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• Anomalie #2899 (Nouveau) : erreur 404 renvoie sur la page accueil sur certaines configurations d’a...

  9 novembre 2012, par erational -

  voir le thread du forum http://forum.spip.net/fr_236908.html#forum246586 sur certains configuration apache, le htaccess de base avec 404 activé ne fonctionne pas bien. au lieu de tomber sur l’erreur personnalisée 404, on tombe sur la page d’accueil. le patch proposé serait de revenir à (...)

• Anomalie #2787 : La compression HTML mange les retour ligne dans les formulaires

  8 août 2012, par nicolas -

  Dans plugins-dist/forum/formulaires/forum.html, je place #ENVtexte avant la ligne 24 J’obtiens ceci : un exemple de commentaire un autre encore un Mes retours chariot sont perdus d’une ligne à l’autre… J’ai envie de dire WTF !

• avcodec/vp3 : Make parsing Theora Huffman tables more spec-compliant

  20 octobre 2020, par Andreas Rheinhardt

  avcodec/vp3 : Make parsing Theora Huffman tables more spec-compliant
  Theora allows to use custom Huffman tables which are coded in the
  
  bitstream as a tree : Whether the next node is a leaf or not is coded
  
  in a bit ; each node itself contains a five bit token. Each tree can
  
  contain at most 32 leafs ; typically they contain exactly 32 with the 32
  
  symbols forming a permutation of 0..31. Yet the standard does not impose
  
  either of these requirements. It explicitly allows less than 32 leafs
  
  and multiple codes with the same token.
  But our decoder used an algorithm that required the codes->token mapping
  
  to be injective and that also presumed that there be at least two leafs :
  
  Instead of using an array for codes, tokens and code lengths, the
  
  decoder only had arrays for codes and code lengths. The code and length
  
  for a given token were stored in entry[token]. As no symbols table was
  
  used when initializing the VLC, the default one applied and therefore
  
  the entry[token] got the symbol token (if the length of said entry is >0).
  
  Yet if multiple codes had the same token, the codes and lengths from the
  
  later token would overwrite the earlier codes and lengths.
  Furthermore, less than 32 leafs could also lead to problems : Namely if
  
  this was not the first time Huffman tables have been parsed in which
  
  case the array is not zeroed initially so that old entries could make
  
  the new table invalid.
  libtheora seems to always use 32 leafs and no duplicate tokens ; I am not
  
  aware of any existing valid files that do not.
  This is fixed by using a codes, symbols and lengths array when
  
  initializing the VLC. In order to reduce the amount of stuff kept in the
  
  context only the symbols and lengths (which both fit into an uint8_t)
  
  are kept in the context ; the codes are derived from the lengths
  
  immediately before creating the tables.
  There is now only one thing left which is not spec-compliant : Trees with
  
  only one node (which has length zero) are not supported by
  
  ff_init_vlc_sparse() yet.
  Reviewed-by : Peter Ross <pross@xvid.org>
  
  Signed-off-by : Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
  

  • [DH] libavcodec/vp3.c