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  • Déploiements possibles

    31 janvier 2010, par

    Deux types de déploiements sont envisageable dépendant de deux aspects : La méthode d’installation envisagée (en standalone ou en ferme) ; Le nombre d’encodages journaliers et la fréquentation envisagés ;
    L’encodage de vidéos est un processus lourd consommant énormément de ressources système (CPU et RAM), il est nécessaire de prendre tout cela en considération. Ce système n’est donc possible que sur un ou plusieurs serveurs dédiés.
    Version mono serveur
    La version mono serveur consiste à n’utiliser qu’une (...)

  • Publier sur MédiaSpip

    13 juin 2013

    Puis-je poster des contenus à partir d’une tablette Ipad ?
    Oui, si votre Médiaspip installé est à la version 0.2 ou supérieure. Contacter au besoin l’administrateur de votre MédiaSpip pour le savoir

  • Use, discuss, criticize

    13 avril 2011, par

    Talk to people directly involved in MediaSPIP’s development, or to people around you who could use MediaSPIP to share, enhance or develop their creative projects.
    The bigger the community, the more MediaSPIP’s potential will be explored and the faster the software will evolve.
    A discussion list is available for all exchanges between users.

Sur d’autres sites (2801)

  • aaccoder : add a new perceptual noise substitution implementation

    2 juillet 2015, par Rostislav Pehlivanov
    aaccoder : add a new perceptual noise substitution implementation

    This commit finalizes the PNS implementation previously added to the encoder
    
by moving it to a seperate function search_for_pns() and thus making it
    
coder-generic. This new implementation makes use of the spread field of
    
the psy bands and the lambda quality feedback paremeter. The spread of the
    
spectrum in a band prevents PNS from being used excessively and thus preserve
    
more phase information in high frequencies.  The lambda parameter allows
    
the number of PNS-marked bands to vary based on the lambda parameter and the
    
amount of bits available, making better choices on which bands are to be marked
    
as noise. Comparisons with the previous PNS implementation can be found
    
here : https://trac.ffmpeg.org/attachment/wiki/Encode/AAC/
    

    This is V2 of the patch, the changes from the previous version being that this
    
version uses the new band->spread metric from aacpsy and normalizes the
    
energy using the group size. These changes were suggested by Claudio Freire
    
on the mailing list. Another change is the use of lambda to alter the
    
frequency threshold. This change makes the actual threshold frequencies
    
vary between +-2Khz of what’s specified, depending on frame encoding performance.
    

    Reviewed-by : Claudio Freire <klaussfreire@gmail.com>
    
Signed-off-by : Michael Niedermayer <michaelni@gmx.at>
    • [DH] libavcodec/aaccoder.c
    • [DH] libavcodec/aacenc.c
    • [DH] libavcodec/aacenc.h

  • aacenc : use the new function for setting special band scalefactor indices

    2 juillet 2015, par Rostislav Pehlivanov
    aacenc : use the new function for setting special band scalefactor indices

    This commit enables the function added with commit 7c10b87 and uses that
    
new function for setting any special scalefactor indices. This commit does
    
not change the behaviour of the encoder since no bands are being marked as
    
either NOISE_BT(due to the previous PNS implementation removed in the
    
previous commit) or INTENSITY_BT2/INTENSITY_BT.
    

    Reviewed-by : Claudio Freire <klaussfreire@gmail.com>
    
Signed-off-by : Michael Niedermayer <michaelni@gmx.at>
    • [DH] libavcodec/aaccoder.c
    • [DH] libavcodec/aacenc.c
    • [DH] libavcodec/aacenc.h

  • AAC Encoder : clipping avoidance

    21 juillet 2015, par Claudio Freire
    AAC Encoder : clipping avoidance

    Avoid clipping due to quantization noise to produce audible
    
artifacts, by detecting near-clipping signals and both attenuating
    
them a little and encoding escape-encoded bands (usually the
    
loudest) rounding towards zero instead of nearest, which tends to
    
decrease overall energy and thus clipping.
    

    Currently fate tests measure numerical error so this change makes
    
tests using asynth (which are near clipping) report higher error
    
not less, because of window attenuation. Yet, they sound better,
    
not worse (albeit subtle, other samples aren’t subtle at all).
    
Only measuring psychoacoustically weighted error would make for
    
a representative test, so that will be left for a future patch.
    

    Signed-off-by : Michael Niedermayer <michael@niedermayer.cc>
    • [DH] libavcodec/aac.h
    • [DH] libavcodec/aaccoder.c
    • [DH] libavcodec/aacenc.c
    • [DH] libavcodec/aacenc.h
    • [DH] libavcodec/aacpsy.c
    • [DH] libavcodec/psymodel.h
    • [DH] tests/fate/aac.mak

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