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• Anomalie #3814 : Onglet {Mes articles} erroné en SPIP3.0

  9 août 2016, par Olivier Dutertre

  J’ai effectivement un ensemble de plugins installés, mais j’ai déja pu
  évacuer agenda et inscription 2.5 comme source puisqu’un autre
  internaute à testé avec ces deux plugins et ne reproduis pas.

  Le 09/08/2016 21:01, redmine@spip.org a écrit :

  La demande #3814 a été mise à jour par Pierre KUHN.

  Bonsoir,

  Tu utilises des plugins précis pour avoir ce problème ?

  ---

  Anomalie #3814 : Onglet Mes articles erroné en SPIP3.0
  <https://core.spip.net/issues/3814#change-11946>

  • Auteur : Olivier Dutertre
  • Statut : Nouveau
  • Priorité : Normal
  • Assigné à :
  • Catégorie : base de données
  • Version cible : 3.0
  • Resolution :
  • Navigateur :

  Je rencontre le soucis avec SPIP 3.0.22 reproduis sur deux versions du
  même site (prod et dev). Je n’ai pas eu de réponse sur la liste.
  J’ignore si ici est le bon endroit pour signaler ce genre de problème,
  alors merci de votre bienveillance.

  Dans la partie privée, l’onglet /mes articles/ de la page /articles/
  affiche des information incorrectes, c’est à dire des article qui ne
  sont pas forcément de l’auteur passé en paramètre.

  En explorant avec le mode debug, voila ce que j’ai découvert :

  la boucle telle que prévue initialement est :

  Elle donne le code suivant :

  SELECT articles.id_article, 0 as points, ’’, articles.titre, articles.statut, articles.id_rubrique, articles.titre AS titre_rang, articles.lang, articles.date, articles.id_rubrique, articles.id_article
  FROM info_articles AS `articles`
  INNER JOIN info_evenements AS L2 ON ( L2.id_article = articles.id_article )
  WHERE (L2.id_auteur = 3)
  AND ((articles.statut IN (’prepa’,’publie’,’refuse’,’prepa’)))
  GROUP BY articles.id_article
  ORDER BY articles.date DESC, articles.titre

  Je ne comprends pas la raison du recours à la table événements. et j’y
  vois une raison des résultats aberrant de la boucle

  Si par contre Je modifie la boucle avec une jointure :

  auteurs_liens)id_article ?id_rubrique ?id_mot ?id_auteur ?where ?statut ?recherche ?tri #ENVpar,date,#GETdefaut_tripar titrepagination #ENVnb,10 !lang_select>

  Cela me donne un code plus encourageant :

  SELECT articles.id_article, 0 as points, ’’, articles.titre, articles.statut, articles.id_rubrique, articles.titre AS titre_rang, articles.lang, articles.date, articles.id_rubrique, articles.id_article
  FROM info_articles AS `articles`
  INNER JOIN info_auteurs_liens AS L2 ON ( L2.id_objet = articles.id_article AND L2.objet=’article’)
  WHERE (L2.id_auteur = 3)
  AND ((articles.statut IN (’prepa’,’publie’,’refuse’,’prepa’)))
  GROUP BY articles.id_article
  ORDER BY articles.date DESC, articles.titre

  et surtout le résultat est conforme à mes attentes.

  Quelqu’un pourra-t’il éclaircir la raison de ce mystère ?

  ---

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• Best intra-frame codec for editing ? Having color issues with DNxHR and serious sync issues with Prores

  23 janvier 2020, par Raulo1985

  I have a couple of questions regarding intra-frame codecs for editing purposes (in Premiere Pro).

  A LITTLE CONTEXT :

  I ripped a HDR movie to a MP4 container some months ago, using H.264 as codec (high 10, level 5, UHD, YUV, subsampling 4:2:0). The video looks great, as it should. Now I want to edit a trailer for that movie (I edit in Adobe Premiere Pro, current version), and for fast playback I need to work with proxies or transcode the source file to an intra-frame non long GOP file and use it as the source file (hopefully as lossless as that transcoding step can be). I tried for several days to transcode the source file to DNxHR 444 10 bits (using FFmpeg and then Adobe Media Encoder), but the result was always a video with the colors messed up (sometimes very washed out, sometimes over saturated).

  FFprobe of the resulting DNxHR file said that the color space was BT709 (source file is obviously BT2020), and I don’t know why. The transcoding involved upsampling since the source file is 4:2:0 and DNxHR doesn’t support it, but I tried upsampling to 4:4:4 and also to 4:2:2, and both of those files looked exactly the same to me, and very different from the original footage (so, I don’t think upsampling is the cause of the color issue, but maybe the apparent color space change or something wrong with the metadata). The results were the same when transcoding with Adobe Media Encoder. Anyway, I seem to have given up transcoding to DNxHR and use it as the source file, unless someone has an idea of what’s causing this problem. I could have worked with the source file for exporting and DNxHR LB for proxies, but there were sync issues (between source file and proxy) that defeated all purposes while editing. Prores is out of the picture, sync issues were worse (several seconds of delay).

  For the record, the command used that didn’t work as expected (color wise) is :

  ffmpeg -channel_layout 63 -i input.mkv -map 0:0 -c:v dnxhd -vf "scale=in_range=limited:out_range=full" -color_range 2 -profile:v dnxhr_444 -pix_fmt yuv444p10le -acodec pcm_s24le -ar 48000 -ac 6 -channel_layout 63 -map 0:2 -hide_banner output.mxf

  I also tried without the commands "scale=in_range=limited:out_range=full" and "-color_range 2", with same results. Always used FFmpeg latest version, and I’m working in Windows 10 Pro, latest drivers and latest Klite codec pack. Video files were compared with Mediainfo, FFprobe, and visually with VLC.

  Well, like I said, I’m giving up using DNxHR as the source file for my project (it would have been ideal since it doesn’t have sync issues with the DNxHR proxies, and file size is not a problem for me). A user here at the forums suggested transcoding and use H.264 intra-frame as source file, which I didn’t know was an option (I didn’t know H.264 was capable of intra-frame, my bad). I’m aware that one should avoid unnecesary transcoding steps, but I can’t work with a H.264 UHD HDR source file (ultra slow playback), and the sync issues with proxies, no matter the codec, make it impossible to make accurate cuts.
  So, bottom line, I need to find a way to fix the color issue when transcoding to DNxHR, or try with an inter-frame codec that’s not DNxHR and that’s capable of preserving all the HDR info (and then see if it doesn’t have sync issues. I’m assuming that those may dissapear when using intra-frame for both source file and proxies).

  NOTE : When importing the DNxHR 444 file to Premiere Pro and looking at the Lumetri scopes tab, you can tell that the colors are clipped at 100 nits, like a regular SDR video. So apparently the color space was really reduced to BT709, and I don’t know why. The H.264 source file behaves as expected, with colors going past 100 nits.

  MY QUESTIONS :

  1) Is H.264 intra-frame a good format for editing with a good playback performance ?

  2) If H.264 intra-frame is a good option, what would be the advantages of the DNxHR codec (or Prores) over it for editing purposes ? Everybody suggests DNxHD/DNxHR or Prores as intermediate codecs, but if intra-frame H.264 has the same advantages for editing and supports HDR, what would be the reason to choose another codec like DNxHR ?

  3) Any ideas on what could be the cause of the colors not transcoding correctly from the H.264 source file to the DNxHR 444 10 bits one ? The command looks ok to me, but FFprobe output says the DNxHR video is BT709, while with the source file it says BT2020. Like I said, apparently there’s something wrong with the transcoding process regarding metadata or color space.

  4) I haven’t tried to transcode the source file to a DNxHR 444 10 bits video file, but in a MOV container. I don’t know how this works internally, but maybe the color issue has something to do with the container metadata or something. I may try this if there’s not another suggestion (transcoding this kind of files, as you know, takes time, so I’ll wait for some ideas first).

  NOTE : I tried to transcode the source file in the same way (DNxHR 444, 10 bits, etc) with Adobe Media Encoder 2020 and the result was the same, with colors messed up and FFprobe saying the video is BT709. Also tried transcoding to DNxHR HQX profile (10 bits), same result.

  Any help would be greatly appreciated.

  Thanks in advance.

• The First Problem

  19 janvier 2011, par Multimedia Mike — HTML5

  A few years ago, The Linux Hater made the following poignant observation regarding Linux driver support :

  Drivers are only just the beginning... But for some reason y’all like to focus on the drivers. You know why lusers do that ? Because it just happens to be the problem that people notice first.

  And so it is with the HTML5 video codec debate, re-invigorated in the past week by Google’s announcement of dropping native H.264 support in their own HTML5 video tag implementation. As I read up on the fiery debate, I kept wondering why people are so obsessed with this issue. Then I remembered the Linux Hater’s post and realized that the video codec issue is simply the first problem that most people notice regarding HTML5 video.

  I appreciate that the video codec debate has prompted Niedermayer to post on his blog once more. Otherwise, I’m just munching popcorn on the sidelines, amused and mildly relieved that the various factions are vociferously attacking each other rather than that little project I help with at work.

  Getting back to the "first problem" aspect— there’s so much emphasis on the video codec ; I wonder why no one ever, ever mentions word one about an audio codec. AAC is typically the codec that pairs with H.264 in the MPEG stack. Dark Shikari once mentioned that "AAC’s licensing terms are exponentially more onerous than H.264′s. If Google didn’t want to use H.264, they would sure as hell not want to use AAC." Most people are probably using "H.264" to refer to the entire MPEG/H.264/AAC stack, even if they probably don’t understand what all of those pieces mean.

  Anyway, The Linux Hater’s driver piece continues :

  Once y’all have drivers, the fight will move to the next layer up. And like I said, it’s a lot harder at that layer.

  A few months ago, when I wanted to post the WebM output of my new VP8 encoder and thought it would be a nice touch to deliver it via a video tag, I ignored the video codec problem (just encoded a VP8/WebM file) only to immediately discover a problem at a different layer— specifically, embedding a file using a video tag triggers a full file download when the page is loaded, which is unacceptable from end user and web hosting perspectives. This is a known issue but doesn’t get as much attention, I guess because there are bigger problems to solve first (c.f. video codec issue).

  For other issues, check out the YouTube blog’s HTML5 post or Hulu’s post that also commented on HTML5. Issues such as video streaming flexibility, content protection, fullscreen video, webcam/microphone input, and numerous others are rarely mentioned in the debates. Only "video codec" is of paramount importance.

  But I’m lending too much weight to the cacophony of a largely uninformed internet debate. Realistically, I know there are many talented engineers down in the trenches working to solve at least some of these problems. To tie this in with the Linux driver example, I’m consistently stunned these days regarding how simple it is to get Linux working on a new computer— most commodity consumer hardware really does just work right out of the box. Maybe one day, we’ll wake up and find that HTML5 video has advanced to the point that it solves all of the relevant problems to make it the simple and obvious choice for delivering web video in nearly all situations.

  It won’t be this year.