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MediaSPIP Simple : futur thème graphique par défaut ?
26 septembre 2013, par
Mis à jour : Octobre 2013
Langue : français
Type : Video
Autres articles (71)
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Installation en mode ferme
4 février 2011, parLe mode ferme permet d’héberger plusieurs sites de type MediaSPIP en n’installant qu’une seule fois son noyau fonctionnel.
C’est la méthode que nous utilisons sur cette même plateforme.
L’utilisation en mode ferme nécessite de connaïtre un peu le mécanisme de SPIP contrairement à la version standalone qui ne nécessite pas réellement de connaissances spécifique puisque l’espace privé habituel de SPIP n’est plus utilisé.
Dans un premier temps, vous devez avoir installé les mêmes fichiers que l’installation (...) -
Récupération d’informations sur le site maître à l’installation d’une instance
26 novembre 2010, parUtilité
Sur le site principal, une instance de mutualisation est définie par plusieurs choses : Les données dans la table spip_mutus ; Son logo ; Son auteur principal (id_admin dans la table spip_mutus correspondant à un id_auteur de la table spip_auteurs)qui sera le seul à pouvoir créer définitivement l’instance de mutualisation ;
Il peut donc être tout à fait judicieux de vouloir récupérer certaines de ces informations afin de compléter l’installation d’une instance pour, par exemple : récupérer le (...) -
MediaSPIP v0.2
21 juin 2013, parMediaSPIP 0.2 is the first MediaSPIP stable release.
Its official release date is June 21, 2013 and is announced here.
The zip file provided here only contains the sources of MediaSPIP in its standalone version.
To get a working installation, you must manually install all-software dependencies on the server.
If you want to use this archive for an installation in "farm mode", you will also need to proceed to other manual (...)
Sur d’autres sites (4366)
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ffmpeg - excerpt from a large video file, preserving its additional streams
29 mars 2024, par BabaGI have a video file that has a stereo audio track and two additional stereo streams of audio. I'll include the mediainfo details at the end. The closest I've come to being able to excerpt a portion of this large file, while keeping all of the streams, is this :


ffmpeg -i output.mov -ss 1200 -map 0 -c copy -to 00:21:00 -map 0:1 -c:a copy -map 0:2 -c:a copy output_excerpt.mov

This seems to give me a bunch of extra streams, though. What's a correct command to do this ?


I was expecting four streams, one video, a second for the video's main audio, then two additional strems of 2channels each. This is what my command shows in mediainfo :


Complete name : output_excerpt.mov
Format : MPEG-4
Format profile : QuickTime
Codec ID : qt 0000.02 (qt )
File size : 492 MiB
Duration : 1 min 0 s
Overall bit rate mode : Variable
Overall bit rate : 68.8 Mb/s
Frame rate : 29.970 FPS
Writing application : Lavf58.76.100

Video
ID : 1
Format : ProRes
Format version : Version 0
Format profile : 422 HQ
Codec ID : apch
Duration : 1 min 0 s
Source duration : 59 s 993 ms
Bit rate mode : Variable
Bit rate : 58.8 Mb/s
Width : 720 pixels
Height : 540 pixels
Display aspect ratio : 4:3
Frame rate mode : Constant
Frame rate : 29.970 (30000/1001) FPS
Color space : YUV
Chroma subsampling : 4:2:2
Scan type : Progressive
Bits/(Pixel*Frame) : 5.043
Stream size : 421 MiB (85%)
Source stream size : 440 MiB (89%)
Writing library : Apple
Matrix coefficients : BT.470 System B/G
mdhd_Duration : 60025

Audio #1
ID : 2
Format : PCM
Format settings : Little / Signed
Codec ID : sowt
Duration : 1 min 0 s
Bit rate mode : Constant
Bit rate : 1 536 kb/s
Channel(s) : 2 channels
Channel layout : L R
Sampling rate : 48.0 kHz
Bit depth : 16 bits
Stream size : 11.0 MiB (2%)
Default : Yes
Alternate group : 1

Audio #2
ID : 3
Format : PCM
Format settings : Little / Signed
Codec ID : sowt
Duration : 1 min 0 s
Source duration : 1 min 0 s
Bit rate mode : Constant
Bit rate : 1 411.2 kb/s
Channel(s) : 2 channels
Channel layout : L R
Sampling rate : 44.1 kHz
Bit depth : 16 bits
Stream size : 10.1 MiB (2%)
Source stream size : 10.1 MiB (2%)
Default : No
Alternate group : 2
mdhd_Duration : 60008

Audio #3
ID : 4
Format : PCM
Format settings : Little / Signed
Codec ID : sowt
Duration : 1 min 0 s
Source duration : 1 min 0 s
Bit rate mode : Constant
Bit rate : 1 411.2 kb/s
Channel(s) : 2 channels
Channel layout : L R
Sampling rate : 44.1 kHz
Bit depth : 16 bits
Stream size : 10.1 MiB (2%)
Source stream size : 10.1 MiB (2%)
Default : No
Alternate group : 3
mdhd_Duration : 60008

Audio #4
ID : 5
Format : PCM
Format settings : Little / Signed
Codec ID : sowt
Duration : 1 min 0 s
Bit rate mode : Constant
Bit rate : 1 536 kb/s
Channel(s) : 2 channels
Channel layout : L R
Sampling rate : 48.0 kHz
Bit depth : 16 bits
Stream size : 11.0 MiB (2%)
Default : Yes
Alternate group : 4

Audio #5
ID : 6
Format : PCM
Format settings : Little / Signed
Codec ID : sowt
Duration : 1 min 0 s
Source duration : 1 min 0 s
Bit rate mode : Constant
Bit rate : 1 411.2 kb/s
Channel(s) : 2 channels
Channel layout : L R
Sampling rate : 44.1 kHz
Bit depth : 16 bits
Stream size : 10.1 MiB (2%)
Source stream size : 10.1 MiB (2%)
Default : No
Alternate group : 5
mdhd_Duration : 60008


thanks for any guidance on this.


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Is there a way to find out whether ffmpeg is performing optimally in my system using a ffmpeg command of sorts ?
17 octobre 2020, par Aspiring DevI'm encoding a file (mediainfo below) using the following command :


ffmpeg -i AHomeMovie.mkv -map 0 -c copy -c:v libx264 -preset veryslow -crf 17 -c:a aac -b:a 256k -threads 8 resultdir/AHomeMovie.mkv


And getting more or less the following performance after a couple of minutes :


frame= 2036 fps=2.5 q=22.0 size= 87535kB time=00:01:25.25 bitrate=8411.2kbits/s speed=0.104x 


Is this normal performance for a laptop with a i7-8550U, 16gb of RAM, UHD graphics 620 running Linux ? Is there a way to find out whether ffmpeg is performing optimally using a ffmpeg command of sorts ? I know it's commodity hardware by now but I just want to get some perspective on how the system is performing. I'm aware that I can use a different -preset speed btw.


Mediainfo :


General
Unique ID : 25145236523685421256398752247554522365 (0x14258745965823652446224452555874)
Complete name : AHomeMovie.mkv
Format : Matroska
Format version : Version 4
File size : 6.35 GiB
Duration : 22 min 47 s
Overall bit rate mode : Variable
Overall bit rate : 39.9 Mb/s
Movie name : A Home Movie
Encoded date : UTC 2020-09-10 22:10:12
Writing application : mkvmerge v42.0.0 ('Overtime') 64-bit
Writing library : libebml v1.3.10 + libmatroska v1.5.2

Video
ID : 1
Format : AVC
Format/Info : Advanced Video Codec
Format profile : High@L4.1
Format settings : CABAC / 4 Ref Frames
Format settings, CABAC : Yes
Format settings, Reference frames : 4 frames
Codec ID : V_MPEG4/ISO/AVC
Duration : 22 min 45 s
Bit rate mode : Variable
Bit rate : 38.0 Mb/s
Maximum bit rate : 40.0 Mb/s
Width : 1 920 pixels
Height : 1 080 pixels
Display aspect ratio : 16:9
Frame rate mode : Constant
Frame rate : 23.976 (24000/1001) FPS
Color space : YUV
Chroma subsampling : 4:2:0
Bit depth : 8 bits
Scan type : Progressive
Bits/(Pixel*Frame) : 0.764
Stream size : 6.04 GiB (95%)
Default : Yes
Forced : No

Audio #1
ID : 2
Format : FLAC
Format/Info : Free Lossless Audio Codec
Codec ID : A_FLAC
Duration : 22 min 45 s
Bit rate mode : Variable
Bit rate : 614 kb/s
Channel(s) : 2 channels
Channel layout : L R
Sampling rate : 48.0 kHz
Frame rate : 11.719 FPS (4096 SPF)
Bit depth : 16 bits
Compression mode : Lossless
Stream size : 100 MiB (2%)
Writing library : libFLAC 1.2.1 (UTC 2007-09-17)
Language : Japanese
Default : Yes
Forced : No

Audio #2
ID : 3
Format : FLAC
Format/Info : Free Lossless Audio Codec
Codec ID : A_FLAC
Duration : 22 min 46 s
Bit rate mode : Variable
Bit rate : 1 317 kb/s
Channel(s) : 2 channels
Channel layout : L R
Sampling rate : 48.0 kHz
Frame rate : 11.719 FPS (4096 SPF)
Bit depth : 24 bits
Compression mode : Lossless
Delay relative to video : 24 ms
Stream size : 215 MiB (3%)
Writing library : libFLAC 1.2.1 (UTC 2007-09-17)
Language : English
Default : No
Forced : No


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How do I remux/transcode a progressive file in ffmpeg ?
3 décembre 2014, par Levi RobertsHere’s what I’m trying to do.
My primary objective is to remux or transcode a currently downloading media file for AppleTV and iOS compatible streaming.
I am doing this by looking at the media file and only transcoding when necessary, otherwise it will only alter the container the video/audio lives in. This will reduce overhead for files that are already compatible. The specific compatible output I am looking for is AppleTV3 and iOS.
I have a file that is progressive, meaning that it is downloading using another download manager or another app without the help of
nodejs. This file may or may not have themoovinformation available in the beginning of the file. It just so happens, that I believe my test file does.I have some code that is partially working and it would make sense to be able to get this code fully working. That said, I’m not dismissing alternative ways to do this.
My primary problem (I think) has to do with the
moovheader location or that it’s being set incorrectly. I’m hoping the fix is as simple as correcting my poorffmpegknowledge with command line parameters.I am piping the file to and from
ffmpegviaGrowingFileandfs.createWriteStreamrespectively.My code for doing so is :
var fs = require('fs');
var child = require('child_process');
var GrowingFile = require('growing-file');
var input_file = GrowingFile.open('./tmp/input.mp4');
var output_file = fs.createWriteStream('./tmp/output.m4v');
// I've tried various args and ffmpeg params here without success.
var args = ['-re', '-i', 'pipe:0', '-g', '52', '-ab', '64k', '-vcodec', 'libx264', '-vb', '448k', '-f', 'mp4', '-movflags', 'frag_keyframe+faststart', 'pipe:1'];
var trans_proc = child.spawn('ffmpeg', args, null);
input_file.pipe(trans_proc.stdin);
trans_proc.stdout.pipe(output_file);I am also temporarily trying to make these files work as intended via
ffmpegcommand line alone, without success. That command is :ffmpeg -i original.mp4 -vcodec copy -r 24 output.m4vSnippet of
original.mp4viamediainfo:General
Format : MPEG-4
Format profile : Base Media / Version 2
Codec ID : mp42
File size : 9.87 MiB
Duration : 43mn 14s
Overall bit rate mode : Variable
Overall bit rate : 31.9 Kbp
Video
Format : AVC
Format/Info : Advanced Video Codec
Format profile : High@L2.1
Codec ID : avc1
Duration : 43mn 14s
Width : 480 pixels
Height : 268 pixels
Color space : YUV
Scan type : Progressive
Stream size : 67.5 MiB
Audio
Format : AAC
Format/Info : Advanced Audio Codec
Format profile : LC
Codec ID : 40
Duration : 43mn 14s
Bit rate mode : Variable
Bit rate : 96.0 KbpsWhat’s happening is that
output.m4vhas an incorrect duration of only the part of the file that’s already downloaded. The video reaches the end or a refresh happens to make the duration longer. This process repeats until theoriginalfile is done downloading. What I want is to be able to emulate/clone the duration of the input file to the output file .
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