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  • MediaSPIP v0.2

    21 juin 2013, par

    MediaSPIP 0.2 est la première version de MediaSPIP stable.
    Sa date de sortie officielle est le 21 juin 2013 et est annoncée ici.
    Le fichier zip ici présent contient uniquement les sources de MediaSPIP en version standalone.
    Comme pour la version précédente, il est nécessaire d’installer manuellement l’ensemble des dépendances logicielles sur le serveur.
    Si vous souhaitez utiliser cette archive pour une installation en mode ferme, il vous faudra également procéder à d’autres modifications (...)

  • Mise à disposition des fichiers

    14 avril 2011, par

    Par défaut, lors de son initialisation, MediaSPIP ne permet pas aux visiteurs de télécharger les fichiers qu’ils soient originaux ou le résultat de leur transformation ou encodage. Il permet uniquement de les visualiser.
    Cependant, il est possible et facile d’autoriser les visiteurs à avoir accès à ces documents et ce sous différentes formes.
    Tout cela se passe dans la page de configuration du squelette. Il vous faut aller dans l’espace d’administration du canal, et choisir dans la navigation (...)

  • MediaSPIP version 0.1 Beta

    16 avril 2011, par

    MediaSPIP 0.1 beta est la première version de MediaSPIP décrétée comme "utilisable".
    Le fichier zip ici présent contient uniquement les sources de MediaSPIP en version standalone.
    Pour avoir une installation fonctionnelle, il est nécessaire d’installer manuellement l’ensemble des dépendances logicielles sur le serveur.
    Si vous souhaitez utiliser cette archive pour une installation en mode ferme, il vous faudra également procéder à d’autres modifications (...)

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  • Privacy in Business : What Is It and Why Is It Important ?

    13 juillet 2022, par Erin — Privacy

    Privacy concerns loom large among consumers. Yet, businesses remain reluctant to change the old ways of doing things until they become an operational nuisance. 

    More and more businesses are slowly starting to feel the pressure to incorporate privacy best practices. But what exactly does privacy mean in business ? And why is it important for businesses to protect users’ privacy ? 

    In this blog, we’ll answer all of these questions and more. 

    What is Privacy in Business ?

    In the corporate world, privacy stands for the business decision to use collected consumer data in a safe, secure and compliant way. 

    Companies with a privacy-centred culture : 

    • Get explicit user consent to tracking, opt-ins and data sharing 
    • Collect strictly necessary data in compliance with regulations 
    • Ask for permissions to collect, process and store sensitive data 
    • Provide transparent explanations about data operationalisation and usage 
    • Have mechanisms for data collection opt-outs and data removal requests 
    • Implement security controls for storing collected data and limit access permissions to it 

    In other words : They treat consumers’ data with utmost integrity and security – and provide reassurances of ethical data usage. 

    What Are the Ethical Business Issues Related to Privacy ?

    Consumer data analytics has been around for decades. But digital technologies – ubiquitous connectivity, social media networks, data science and machine learning – increased the magnitude and sophistication of customer profiling.

    Big Tech companies like Google and Facebook, among others, capture millions of data points about users. These include general demographics data like “age” or “gender”, as well as more granular insights such as “income”, “past browsing history” or “recently visited geo-locations”. 

    When combined, such personally identifiable information (PII) can be used to approximate the user’s exact address, frequently purchased goods, political beliefs or past medical conditions. Then such information is shared with third parties such as advertisers. 

    That’s when ethical issues arise. 

    The Cambridge Analytica data scandal is a prime example of consumer data that was unethically exploited. 

    Over the years, Google also faced a series of regulatory issues surrounding consumer privacy breaches :

    • In 2021, a Google Chrome browser update put some 2.6 billion users at risk of “surveillance, manipulation and abuse” by providing third parties with data on device usage. 
    • The same year, Google was taken to court for failing to provide full disclosures on tracking performed in Google Chrome incognito mode. A $5 billion lawsuit is still pending.
    • As of 2022, Google Analytics 4 is considered GDPR non-compliant and was branded “illegal” by several European countries. 

    If you are curious, learn more about Google Analytics privacy issues

    The bigger issue ? Big Tech companies make the businesses that use their technologies (unknowingly) complicit in consumer data violations.

    In 2022, the Belgian data regulator found the official IAB Europe framework for user consent gathering in breach of GDPR. The framework was used by all major AdTech platforms to issue pop-ups for user consent to tracking. Now ad platforms must delete all data gathered through these. Biggest advertisers such as Procter & Gamble, Unilever, IBM and Mastercard among others, also received a notice about data removal and a regulatory warning on further repercussions if they fail to comply. 

    Big Tech firms have given brands unprecedented access to granular consumer data. Unrestricted access, however, also opened the door to data abuse and unethical use. 

    Examples of Unethical Data Usage by Businesses 

    • Data hoarding means excessively harvesting all available consumer data because a possibility to do so exists, often using murky consent mechanisms. Yet, 85% of collected Big Data is either dark or redundant, obsolete or trivial (ROT).
    • Invasive personalisation based on sensitive user information (or second-guesses), like a recent US marketing campaign, congratulating women on pregnancy (even if they weren’t expecting). Overall, 75% of consumers find most forms of personalisation somewhat creepy. 22% also said they’d leave for another brand due to creepy experiences.
    • Hyper-targeted advertising campaigns based on data consumers would prefer not to share. A recent investigation found that advertising platforms often assign sensitive labels to users (as part of their ad profiles), indicative of their religion, mental issues, history with abuse and so on. This allows advertisers to target such consumers with dubious ads. 

    Ultimately, excessive data collection, paired with poor data protection in business settings, results in major data breaches and costly damage control. Given that cyber attacks are on the rise, every business is vulnerable. 

    Why Should a Business Be Concerned About Protecting the Privacy of Its Customers ?

    Businesses must prioritise customer privacy because that’s what is expected of them. Globally, 89% of consumers say they care about their privacy. 

    As frequent stories about unethical data usage, excessive tracking and data breaches surface online, even more grow more concerned about protecting their data. Many publicly urge companies to take action. Others curtail their relationships with brands privately. 

    On average, 45% of consumers feel uncomfortable about sharing personal data. According to KPMG, 78% of American consumers have fears about the amount of data being collected. 40% of them also don’t trust companies to use their data ethically. Among Europeans, 41% are unwilling to share any personal data with businesses. 

    Because the demand for online privacy is rising, progressive companies now treat privacy as a competitive advantage. 

    For example, the encrypted messaging app Signal gained over 42 million active users in a year because it offers better data security and privacy protection. 

    ProtonMail, a privacy-centred email client, also amassed a 50 million user base in several years thanks to a “fundamentally stronger definition of privacy”.

    The growth of privacy-mindful businesses speaks volumes. And even more good things happen to privacy-mindful businesses : 

    • Higher consumer trust and loyalty 
    • Improved attractiveness to investors
    • Less complex compliance
    • Minimum cybersecurity exposure 
    • Better agility and innovation

    It’s time to start pursuing them ! Learn how to embed privacy and security into your operations.

  • Build Opencv3.1 with ffmpeg

    10 mai 2018, par batuman

    I tried to build Opencv3.1 at Ubuntu16.04 with ffmpeg.
    I follow the instructions how to install ffmpeg at here.

    According to this discussion ,I checked.

    >> mediainfo ~/Desktop/grb_2.mp4
    General
    Complete name                            : /home/nyan/Desktop/grb_2.mp4
    Format                                   : MPEG-4
    Format profile                           : Base Media
    Codec ID                                 : isom (isom/iso2/avc1/mp41)
    File size                                : 445 KiB
    Duration                                 : 27s 862ms
    Overall bit rate                         : 131 Kbps
    Encoded date                             : UTC 1904-01-01 00:00:00
    Tagged date                              : UTC 1904-01-01 00:00:00
    Writing application                      : Lavf57.66.105

    Video
    ID                                       : 1
    Format                                   : AVC
    Format/Info                              : Advanced Video Codec
    Format profile                           : High@L3
    Format settings, CABAC                   : Yes
    Format settings, ReFrames                : 4 frames
    Codec ID                                 : avc1
    Codec ID/Info                            : Advanced Video Coding
    Duration                                 : 27s 862ms
    Bit rate                                 : 128 Kbps
    Width                                    : 720 pixels
    Height                                   : 480 pixels
    Display aspect ratio                     : 4:3
    Original display aspect ratio            : 4:3
    Frame rate mode                          : Constant
    Frame rate                               : 29.970 (30000/1001) fps
    Standard                                 : NTSC
    Color space                              : YUV
    Chroma subsampling                       : 4:2:0
    Bit depth                                : 8 bits
    Scan type                                : Progressive
    Bits/(Pixel*Frame)                       : 0.012
    Stream size                              : 435 KiB (98%)
    Writing library                          : x264 core 148
    Encoding settings                        : cabac=1 / ref=3 / deblock=1:0:0 / analyse=0x3:0x113 / me=hex / subme=7 / psy=1 / psy_rd=1.00:0.00 / mixed_ref=1 / me_range=16 / chroma_me=1 / trellis=1 / 8x8dct=1 / cqm=0 / deadzone=21,11 / fast_pskip=1 / chroma_qp_offset=-2 / threads=12 / lookahead_threads=2 / sliced_threads=0 / nr=0 / decimate=1 / interlaced=0 / bluray_compat=0 / constrained_intra=0 / bframes=3 / b_pyramid=2 / b_adapt=1 / b_bias=0 / direct=1 / weightb=1 / open_gop=0 / weightp=2 / keyint=250 / keyint_min=25 / scenecut=40 / intra_refresh=0 / rc_lookahead=40 / rc=crf / mbtree=1 / crf=23.0 / qcomp=0.60 / qpmin=0 / qpmax=69 / qpstep=4 / ip_ratio=1.40 / aq=1:1.00
    Encoded date                             : UTC 1904-01-01 00:00:00
    Tagged date                              : UTC 1904-01-01 00:00:00





    ffmpeg -codecs | grep -i avc
    ffmpeg version N-90982-gb995ec0 Copyright (c) 2000-2018 the FFmpeg developers
     built with gcc 5.4.0 (Ubuntu 5.4.0-6ubuntu1~16.04.9) 20160609
     configuration: --prefix=/home/nyan/ffmpeg_build --enable-shared --extra-cflags=-I/home/nyan/ffmpeg_build/include --extra-ldflags=-L/home/nyan/ffmpeg_build/lib --extra-libs='-lpthread -lm' --bindir=/home/nyan/bin --enable-gpl --enable-libass --enable-libfdk-aac --enable-libfreetype --enable-libmp3lame --enable-libopus --enable-libtheora --enable-libvorbis --enable-libvpx --enable-libx264 --enable-libx265 --enable-nonfree
     libavutil      56. 18.100 / 56. 18.100
     libavcodec     58. 19.100 / 58. 19.100
     libavformat    58. 13.101 / 58. 13.101
     libavdevice    58.  4.100 / 58.  4.100
     libavfilter     7. 21.100 /  7. 21.100
     libswscale      5.  2.100 /  5.  2.100
     libswresample   3.  2.100 /  3.  2.100
     libpostproc    55.  2.100 / 55.  2.100
    DEV.LS h264                 H.264 / AVC / MPEG-4 AVC / MPEG-4 part 10 (decoders: h264 h264_v4l2m2m ) (encoders: libx264 libx264rgb h264_v4l2m2m h264_vaapi )
    D.A.L. avc                  On2 Audio for Video Codec (decoders: on2avc )

    So my ffmpeg installation is ok.

    When I cmake to my Opencv, I have set up to ffmpeg as

    enter image description here

    But when I make to compile, I have error as

    make[2]: *** No rule to make target '/home/nyan/ffmpeg_build/lib/libavresample.a', needed by 'lib/libopencv_videoio.so.3.1.0'.  Stop.
    CMakeFiles/Makefile2:8709: recipe for target 'modules/videoio/CMakeFiles/opencv_videoio.dir/all' failed
    make[1]: *** [modules/videoio/CMakeFiles/opencv_videoio.dir/all] Error 2
    Makefile:160: recipe for target 'all' failed
    make: *** [all] Error 2

    How can I fix the problem ?

    I install libavresample manually and

    sudo apt-get install libavresample-dev
    [sudo] password for nyan:
    Reading package lists... Done
    Building dependency tree      
    Reading state information... Done
    libavresample-dev is already the newest version (7:2.8.14-0ubuntu0.16.04.1).

    It is newest version.

    EDIT:

    Actually libavresample at ffmpeg is deprecated already.
    So I tried to install Opencv3.4.1 higher version.
    Compile, build and installation are fine.
    But VideoCapture cap(0); does not read from the device.
    So I checked ffmpeg at Opencv3.4.1 installation as

    python -c "import cv2; print(cv2.getBuildInformation())" | grep -i ffmpeg

    FFMMPEG IS NO. So build with ffmpeg is not successful even though there was no error at build for Opencv3.4.1.

  • FFmpeg decoding subtitle (delphi) decoding resutl > 0 but values are zero/null

    27 janvier 2020, par coban
    while True do begin
    if vst.sub_q.size = 0
    then Continue;

    ret := mpl.packet_queue_get(vst.sub_q, pkt, 0);
    if(pkt.data = mpl.flush_pkt.data) then
    begin
     avcodec_flush_buffers(vst.sub_st.codec);
     continue;
    end;


    ret := avcodec_decode_subtitle2(vst.sub_codec_ctx, @subt, @got_sub, @pkt);
    if ret >= 0
    then begin
     if got_sub = 1
     then begin
       for i := 0 to subt.num_rects-1
       do begin
          s := subt.rects[i].text;
          if (subt.rects[i].text <> '') or
             (subt.rects[i].ass <> '')
          then  raise Exception.Create(s);
       end;

     end;
    end;

    av_packet_unref(pkt);
    end;

    I’m trying to build a video player using ffmpeg + sdl2 with Delphi. I found an example for this which did play video without problems but had problems with audio. Audio is solved by inspecting the ffplay example in c/c++ and translating the audio part to Delphi. I tried to translate complete ffplay but I had strange behavior on video part, it starts playing but after a few seconds audio is going on without problems, while video is getting green screen.

    Something is not going well while calling "decoder_decode_frame" function or "video_refresh" in case of video shomehow ?
    However, I am, so far, able to decode/play audio and video streams synchronized. At the moment picture/video quality can be better, but this is for later.

    The problem :
    I am using the code above to decode the subtitle stream.
    initializing and opening the codec is succeeds "avcodec_open2", queueing packets is succeeds, retrieving packet succeeds at the right moment when it should be displayed.

    "avcodec_decode_subtitle2" function succeeds, result is > 0, got_frame variable is assigned "1", avsubtitle(subt) is being assigned.
    I do not get any errors or warnings everyting seems to be correct except the value of avsubtitle.

    subt format is 1 this seems to be the problem, inspecting ffplay.c
    subt start_display_time is 0
    subt end_display_time is 0
    subt num_rects is 1

    rects ppAVSubtitleRect is assigned with values zero/nil
    rects type_ is subtitle_none

    Playing a *.mkv file, subtitle information from codec is
    codec name ’srt’
    codec long_name ’SubRip subtitle’


    If this type of subtitle is not supported, why can we decode it without any warnings or errors ?
    If it is possible to get the subtitle text, how can I achieve this ?


    AVSubtitle = record
    format: uint16_t;             (* 0 = graphics *)
    start_display_time: uint32_t; (* relative to packet pts, in ms *)
    end_display_time: uint32_t;   (* relative to packet pts, in ms *)
    num_rects: unsigned;
    rects: ppAVSubtitleRect;
    pts: int64_t; // < Same as packet pts, in AV_TIME_BASE
    end;

    AVSubtitleType = (                //
    SUBTITLE_NONE, SUBTITLE_BITMAP, // < A bitmap, pict will be set
    (*
     * Plain text, the text field must be set by the decoder and is
     * authoritative. ass and pict fields may contain approximations.
    *)
    SUBTITLE_TEXT,
    (*
     * Formatted text, the ass field must be set by the decoder and is
     * authoritative. pict and text fields may contain approximations.
    *)
    SUBTITLE_ASS);

    AVSubtitleRect = record
     x: int;         // < top left corner  of pict, undefined when pict is not set
     y: int;         // < top left corner  of pict, undefined when pict is not set
     w: int;         // < width            of pict, undefined when pict is not set
     h: int;         // < height           of pict, undefined when pict is not set
     nb_colors: int; // < number of colors in pict, undefined when pict is not set

    {$IFDEF FF_API_AVPICTURE}
    (*
     * @deprecated unused
    *)
    // attribute_deprecated
    pict: AVPicture deprecated;
    {$ENDIF}
    (*
     * data+linesize for the bitmap of this subtitle.
     * Can be set for text/ass as well once they are rendered.
    *)
    data: puint8_t_array_4;
    linesize: Tint_array_4;

    _type: AVSubtitleType;

    text: pAnsiChar; // < 0 terminated plain UTF-8 text

    (*
     * 0 terminated ASS/SSA compatible event line.
     * The presentation of this is unaffected by the other values in this
     * struct.
    *)
    ass: pAnsiChar;

    flags: int;
    end;

    -----------edit----------------------

    SetLength(buf, 0);
    for i := 0 to pkt.size-1
    do begin
     Insert(pkt.data[i], buf, length(buf));
    end;

    s := TEncoding.UTF8.GetString(buf);

    It seems that in this case the text is stored in pkt.data, I don’t think this is the right way to get the subtitle text but I wonder why avsubtitle doesn’t get the values. avpacket values seem like, (pts, dts, duration) etc, to be correct.
    If I should use such construction to get the subtitle (text)value, how can I detect if it is utf8 encoded or how to determine the encoding ?
    There are more questions to be answered like, the position of the subtitle. The bad thing about ffmpeg is it’s almost impossible to get answers.

    ------------------edi2----------------------------------
    Ok how I am solving this, is creating in memory a png image with transparency and writing text over it, converting the image to PAVRAME and show at the given pts time + duration. For the positioning is chosen horizontal center for each line and vertically the bottom minus X pixels. Looks like it’s working so far.

    Next ; the formatting of the text, like bold italic etc. Can anybody give a hint if there is a quick solution(function/method/example), I will try to create one, but a quick solution is welcome. As long as there is no nested formatting is used, it doesn’t sound tricky, but I’ve read that nested formatting can be used.

    Should it be that this(formatted text) the reason is why ffmpeg is not assigning any values to avsubtitle ?