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  • Gestion des droits de création et d’édition des objets

    8 février 2011, par

    Par défaut, beaucoup de fonctionnalités sont limitées aux administrateurs mais restent configurables indépendamment pour modifier leur statut minimal d’utilisation notamment : la rédaction de contenus sur le site modifiables dans la gestion des templates de formulaires ; l’ajout de notes aux articles ; l’ajout de légendes et d’annotations sur les images ;

  • Supporting all media types

    13 avril 2011, par

    Unlike most software and media-sharing platforms, MediaSPIP aims to manage as many different media types as possible. The following are just a few examples from an ever-expanding list of supported formats : images : png, gif, jpg, bmp and more audio : MP3, Ogg, Wav and more video : AVI, MP4, OGV, mpg, mov, wmv and more text, code and other data : OpenOffice, Microsoft Office (Word, PowerPoint, Excel), web (html, CSS), LaTeX, Google Earth and (...)

  • Dépôt de média et thèmes par FTP

    31 mai 2013, par

    L’outil MédiaSPIP traite aussi les média transférés par la voie FTP. Si vous préférez déposer par cette voie, récupérez les identifiants d’accès vers votre site MédiaSPIP et utilisez votre client FTP favori.
    Vous trouverez dès le départ les dossiers suivants dans votre espace FTP : config/ : dossier de configuration du site IMG/ : dossier des média déjà traités et en ligne sur le site local/ : répertoire cache du site web themes/ : les thèmes ou les feuilles de style personnalisées tmp/ : dossier de travail (...)

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  • Tracking User Acquisition and Social Media Activity with Piwik

    25 avril 2017, par Florian Hieß — Community

    Being able to monitor user acquisition and social media activity is essential for determining whether the outcome of your campaigns is in line with the business objectives. Determining the source of each website visit that gets you closer to your business goals enables you to focus your efforts in the directions that are worth it. In this article you will learn why it is important to identify your traffic sources and how you can track user acquisition with Piwik Analytics.

    Why Is It Important to Identify Traffic Sources on Your Website ?

    Since brands nowadays use multiple channels for promotion and advertising, identifying the touch points and traffic sources of a lead or customer seems to become more and more difficult. And yet, this channel multiplication is what makes the source of a purchase more important. Once you identify the traffic origin and how each source is performing you are able to increase your efforts on the best performers, both in terms of human resources and monetary investments, to attract more leads or customers in these marketing channels.

    The default referrer types are defined by :

    • Search engine
    • Direct traffic
    • Websites and
    • Campaigns

    But consider that within the “Campaigns” type, each of the following referrers is a possible traffic source for your website and can be tracked with the Piwik URL builder :

    • Google AdWords
    • Display Ads, Banners
    • Links in Newsletters, Emailing
    • Affiliate links
    • Tweets
    • Facebook Ads

    Measure your performance and conversion

    With so many options, wouldn’t you like to know which one of them worked best ? To rate channels based on their performance, you first need to establish conversion goals and attribution.

    A conversion can be anything from sign-ups or downloads to leads, registered users and even paying customers. Define conversions based on what you want people to do once they’ve landed on your website.

    Piwik Conversion Goals

    You need to define each conversion type in the Piwik dashboard, so that the analytics platform knows what to track. As far as attribution goes, Piwik by default links the conversion and attributes to the last seen (non-direct) referrer. You are able to change that to the first referrer in the attribution line by following the instructions in this conversion attribution FAQ.

    Track Your User Acquisition Right with Piwik

    Using the Piwik URL Builder tool, you can tag each URL you promote in your campaigns using relevant keywords. Provided that your URLs are tagged, whenever someone clicks on them, the campaign will be listed as the referrer in the Piwik dashboard. Once you’ve generated trackable URLs, you can include them in your social media posts which could be planned and scheduled using a social media management tool such as Swat.io.

    Piwik Campaign URL Builder

    Campaign URLs work wonders for telling which campaign helped you reach your goals faster, more efficiently and so on but they do have a downside. They only work for URLs that you’ve shared. If someone decides to share a link of yours on social media they won’t be tagged beforehands. This is where the Referrers section of Piwik comes in handy, as it acts as a backup for tracking traffic sources. The overview tab features a graph that can help you identify when spikes occurred.

    Piwik Referrer Overview

    As well as a numerical representation of the main referrer categories for the selected time period.

    Piwik Referrer Overview

    Switching from Overview to Websites & Social, you can see a graphical representation of the social networks acting as referrers. The visualization can be changed to bar graphs or table, and can be easily exported in various formats for reports.

    Piwik Referrer Websites and Social

    The websites list features not only the social referrers, but all of the websites generating visits to your website. With Piwik you should not have issues with referrer spam, as the Piwik core team has tackled this problem early on, as detailed in how to stop referrer spam. Our analytics spam blacklist is a public project on GitHub.

    Piwik Referrer Websites

    Assuming that you’re relying only on Facebook and VK.com for your campaigns, as the above screenshot would suggest, you might want to give paid advertising a try on these two social networks. Paid ads can increase reach and engagement, can get more relevant visitors to your website and can have a snowball effect in a short period of time.

    What Social Networks Can Piwik Track ?

    Piwik’s built-in social network list is quite extensive, as it currently features 70 platforms. The entries range from popular social networks such as Facebook, Twitter and LinkedIn to more obscure ones such as Renren. However, this list is not available by default, and to see it or alter it, you would need a third-party plugin.

    How Does the Referrers Manager Plugin for Piwik Work ?

    The Referrers Manager plugin for Piwik provides access to the list of search engines and social networks that this analytics platform can handle by default. The simple plugin can come in handy when sorting out referrers. First of all, it displays a list of all search engines and social networks that Piwik can handle by default. Secondly, it enables users to disable/enable the platform’s default social network list. And using Referrers Manager, you can add custom engines or social networks to the referrers list in case they’re not already available.

    Piwik Referrer Manager Addon

    Conclusions

    Piwik is a very capable analytics platform as it is, but combined with third-party plugins such as Referrers Manager, it can provide even better insights on where your visitors are coming from. Remember to correlate the referrers with goals in order to determine which website or social network performs best in your context. And don’t forget to assign a monetary revenue value to each goal, in order to determine your social media ROI with greater accuracy.

  • Linux Media Player Survey Circa 2001

    2 septembre 2010, par Multimedia Mike — General

    Here’s a document I scavenged from my archives. It was dated September 1, 2001 and I now publish it 9 years later. It serves as sort of a time capsule for the state of media player programs at the time. Looking back on this list, I can’t understand why I couldn’t find MPlayer while I was conducting this survey, especially since MPlayer is the project I eventually started to work for a few months after writing this piece.

    For a little context, I had been studying multimedia concepts and tech for a year and was itching to get my hands dirty with practical multimedia coding. But I wanted to tackle what I perceived as unsolved problems– like playback of proprietary codecs. I didn’t want to have to build a new media playback framework just to start working on my problems. So I surveyed the players available to see which ones I could plug into and use as a testbed for implementing new decoders.

    Regarding Real Player, I wrote : “We’re trying to move away from the proprietary, closed-source “solutions”. Heh. Was I really an insufferable open source idealist back in the day ?

    Anyway, here’s the text with some Where are they now ? commentary [in brackets] :


    Towards an All-Inclusive Media Playing Solution for Linux

    I don’t feel that the media playing solutions for Linux set their sights high enough, even though they do tend to be quite ambitious.

    I want to create a media player for Linux that can open a file, figure out what type of file it is (AVI, MOV, etc.), determine the compression algorithms used to encode the audio and video chunks inside (MPEG, Cinepak, Sorenson, etc.) and replay the file using the best audio, video, and CPU facilities available on the computer.

    Video and audio playback is a solved problem on Linux ; I don’t wish to solve that problem again. The problem that isn’t solved is reliance on proprietary multimedia solutions through some kind of WINE-like layer in order to decode compressed multimedia files.

    Survey of Linux solutions for decoding proprietary multimedia
    updated 2001-09-01

    AVI Player for XMMS
    This is based on Avifile. All the same advantages and limitations apply.
    [Top Google hit is a Freshmeat page that doesn’t indicate activity since 2001-2002.]

    Avifile
    This player does a great job at taking apart AVI and ASF files and then feeding the compressed chunks of multimedia data through to the binary Win32 decoders.

    The program is written in C++ and I’m not very good at interpreting that kind of code. But I’m learning all over again. Examining the object hierarchy, it appears that the designers had the foresight to include native support for decoders that are compiled into the program from source code. However, closer examination reveals that there is support for ONE source decoder and that’s the “decoder” for uncompressed data. Still, I tried to manipulate this routine to accept and decode data from other codecs but no dice. It’s really confounding. The program always crashes when I feed non-uncompressed data through the source decoder.
    [Lives at http://avifile.sourceforge.net/ ; not updated since 2006.]

    Real Player
    There’s not much to do with this since it is closed source and proprietary. Even though there is a plugin architecture, that’s not satisfactory. We’re trying to move away from the proprietary, closed-source “solutions”.
    [Still kickin’ with version 11.]

    XAnim
    This is a well-established Unix media player. To his credit, the author does as well as he can with the resources he has. In other words, he supports the non-proprietary video codecs well, and even has support for some proprietary video codecs through binary-only decoders.

    The source code is extremely difficult to work with as the author chose to use the X coding format which I’ve never seen used anywhere else except for X header files. The infrastructure for extending the program and supporting other codecs and file formats is there, I suppose, but I would have to wrap my head around the coding style. Maybe I can learn to work past that. The other thing that bothers me about this program is the decoding approach : It seems that each video decoder includes routines to decompress the multimedia data into every conceivable RGB and YUV output format. This seems backwards to me ; it seems better to have one decoder function that decodes the data into its native format it was compressed from (e.g., YV12 for MPEG data) and then pass that data to another layer of the program that’s in charge of presenting the data and possibly converting it if necessary. This layer would encompass highly-optimized software conversion routines including special CPU-specific instructions (e.g., MMX and SSE) and eliminate the need to place those routines in lots of other routines. But I’m getting ahead of myself.
    [This one was pretty much dead before I made this survey, the most recent update being in 1999. Still, we owe it much respect as the granddaddy of Unix multimedia playback programs.]

    Xine
    This seems like a promising program. It was originally designed to play MPEGs from DVDs. It can also play MPEG files on a hard drive and utilizes the Xv extensions for hardware YUV playback. It’s also supposed to play AVI files using the same technique as Avifile but I have never, ever gotten it to work. If an AVI file has both video and sound, the binary video decoder can’t decode any frames. If the AVI file has video and no sound, the program gets confused and crashes, as far as I can tell.

    Still, it’s promising, and I’ve been trying to work around these crashes. It doesn’t yet have the type of modularization I’d like to see. Right now, it tailored to suit MPEG playback and AVI playback is an afterthought. Still, it appears to have a generalized interface for dropping in new file demultiplexers.

    I tried to extend the program for supporting source decoders by rewriting w32codec.c from scratch. I’m not having a smooth time of it so far. I’m able to perform some manipulations on the output window. However, I can’t get the program to deal with an RGB image format. It has trouble allocating an RGB surface with XvShmCreateImage(). This isn’t suprising, per my limited knowledge of X which is that Xv applies to YUV images, but it could also apply to RGB images as well. Anyway, the program should be able to fall back on regular RGB pixmaps if that Xv call fails.

    Right now, this program is looking the most promising. It will take some work to extend the underlying infrastructure, but it seems doable since I know C quite well and can understand the flow of this program, as opposed to Avifile and its C++. The C code also compiles about 10 times faster.
    [My home project for many years after a brief flirtation with MPlayer. It is still alive ; its latest release was just a month ago.]

    XMovie
    This library is a Quicktime movie player. I haven’t looked at it too extensively yet, but I do remember looking at it at one point and reading the documentation that said it doesn’t support key frames. Still, I should examine it again since they released a new version recently.
    [Heroine Virtual still puts out some software but XMovie has not been updated since 2005.]

    XMPS
    This program compiles for me, but doesn’t do much else. It can play an MP3 file. I have been able to get MPEG movies to play through it, but it refuses to show the full video frame, constricting it to a small window (obviously a bug).
    [This project is hosted on SourceForge and is listed with a registration date of 2003, well after this survey was made. So the project obviously lived elsewhere in 2001. Meanwhile, it doesn’t look like any files ever made it to SF for hosting.]

    XTheater
    I can’t even get this program to compile. It’s supposed to be an MPEG player based on SMPEG. As such, it probably doesn’t hold much promise for being easily extended into a general media player.
    [Last updated in 2002.]

    GMerlin
    I can’t get this to compile yet. I have a bug report in to the dev group.
    [Updated consistently in the last 9 years. Last update was in February of this year. I can’t find any record of my bug report, though.]

  • FFmpeg concat creating corrupted video part (Media Info provided)

    6 mai 2022, par krv

    I am using concat to join a list of video files with the following command

    


    ffmpeg -f concat -safe 0 -i filesList.txt -c copy output.mp4 


    


    The issue here is that there are a few files that were recorded in slow motion on my phone. The slow-motion files have the same frame rate as the other files.

    


    But when concatenated the part where the slow-motion files are concatenated appears to be frozen / glitch (it does not play a single frame).

    


    I am able to seek forward and backward the part that does not play. So the portion of the video that contained normal files plays and as soon as the slow-motion video comes, nothing plays, and when a normal file comes it starts playing again.

    


    I am attaching the media Info of both files

    


    Info of the slow motion file :

    


    General
Complete name :     I:\concate Test\VID20210727114100.mp4
Format :    MPEG-4
Format profile :    Base Media / Version 2
Codec ID :  mp42 (isom/mp42)
File size :     27.6 MiB
Duration :  1 min 0 s
Overall bit rate :  3 825 kb/s
Encoded date :  UTC 2021-07-27 06:11:08
Tagged date :   UTC 2021-07-27 06:11:08
xyz :   +21.6146+071.2342/
com.android.version :   11

Video
ID :    1
Format :    HEVC
Format/Info :   High Efficiency Video Coding
Format profile :    Main@L3.1@Main
Codec ID :  hvc1
Codec ID/Info :     High Efficiency Video Coding
Duration :  1 min 0 s
Source duration :   1 min 0 s
Bit rate :  3 771 kb/s
Width :     1 280 pixels
Height :    720 pixels
Display aspect ratio :  16:9
Frame rate mode :   Variable
Frame rate :    30.000 FPS
Minimum frame rate :    29.910 FPS
Maximum frame rate :    30.090 FPS
Real frame rate :   240.000 FPS
Color space :   YUV
Chroma subsampling :    4:2:0
Bit depth :     8 bits
Bits/(Pixel*Frame) :    0.136
Stream size :   27.2 MiB (99%)
Source stream size :    27.2 MiB (99%)
Title :     VideoHandle
Language :  English
Encoded date :  UTC 2021-07-27 06:11:08
Tagged date :   UTC 2021-07-27 06:11:08
Color range :   Limited
Color primaries :   BT.709
Transfer characteristics :  BT.709
Matrix coefficients :   BT.709
mdhd_Duration :     60524
Codec configuration box :   hvcC


    


    Info of the regular video file

    


    
General
Complete name :     I:\concate Test\VID20210727113901.mp4
Format :    MPEG-4
Format profile :    Base Media / Version 2
Codec ID :  mp42 (isom/mp42)
File size :     39.0 MiB
Duration :  37 s 930 ms
Overall bit rate :  8 615 kb/s
Encoded date :  UTC 2021-07-27 06:09:40
Tagged date :   UTC 2021-07-27 06:09:40
xyz :   +21.6146+071.2342/
com.android.version :   11

Video
ID :    1
Format :    HEVC
Format/Info :   High Efficiency Video Coding
Format profile :    Main@L4@Main
Codec ID :  hvc1
Codec ID/Info :     High Efficiency Video Coding
Duration :  37 s 930 ms
Source duration :   37 s 900 ms
Bit rate :  8 408 kb/s
Width :     1 920 pixels
Height :    1 080 pixels
Display aspect ratio :  16:9
Frame rate mode :   Variable
Frame rate :    29.604 FPS
Minimum frame rate :    29.508 FPS
Maximum frame rate :    29.605 FPS
Real frame rate :   30.000 FPS
Color space :   YUV
Chroma subsampling :    4:2:0
Bit depth :     8 bits
Bits/(Pixel*Frame) :    0.137
Stream size :   38.0 MiB (98%)
Source stream size :    38.0 MiB (98%)
Title :     VideoHandle
Language :  English
Encoded date :  UTC 2021-07-27 06:09:40
Tagged date :   UTC 2021-07-27 06:09:40
Color range :   Limited
Color primaries :   BT.709
Transfer characteristics :  BT.709
Matrix coefficients :   BT.709
mdhd_Duration :     37930
Codec configuration box :   hvcC

Audio
ID :    2
Format :    AAC LC
Format/Info :   Advanced Audio Codec Low Complexity
Codec ID :  mp4a-40-2
Duration :  37 s 909 ms
Bit rate mode :     Constant
Bit rate :  128 kb/s
Channel(s) :    2 channels
Channel layout :    L R
Sampling rate :     48.0 kHz
Frame rate :    46.875 FPS (1024 SPF)
Compression mode :  Lossy
Stream size :   592 KiB (1%)
Title :     SoundHandle
Language :  English
Encoded date :  UTC 2021-07-27 06:09:40
Tagged date :   UTC 2021-07-27 06:09:40