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Publier une image simplement
13 avril 2011, par ,
Mis à jour : Février 2012
Langue : français
Type : Video
Autres articles (58)
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Mediabox : ouvrir les images dans l’espace maximal pour l’utilisateur
8 février 2011, parLa visualisation des images est restreinte par la largeur accordée par le design du site (dépendant du thème utilisé). Elles sont donc visibles sous un format réduit. Afin de profiter de l’ensemble de la place disponible sur l’écran de l’utilisateur, il est possible d’ajouter une fonctionnalité d’affichage de l’image dans une boite multimedia apparaissant au dessus du reste du contenu.
Pour ce faire il est nécessaire d’installer le plugin "Mediabox".
Configuration de la boite multimédia
Dès (...) -
Publier sur MédiaSpip
13 juin 2013Puis-je poster des contenus à partir d’une tablette Ipad ?
Oui, si votre Médiaspip installé est à la version 0.2 ou supérieure. Contacter au besoin l’administrateur de votre MédiaSpip pour le savoir -
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 (12277)
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ffmpeg capture from ip camera video in h264 stream [closed]
23 mars 2023, par Иванов ИванI can't read the frames from the camera and then write them to a video file (any). The fact is that I even get crooked frames, they seem to have violated the coordinates of the position of each point, the video is crooked, distorted


c++ code.


https://drive.google.com/file/d/1W2sZMR5D5pvVmnhiQyhiaQhC9frhdeII/view?usp=sharing


#define INBUF_SIZE 4096


 //writing the minimal required header for a pgm file format
 //portable graymap format-> https://en.wikipedia.org/wiki/Netpbm_format#PGM_example
 fprintf (f, "P5\n%d %d\n%d\n", xsize, ysize, 255);

 //writing line by line
 for (i = 0; i /contains data on a configuration of media content, such as bitrate, 
 //frame rate, sampling frequency, channels, height and many other things.
 AVCodecContext * AVCodecContext_ = NULL;
 AVCodecParameters * AVCodecParametr_ = NULL;
 FILE * f;
 //This structure describes decoded (raw) audio- or video this.
 AVFrame * frame;
 uint8_t inbuf [INBUF_SIZE + AV_INPUT_BUFFER_PADDING_SIZE];
 uint8_t * data;
 size_t data_size;
 int ret;
 int eof;
 AVFormatContext * AVfc = NULL;
 int ERRORS;
 //AVCodec * codec;
 char buf [1024];
 const char * FileName;
 
 //https://habr.com/ru/post/137793/
 //Stores the compressed one shot.
 AVPacket * pkt;
 
 //**********************************************************************
 //Beginning of reading video from the camera. 
 //**********************************************************************
 
 avdevice_register_all ();
 
 filename = "rtsp://admin: 754HG@192.168.1.75:554/11";
 //filename = "c:\\1.avi";
 outfilename = "C:\\2.MP4";
 
 //We open a flow of video (it is the file or the camera). 
 ERRORS = avformat_open_input (& AVfc, filename, NULL, NULL);
 if (ERRORS <0) {
 fprintf (stderr, "ffmpeg: could not open file \n");
 return-1;
 }
 
 //After opening, we can print out information on the video file (iformat = the name of a format; 
 //duration = duration). But as I connected the camera to me wrote: Duration: N/A, 
 //start: 0.000000, bitrate: N/A
 printf ("Format %s, duration %lld us", AVfc-> iformat-> long_name, AVfc-> duration);
 
 
 ERRORS = avformat_find_stream_info (AVfc, NULL);
 if (ERRORS <0) {
 fprintf (stderr, "ffmpeg: Unable to find stream info\n");
 return-1;
 }
 
 
 int CountStream;
 
 //We learn quantity of streams. 
 CountStream = AVfc-> nb_streams;
 
 //Let's look for the codec. 
 int video_stream;
 for (video_stream = 0; video_stream nb_streams; ++ video_stream) {
 if (AVfc-> streams[video_stream]-> codecpar-> codec_type == AVMEDIA_TYPE_VIDEO) {
 break;
 }
 
 }
 
 if (video_stream == AVfc-> nb_streams) {
 fprintf (stderr, "ffmpeg: Unable to find video stream\n");
 return-1;
 }
 
 //Here we define a type of the codec, for my camera it is equal as AV_CODEC_ID_HEVC (This that in what is broadcast by my camera)
 codec = avcodec_find_decoder(AVfc-> streams [video_stream]-> codecpar-> codec_id);
 //--------------------------------------------------------------------------------------
 
 //Functions for inquiry of opportunities of libavcodec,
 AVCodecContext_ = avcodec_alloc_context3(codec);
 if (! AVCodecContext _) {
 fprintf (stderr, "Was not succeeded to allocate a video codec context, since it not poddrerzhivayetsya\n");
 exit(1);
 }
 
 //This function is used for initialization 
 //AVCodecContext of video and audio of the codec. The announcement of avcodec_open2 () is in libavcodecavcodec.h
 //We open the codec. 
 
 ERRORS = avcodec_open2 (AVCodecContext _, codec, NULL);
 if (ERRORS <0) {
 fprintf (stderr, "ffmpeg: It is not possible to open codec \n");
 return-1;
 }
 
 //It for processing of a sound - a reserve.
 //swr_alloc_set_opts ()
 //swr_init (); 
 
 //To output all information on the video file. 
 av_dump_format (AVfc, 0, argv[1], 0);
 
 //=========================================================================================
 //Further, we receive frames. before we only received all infomration about the entering video.
 //=========================================================================================
 
 //Now we are going to read packages from a stream and to decode them in shots, but at first 
 //we need to mark out memory for both components (AVPacket and AVFrame).
 frame = av_frame_alloc ();
 
 if (! frame) {
 fprintf (stderr, "Is not possible to mark out memory for video footage \n");
 exit(1);
 }
 //We mark out memory for a package 
 pkt = av_packet_alloc ();
 //We define a file name for saving the picture.
 const char * FileName1 = "C:\\Users\\Павел\\Desktop\\NyFile.PGM";
 //Data reading if they is. 
 while (av_read_frame (AVfc, pkt)> = 0) {
 //It is a package from a video stream? Because there is still a soundtrack.
 if (pkt-> stream_index == video_stream) {
 int ret;
 
 //Transfer of the raw package data as input data in the decoder
 ret = avcodec_send_packet (AVCodecContext _, pkt);
 if (ret <0 | | ret == AVERROR(EAGAIN) | | ret == AVERROR_EOF) {
 std:: cout <<"avcodec_send_packet:" <<ret while="while"> = 0) {
 
 //Returns the decoded output data from the decoder or the encoder
 ret = avcodec_receive_frame (AVCodecContext _, frame);
 if (ret == AVERROR(EAGAIN) | | ret == AVERROR_EOF) {
 //std:: cout <<"avcodec_receive_frame:" <<ret cout="cout"> of frame_number </============================================================================================
 
 //Experimentally - we will keep a shot in the picture. 
 
 save_gray_frame(frame-> data [0], frame-> linesize [0], frame-> width, frame-> height, (char *) FileName1);
 }
 }
 }
 
 //av_parser_close(parser);
 avcodec_free_context (& AVCodecContext _);
 av_frame_free (& frame);
 av_packet_free (& pkt);
 
 return 0;
</ret></ret>

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Evolution #3899 (Nouveau) : Comportement des inclusions avec le paramètre connect.
10 février 2017Il y a un comportement contre-intuitif dans un cas d’usage des inclusions et du paramètre connect, ce qu’à révélé une petite analyse dans #3823.
J’en fais un ticket dédié car c’est un problème distinct de ce qui est soulevé là bas.Fonctionnement actuel¶
Le paramètre d’URL
connect¶Le paramètre
connect=trucdans une URL d’un site SPIP permet d’indiquer à SPIP qu’il doit utilise le connecteur SQL ’truc’ dans les squelettes et les boucles utilisés,
et donc utiliserconfig/truc.phpen lieu et place deconfig/connect.php. À différents endroits du compilateur, ce paramètre est séparé du contexte d’environnement
du squelette, notamment dans les boucles où il atterrit dans$boucles[$idb]->sql_serveuret sera utilisé pour les requêtes SQL générées.Inclusions en indiquant un connect spécifique¶
Une autre manière d’indiquer que les squelettes / boucles utilisent un connecteur spécifique est de transmettre l’environnement
connect=trucaux inclusions, de la sorte :#INCLUREfond=test, connect=truc
Cette option d’inclusion est prise en compte dans
recuperer_fond().Inclusion
connect=trucet paramètre d’urlconnect=bidule¶Lorsqu’on a à la fois dans l’URL
&connect=bidule, et une inclusion qui indique un connect spécifique tel que#INCLURE{fond=test, connect=truc}
alors d’inclusion actuellement est chargée avec le paramètre d’URL, c’est à dire en utilisantconnect=bidule.
C’est cela qui est assez contre-intuitif et logiquement non désiré (le connect forcé ici devrait prendre le pas sur celui d’environnement).Comment améliorer ?¶
Où cela se passe dans le code ?¶
Ce qui se passe lorsqu’il y a cette écriture est, comme expliqué, que le connect dans l’URL reste prioritaire sur celui de l’argument transmis à
#INCLUREou<inclure></inclure>.- Pour #INCLURE ça se passe dans balise_INCLURE_dist() là https://core.spip.net/projects/spip/repository/entry/spip/ecrire/public/balises.php#L1995
- Pour
là ça se passe dans calculer_inclure() là https://core.spip.net/projects/spip/repository/entry/spip/ecrire/public/compiler.php#L169
Solutions ?¶
À ces 2 endroits, il faudrait du coup prendre en compte en priorité le
$contexte['connect']si existant- soit dans les 2 appels à la constante
CODE_RECUPERER_FONDplutôt que d’écrire directement_request('connect'), mais c’est un peu compliqué car c’est du code compilé - soit directement dans
recuperer_fond(), plus facile, inverser l’ordre :
if (isset($contexte[’connect’])) $connect = ($connect ? $connect : $contexte[’connect’]) ; unset($contexte[’connect’]) ;
deviendrait :if (isset($contexte[’connect’])) $connect = $contexte[’connect’] ; unset($contexte[’connect’]) ;
Cette dernière correction serait la plus simple et la plus facile. Ça permettrait même d’annuler un connect superieur dans une inclusion
en passant{connect=''}.Des avis ?
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How to contribute to open source, for companies
I have seen many nigh-incomprehensible attempts by companies to contribute to open source projects, including x264. Developers are often simply boggled, wondering why the companies seem incapable of proper communication. The companies assume the developers are being unreceptive, while the developers assume the companies are being incompetent, idiotic, or malicious. Most of this seems to boil down to a basic lack of understanding of how open source works, resulting in a wide variety of misunderstandings. Accordingly, this post will cover the dos and don’ts of corporate contribution to open source.
Do : contact the project using their preferred medium of communication.
Most open source projects use public methods of communication, such as mailing lists and IRC. It’s not the end of the world if you mistakenly make contact with the wrong people or via the wrong medium, but be prepared to switch to the correct one once informed ! You may not be experienced using whatever form of communication the project uses, but if you refuse to communicate through proper channels, they will likely not be as inclined to assist you. Larger open source projects are often much like companies in that they have different parts to their organization with different roles. Don’t assume that everyone is a major developer !
If you don’t know what to do, a good bet is often to just ask someone.
Don’t : contact only one person.
Open source projects are a communal effort. Major contributions are looked over by multiple developers and are often discussed by the community as a whole. Yet many companies tend to contact only a single person in lieu of dealing with the project proper. This has many flaws : to begin with, it forces a single developer (who isn’t paid by you) to act as your liaison, adding yet another layer between what you want and the people you want to talk to. Contribution to open source projects should not be a game of telephone.
Of course, there are exceptions to this : sometimes a single developer is in charge of the entirety of some particular aspect of a project that you intend to contribute to, in which case this might not be so bad.
Do : make clear exactly what it is you are contributing.
Are you contributing code ? Development resources ? Money ? API documentation ? Make it as clear as possible, from the start ! How developers react, which developers get involved, and their expectations will depend heavily on what they think you are providing. Make sure their expectations match reality. Great confusion can result when they do not.
This also applies in the reverse — if there’s something you need from the project, such as support or assistance with development of your patch, make that explicitly clear.
Don’t : code dump.
Code does not have intrinsic value : it is only useful as part of a working, living project. Most projects react very negatively to large “dumps” of code without associated human resources. That is, they expect you to work with them to finalize the code until it is ready to be committed. Of course, it’s better to work with the project from the start : this avoids the situation of writing 50,000 lines of code independently and then finding that half of it needs to be rewritten. Or, worse, writing an enormous amount of code only to find it completely unnecessary.
Of course, the reverse option — keeping such code to yourself — is often even more costly, as it forces you to maintain the code instead of the official developers.
Do : ignore trolls.
As mentioned above, many projects use public communication methods — which, of course, allow anyone to communicate, by nature of being public. Not everyone on a project’s IRC or mailing list is necessarily qualified to officially represent the project. It is not too uncommon for a prospective corporate contributor to be turned off by the uninviting words of someone who isn’t even involved in the project due to assuming that they were. Make sure you’re dealing with the right people before making conclusions.
Don’t : disappear.
If you are going to try to be involved in a project, you need to stay in contact. We’ve had all too many companies who simply disappear after the initial introduction. Some tell us that we’ll need an NDA, then never provide it or send status updates. You may know why you’re not in contact — political issues at the company, product launch crunches, a nice vacation to the Bahamas — but we don’t ! If you disappear, we will assume that you gave up.
Above all, don’t assume that being at a large successful company makes you immune to these problems. If anything, these problems seem to be the most common at the largest companies. I didn’t name any names in this post, but practically every single one of these rules has been violated at some point by companies looking to contribute to x264. In the larger scale of open source, these problems happen constantly. Don’t fall into the same traps that many other companies have.
If you’re an open source developer reading this post, remember it next time you see a company acting seemingly nonsensically in an attempt to contribute : it’s quite possible they just don’t know what to do. And just because they’re doing it wrong doesn’t mean that it isn’t your responsibility to try to help them do it right.
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