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Le profil des utilisateurs
12 avril 2011, parChaque utilisateur dispose d’une page de profil lui permettant de modifier ses informations personnelle. Dans le menu de haut de page par défaut, un élément de menu est automatiquement créé à l’initialisation de MediaSPIP, visible uniquement si le visiteur est identifié sur le site.
L’utilisateur a accès à la modification de profil depuis sa page auteur, un lien dans la navigation "Modifier votre profil" est (...) -
Configurer la prise en compte des langues
15 novembre 2010, parAccéder à la configuration et ajouter des langues prises en compte
Afin de configurer la prise en compte de nouvelles langues, il est nécessaire de se rendre dans la partie "Administrer" du site.
De là, dans le menu de navigation, vous pouvez accéder à une partie "Gestion des langues" permettant d’activer la prise en compte de nouvelles langues.
Chaque nouvelle langue ajoutée reste désactivable tant qu’aucun objet n’est créé dans cette langue. Dans ce cas, elle devient grisée dans la configuration et (...) -
XMP PHP
13 mai 2011, parDixit Wikipedia, XMP signifie :
Extensible Metadata Platform ou XMP est un format de métadonnées basé sur XML utilisé dans les applications PDF, de photographie et de graphisme. Il a été lancé par Adobe Systems en avril 2001 en étant intégré à la version 5.0 d’Adobe Acrobat.
Étant basé sur XML, il gère un ensemble de tags dynamiques pour l’utilisation dans le cadre du Web sémantique.
XMP permet d’enregistrer sous forme d’un document XML des informations relatives à un fichier : titre, auteur, historique (...)
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Extract Video Frames In Python
22 avril 2017, par TheNoneI want to extract video frames and save them as image.
import os, sys
from PIL import Image
a, b, c = os.popen3("ffmpeg -i test.avi")
out = c.read()
dp = out.index("Duration: ")
duration = out[dp+10:dp+out[dp:].index(",")]
hh, mm, ss = map(float, duration.split(":"))
total = (hh*60 + mm)*60 + ss
for i in xrange(9):
t = (i + 1) * total / 10
os.system("ffmpeg -i test.avi -ss %0.3fs frame%i.png" % (t, i))But I have this error :
FFmpeg version CVS, Copyright (c) 2000-2004 Fabrice Bellard
Mac OSX universal build for ffmpegX
configuration: --enable-memalign-hack --enable-mp3lame --enable-gpl --disable-vhook --disable-ffplay --disable-ffserver --enable-a52 --enable-xvid --enable-faac --enable-faad --enable-amr_nb --enable-amr_wb --enable-pthreads --enable-x264
libavutil version: 49.0.0
libavcodec version: 51.9.0
libavformat version: 50.4.0
built on Apr 15 2006 04:58:19, gcc: 4.0.1 (Apple Computer, Inc. build 5250)
Input #0, avi, from 'test.avi':
Duration: 00:00:30.5, start: 0.000000, bitrate: 465 kb/s
Stream #0.0, 25.00 fps(r): Video: mpeg4, yuv420p, 640x480
Stream #0.1: Audio: mp3, 32000 Hz, mono, 32 kb/s
Unable for find a suitable output format for 'frame0.png'Edit : ffmpeg -formats
FFmpeg version CVS, Copyright (c) 2000-2004 Fabrice Bellard
Mac OSX universal build for ffmpegX
configuration: --enable-memalign-hack --enable-mp3lame --enable-gpl --disable-vhook --disable-ffplay --disable-ffserver --enable-a52 --enable-xvid --enable-faac --enable-faad --enable-amr_nb --enable-amr_wb --enable-pthreads --enable-x264
libavutil version: 49.0.0
libavcodec version: 51.9.0
libavformat version: 50.4.0
built on Apr 15 2006 04:58:19, gcc: 4.0.1 (Apple Computer, Inc. build 5250)
File formats:
E 3g2 3gp2 format
E 3gp 3gp format
D 4xm 4X Technologies format
D RoQ Id RoQ format
D aac ADTS AAC
DE ac3 raw ac3
E adts ADTS AAC
DE aiff Audio IFF
DE alaw pcm A law format
DE amr 3gpp amr file format
DE asf asf format
E asf_stream asf format
DE au SUN AU Format
DE avi avi format
D avs avs format
E crc crc testing format
D daud D-Cinema audio format
D dts raw dts
DE dv DV video format
E dvd MPEG2 PS format (DVD VOB)
D ea Electronic Arts Multimedia Format
DE ffm ffm format
D film_cpk Sega FILM/CPK format
D flic FLI/FLC/FLX animation format
DE flv flv format
E framecrc framecrc testing format
DE gif GIF Animation
DE h261 raw h261
DE h263 raw h263
DE h264 raw H264 video format
D idcin Id CIN format
DE image image sequence
DE image2 image2 sequence
DE image2pipe piped image2 sequence
DE imagepipe piped image sequence
D ingenient Ingenient MJPEG
D ipmovie Interplay MVE format
DE m4v raw MPEG4 video format
D matroska Matroska file format
DE mjpeg MJPEG video
D mm American Laser Games MM format
DE mmf mmf format
E mov mov format
D mov,mp4,m4a,3gp,3g2,mj2 QuickTime/MPEG4/Motion JPEG 2000 format
E mp2 MPEG audio layer 2
DE mp3 MPEG audio layer 3
E mp4 mp4 format
DE mpeg MPEG1 System format
E mpeg1video MPEG video
E mpeg2video MPEG2 video
DE mpegts MPEG2 transport stream format
D mpegvideo MPEG video
E mpjpeg Mime multipart JPEG format
DE mulaw pcm mu law format
D nsv NullSoft Video format
E null null video format
DE nut nut format
D nuv NuppelVideo format
D ogg Ogg
E psp psp mp4 format
D psxstr Sony Playstation STR format
DE rawvideo raw video format
D redir Redirector format
DE rm rm format
E rtp RTP output format
D rtsp RTSP input format
DE s16be pcm signed 16 bit big endian format
DE s16le pcm signed 16 bit little endian format
DE s8 pcm signed 8 bit format
D sdp SDP
D shn raw shorten
D smk Smacker Video
D sol Sierra SOL Format
E svcd MPEG2 PS format (VOB)
DE swf Flash format
D tta true-audio
DE u16be pcm unsigned 16 bit big endian format
DE u16le pcm unsigned 16 bit little endian format
DE u8 pcm unsigned 8 bit format
E vcd MPEG1 System format (VCD)
D vmd Sierra VMD format
E vob MPEG2 PS format (VOB)
DE voc Creative Voice File format
DE wav wav format
D wc3movie Wing Commander III movie format
D wsaud Westwood Studios audio format
D wsvqa Westwood Studios VQA format
DE yuv4mpegpipe YUV4MPEG pipe format
Image formats (filename extensions, if any, follow):
DE gif gif
Codecs:
D V 4xm
D V D 8bps
DEA aac
D V D aasc
DEA ac3
DEA adpcm_4xm
DEA adpcm_adx
DEA adpcm_ct
DEA adpcm_ea
DEA adpcm_ima_dk3
DEA adpcm_ima_dk4
DEA adpcm_ima_qt
DEA adpcm_ima_smjpeg
DEA adpcm_ima_wav
DEA adpcm_ima_ws
DEA adpcm_ms
DEA adpcm_sbpro_2
DEA adpcm_sbpro_3
DEA adpcm_sbpro_4
DEA adpcm_swf
DEA adpcm_xa
DEA adpcm_yamaha
D A alac
DEA amr_nb
DEA amr_wb
DEV D asv1
DEV D asv2
D V D avs
D V bmp
D V D camstudio
D V D camtasia
D V D cinepak
D V D cljr
D A cook
D V D cyuv
DES dvbsub
DES dvdsub
DEV D dvvideo
DEV D ffv1
DEVSD ffvhuff
D A flac
D V D flic
DEVSD flv
D V D fraps
DEA g726
DEV D h261
DEVSDT h263
D VSD h263i
EV h263p
DEV DT h264
DEVSD huffyuv
D V D idcinvideo
D V D indeo2
D V indeo3
D A interplay_dpcm
D V D interplayvideo
EV jpegls
D V kmvc
EV ljpeg
D V D loco
D A mace3
D A mace6
D V D mdec
DEV D mjpeg
D V D mjpegb
D V D mmvideo
DEA mp2
DEA mp3
D A mp3adu
D A mp3on4
DEVSDT mpeg1video
DEVSDT mpeg2video
DEVSDT mpeg4
D A mpeg4aac
D VSDT mpegvideo
DEVSD msmpeg4
DEVSD msmpeg4v1
DEVSD msmpeg4v2
D V D msrle
D V D msvideo1
D V D mszh
D V D nuv
DEV pam
DEV pbm
DEA pcm_alaw
DEA pcm_mulaw
DEA pcm_s16be
DEA pcm_s16le
DEA pcm_s24be
DEA pcm_s24daud
DEA pcm_s24le
DEA pcm_s32be
DEA pcm_s32le
DEA pcm_s8
DEA pcm_u16be
DEA pcm_u16le
DEA pcm_u24be
DEA pcm_u24le
DEA pcm_u32be
DEA pcm_u32le
DEA pcm_u8
DEV pgm
DEV pgmyuv
DEV png
DEV ppm
D A qdm2
D V D qdraw
D V D qpeg
D V D qtrle
DEV rawvideo
D A real_144
D A real_288
D A roq_dpcm
D V D roqvideo
D V D rpza
DEV D rv10
DEV D rv20
D A shorten
D A smackaud
D V smackvid
D V D smc
DEV snow
D A sol_dpcm
DEA sonic
EA sonicls
D V D sp5x
DEV D svq1
D VSD svq3
D V theora
D V D truemotion1
D V D truemotion2
D A truespeech
D A tta
D V D ultimotion
D V vc9
D V D vcr1
D A vmdaudio
D V D vmdvideo
D A vorbis
D V vp3
D V D vqavideo
D A wmav1
D A wmav2
DEVSD wmv1
DEVSD wmv2
D V D wnv1
D A ws_snd1
D A xan_dpcm
D V D xan_wc3
D V D xl
EV xvid
DEV D zlib
D V zmbv
Supported file protocols:
file: pipe: udp: rtp: tcp: http:
Frame size, frame rate abbreviations:
ntsc pal qntsc qpal sntsc spal film ntsc-film sqcif qcif cif 4cif
Motion estimation methods:
zero(fastest) full(slowest) log phods epzs(default) x1 hex umh iter
Note, the names of encoders and decoders dont always match, so there are
several cases where the above table shows encoder only or decoder only entries
even though both encoding and decoding are supported for example, the h263
decoder corresponds to the h263 and h263p encoders, for file formats its even
worseWhat is wrong in my code ? Thanks in advance
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Révision 19605 : Ne pas appeler count() a l’init des iterateurs car cela provoque une double requ...
19 juin 2012, par cedric -la fonction count() de l’iterateur declenchera le calcul si elle est appelee A priori ne casse rien car ->total n’est jamais lu en direct, ce qui est a proscrire dorenavant
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More Weird VP8 Encodings
10 décembre 2010, par Multimedia Mike — VP8When I announced that I had transitioned my VP8 encoder’s status from "toy" to "working", Jim L. lamented the loss of humorous posts about oddly encoded images output from my encoder. Not so ! There are still plenty of features that I have yet to implement, each of which carries the possibility of bizarre images.
For example, I dusted off my work-in-progress intra 4x4 encoding, fixed a few of the more obvious bugs, and told the encoder to encode the first block in 4x4 mode and the rest in the usual, working, debugged 16x16 mode. The results of the first pass surprised me :
The reason this surprised me was that I intuitively expected one of 2 outcomes :
- Perfect image right away since everything is correct (very unlikely but not outside the realm of possibility)
- Total garbage with, at most, the first macroblock looking somewhat legible ; this would be due to having some of the first macroblock correct but completely desynchronizing the bitstream for the purpose of decoding the rest of the coefficients.
I absolutely did not expect the first macroblock to look messed up but for the rest of the picture to look fine. For fun, I reversed the logic and encoded the first block as 16x16 and the rest with the experimental 4x4 mode :
If you examine carefully, you will see that the color planes are correct (though faint). There just isn’t much going on in the luma plane. This made sense when I noticed the encoder was encoding a blank (undefined, actually) set of luma coefficients for 4x4 mode macroblocks due to a bug. This helps to rationalize the first image as well— the first macroblock was encoding nonsense for the first macroblock which messed up the macroblocks which immediately surrounded it. Eventually, macroblock decoding got back on track when the prediction modes weren’t relying on the errantly decoded macroblocks.
After I fixed that bug, I let the 4x4 mode rip through the whole image. That’s when I got what I am terming the "dark and gritty reboot of Big Buck Bunny" :
Fortunately, this also turned out to be traceable to a pretty obvious code bug.
One day, this VP8 encoder might do the right thing while implementing all of the algorithm’s features. In the meantime, it’s at least entertaining to watch it make mistakes.
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