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Richard Stallman et le logiciel libre
19 octobre 2011, par
Mis à jour : Mai 2013
Langue : français
Type : Texte
Autres articles (112)
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Multilang : améliorer l’interface pour les blocs multilingues
18 février 2011, parMultilang est un plugin supplémentaire qui n’est pas activé par défaut lors de l’initialisation de MediaSPIP.
Après son activation, une préconfiguration est mise en place automatiquement par MediaSPIP init permettant à la nouvelle fonctionnalité d’être automatiquement opérationnelle. Il n’est donc pas obligatoire de passer par une étape de configuration pour cela. -
Des sites réalisés avec MediaSPIP
2 mai 2011, parCette page présente quelques-uns des sites fonctionnant sous MediaSPIP.
Vous pouvez bien entendu ajouter le votre grâce au formulaire en bas de page. -
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 (...)
Sur d’autres sites (9413)
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javacv FFMPEG decode memory leak ?
25 mars 2015, par Liquan NieI’m new to JAVACV and I am using FFMPEG to play some video file as follows
My enviroument is windows 8 with jdk7 and javacv0.10.String file_path ="D:\\1.mp4";
// regist all format and codec
avformat.av_register_all();
avcodec.avcodec_register_all();
// open file
avformat.AVFormatContext avFormatCtx = avformat.avformat_alloc_context();
if (avformat.avformat_open_input(avFormatCtx, file_path, null, null) != 0)
{
System.out.println("cann't open file\r\n");
return;
}
// find stream info
if (avformat.avformat_find_stream_info(avFormatCtx, (AVDictionary)null) < 0)
{
System.out.println("can't find stream info\r\n");
return;
}
int videoIndex = -1;
for(int i=0; i< avFormatCtx.nb_streams();i++)
{
if(avFormatCtx.streams(i).codec().codec_type() == avutil.AVMEDIA_TYPE_VIDEO)
{
videoIndex = i;
}
}
// determ codec
avcodec.AVCodecContext avCodecCtx = avFormatCtx.streams(videoIndex).codec();
avcodec.AVCodec codec = avcodec.avcodec_find_decoder(avCodecCtx.codec_id());
if (codec == null)
{
System.out.println("codec not found");
return;
}
if(avcodec.avcodec_open2(avCodecCtx, codec, (AVDictionary)null) < 0)
{
System.out.println("cann't open avcodec\r\n");
}
avutil.AVFrame frame = avcodec.avcodec_alloc_frame();
avutil.AVFrame frameRGB = avcodec.avcodec_alloc_frame();
int numByte = avcodec.avpicture_get_size(avutil.AV_PIX_FMT_RGB24, avCodecCtx.width(), avCodecCtx.height());
Pointer outBuffer = avutil.av_malloc(numByte);
avcodec.avpicture_fill(new AVPicture(frameRGB), outBuffer.asByteBuffer(), avutil.AV_PIX_FMT_RGB24, avCodecCtx.width(), avCodecCtx.height());
avformat.av_dump_format(avFormatCtx, 0, file_path, 0);
System.out.println(avFormatCtx.duration());
SwsContext img_convert_ctx = swscale.sws_getContext(avCodecCtx.width(), avCodecCtx.height(), avCodecCtx.pix_fmt(), avCodecCtx.width(), avCodecCtx.height(), avutil.AV_PIX_FMT_RGB24, swscale.SWS_BICUBIC, null, null, (double[])null);
AVPacket pkt = new AVPacket();
int y_size = avCodecCtx.width()*avCodecCtx.height();
avcodec.av_new_packet(pkt, y_size);
opencv_highgui.cvNamedWindow(WINDOW_NAME);
IplImage showImage = opencv_core.cvCreateImage(opencv_core.cvSize(avCodecCtx.width(), avCodecCtx.height()), opencv_core.IPL_DEPTH_8U, 3);
// read frames loop
int frameNumbers = avformat.av_read_frame(avFormatCtx, pkt);
System.out.println("frame number is "+frameNumbers);
while (avformat.av_read_frame(avFormatCtx, pkt) >= 0)
{
//System.out.println(pkt.asByteBuffer());
if (pkt.stream_index() == videoIndex)
{
IntPointer ip = new IntPointer();
int ret = avcodec.avcodec_decode_video2(avCodecCtx, frame, ip, pkt);
if (ret < 0)
{
System.out.println("codec error\r\n");
return;
}
if (ip.get()!= 0)
{
swscale.sws_scale(img_convert_ctx, frame.data(), frame.linesize(), 0, avCodecCtx.height(), frameRGB.data(), frameRGB.linesize());
showImage.imageData(frameRGB.data(0));
showImage.widthStep(frameRGB.linesize().get(0));
opencv_highgui.cvShowImage(WINDOW_NAME, showImage);
opencv_highgui.cvWaitKey(25);
}
}
}
showImage.release();
opencv_highgui.cvDestroyWindow(WINDOW_NAME);
avutil.av_free(frameRGB);
avcodec.avcodec_close(avCodecCtx);
avformat.avformat_close_input(avFormatCtx);but i run into get this error
# A fatal error has been detected by the Java Runtime Environment:
#
# EXCEPTION_ACCESS_VIOLATION (0xc0000005) at pc=0x00000000767c35ed, pid=11884, tid=3960
#
# JRE version: 7.0_13-b20
# Java VM: Java HotSpot(TM) 64-Bit Server VM (23.7-b01 mixed mode windows-amd64 compressed oops)
# Problematic frame:
# C [avcodec-56.dll+0x4835ed] avcodec_decode_video2+0xbd
#
# Failed to write core dump. Minidumps are not enabled by default on client versions of Windows
#
# An error report file with more information is saved as:
# E:\code\android\TestJAVACV\hs_err_pid11884.log
#
# If you would like to submit a bug report, please visit:
# http://bugreport.sun.com/bugreport/crash.jsp
# The crash happened outside the Java Virtual Machine in native code.
# See problematic frame for where to report the bug.
#
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'D:\1.mp4':
Metadata:
major_brand : isom
minor_version : 512
compatible_brands: isomiso2avc1mp41
creation_time : 1970-01-01 00:00:00
encoder : Lavf53.29.100
Duration: 00:08:30.27, start: 0.000000, bitrate: 160 kb/s
Stream #0:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 960x540 [SAR 1:1 DAR 16:9], 28 kb/s, 15 fps, 15 tbr, 15 tbn, 30 tbc (default)
Metadata:
creation_time : 1970-01-01 00:00:00
handler_name : VideoHandler
Stream #0:1(und): Audio: aac (LC) (mp4a / 0x6134706D), 44100 Hz, stereo, fltp, 127 kb/s (default)
Metadata:
creation_time : 1970-01-01 00:00:00
handler_name : SoundHandlerand in the log file i found that the enden space heap in jvm has been used 98%. but I don’t know where is the issue, since the document of ffmpeg is not that enough, I feel difficult to know more about how to use it well ,any suggestions ??
Heap
PSYoungGen total 23872K, used 20250K [0x00000000e5600000, 0x00000000e70a0000, 0x0000000100000000)
eden space 20480K, 98% used [0x00000000e5600000,0x00000000e69c69f8,0x00000000e6a00000) -
How to verify user permissions – Introducing the Piwik Platform
9 novembre 2014, 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 make your plugin multilingual). This time you’ll learn how to verify user permissions. For this tutorial you will need to have basic knowledge of PHP and the Piwik platform.
When should a plugin verify permissions ?
Usually you want to do this before executing any action – such as deleting or fetching data – and before rendering any sensitive information that should not be accessible by everyone. For instance in an API method or Controller action. You sometimes also need to verify permissions before registering menu items or widgets.
How does Piwik’s user management work ?
It is quite simple as it only differentiates between a few roles : View permission, Admin permission and Super User permission. If you manage multiple websites with Piwik a user can be assigned to different roles as a user might have no permission for some websites but view or admin permission for another set of websites.
Worth mentioning is that roles inherit from each other. This means the role admin automatically includes the role view and a super user automatically covers the view and admin role.
Getting started
In this post, we assume that you have already set up your development environment and created a plugin. If not, visit the Piwik Developer Zone where you’ll find the tutorial Setting up Piwik and other Guides that help you to develop a plugin.
Verifying user permissions
To protect your data the platform offers many convenient methods in the \Piwik\Piwik class. There you will find methods that either start with
check
,is
orhas
. While methods that start withcheck
throw an exception in case a condition is not met, the other methods return a booleantrue
orfalse
.Use methods that throw an exception if you want to stop any further execution in case a user does not have an appropriate role. The platform will catch the exception and display an error message or ask the user to log in.
- public function deleteAllMessages()
- {
- // delete messages only if user has super user access, otherwise show an error message
- Piwik::checkUserSuperUserAccess();
- $this->getModel()->deleteAllMessages();
- }
Use methods that return a boolean for instance when registering menu items or widgets.
- public function configureAdminMenu(MenuAdmin $menu)
- {
- if (Piwik::hasUserSuperUserAccess()) {
- $menu->addPlatformItem('Plugins', $this->urlForDefaultAction());
- }
- }
It is important to be aware that just because the menu item won’t be displayed in the UI a user can still open the registered URL manually. Therefore you have to check for permissions in the actual controller action as well.
View permission
A user having a view permission should be only able to view reports but not make any changes apart from his personal settings. The methods that end with
UserHasSomeViewAccess
make sure a user has at least view permission for one website whereas the methods*UserHasViewAccess($idSites = array(1,2,3))
check whether a user has view access for all of the given websites.- Piwik::checkUserHasSomeViewAccess();
As a plugin developer you would usually use the latter example to verify the permissions for specific websites. Use the first example in case you develop something like an “All Websites Dashboard” where you only want to make sure the user has a view permission for at least one website.
Admin permission
A user having an admin permission cannot only view reports but also change website related settings. The methods to check for this role are similar to the ones before, just swap the term
View
withAdmin
.- Piwik::checkUserHasSomeAdminAccess();
Super user permission
A user having the super user permission is allowed to access all of the data stored in Piwik and change any settings. To check if a user has this role use one of the methods that end with
UserSuperUserAccess
.Piwik::checkUserHasSuperUserAccess();
As a plugin developer you would check for this permission for instance in places where your plugin shows an activity log over all users or where it offers the possibility to change any system wide settings.
Getting information about the currently logged in user
Sometimes you might want to know which user is currently logged in. This can be useful if you want to persist user related information in the database or if you want to send an email to the currently logged in user. You can easily get this information by calling the following methods :
- $login = Piwik::getCurrentUserLogin()
- $email = Piwik::getCurrentUserEmail()
Advanced features
Of course there is more that you can do. For instance you can verify whether a user is an anonymous user or whether a user has a specific role. You can also perform any operation in the context of a super user even if the current user does not have this role. Would you like to know more about those features ? Check out the Piwik class reference, the Security guide and the Manage Users user guide.
If you have any feedback regarding our APIs or our guides in the Developer Zone feel free to send it to us.
-
How to verify user permissions – Introducing the Piwik Platform
9 novembre 2014, 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 make your plugin multilingual). This time you’ll learn how to verify user permissions. For this tutorial you will need to have basic knowledge of PHP and the Piwik platform.
When should a plugin verify permissions ?
Usually you want to do this before executing any action – such as deleting or fetching data – and before rendering any sensitive information that should not be accessible by everyone. For instance in an API method or Controller action. You sometimes also need to verify permissions before registering menu items or widgets.
How does Piwik’s user management work ?
It is quite simple as it only differentiates between a few roles : View permission, Admin permission and Super User permission. If you manage multiple websites with Piwik a user can be assigned to different roles as a user might have no permission for some websites but view or admin permission for another set of websites.
Worth mentioning is that roles inherit from each other. This means the role admin automatically includes the role view and a super user automatically covers the view and admin role.
Getting started
In this post, we assume that you have already set up your development environment and created a plugin. If not, visit the Piwik Developer Zone where you’ll find the tutorial Setting up Piwik and other Guides that help you to develop a plugin.
Verifying user permissions
To protect your data the platform offers many convenient methods in the \Piwik\Piwik class. There you will find methods that either start with
check
,is
orhas
. While methods that start withcheck
throw an exception in case a condition is not met, the other methods return a booleantrue
orfalse
.Use methods that throw an exception if you want to stop any further execution in case a user does not have an appropriate role. The platform will catch the exception and display an error message or ask the user to log in.
- public function deleteAllMessages()
- {
- // delete messages only if user has super user access, otherwise show an error message
- Piwik::checkUserSuperUserAccess();
- $this->getModel()->deleteAllMessages();
- }
Use methods that return a boolean for instance when registering menu items or widgets.
- public function configureAdminMenu(MenuAdmin $menu)
- {
- if (Piwik::hasUserSuperUserAccess()) {
- $menu->addPlatformItem('Plugins', $this->urlForDefaultAction());
- }
- }
It is important to be aware that just because the menu item won’t be displayed in the UI a user can still open the registered URL manually. Therefore you have to check for permissions in the actual controller action as well.
View permission
A user having a view permission should be only able to view reports but not make any changes apart from his personal settings. The methods that end with
UserHasSomeViewAccess
make sure a user has at least view permission for one website whereas the methods*UserHasViewAccess($idSites = array(1,2,3))
check whether a user has view access for all of the given websites.- Piwik::checkUserHasSomeViewAccess();
As a plugin developer you would usually use the latter example to verify the permissions for specific websites. Use the first example in case you develop something like an “All Websites Dashboard” where you only want to make sure the user has a view permission for at least one website.
Admin permission
A user having an admin permission cannot only view reports but also change website related settings. The methods to check for this role are similar to the ones before, just swap the term
View
withAdmin
.- Piwik::checkUserHasSomeAdminAccess();
Super user permission
A user having the super user permission is allowed to access all of the data stored in Piwik and change any settings. To check if a user has this role use one of the methods that end with
UserSuperUserAccess
.Piwik::checkUserHasSuperUserAccess();
As a plugin developer you would check for this permission for instance in places where your plugin shows an activity log over all users or where it offers the possibility to change any system wide settings.
Getting information about the currently logged in user
Sometimes you might want to know which user is currently logged in. This can be useful if you want to persist user related information in the database or if you want to send an email to the currently logged in user. You can easily get this information by calling the following methods :
- $login = Piwik::getCurrentUserLogin()
- $email = Piwik::getCurrentUserEmail()
Advanced features
Of course there is more that you can do. For instance you can verify whether a user is an anonymous user or whether a user has a specific role. You can also perform any operation in the context of a super user even if the current user does not have this role. Would you like to know more about those features ? Check out the Piwik class reference, the Security guide and the Manage Users user guide.
If you have any feedback regarding our APIs or our guides in the Developer Zone feel free to send it to us.