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Rennes Emotion Map 2010-11
19 octobre 2011, par
Mis à jour : Juillet 2013
Langue : français
Type : Texte
Autres articles (70)
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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.
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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 (...)
Sur d’autres sites (7322)
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Video streaming- control frame rate x264
3 mars 2017, par H.AI’m new to video coding, I found this https://github.com/RafaelPalomar/H264LiveStreamer application code very useful to my project. I want to live stream a webcam over RTP . However, I’m having problem selecting the Frame Per Seconds (FPS). below is the function that controls the encoding param.
void x264Encoder::initilize()
{
x264_param_default_preset(&parameters, "veryfast", "zerolatency");
parameters.i_log_level = X264_LOG_DEBUG;
parameters.i_threads = 1;
parameters.i_width = 640;
parameters.i_height = 480;
parameters.i_fps_num = 25;
parameters.i_fps_den = 1;
parameters.i_keyint_max = 25;
parameters.b_intra_refresh = 1;
parameters.rc.i_rc_method = X264_RC_CRF;
parameters.rc.i_vbv_buffer_size = 1000000;
parameters.rc.i_vbv_max_bitrate = 90000;
parameters.rc.f_rf_constant = 25;
parameters.rc.f_rf_constant_max = 35;
parameters.i_sps_id = 7;
// the following two value you should keep 1
parameters.b_repeat_headers = 1; // to get header before every I-Frame
parameters.b_annexb = 1; // put start code in front of nal. we will remove start code later
x264_param_apply_profile(&parameters, "baseline");
encoder = x264_encoder_open(&parameters);
x264_picture_alloc(&picture_in, X264_CSP_I420, parameters.i_width, parameters.i_height);
picture_in.i_type = X264_TYPE_AUTO;
picture_in.img.i_csp = X264_CSP_I420;
// i have initilized my color space converter for BGR24 to YUV420 because my opencv video capture gives BGR24 image. You can initilize according to your input pixelFormat
convertContext = sws_getContext(parameters.i_width,parameters.i_height, PIX_FMT_BGR24, parameters.i_width,parameters.i_height,PIX_FMT_YUV420P, SWS_FAST_BILINEAR, NULL, NULL, NULL);
}I’m using VLC as client whatever number i set i_fps_num to, I always get 12-14 FPS. fore example, in VLC Codec tab shows 25 FPS but in Stream statistics tab it shows it only display 13 FPS on average. here is the X264 encoder output
x264 [debug]: frame= 72 QP=22.24 NAL=2 Slice:P Poc:144 I:97 P:116 SKIP:987 size=1464 bytes
x264 [info]: frame I:1 Avg QP:20.06 size: 17848
x264 [info]: frame P:72 Avg QP:22.12 size: 1337
x264 [info]: mb I I16..4: 40.2% 0.0% 59.8%
x264 [info]: mb P I16..4: 3.1% 0.0% 2.3% P16..4: 8.3% 2.0% 0.6% 0.0% 0.0% skip:83.7%
x264 [info]: coded y,uvDC,uvAC intra: 53.6% 46.4% 7.4% inter: 3.0% 1.6% 0.0%
x264 [info]: i16 v,h,dc,p: 11% 65% 12% 12%
x264 [info]: i4 v,h,dc,ddl,ddr,vr,hd,vl,hu: 15% 46% 16% 3% 4% 3% 5% 3% 6%
x264 [info]: i8c dc,h,v,p: 46% 42% 10% 2%
x264 [info]: kb/s:312.60the last frame number that was encoded is 72 while in VLC stream statistics it shows that 133 frames are Displayed and 66 blocks are decoded for 10 seconds streaming in addition the video playback is bursty.
my question is how to change the x264 parameters to get 25 FPS ?
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Pims.open Throws "UnkownFormat Error" with "Invalid Argument" On One Machine But Not on Another
12 août 2021, par KaceBellamyI'm trying to do some video processing for a physics experiment, and I want to do it on my much more powerful Windows desktop computer as opposed to my Mac laptop.


The following code works like a dream when run as a Jupyter notebook on my Mac :


import matplotlib as mpl
from mpl_toolkits import mplot3d
import pims
import trackpy as tp 

@pims.pipeline
def gray(image):
 return image[:, :, 1] # Take just the green channel

frames = gray(pims.open('output.mp4'))



but on my Windows machine I get this error :


---------------------------------------------------------------------------
UnknownFormatError Traceback (most recent call last)
~\AppData\Local\Temp/ipykernel_12152/704954007.py in <module>
 1 #Actually converts the video. Might be VERY processor intensive... or not?
----> 2 frames = gray(pims.open('output.mp4')) #Make the File Name whatever file you like!

~\miniconda3\lib\site-packages\pims\api.py in open(sequence, **kwargs)
 207 warn(message)
 208 exceptions += message + '\n'
--> 209 raise UnknownFormatError("All handlers returned exceptions:\n" + exceptions)
 210 
 211 

UnknownFormatError: All handlers returned exceptions:
<class> errored: [Errno 22] Invalid argument: 'output.mp4'
<class> errored: [Errno 22] Invalid argument: 'output.mp4'
<class> errored: Could not load meta information
=== stderr ===

ffmpeg version 4.2.2 Copyright (c) 2000-2019 the FFmpeg developers
 built with gcc 9.2.1 (GCC) 20200122
 configuration: --enable-gpl --enable-version3 --enable-sdl2 --enable-fontconfig --enable-gnutls --enable-iconv --enable-libass --enable-libdav1d --enable-libbluray --enable-libfreetype --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-libopus --enable-libshine --enable-libsnappy --enable-libsoxr --enable-libtheora --enable-libtwolame --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxml2 --enable-libzimg --enable-lzma --enable-zlib --enable-gmp --enable-libvidstab --enable-libvorbis --enable-libvo-amrwbenc --enable-libmysofa --enable-libspeex --enable-libxvid --enable-libaom --enable-libmfx --enable-amf --enable-ffnvcodec --enable-cuvid --enable-d3d11va --enable-nvenc --enable-nvdec --enable-dxva2 --enable-avisynth --enable-libopenmpt
 libavutil 56. 31.100 / 56. 31.100
 libavcodec 58. 54.100 / 58. 54.100
 libavformat 58. 29.100 / 58. 29.100
 libavdevice 58. 8.100 / 58. 8.100
 libavfilter 7. 57.100 / 7. 57.100
 libswscale 5. 5.100 / 5. 5.100
 libswresample 3. 5.100 / 3. 5.100
 libpostproc 55. 5.100 / 55. 5.100
C:\Users\Callum\OneDrive - The University of Chicago\output.mp4: Invalid argument
<class> errored: MoviePy error: failed to read the duration of file output.mp4.
Here are the file infos returned by ffmpeg:

ffmpeg version 4.2.2 Copyright (c) 2000-2019 the FFmpeg developers
 built with gcc 9.2.1 (GCC) 20200122
 configuration: --enable-gpl --enable-version3 --enable-sdl2 --enable-fontconfig --enable-gnutls --enable-iconv --enable-libass --enable-libdav1d --enable-libbluray --enable-libfreetype --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-libopus --enable-libshine --enable-libsnappy --enable-libsoxr --enable-libtheora --enable-libtwolame --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxml2 --enable-libzimg --enable-lzma --enable-zlib --enable-gmp --enable-libvidstab --enable-libvorbis --enable-libvo-amrwbenc --enable-libmysofa --enable-libspeex --enable-libxvid --enable-libaom --enable-libmfx --enable-amf --enable-ffnvcodec --enable-cuvid --enable-d3d11va --enable-nvenc --enable-nvdec --enable-dxva2 --enable-avisynth --enable-libopenmpt
 libavutil 56. 31.100 / 56. 31.100
 libavcodec 58. 54.100 / 58. 54.100
 libavformat 58. 29.100 / 58. 29.100
 libavdevice 58. 8.100 / 58. 8.100
 libavfilter 7. 57.100 / 7. 57.100
 libswscale 5. 5.100 / 5. 5.100
 libswresample 3. 5.100 / 3. 5.100
 libpostproc 55. 5.100 / 55. 5.100
output.mp4: Invalid argument
</class></class></class></class></module>


output.mp4 is just a run of the mill video file taken on a CCD camera ; I've tried converting it to a .MOV, I've tried other video files taken on different cameras, and I've tried running the file through FFmpeg to impose a 30 fps framerate ; everything I've tried works fine on my Mac and throws the above error on my Windows machine.


For reference, I installed necessary packages for this code on both machines this morning, so it should all be up to date and the same on both.


Any ideas as to what's up ? Thanks !


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