Extension:PageImages/pt

From MediaWiki.org
Jump to navigation Jump to search
This page is a translated version of the page Extension:PageImages and the translation is 2% complete.

Other languages:
English • ‎polski • ‎português • ‎русский • ‎中文 • ‎日本語
Manual de extensões do MediaWiki
OOjs UI icon advanced.svg
PageImages
Estado da versão: estável
Implementação API , Parser extension
Descrição Stores information about images representing a page
Autor(es) Max Semenik (MaxSemtalk)
Última versão continuous updates
Normas de
compatibilidade
ramos de lançamentos
MediaWiki 1.25+
PHP 5.4+
Alterações à
base de dados
Não
Licença WTFPL 2.0
Exportação (Download)

  • $wgPageImagesBlacklist
  • $wgPageImagesBlacklistExpiry
  • $wgPageImagesExpandOpenSearchXml
  • $wgPageImagesNamespaces
Traduza a extensão PageImages se ela estiver disponível na wiki translatewiki.net
Verifique a matriz de utilização e versões
Problemas Tarefas em aberto · Reportar um problema

The PageImages extension collects information about images used on a page.

Its aim is to return the single most appropriate thumbnail associated with an article.

Since MediaWiki 1.29, PageImages provides OpenGraph protocol metadata for articles on the wiki for 3rd parties like Facebook to extract.

Installation

  • Exporte e coloque o ficheiro, ou ficheiros, num diretório chamado PageImages, na sua pasta extensions/.
  • Acrescente o seguinte código ao fundo do ficheiro LocalSettings.php:
    wfLoadExtension( 'PageImages' );
    
  • Yes Pronto – Na página especial Special:Version da sua wiki verifique se a extensão foi instalada.

Para utilizadores que tenham o MediaWiki versão 1.27 ou anteriores:

As instruções acima descrevem a nova forma de instalar esta extensão, usando a extensão wfLoadExtension() Se precisar de instalar esta extensão nestas versões anteriores (MediaWiki 1.27 e anteriores), em vez de wfLoadExtension( 'PageImages' );, use:

require_once "$IP/extensions/PageImages/PageImages.php";

API

The PageImages extension provides image information by adding a prop=pageimages to the properties API for action=query.

prop=pageimages (pi)

(main | query | pageimages)
  • This module requires read rights.
  • Source: PageImages
  • License: WTFPL

Returns information about images on the page, such as thumbnail and presence of photos.

Parameters:
piprop

Which information to return:

thumbnail
URL and dimensions of thumbnail image associated with page, if any.
original
URL and original dimensions of image associated with page, if any.
name
Image title.
Values (separate with | or alternative): thumbnail, name, original
Default: thumbnail|name
pithumbsize

Maximum width in pixels of thumbnail images.

Type: integer
Default: 50
pilimit

Properties of how many pages to return.

No more than 50 (100 for bots) allowed.
Type: integer or max
Default: 50
pilicense

Limit page images to a certain license type

One of the following values: free, any
Default: free
picontinue

When more results are available, use this to continue.

Type: integer
Example:
Get name and 100-pixel thumbnail of an image on the Albert Einstein page.
api.php?action=query&prop=pageimages&titles=Albert%20Einstein&pithumbsize=100 [open in sandbox]

Response

{
  // piprop.name (and image exists)
  pageimage?: string // Source image filename (basename of original.source).
  // piprop.thumbnail (and image exists)
  thumbnail?: {
    source: string // Thumbnail image URL.
    width: number // Thumbnail image width in pixels.
    height: number // Thumbnail image height in pixels.
  }
  // piprop.original (and image exists)
  original?: {
    source: string // Source image URL.
    width: number // Source image width in pixels.
    height: number // Source image height in pixels.
  }
}

Sample request

Request page image for an article.

Configuration

$wgPageImagesBlacklist is an array of sources for image blacklists. Blacklisted images will never be selected as page images. Examples:

$wgPageImagesBlacklist = array(
	// Page on local wiki
	array(
		'type' => 'db',
		'page' => 'MediaWiki:Pageimages-blacklist',
		'db' => false,
	),
	// Page on Wikimedia Commons, for other Wikimedia projects using direct DB access
	array(
		'type' => 'db',
		'page' => 'MediaWiki:Pageimages-blacklist',
		'db' => 'commonswiki',
	),
	// Page on Commons, for third-party sites using web access
	array(
		'type' => 'url',
		'url' => 'http://commons.wikimedia.org/w/index.php?title=somepage&action=raw',
	),
);

More than one source can be used at the same time.

The blacklist itself should contain a wikilinks to blacklisted files, the rest of content is irrelevant (and can contain links to other pages). For example:

* [[:File:First blacklisted file.png]]
* [[:File:Second blacklisted file.jpeg]]
...

Remember that file links that result in images being added to the page will not work (these files are blacklisted for a reason, right?), so don't forget the : in front of the links.

$wgPageImagesBlacklistExpiry determines how long the blacklist will remain cached, in seconds. Default: 15 * 60 (15 minutes).

$wgPageImagesExpandOpenSearchXml if set to true, PageImages will override the image detection in the opensearch API module with its own, more accurate results. Default: false.

$wgPageImagesNamespaces is an array of namespaces PageImages will be activated on. Default: NS_MAIN.

How it works

When a page is saved with a local image, the parser runs the hooks ParserMakeImageParams and LinksUpdate. The PageImages extension responds to these (and other hooks) and inserts a new property for the page into the page_props table. The property name is page_image and its value is the name of the image.

The extension only stores the chosen image name. Other features may display the image, such as Page information, Hovercards, and Mobile search while typing.

Image choice

How can I check which image is associated with a page?

Page images will be listed on the ?action=info page.

How does it select images?

All images in the page are collected and a score for each image is calculated. The image with the highest score is selected as the page image. If the wiki is configured such that images contain metadata that specifies images are not freely licensed, the image with the best score that is also freely licensed is also stored. If no suitable image is found or all the images score badly (i.e. has a negative score), the page will not have any images.

If $wgPageImagesLeadSectionOnly is true, only images in the lead section will be considered. Currently it is true for only Wikipedia projects, all other projects can pull images from outside the lead.

How are images scored?

The best possible page image on Wikimedia wikis is one of the first four images in an article which has a width/height between 400-600px and a height/width which is twice the value of the other dimension.

  • The algorithm is configurable.
  • Scores are calculated by a combination of:
    • Image widths as defined in $wgPageImagesScores['width']
      • In Wikimedia wikis, images smaller than 119 pixels are weighted highly negatively. Images with widths between 400px-600px are favoured, with a preference for the lower bound.
      • Images inside galleries are scored separately using $wgPageImagesScores['galleryImageWidth']
        • In Wikimedia wikis gallery images which are smaller than 100 are disregarded.
    • Position in document is also considered as defined in $wgPageImagesScores['position']
      • On Wikimedia wikis, only the first 4 images that appear in the document are considered.
    • The ratio of the image's width to height is considered $wgPageImagesScores['ratio']
      • On Wikimedia wikis the best possible images are images where the height is half the width or the height is double the width. Any images for which the ratio is less than 0.5 will score negatively and be discarded.

Be more technical please...

Pageimages populates images whenever the LinksUpdate hook runs.

In PageImages this is executed in LinksUpdateHookHandler::doLinksUpdate

Can I exclude certain page images?

Yes! There is a blacklist on every wiki that administrators can edit, at MediaWiki:Pageimages-blacklist (example). Any images that appear here will not be page images for any article.

What about just for one particular article?

Sadly not at the current time. Please use the blacklist or move the image outside the lead section.

How can I see the page image for a page?

Using the Informações da página link in the sidebar (or adding ?action=info to the URL) you'll be able to see the current image choice.

How can I purge a bad image?

The pageimage only changes when a link in an article changes. For emergencies, please add/remove links from the page, reverting if necessary. Purging will not work. For larger emergencies please file a Phabricator ticket.

Why is my page image a blank box?

This likely relates to video content in your article. If a video file begins with a blank screen, that will become the default thumbnail for the video and if used as the page image, it will become the page image. We are currently working on a fix for this, that will allow you to change the default thumbnail of a video. See: phab:T92457 and phab:T22647 for further information.

Ver também