • Organiser par catégorie

    17 mai 2013, par

    Dans MédiaSPIP, une rubrique a 2 noms : catégorie et rubrique.
    Les différents documents stockés dans MédiaSPIP peuvent être rangés dans différentes catégories. On peut créer une catégorie en cliquant sur "publier une catégorie" dans le menu publier en haut à droite ( après authentification ). Une catégorie peut être rangée dans une autre catégorie aussi ce qui fait qu’on peut construire une arborescence de catégories.
    Lors de la publication prochaine d’un document, la nouvelle catégorie créée sera proposée (...)

  • Récupération d’informations sur le site maître à l’installation d’une instance

    26 novembre 2010, par

    Utilité
    Sur le site principal, une instance de mutualisation est définie par plusieurs choses : Les données dans la table spip_mutus ; Son logo ; Son auteur principal (id_admin dans la table spip_mutus correspondant à un id_auteur de la table spip_auteurs)qui sera le seul à pouvoir créer définitivement l’instance de mutualisation ;
    Il peut donc être tout à fait judicieux de vouloir récupérer certaines de ces informations afin de compléter l’installation d’une instance pour, par exemple : récupérer le (...)

Sur d’autres sites (5668)

  • My journey to Coviu

    27 octobre 2015, par silvia

    My new startup just released our MVP – this is the story of what got me here.

    I love creating new applications that let people do their work better or in a manner that wasn’t possible before.

    German building and loan socityMy first such passion was as a student intern when I built a system for a building and loan association’s monthly customer magazine. The group I worked with was managing their advertiser contacts through a set of paper cards and I wrote a dBase based system (yes, that long ago) that would manage their customer relationships. They loved it – until it got replaced by an SAP system that cost 100 times what I cost them, had really poor UX, and only gave them half the functionality. It was a corporate system with ongoing support, which made all the difference to them.

    Dr Scholz und Partner GmbHThe story repeated itself with a CRM for my Uncle’s construction company, and with a resume and quotation management system for Accenture right after Uni, both of which I left behind when I decided to go into research.

    Even as a PhD student, I never lost sight of challenges that people were facing and wanted to develop technology to overcome problems. The aim of my PhD thesis was to prepare for the oncoming onslaught of audio and video on the Internet (yes, this was 1994 !) by developing algorithms to automatically extract and locate information in such files, which would enable users to structure, index and search such content.

    Many of the use cases that we explored are now part of products or continue to be challenges : finding music that matches your preferences, identifying music or video pieces e.g. to count ads on the radio or to mark copyright infringement, or the automated creation of video summaries such as trailers.

    CSIRO

    This continued when I joined the CSIRO in Australia – I was working on segmenting speech into words or talk spurts since that would simplify captioning & subtitling, and on MPEG-7 which was a (slightly over-engineered) standard to structure metadata about audio and video.

    In 2001 I had the idea of replicating the Web for videos : i.e. creating hyperlinked and searchable video-only experiences. We called it “Annodex” for annotated and indexed video and it needed full-screen hyperlinked video in browsers – man were we ahead of our time ! It was my first step into standards, got several IETF RFCs to my name, and started my involvement with open codecs through Xiph.

    vquence logoAround the time that YouTube was founded in 2006, I founded Vquence – originally a video search company for the Web, but pivoted to a video metadata mining company. Vquence still exists and continues to sell its data to channel partners, but it lacks the user impact that has always driven my work.

    As the video element started being developed for HTML5, I had to get involved. I contributed many use cases to the W3C, became a co-editor of the HTML5 spec and focused on video captioning with WebVTT while contracting to Mozilla and later to Google. We made huge progress and today the technology exists to publish video on the Web with captions, making the Web more inclusive for everybody. I contributed code to YouTube and Google Chrome, but was keen to make a bigger impact again.

    NICTA logoThe opportunity came when a couple of former CSIRO colleagues who now worked for NICTA approached me to get me interested in addressing new use cases for video conferencing in the context of WebRTC. We worked on a kiosk-style solution to service delivery for large service organisations, particularly targeting government. The emerging WebRTC standard posed many technical challenges that we addressed by building rtc.io , by contributing to the standards, and registering bugs on the browsers.

    Fast-forward through the development of a few further custom solutions for customers in health and education and we are starting to see patterns of need emerge. The core learning that we’ve come away with is that to get things done, you have to go beyond “talking heads” in a video call. It’s not just about seeing the other person, but much more about having a shared view of the things that need to be worked on and a shared way of interacting with them. Also, we learnt that the things that are being worked on are quite varied and may include multiple input cameras, digital documents, Web pages, applications, device data, controls, forms.

    Coviu logoSo we set out to build a solution that would enable productive remote collaboration to take place. It would need to provide an excellent user experience, it would need to be simple to work with, provide for the standard use cases out of the box, yet be architected to be extensible for specialised data sharing needs that we knew some of our customers had. It would need to be usable directly on Coviu.com, but also able to integrate with specialised applications that some of our customers were already using, such as the applications that they spend most of their time in (CRMs, practice management systems, learning management systems, team chat systems). It would need to require our customers to sign up, yet their clients to join a call without sign-up.

    Collaboration is a big problem. People are continuing to get more comfortable with technology and are less and less inclined to travel distances just to get a service done. In a country as large as Australia, where 12% of the population lives in rural and remote areas, people may not even be able to travel distances, particularly to receive or provide recurring or specialised services, or to achieve work/life balance. To make the world a global village, we need to be able to work together better remotely.

    The need for collaboration is being recognised by specialised Web applications already, such as the LiveShare feature of Invision for Designers, Codassium for pair programming, or the recently announced Dropbox Paper. Few go all the way to video – WebRTC is still regarded as a complicated feature to support.

    Coviu in action

    With Coviu, we’d like to offer a collaboration feature to every Web app. We now have a Web app that provides a modern and beautifully designed collaboration interface. To enable other Web apps to integrate it, we are now developing an API. Integration may entail customisation of the data sharing part of Coviu – something Coviu has been designed for. How to replicate the data and keep it consistent when people collaborate remotely – that is where Coviu makes a difference.

    We have started our journey and have just launched free signup to the Coviu base product, which allows individuals to own their own “room” (i.e. a fixed URL) in which to collaborate with others. A huge shout out goes to everyone in the Coviu team – a pretty amazing group of people – who have turned the app from an idea to reality. You are all awesome !

    With Coviu you can share and annotate :

    • images (show your mum photos of your last holidays, or get feedback on an architecture diagram from a customer),
    • pdf files (give a presentation remotely, or walk a customer through a contract),
    • whiteboards (brainstorm with a colleague), and
    • share an application window (watch a YouTube video together, or work through your task list with your colleagues).

    All of these are regarded as “shared documents” in Coviu and thus have zooming and annotations features and are listed in a document tray for ease of navigation.

    This is just the beginning of how we want to make working together online more productive. Give it a go and let us know what you think.

    http://coviu.com/

    The post My journey to Coviu first appeared on ginger’s thoughts.

  • Scale filter crashes with error when used from transcoding example

    27 juin 2017, par Vali

    I’ve modified a bit (just to compile in c++) this code example :
    https://github.com/FFmpeg/FFmpeg/blob/master/doc/examples/transcoding.c.

    What works : as is (null filter), a number of other filters like framerate, drawtext, ...

    What doesn’t work : scale filter when scaling down.

    I use the following syntax for scale ( I’ve tried many others also, same effect) :
    "scale=w=iw/2 :-1"

    The error is : "Input picture width (240) is greater than stride (128)" where the values for width and stride depend on the input.

    Misc environment info : windows, VS 2017, input example : rtsp ://wowzaec2demo.streamlock.net/vod/mp4:BigBuckBunny_115k.mov

    Any clue as to what I’m doing wrong ?

    Thanks !


    EDITED to add working code sample


    #pragma comment(lib, "avcodec.lib")
    #pragma comment(lib, "avutil.lib")
    #pragma comment(lib, "avformat.lib")
    #pragma comment(lib, "avfilter.lib")

    /*
    * Copyright (c) 2010 Nicolas George
    * Copyright (c) 2011 Stefano Sabatini
    * Copyright (c) 2014 Andrey Utkin
    *
    **** EDITED 2017 for testing (see original here: https://github.com/FFmpeg/FFmpeg/blob/master/doc/examples/transcoding.c)
    *
    * Permission is hereby granted, free of charge, to any person obtaining a copy
    * of this software and associated documentation files (the "Software"), to deal
    * in the Software without restriction, including without limitation the rights
    * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
    * copies of the Software, and to permit persons to whom the Software is
    * furnished to do so, subject to the following conditions:
    *
    * The above copyright notice and this permission notice shall be included in
    * all copies or substantial portions of the Software.
    *
    * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
    * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
    * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
    * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
    * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
    * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
    * THE SOFTWARE.
    */

    /**
    * @file
    * API example for demuxing, decoding, filtering, encoding and muxing
    * @example transcoding.c
    */

    extern "C"
    {
       #include <libavcodec></libavcodec>avcodec.h>
       #include <libavformat></libavformat>avformat.h>
       #include <libavfilter></libavfilter>avfiltergraph.h>
       #include <libavfilter></libavfilter>buffersink.h>
       #include <libavfilter></libavfilter>buffersrc.h>
       #include <libavutil></libavutil>opt.h>
       #include <libavutil></libavutil>pixdesc.h>
    }


    static AVFormatContext *ifmt_ctx;
    static AVFormatContext *ofmt_ctx;
    typedef struct FilteringContext {
       AVFilterContext *buffersink_ctx;
       AVFilterContext *buffersrc_ctx;
       AVFilterGraph *filter_graph;
    } FilteringContext;
    static FilteringContext *filter_ctx;

    typedef struct StreamContext {
       AVCodecContext *dec_ctx;
       AVCodecContext *enc_ctx;
    } StreamContext;
    static StreamContext *stream_ctx;

    static int open_input_file(const char *filename, int&amp; videoStreamIndex)
    {
       int ret;
       unsigned int i;

       ifmt_ctx = NULL;
       if ((ret = avformat_open_input(&amp;ifmt_ctx, filename, NULL, NULL)) &lt; 0) {
           av_log(NULL, AV_LOG_ERROR, "Cannot open input file\n");
           return ret;
       }

       if ((ret = avformat_find_stream_info(ifmt_ctx, NULL)) &lt; 0) {
           av_log(NULL, AV_LOG_ERROR, "Cannot find stream information\n");
           return ret;
       }

       // Just need video
       videoStreamIndex = -1;
       for (unsigned int i = 0; i &lt; ifmt_ctx->nb_streams; i++)
       {
           if (ifmt_ctx->streams[i]->codecpar->codec_type != AVMEDIA_TYPE_VIDEO)
               continue;
           videoStreamIndex = i;
           break;
       }
       if (videoStreamIndex &lt; 0)
       {
           av_log(NULL, AV_LOG_ERROR, "Cannot find video stream\n");
           return videoStreamIndex;
       }


       stream_ctx = (StreamContext*)av_mallocz_array(ifmt_ctx->nb_streams, sizeof(*stream_ctx));
       if (!stream_ctx)
           return AVERROR(ENOMEM);

       for (i = 0; i &lt; ifmt_ctx->nb_streams; i++) {

           // Just need video
           if (i != videoStreamIndex)
               continue;


           AVStream *stream = ifmt_ctx->streams[i];
           AVCodec *dec = avcodec_find_decoder(stream->codecpar->codec_id);
           AVCodecContext *codec_ctx;
           if (!dec) {
               av_log(NULL, AV_LOG_ERROR, "Failed to find decoder for stream #%u\n", i);
               return AVERROR_DECODER_NOT_FOUND;
           }
           codec_ctx = avcodec_alloc_context3(dec);
           if (!codec_ctx) {
               av_log(NULL, AV_LOG_ERROR, "Failed to allocate the decoder context for stream #%u\n", i);
               return AVERROR(ENOMEM);
           }
           ret = avcodec_parameters_to_context(codec_ctx, stream->codecpar);
           if (ret &lt; 0) {
               av_log(NULL, AV_LOG_ERROR, "Failed to copy decoder parameters to input decoder context "
                   "for stream #%u\n", i);
               return ret;
           }
           /* Reencode video &amp; audio and remux subtitles etc. */
           if (codec_ctx->codec_type == AVMEDIA_TYPE_VIDEO
               || codec_ctx->codec_type == AVMEDIA_TYPE_AUDIO) {
               if (codec_ctx->codec_type == AVMEDIA_TYPE_VIDEO)
                   codec_ctx->framerate = av_guess_frame_rate(ifmt_ctx, stream, NULL);
               /* Open decoder */
               ret = avcodec_open2(codec_ctx, dec, NULL);
               if (ret &lt; 0) {
                   av_log(NULL, AV_LOG_ERROR, "Failed to open decoder for stream #%u\n", i);
                   return ret;
               }
           }
           stream_ctx[i].dec_ctx = codec_ctx;
       }

       av_dump_format(ifmt_ctx, 0, filename, 0);
       return 0;
    }

    static int open_output_file(const char *filename, const int videoStreamIndex)
    {
       AVStream *out_stream;
       AVStream *in_stream;
       AVCodecContext *dec_ctx, *enc_ctx;
       AVCodec *encoder;
       int ret;
       unsigned int i;

       ofmt_ctx = NULL;
       avformat_alloc_output_context2(&amp;ofmt_ctx, NULL, NULL, filename);
       if (!ofmt_ctx) {
           av_log(NULL, AV_LOG_ERROR, "Could not create output context\n");
           return AVERROR_UNKNOWN;
       }


       for (i = 0; i &lt; ifmt_ctx->nb_streams; i++) {
           // Just need video
           if (i != videoStreamIndex)
               continue;

           out_stream = avformat_new_stream(ofmt_ctx, NULL);
           if (!out_stream) {
               av_log(NULL, AV_LOG_ERROR, "Failed allocating output stream\n");
               return AVERROR_UNKNOWN;
           }

           in_stream = ifmt_ctx->streams[i];
           dec_ctx = stream_ctx[i].dec_ctx;

           if (dec_ctx->codec_type == AVMEDIA_TYPE_VIDEO) {
               /* in this example, we choose transcoding to same codec */
               encoder = avcodec_find_encoder(dec_ctx->codec_id);
               if (!encoder) {
                   av_log(NULL, AV_LOG_FATAL, "Necessary encoder not found\n");
                   return AVERROR_INVALIDDATA;
               }
               enc_ctx = avcodec_alloc_context3(encoder);
               if (!enc_ctx) {
                   av_log(NULL, AV_LOG_FATAL, "Failed to allocate the encoder context\n");
                   return AVERROR(ENOMEM);
               }

               /* In this example, we transcode to same properties (picture size,
               * sample rate etc.). These properties can be changed for output
               * streams easily using filters */
               enc_ctx->height = dec_ctx->height;
               enc_ctx->width = dec_ctx->width;
               enc_ctx->sample_aspect_ratio = dec_ctx->sample_aspect_ratio;
               /* take first format from list of supported formats */
               if (encoder->pix_fmts)
                   enc_ctx->pix_fmt = encoder->pix_fmts[0];
               else
                   enc_ctx->pix_fmt = dec_ctx->pix_fmt;

               /* video time_base can be set to whatever is handy and supported by encoder */
               //enc_ctx->time_base = av_inv_q(dec_ctx->framerate);
               enc_ctx->time_base = dec_ctx->time_base;


               /* Third parameter can be used to pass settings to encoder */
               ret = avcodec_open2(enc_ctx, encoder, NULL);
               if (ret &lt; 0) {
                   av_log(NULL, AV_LOG_ERROR, "Cannot open video encoder for stream #%u\n", i);
                   return ret;
               }
               ret = avcodec_parameters_from_context(out_stream->codecpar, enc_ctx);
               if (ret &lt; 0) {
                   av_log(NULL, AV_LOG_ERROR, "Failed to copy encoder parameters to output stream #%u\n", i);
                   return ret;
               }
               if (ofmt_ctx->oformat->flags &amp; AVFMT_GLOBALHEADER)
                   enc_ctx->flags |= AV_CODEC_FLAG_GLOBAL_HEADER;

               out_stream->time_base = enc_ctx->time_base;
               stream_ctx[i].enc_ctx = enc_ctx;
           }
           else if (dec_ctx->codec_type == AVMEDIA_TYPE_UNKNOWN) {
               av_log(NULL, AV_LOG_FATAL, "Elementary stream #%d is of unknown type, cannot proceed\n", i);
               return AVERROR_INVALIDDATA;
           }
           else {
               /* if this stream must be remuxed */
               ret = avcodec_parameters_copy(out_stream->codecpar, in_stream->codecpar);
               if (ret &lt; 0) {
                   av_log(NULL, AV_LOG_ERROR, "Copying parameters for stream #%u failed\n", i);
                   return ret;
               }
               out_stream->time_base = in_stream->time_base;
           }

       }
       av_dump_format(ofmt_ctx, 0, filename, 1);

       if (!(ofmt_ctx->oformat->flags &amp; AVFMT_NOFILE)) {
           ret = avio_open(&amp;ofmt_ctx->pb, filename, AVIO_FLAG_WRITE);
           if (ret &lt; 0) {
               av_log(NULL, AV_LOG_ERROR, "Could not open output file '%s'", filename);
               return ret;
           }
       }

       /* init muxer, write output file header */
       ret = avformat_write_header(ofmt_ctx, NULL);
       if (ret &lt; 0) {
           av_log(NULL, AV_LOG_ERROR, "Error occurred when opening output file\n");
           return ret;
       }

       return 0;
    }

    static int init_filter(FilteringContext* fctx, AVCodecContext *dec_ctx,
       AVCodecContext *enc_ctx, const char *filter_spec)
    {
       char args[512];
       int ret = 0;
       AVFilter *buffersrc = NULL;
       AVFilter *buffersink = NULL;
       AVFilterContext *buffersrc_ctx = NULL;
       AVFilterContext *buffersink_ctx = NULL;
       AVFilterInOut *outputs = avfilter_inout_alloc();
       AVFilterInOut *inputs = avfilter_inout_alloc();
       AVFilterGraph *filter_graph = avfilter_graph_alloc();

       if (!outputs || !inputs || !filter_graph) {
           ret = AVERROR(ENOMEM);
           goto end;
       }

       if (dec_ctx->codec_type == AVMEDIA_TYPE_VIDEO) {
           buffersrc = avfilter_get_by_name("buffer");
           buffersink = avfilter_get_by_name("buffersink");
           if (!buffersrc || !buffersink) {
               av_log(NULL, AV_LOG_ERROR, "filtering source or sink element not found\n");
               ret = AVERROR_UNKNOWN;
               goto end;
           }

           snprintf(args, sizeof(args),
               "video_size=%dx%d:pix_fmt=%d:time_base=%d/%d:pixel_aspect=%d/%d",
               dec_ctx->width, dec_ctx->height, dec_ctx->pix_fmt,
               dec_ctx->time_base.num, dec_ctx->time_base.den,
               dec_ctx->sample_aspect_ratio.num,
               dec_ctx->sample_aspect_ratio.den);

           ret = avfilter_graph_create_filter(&amp;buffersrc_ctx, buffersrc, "in",
               args, NULL, filter_graph);
           if (ret &lt; 0) {
               av_log(NULL, AV_LOG_ERROR, "Cannot create buffer source\n");
               goto end;
           }

           ret = avfilter_graph_create_filter(&amp;buffersink_ctx, buffersink, "out",
               NULL, NULL, filter_graph);
           if (ret &lt; 0) {
               av_log(NULL, AV_LOG_ERROR, "Cannot create buffer sink\n");
               goto end;
           }

           ret = av_opt_set_bin(buffersink_ctx, "pix_fmts",
               (uint8_t*)&amp;enc_ctx->pix_fmt, sizeof(enc_ctx->pix_fmt),
               AV_OPT_SEARCH_CHILDREN);
           if (ret &lt; 0) {
               av_log(NULL, AV_LOG_ERROR, "Cannot set output pixel format\n");
               goto end;
           }
       }
       else {
           ret = AVERROR_UNKNOWN;
           goto end;
       }

       /* Endpoints for the filter graph. */
       outputs->name = av_strdup("in");
       outputs->filter_ctx = buffersrc_ctx;
       outputs->pad_idx = 0;
       outputs->next = NULL;

       inputs->name = av_strdup("out");
       inputs->filter_ctx = buffersink_ctx;
       inputs->pad_idx = 0;
       inputs->next = NULL;

       if (!outputs->name || !inputs->name) {
           ret = AVERROR(ENOMEM);
           goto end;
       }

       if ((ret = avfilter_graph_parse_ptr(filter_graph, filter_spec,
           &amp;inputs, &amp;outputs, NULL)) &lt; 0)
           goto end;

       if ((ret = avfilter_graph_config(filter_graph, NULL)) &lt; 0)
           goto end;

       /* Fill FilteringContext */
       fctx->buffersrc_ctx = buffersrc_ctx;
       fctx->buffersink_ctx = buffersink_ctx;
       fctx->filter_graph = filter_graph;

    end:
       avfilter_inout_free(&amp;inputs);
       avfilter_inout_free(&amp;outputs);

       return ret;
    }

    static int init_filters(const int videoStreamIndex)
    {
       const char *filter_spec;
       unsigned int i;
       int ret;
       filter_ctx = (FilteringContext*)av_malloc_array(ifmt_ctx->nb_streams, sizeof(*filter_ctx));
       if (!filter_ctx)
           return AVERROR(ENOMEM);

       for (i = 0; i &lt; ifmt_ctx->nb_streams; i++) {

           // Just video
           if (i != videoStreamIndex)
               continue;

           filter_ctx[i].buffersrc_ctx = NULL;
           filter_ctx[i].buffersink_ctx = NULL;
           filter_ctx[i].filter_graph = NULL;
           if (!(ifmt_ctx->streams[i]->codecpar->codec_type == AVMEDIA_TYPE_AUDIO
               || ifmt_ctx->streams[i]->codecpar->codec_type == AVMEDIA_TYPE_VIDEO))
               continue;

           filter_spec = "null"; /* passthrough (dummy) filter for video */
           //filter_spec = "scale=w=iw/2:-1";
           // filter_spec = "drawtext=fontfile=FreeSerif.ttf: text='%{localtime}': x=w-text_w: y=0: fontsize=24: fontcolor=yellow@1.0: box=1: boxcolor=red@1.0";
           // filter_spec = "drawtext=fontfile=FreeSerif.ttf :text='test': x=w-text_w: y=text_h: fontsize=24: fontcolor=yellow@1.0: box=1: boxcolor=red@1.0";

           ret = init_filter(&amp;filter_ctx[i], stream_ctx[i].dec_ctx,
               stream_ctx[i].enc_ctx, filter_spec);
           if (ret)
               return ret;
       }
       return 0;
    }

    static int encode_write_frame(AVFrame *filt_frame, unsigned int stream_index, int *got_frame, const int videoStreamIndex) {

       // Just video
       if (stream_index != videoStreamIndex)
           return 0;

       int ret;
       int got_frame_local;
       AVPacket enc_pkt;
       int(*enc_func)(AVCodecContext *, AVPacket *, const AVFrame *, int *) =
           (ifmt_ctx->streams[stream_index]->codecpar->codec_type ==
               AVMEDIA_TYPE_VIDEO) ? avcodec_encode_video2 : avcodec_encode_audio2;

       if (!got_frame)
           got_frame = &amp;got_frame_local;

       // av_log(NULL, AV_LOG_INFO, "Encoding frame\n");
       /* encode filtered frame */
       enc_pkt.data = NULL;
       enc_pkt.size = 0;
       av_init_packet(&amp;enc_pkt);

       ret = enc_func(stream_ctx[stream_index].enc_ctx, &amp;enc_pkt,
           filt_frame, got_frame);

       av_frame_free(&amp;filt_frame);
       if (ret &lt; 0)
           return ret;
       if (!(*got_frame))
           return 0;

       /* prepare packet for muxing */
       /*enc_pkt.stream_index = stream_index;
       av_packet_rescale_ts(&amp;enc_pkt, stream_ctx[stream_index].enc_ctx->time_base, ofmt_ctx->streams[stream_index]->time_base);*/
       enc_pkt.stream_index = 0;
       av_packet_rescale_ts(&amp;enc_pkt, stream_ctx[stream_index].enc_ctx->time_base, ofmt_ctx->streams[0]->time_base);

       av_log(NULL, AV_LOG_DEBUG, "Muxing frame\n");
       /* mux encoded frame */
       ret = av_interleaved_write_frame(ofmt_ctx, &amp;enc_pkt);
       return ret;
    }

    static int filter_encode_write_frame(AVFrame *frame, unsigned int stream_index, const int videoStreamIndex)
    {
       // Just video, all else crashes
       if (stream_index != videoStreamIndex)
           return 0;

       int ret;
       AVFrame *filt_frame;

       // av_log(NULL, AV_LOG_INFO, "Pushing decoded frame to filters\n");
       /* push the decoded frame into the filtergraph */
       ret = av_buffersrc_add_frame_flags(filter_ctx[stream_index].buffersrc_ctx,
           frame, 0);
       if (ret &lt; 0) {
           av_log(NULL, AV_LOG_ERROR, "Error while feeding the filtergraph\n");
           return ret;
       }

       /* pull filtered frames from the filtergraph */
       while (1) {
           filt_frame = av_frame_alloc();
           if (!filt_frame) {
               ret = AVERROR(ENOMEM);
               break;
           }
           // av_log(NULL, AV_LOG_INFO, "Pulling filtered frame from filters\n");
           ret = av_buffersink_get_frame(filter_ctx[stream_index].buffersink_ctx,
               filt_frame);
           if (ret &lt; 0) {
               /* if no more frames for output - returns AVERROR(EAGAIN)
               * if flushed and no more frames for output - returns AVERROR_EOF
               * rewrite retcode to 0 to show it as normal procedure completion
               */
               if (ret == AVERROR(EAGAIN) || ret == AVERROR_EOF)
                   ret = 0;
               av_frame_free(&amp;filt_frame);
               break;
           }

           filt_frame->pict_type = AV_PICTURE_TYPE_NONE;
           ret = encode_write_frame(filt_frame, stream_index, NULL, videoStreamIndex);
           if (ret &lt; 0)
               break;
       }

       return ret;
    }

    static int flush_encoder(unsigned int stream_index, const int videoStreamIndex)
    {
       int ret;
       int got_frame;

       // Just video
       if (stream_index != videoStreamIndex)
           return 0;

       if (!(stream_ctx[stream_index].enc_ctx->codec->capabilities &amp;
           AV_CODEC_CAP_DELAY))
           return 0;

       while (1) {
           av_log(NULL, AV_LOG_INFO, "Flushing stream #%u encoder\n", stream_index);
           ret = encode_write_frame(NULL, stream_index, &amp;got_frame, videoStreamIndex);
           if (ret &lt; 0)
               break;
           if (!got_frame)
               return 0;
       }
       return ret;
    }


    #include <vector>

    int main(int argc, char **argv)
    {
       int ret;

       AVPacket packet;
       packet.data = NULL;
       packet.size = 0;

       AVFrame *frame = NULL;
       enum AVMediaType type;
       unsigned int stream_index;
       unsigned int i;
       int got_frame;
       int(*dec_func)(AVCodecContext *, AVFrame *, int *, const AVPacket *);


    #ifdef _DEBUG
       // Hardcoded arguments
       std::vector varguments;
       {
           varguments.push_back(argv[0]);

           // Source
           varguments.push_back("./big_buck_bunny_short.mp4 ");

           // Destination
           varguments.push_back("./big_buck_bunny_short-processed.mp4");
       }

       char** arguments = new char*[varguments.size()];
       for (unsigned int i = 0; i &lt; varguments.size(); i++)
       {
           arguments[i] = varguments[i];
       }
       argc = varguments.size();
       argv = arguments;
    #endif // _DEBUG


       if (argc != 3) {
           av_log(NULL, AV_LOG_ERROR, "Usage: %s <input file="file" /> <output file="file">\n", argv[0]);
           return 1;
       }

       av_register_all();
       avfilter_register_all();

       int videoStreamIndex = -1;
       if ((ret = open_input_file(argv[1], videoStreamIndex)) &lt; 0)
           goto end;
       if ((ret = open_output_file(argv[2], videoStreamIndex)) &lt; 0)
           goto end;
       if ((ret = init_filters(videoStreamIndex)) &lt; 0)
           goto end;

       // Stop after a couple of frames
       int framesToGet = 100;

       /* read all packets */
       //while (framesToGet--)
       while(1)
       {
           if ((ret = av_read_frame(ifmt_ctx, &amp;packet)) &lt; 0)
               break;
           stream_index = packet.stream_index;

           // I just need video
           if (stream_index != videoStreamIndex) {
               av_packet_unref(&amp;packet);
               continue;
           }

           type = ifmt_ctx->streams[packet.stream_index]->codecpar->codec_type;
           av_log(NULL, AV_LOG_DEBUG, "Demuxer gave frame of stream_index %u\n",
               stream_index);

           if (filter_ctx[stream_index].filter_graph) {
               av_log(NULL, AV_LOG_DEBUG, "Going to reencode&amp;filter the frame\n");
               frame = av_frame_alloc();
               if (!frame) {
                   ret = AVERROR(ENOMEM);
                   break;
               }
               av_packet_rescale_ts(&amp;packet,
                   ifmt_ctx->streams[stream_index]->time_base,
                   stream_ctx[stream_index].dec_ctx->time_base);
               dec_func = (type == AVMEDIA_TYPE_VIDEO) ? avcodec_decode_video2 :
                   avcodec_decode_audio4;
               ret = dec_func(stream_ctx[stream_index].dec_ctx, frame,
                   &amp;got_frame, &amp;packet);
               if (ret &lt; 0) {
                   av_frame_free(&amp;frame);
                   av_log(NULL, AV_LOG_ERROR, "Decoding failed\n");
                   break;
               }

               if (got_frame) {
                   frame->pts = frame->best_effort_timestamp;
                   ret = filter_encode_write_frame(frame, stream_index, videoStreamIndex);
                   av_frame_free(&amp;frame);
                   if (ret &lt; 0)
                       goto end;
               }
               else {
                   av_frame_free(&amp;frame);
               }
           }
           else {
               /* remux this frame without reencoding */
               av_packet_rescale_ts(&amp;packet,
                   ifmt_ctx->streams[stream_index]->time_base,
                   ofmt_ctx->streams[stream_index]->time_base);

               ret = av_interleaved_write_frame(ofmt_ctx, &amp;packet);
               if (ret &lt; 0)
                   goto end;
           }
           av_packet_unref(&amp;packet);
       }

       /* flush filters and encoders */
       for (i = 0; i &lt; ifmt_ctx->nb_streams; i++) {
           /* flush filter */
           if (!filter_ctx[i].filter_graph)
               continue;
           ret = filter_encode_write_frame(NULL, i, videoStreamIndex);
           if (ret &lt; 0) {
               av_log(NULL, AV_LOG_ERROR, "Flushing filter failed\n");
               goto end;
           }

           /* flush encoder */
           ret = flush_encoder(i, videoStreamIndex);
           if (ret &lt; 0) {
               av_log(NULL, AV_LOG_ERROR, "Flushing encoder failed\n");
               goto end;
           }
       }

       av_write_trailer(ofmt_ctx);
    end:
       av_packet_unref(&amp;packet);
       av_frame_free(&amp;frame);
       for (i = 0; i &lt; ifmt_ctx->nb_streams; i++) {
           // Just video
           if (i != videoStreamIndex)
               continue;
           avcodec_free_context(&amp;stream_ctx[i].dec_ctx);
           if (ofmt_ctx &amp;&amp; ofmt_ctx->nb_streams > i &amp;&amp; ofmt_ctx->streams[i] &amp;&amp; stream_ctx[i].enc_ctx)
               avcodec_free_context(&amp;stream_ctx[i].enc_ctx);
           if (filter_ctx &amp;&amp; filter_ctx[i].filter_graph)
               avfilter_graph_free(&amp;filter_ctx[i].filter_graph);
       }
       av_free(filter_ctx);
       av_free(stream_ctx);
       avformat_close_input(&amp;ifmt_ctx);
       if (ofmt_ctx &amp;&amp; !(ofmt_ctx->oformat->flags &amp; AVFMT_NOFILE))
           avio_closep(&amp;ofmt_ctx->pb);
       avformat_free_context(ofmt_ctx);

       /*if (ret &lt; 0)
           av_log(NULL, AV_LOG_ERROR, "Error occurred: %s\n", av_err2str(ret));*/

       return ret ? 1 : 0;
    }
    </output></vector>
  • Measuring success for your SEO content

    20 mars 2020, par Jake Thornton — Uncategorized

    With over a billion searches every day in search engines, it’s hard to underestimate the importance of having your business present on page one (ideally in positions 1 – 3) ranking for the keywords that impact your sales and conversions.

    "In 2019, Google received nearly 2.3 trillion searches and on page one alone, the first five organic results accounted for 67.60% of all the clicks."

    So how is your business performing when it comes to ranking in the crucial top three spots of search for your most important keywords ?

    Accurately measuring the success of your content

    Once you’ve done your keyword research, created compelling content, optimised it to be search-friendly, and hit ‘publish’, you then need to accurately measure the success of your efforts.

    4 tips for measuring the success of your SEO content

    1. Create a custom segment for "Visitors from Search Engines only"

    By creating this custom segment, you’ll be able to analyse the behavioural patterns of the visitors who found your website through a search engine. 

    This way you can use many of Matomo’s powerful features (Visitors, Behaviour, Acquisition, Ecommerce, Goals etc.) focused entirely on search engine visitors only.

    Once you’ve created this segment, you can begin to see key metrics like which entry pages are responsible for referring visitors to your website. For example : Visit Behaviour – Entry Pages, this is a great way to analyse your most effective SEO pages.You may be surprised at what pages currently bring in the most traffic.

    As well as discovering which content resonates with your search audience, you will also be able to create more content focused on your targeted audience. Do this by learning which locations your search visitors are from, which device they use, what time of the day they visited your website and much more.

    >> Learn more about creating custom segments

    2. Website visits, time on site, pages per session, and bounce rate.

    “The top four ranking factors are website visits, time on site, pages per session, and bounce rate.”

    These four metrics set the benchmark for your SEO success.

    First, you need to get as many of the ‘right’ users to see your content. If you feel you’ve exhausted channels such as social media, email and possibly paid posts ; think about who your ideal audience is. Where are they likely to hang out online ? Are there community groups or forum sites that are interested in what you’re writing about ? 

    Whatever the case, putting yourself out there and getting more traffic to your website will help show search engines that people are interested in your website. As a result, they’ll likely rank you higher for that.

    When we say getting more of the ‘right’ users, we mean users who are generally interested in the topic/subject you’re writing about and interested in the work you do. 

    This is important for the next three metrics – increasing users time on your website, increasing the amount of pages your users explore on your website, and reducing the overall bounce rate for users who leave your website in a matter of seconds.

    To evaluate these metrics, go to Behaviour Pages in your Matomo and see how these metrics vary on previous posts or pages you’ve created. Which pages are already showing you the best results ? Why do they get the results ? Can you focus on creating more content like this ?

    Understanding what content is resonating with your users through these metrics is easy and is the starting point for measuring the success of your SEO content strategy.

    >> Learn more about the Behaviour feature

    3. Row Evolution

    The Row Evolution feature embedded within the Search Engine Keywords Performance plugin lets you see how your ranking positions have changed over time for your important keywords. It also lets you see how the incoming traffic, related to your keywords, has changed over time.

    This is valuable when measuring the changes you’ve made to your landing pages to see if it has a positive or negative effect on your ranking efforts. 

    This also lets you see how search engine algorithm changes affect your search rankings over time, and to see if the effects of these algorithm updates are temporary or long lasting.

    Row evolution allows you to report on keyword performance with ease. If you only check your insights once a week or once a fortnight, you’ll see how ranking positions for your important keywords have changed daily (or even weekly, monthly or yearly however you prefer.)

    >> Learn more about Row Evolution

    4. What results are you getting from the lesser known search engines ?

    "In 2019 (to date), Google accounted for just over 75% of all global desktop search traffic, followed by Bing at 9.97%, Baidu at 9.34%, and Yahoo at 2.77%."

    For most of us, we want to be ranking in the top three spots in Google Search because that’s where the majority of search users are. However, don’t shy away from opportunities you could be missing with lesser known search engines.

    If you sell a product aimed at 55-65 year olds who use a PC computer, chances are they are using Bing. If you have customers in China the majority will be using Baidu, or in our case at Matomo, many of our loyal users use a privacy-friendly search engine like DuckDuckGo or Qwant.

    Some of your ideal customers might be finding you through these alternative search engines, so be sure to measure the impact that these referrals may have on your conversions.

    Strategically including important keywords that impact your business

    While search is an important acquisition channel for most businesses, it’s also one of the most competitive.

    We recommend analysing your keyword and content performance regularly and alter content that isn’t performing as well as you’d like. You need to continually learn from the content that is successful, and focus on creating more content like this. 

    The final thing to remember with search keyword performance is to be patient. If you have had little success in the past with attracting customers through search, it can take time to build this reputation with search engines.