
Recherche avancée
Médias (1)
-
Bug de détection d’ogg
22 mars 2013, par
Mis à jour : Avril 2013
Langue : français
Type : Video
Autres articles (105)
-
Support audio et vidéo HTML5
10 avril 2011MediaSPIP utilise les balises HTML5 video et audio pour la lecture de documents multimedia en profitant des dernières innovations du W3C supportées par les navigateurs modernes.
Pour les navigateurs plus anciens, le lecteur flash Flowplayer est utilisé.
Le lecteur HTML5 utilisé a été spécifiquement créé pour MediaSPIP : il est complètement modifiable graphiquement pour correspondre à un thème choisi.
Ces technologies permettent de distribuer vidéo et son à la fois sur des ordinateurs conventionnels (...) -
HTML5 audio and video support
13 avril 2011, parMediaSPIP uses HTML5 video and audio tags to play multimedia files, taking advantage of the latest W3C innovations supported by modern browsers.
The MediaSPIP player used has been created specifically for MediaSPIP and can be easily adapted to fit in with a specific theme.
For older browsers the Flowplayer flash fallback is used.
MediaSPIP allows for media playback on major mobile platforms with the above (...) -
De l’upload à la vidéo finale [version standalone]
31 janvier 2010, parLe chemin d’un document audio ou vidéo dans SPIPMotion est divisé en trois étapes distinctes.
Upload et récupération d’informations de la vidéo source
Dans un premier temps, il est nécessaire de créer un article SPIP et de lui joindre le document vidéo "source".
Au moment où ce document est joint à l’article, deux actions supplémentaires au comportement normal sont exécutées : La récupération des informations techniques des flux audio et video du fichier ; La génération d’une vignette : extraction d’une (...)
Sur d’autres sites (11722)
-
How to expose new API methods in the HTTP Reporting API – Introducing the Piwik Platform
26 février 2015, par Thomas Steur — DevelopmentThis is the next post of our blog series where we introduce the capabilities of the Piwik platform (our previous post was How to write UI tests for your plugin). This time you’ll learn how to extend our Reporting API. For this tutorial you will need to have basic knowledge of PHP.
What is Piwik’s Reporting API ?
It allows third party applications to access analytics data and manipulate miscellaneous data (such as users or websites) through HTTP requests.
What is it good for ?
The Reporting API is used by the Piwik UI to render reports, to manage users, and more. If you want to add a feature to the Piwik UI, you might have to expose a method in the API to access this data. As the API is called via HTTP it allows you to fetch or manipulate any Piwik related data from anywhere. In these exposed API methods you can do pretty much anything you want, for example :
- Enhance existing reports with additional data
- Filter existing reports based on custom rules
- Access the database and generate custom reports
- Persist and read any data
- Request server information
Getting started
In this series of posts, we assume that you have already set up your development environment. If not, visit the Piwik Developer Zone where you’ll find the tutorial Setting up Piwik.
To summarize the things you have to do to get setup :
- Install Piwik (for instance via git).
- Activate the developer mode :
./console development:enable
. - Generate a plugin :
./console generate:plugin --name="MyApiPlugin"
. There should now be a folderplugins/MyApiPlugin
. - And activate the created plugin :
./console plugin:activate "MyApiPlugin"
Let’s start creating an API
We start by using the Piwik Console to create a new API :
./console generate:api
The command will ask you to enter the name of the plugin the created API should belong to. I will simply use the above chosen plugin name “MyApiPlugin”. There should now be a file
plugins/MyApiPlugin/API.php
which contains already an example to get you started easily :- class API extends \Piwik\Plugin\API
- {
- public function getAnswerToLife($truth = true)
- {
- if ($truth) {
- return 42;
- }
- return 24;
- }
- public function getExampleReport($idSite, $period, $date, $wonderful = false)
- {
- ));
- return $table;
- }
- }
Any public method in that file will be available via the Reporting API. For example the method
getAnswerToLife
can be called via this URL :index.php?module=API&method=MyApiPlugin.getAnswerToLife
. The URL parametermethod
is a combination of your plugin name and the method name within this class.Passing parameters to your method
Both example methods define some parameters. To pass any value to a parameter of your method simply specify them by name in the URL. For example
...&method=MyApiPlugin.getExampleReport&idSite=1&period=week&date=today&wonderful=1
to pass values to the parameters of the methodgetExampleReport
.Returning a value
In an API method you can return any boolean, number, string or array value. A resource or an object cannot be returned unless it implements the DataTableInterface such as DataTable (the primary data structure used to store analytics data in Piwik), DataTable\Map (stores a set of DataTables) and DataTable\Simple (a DataTable where every row has two columns : label and value).
Did you know ? You can choose the response format of your API request by appending a parameter
&format=JSON|XML|CSV|...
to the URL. Check out the Reporting API Reference for more information.Best practices
Check user permissions
Do not forget to check whether a user actually has permissions to access data or to perform an action. If you’re not familiar with Piwik’s permissions and how to check them read our User Permission guide.
Keep API methods small
At Piwik we aim to write clean code. Therefore, we recommend to keep API methods small (separation of concerns). An API pretty much acts like a Controller :
- public function createLdapUser($idSite, $login, $password)
- {
- Piwik::checkUserHasAdminAccess($idSite);
- $this->checkLogin($login);
- $this->checkPassword($password);
- $myModel = new LdapModel();
- $success = $myModel->createUser($idSite, $login, $password);
- return $success;
- }
This is not only easy to read, it will also allow you to create simple tests for
LdapModel
(without having to bootstrap the whole Piwik layer) and you will be able to reuse it in other places if needed.Calling APIs of other plugins
For example if you want to fetch an existing report from another plugin, say a list of all Page URLs, do not request this report by calling that method directly :
\Piwik\Plugins\Actions\API::getInstance()->getPageUrls($idSite, $period, $date);
. Instead, issue a new API request :
$report = \Piwik\API\Request::processRequest('Actions.getPageUrls', array(
'idSite' => $idSite,
'period' => $period,
'date' => $date,
));This has several advantages :
- It avoids a fatal error if the requested plugin is not available on a Piwik installation
- Other plugins can extend the called API method via events (adding additional report data to a report, doing additional permission checks) but those events will be only triggered when requesting the report as suggested
- If the method parameters change, your request will most likely still work
Publishing your Plugin on the Marketplace
In case you want to share your API with other Piwik users you can do this by pushing your plugin to a public GitHub repository and creating a tag. Easy as that. Read more about how to distribute a plugin and best practices when publishing a plugin.
Isn’t it easy to create a API ? We never even created a file ! If you have any feedback regarding our APIs or our guides in the Developer Zone feel free to send it to us.
-
Encode Frames to Video with C Library
31 juillet 2018, par NetherGraniteFor the sake of continuity, let us assume "RGB values" are the following :
typedef struct RGB {
uint8_t r, g, b;
} rgb;However, if you feel that a different color space is more appropriate for this question, please use that instead.
How might I go about writing 2D arrays of RGB values to a video in C given an output format and framerate ?
Before I continue, I should specify that I wish to be able to do this all within one program. I am trying to add functionality to an application that would allow it to compile videos frame by frame without having to leave it.
Additionally, my needs for this functionality are extremely basic ; I simply need to be able to set individual pixels to certain colors.
The closest I have come to a solution so far is the C library FFmpeg. Allow me to describe what I was able to learn on my own :
After looking through its documentation, I came across the function
avcodec_send_frame(avctx, frame)
, whose parameters are of the typesAVCodexContext*
andconst AVFrame*
respectively. If these are not the right tools for what I am trying to do, please ignore the rest of the question and instead point me towards what I should be using.However, I do not know which fields of
avctx
andframe
must be set manually and which do not. The reason I assume some do not is because both are extremely large structures, but correct me if I am wrong.Question 1 : What values of an
AVCodecContext
andAVFrame
must be set ? Of these, what is/are the recommended value(s) for each of them ?Additionally, I was only able to find instructions on how to initialize an
AVFrame
(usingav_frame_alloc()
andav_frame_get_buffer()
) but not for anAVCodexConstant
.Question 2 : Is there a proper way to initialize an
AVCodexConstant
? And just in case, is the method of initializing anAVFrame
described above correct ? Do any of the fields of either have a proper method of initialization ?Also, I was not able to find official documentation on how to take this
AVCodexConstant
(which I assume contains the video information) and turn it into a video. I apologize if the documentation for this is easy to find and I just missed it.Question 3 : How do I turn an
AVCodexConstant
into a file of a given format ?And, given my limited knowledge :
Question 4 : Are there any other parts to this process that I am missing, and do I have any of the above parts wrong ?
Please keep in mind that I found out about FFmpeg for the first time very recently, and as a result, I am a complete beginner to this. Additionally, my experience with C is very limited, so I would greatly appreciate it if you could note which files need to be included with
#include
.Feel free to even go as far as recommending something other than FFmpeg, just as long as it is written in C. I do not need power-user options, but I would greatly prefer flexibility in what audio and video file types the library can handle.
Addressing Potential Duplicates
I appologize for how long this section is ; I just want to have my bases covered. I heavily apologize, however, if this is in fact a duplicate of a question that I was just unable to find.
- ffmpeg C API documentation/tutorial [closed] — This question was too open-ended and received answers pointing the asker towards a tutorial at dranger.com, a tutorial that confusingly muddied the waters by focusing heavily on a graphics library of choice. Please do not take this as me saying it is bad ; I am just enough of a beginner that I could not wade through it all.
- Encoding frames to video with ffmpeg — Although this question seems to have been asking the same thing, it is geared towards Unreal Engine 4, and the asker provided sample code, making it difficult for me to understand which of parts of the accepted answer were necessary for me and which were not.
- How to write frames to a video file ? — While this also asked the same thing, the accepted answer simply provides a command instead of an explanation of code.
- YUV Raw frames to video stream — While the accepted answer for this question is a command, the question states that it is looking for a way to encode frames generated by C++ code. Is there some way to run commands in code that I haven’t been able to find ?
- Converting sequenced frames to video — Not only is the asker’s code written in Python, but it also seems to use already-existing image files as frames.
- How to write bitmaps as frames to H.264 with x264 in C\C++ ? — The accepted answer seems to describe a process that would take multiple applications, but I could be wrong as I am enough of a beginner that I am not sure exactly what it means other than Step 3.
- How to write bitmaps as frames to Ogg Theora in C\C++ ? — Although it isn’t a problem that the question specifies the ogg format, it is a problem that the accepted answer suggests libtheora, which appears to only work with ogg files.
-
A Comprehensive Guide to Robust Digital Marketing Analytics
15 novembre 2023, par Erin — Analytics Tips