Help:Images

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This page explains the image syntax when editing the wiki. You or another user must usually upload an image before you can use it on a page.

Images that are stored on a MediaWiki server are usually rendered by using the File: namespace prefix (but the legacy Image: namespace prefix is still supported as a synonym) as the target of a MediaWiki link. The alternate Media: namespace prefix is also usable to reference the original media file content (for rendering or downloading it separately, out of any MediaWiki page).

Supported media types for images

The following file formats are supported by default:

  • .jpg or .jpeg : bitmap image compressed in the standard JPEG format (this lossy format is most suitable for photographs).
  • .png : bitmap image in the Portable Network Graphics format (specified by the W3 Consortium).
  • .gif : bitmap image in the legacy Graphics Interchange Format.

Other formats used on Wikimedia, and commonly enabled elsewhere (these may require extra set-up beyond what is enabled by default):

  • .svg : scalable image in the Scalable Vector Graphics format (specified by the W3 Consortium). See Manual:Image_Administration#SVG.
  • .tiff : Tagged image format. Often used for high-resolution archival photographs. Often used with Extension:PagedTiffHandler.
  • .ogg, .oga, .ogv : Ogg multimedia (audio or video) Not an image format, but treated similarly. Often used with Extension:OggHandler
  • .pdf : multipaged documents in the Portable Document Format (initially specified by Adobe). Often used in conjunction with Extension:PdfHandler
  • .djvu : multipaged bitmap documents in the DejaVu format (most often, scans of books). See Manual:How to use DjVu with MediaWiki
    Only a single page of a .pdf or .djvu file is shown at one time.

Other media types may be supported, but it may not be possible to display them inline.

Rendering a single image

Syntax

The full syntax for displaying an image is:

[[File:filename.extension|options|caption]]

where options can be zero or more of the following, separated by pipes (|):

  • Format option: one of border and/or frameless, frame, thumb (or thumbnail);
    Controls how the rendered image is formatted and embedded in the rest of the page.
  • Resizing option: one of
    • {width}px — Resizes the image to fit within the given maximum width in pixels, without restricting its height;
    • x{height}px — Resizes the image to fit within the given maximum height in pixels, without restricting its width;
    • {width}x{height}px — Resizes the image to fit within the given width and height in pixels;
    • upright — Resizes an image to fit within reasonable dimensions, according to user preferences (suitable for images whose height is larger than width).
    Note that the image will always retain its aspect ratio, and can only be reduced (not increased) in size unless it's in a scalable media type (bitmap images cannot be scaled up).
    The default maximum size depends on the format and the internal image dimensions (according to its media type).
  • Horizontal alignment option: one of left, right, center, none;
    Controls the horizontal alignment (and inline/block or floating styles) of the image within a text (no default value).
  • Vertical alignment option: one of baseline, sub, super, top, text-top, middle, bottom, text-bottom;
    Controls the vertical alignment of a non-floating inline image with the text before or after the image, and in the same block (the default vertical alignment is middle).
  • Link option: one of
    • link={target} — Allows to change the target (to an arbitrary page title, or URL) of the generated link, activable on the rendered image surface; e.g. [[File:Example.jpg|20px|link=http://www.wikipedia.org]] renders as Example.jpg (external link), or [[File:Example.jpg|20px|link=MediaWiki]] renders as Example.jpg (internal link).
    • link= (with an empty value) — (MediaWiki 1.14+) Displays an image without any activable link; e.g. [[File:Example.jpg|20px|link=]] renders as Example.jpg.
      • ! If you set |link=| (empty), then no title will be rendered. (see bugzilla:21454)
  • Other specific options:
    • alt={alternative text} — (MediaWiki 1.14+) Defines the alternative text (maps to the HTML attribute alt="..." of the generated <img /> element) of an image that will be rendered if either the referenced image cannot be downloaded and embedded, or if the support media must use the alternative description text (e.g. when using a Braille reader or with accessibility options set by the user in its browser).
    • page={number} — Renders the specified page number (currently only applicable when showing a .djvu or .pdf file).
    • class={html class} — (MediaWiki 1.20+) Defines classes (maps to the HTML attribute class="..." of the generated <img /> element)

If a parameter does not match any of the other possibilities, it is assumed to be the caption text. Caption text only shows below the image in thumb and frame formats. Caption text displayed in the thumb and frame formats may contain wiki links and other formatting. In the other options, wiki-formatting will not work though transclusion will.

Format

The following table shows the effect of all available formats.

When the height of an image in thumbnail is bigger than its width (i.e. in portrait orientation rather than landscape) and you find it too large, you may try the option upright, which will try to adjust its size to a more desirable size by reducing the height instead of the width. The alternative is to specify the desired maximum height (in pixels) explicitly.

Note that by writing thumb={filename}, you can use a different image for the thumbnail.

Size and frame

Among different formats, the effect of the size parameter may be different, as shown below.

  • For how it appears when its size is not specified, see Format section above.
  • When the format is not specified, or only bordered, the size can be both reduced and enlarged to any specified size.
  • In the examples below, the original size of the image is 400 × 267 pixels.
  • An image with frame always ignores the size specification, the original image will be reduced if it exceeds the maximum size defined in user preferences.
  • The size of an image with thumb can be reduced, but can not be enlarged beyond the original size of the image.
Format Reduced Enlarged
(not specified)
[[File:MediaWiki:Image sample|50px]]

[[File:MediaWiki:Image sample||50px]]

[[File:MediaWiki:Image sample|500px]]

[[File:MediaWiki:Image sample||500px]]


border
[[File:MediaWiki:Image sample|border|50px]]

[[File:MediaWiki:Image sample|border|50px]]

[[File:MediaWiki:Image sample|border|500px]]

[[File:MediaWiki:Image sample|border|500px]]


frame
[[File:MediaWiki:Image sample|frame|50px]]

[[File:MediaWiki:Image sample|frame|50px]]

[[File:MediaWiki:Image sample|frame|500px]]

[[File:MediaWiki:Image sample|frame|500px]]


thumb
[[File:MediaWiki:Image sample|thumb|50px]]

[[File:MediaWiki:Image sample|thumb|50px]]

[[File:MediaWiki:Image sample|thumb|500px]]

[[File:MediaWiki:Image sample|thumb|500px]]


frameless
[[File:MediaWiki:Image sample|frameless|50px]]

[[File:MediaWiki:Image sample|frameless|50px]]

[[File:MediaWiki:Image sample|frameless|500px]]

[[File:MediaWiki:Image sample|frameless|500px]]

Horizontal alignment

Note that when using the frame or thumb[nail] formats, the default horizontal alignment will be right.

Description You type You get
no horizontal alignment specified, or default alignment
Rendered as a floating block: no
Rendered inline: yes
... text text text
[[File:example.jpg|100px|caption]]
text text text ...
... text text text

caption text text text ...

specify horizontal alignment as: none
Rendered as a floating block: no
Rendered inline: no
... text text text
[[File:example.jpg|none|100px|caption]]
text text text ...
... text text text
caption

text text text ...

specify horizontal alignment as: center
Rendered as a floating block: no
Rendered inline: no
... text text text
[[File:example.jpg|center|100px|caption]]
text text text ...
... text text text
caption

text text text ...

specify horizontal alignment as: left
Rendered as a floating block: yes
Rendered inline: no
... text text text
[[File:example.jpg|left|100px|caption]]
text text text ...
... text text text
caption

text text text ...

specify horizontal alignment as: right
Rendered as a floating block: yes
Rendered inline: no
... text text text
[[File:example.jpg|right|100px|caption]]
text text text ...
... text text text
caption

text text text ...

Vertical alignment

The vertical alignment options take effect only if the image is rendered as an inline element and is not floating. They alter the way the inlined image will be vertically aligned with the text present in the same block before and/or after this image on the same rendered row.

Note that the rendered line of text where inline images are inserted (and the lines of text rendered after the current one) may be moved down (this will increase the line-height conditionally by additional line spacing, just as it may occur with spans of text with variable font sizes, or with superscripts and subscripts) to allow the image height to be fully displayed with this alignment constraint.

Toggle source code view

<source lang="html4strict" enclose="div">

text top: Example.jpg Example.jpg Example.jpg text

text text-top: Example.jpg Example.jpg Example.jpg text

text super: Example.jpg Example.jpg Example.jpg text

text baseline: Example.jpg Example.jpg Example.jpg text

text sub: Example.jpg Example.jpg Example.jpg text

text default: Example.jpgExample.jpg Example.jpg text

text middle: Example.jpg Example.jpg Example.jpg text

text text-bottom: Example.jpg Example.jpg Example.jpg text

text 'bottom: Example.jpg Example.jpg Example.jpg text

</source>

To show the alignment result more clearly, the text spans are overlined and underlined, the font-size is increased to 200%, and the paragraph block is outlined with a thin border; additionally images of different sizes are aligned:

text top: Example.jpg Example.jpg Example.jpg text

text text-top: Example.jpg Example.jpg Example.jpg text

text super: Example.jpg Example.jpg Example.jpg text

text baseline: Example.jpg Example.jpg Example.jpg text

text sub: Example.jpg Example.jpg Example.jpg text

text default: Example.jpg Example.jpg Example.jpg text

text middle: Example.jpg Example.jpg Example.jpg text

text text-bottom: Example.jpg Example.jpg Example.jpg text

text bottom: Example.jpg Example.jpg Example.jpg text

Notes:

  1. The "middle" vertical alignment position of the image (which is also the default) usually refers to the middle between the x-height and the baseline of the text (on which the vertical middle of the image will be aligned, and on which usually the text may be overstroke), but not to the middle of the line-height of the font-height that refers to the space between the "text-top" and "text-bottom" positions ; the font-height excludes:
    • the additional line separation spacing normally divided equally into two line-margins (here 0.5em, according to line-height set to 200%) above and below the font-height).
    • the additional line spacing which may be added by superscripts and subscripts.
  2. However, if the image height causes its top or bottom position to go above or below the normal full line-height of text, the middle position will be adjusted after the increasing the top and/or bottom line-margins so that the image can fit and align properly, and all images (including those with smaller heights) will be vertically centered on the adjusted middle position (for computing the effective line-height, the text of each rendered row with the larger font-height will be considered).
  3. The "text-top" and "text-bottom" alignment positions also excludes the extra line spacing added by superscripts and subscripts, but not the additional line-spacing defined by the line-height.
  4. The "top" and "bottom" alignment positions take into account all these extra line spacings (including superscripts and subscripts, if they are present in a rendered line span). When the image alignment constrains the image to grow above or below the normal line-spacing, and the image is not absolutely positioned, the image will cause the "top" and "bottom" positions to be adjusted (just like superscripts and subscripts), so the effective line-height between rendered lines of text will be higher.
  5. The "underline", "overline" and "overstrike" text-decoration positions should be somewhere within these two limits and may depend on the type and height of fonts used (the superscript and subscript styles may be taken into account in some browsers, but usually these styles are ignored and the position of these decorations may not be adjusted); so these decorations normally don't affect the vertical position of images, relatively to the text.

Stopping the text flow

On occasion it is desirable to stop text (or other inline non-floating images) from flowing around a floating image. Depending on the web browser's screen resolution and such, text flow on the right side of an image may cause a section header (for instance, == My Header ==) to appear to the right of the image, instead of below it, as a user may expect. The text flow can be stopped by placing <br clear=all> (or if you prefer, <div style="clear: both"></div>) before the text that should start below the floating image. (This may also be done without an empty line by wrapping the section with the floating images with <div style="overflow: hidden">…</div>, which clears all floats inside the div element.)

All images rendered as blocks (including non-floating centered images, left- or right-floating images, as well as framed or thumbnailed floating images) are implicitly breaking the surrounding lines of text (terminating the current block of text before the image, and creating a new paragraph for the text after them). They will then stack vertically along their left or right alignment margin (or along the center line between these margins for centered images).

Altering the default link target

The following table shows how to alter the link target (whose default is the image description page) or how to remove it. Changing the link does not alter the format described in the previous sections.

Warning:

The licencing requirements on your wiki may not allow you to remove all links to the description page that displays the required authors attributions, the copyrights statements, the applicable licencing terms, or a more complete description of the rendered image (including its history of modifications).
If you change or remove the target link of an image, you will then have to provide somewhere else on your page an explicit link to this description page, or to display the copyright and author statement and a link to the applicable licence, if they are different from the elements applicable to the embedding page itself.
Your wiki policy may restrict the use of the alternate link parameter, or may even enforce a prohibition of alternate link parameters for embedded media files (in which case, the link parameter will be ignored), or may only accept them after validation by authorized users or administrators.

Rendering a gallery of images

Gallery syntax

It's easy to make a gallery of thumbnails with the <gallery> tag. The syntax is:

<gallery>
File:file_name.ext|caption|alt=alt language
File:file_name.ext|caption|alt=alt language
{...}
</gallery>

Note that the image code is not enclosed in brackets when enclosed in gallery tags.

Captions are optional, and may contain wiki links or other formatting. Some of the parameters controlling thumb output can also be used here, specifically the one's that modify the file (as opposed to one's that control where in the page the image falls). For example, with multi-paged media like pdfs, you can use code like page=4.

The File: prefix can be omitted.

for example:

<gallery>
File:Example.jpg|Item 1
File:Example.jpg|a link to [[Help:Contents]]
File:Example.jpg
File:Example.jpg|alt=An example image. It has flowers
File:Example.jpg| ''italic caption''
File:Example.jpg|on page "{{PAGENAME}}"
</gallery>

is formatted as:

mode parameter

MediaWiki version: = 1.22Template:MW version/list1 and greater

Starting in 1.22 we have experimental mode parameter, taking options traditional, nolines, packed, packed-overlay, and packed-hover. Traditional is the original gallery type used by MediaWiki. Nolines is like traditional, but with less borders. packed causes images to have the same height, but different widths, with little space between the images. "packed-overlay" allows the caption to be overlaid on top of the image. Last of all "packed-hover" is like "packed-overlay", but with the caption only showing up on hover.

For example:

<gallery mode="packed-hover">
Image:Astronotus_ocellatus.jpg|''[[commons:Astronotus ocellatus|Astronotus ocellatus]]'' (Oscar)
Image:Salmonlarvakils.jpg|''[[commons:Salmo salar|Salmo salar]]'' (Salmon Larva)
Image:Georgia Aquarium - Giant Grouper.jpg|''[[commons:Epinephelus lanceolatus|Epinephelus lanceolatus]]'' (Giant grouper)
Image:Pterois volitans Manado-e.jpg|''[[commons:Pterois volitans|Pterois volitans]]'' (Red Lionfish)
Image:Macropodus opercularis - front (aka).jpg|''[[commons:Macropodus opercularis|Macropodus opercularis]]'' (Paradise fish)
Image:Canthigaster valentini 1.jpg|''[[commons:Canthigaster valentini|Canthigaster valentini]]'' (Valentinni's sharpnose puffer)
Image:Flughahn.jpg|[[Image:POTY ribbon 2007.svg|25px]] ''[[commons:Dactylopterus volitans|Dactylopterus volitans]]'' (Flying gurnard)
Image:Fishmarket 01.jpg|''[[commons:Semicossyphus pulcher|Semicossyphus pulcher]]'' (California Sheephead)
Image:Pseudorasbora parva(edited version).jpg|''[[commons:Category:Pseudorasbora parva|Pseudorasbora parva]]'' (Topmouth gudgeon)
Image:MC Rotfeuerfisch.jpg|''[[commons:Category:Pterois antennata|Pterois antennata]]'' (Antennata Lionfish)
Image:Cleaning station konan.jpg|''[[commons:Novaculichthys taeniourus|Novaculichthys taeniourus]]''
Image:Synchiropus splendidus 2 Luc Viatour.jpg|''[[commons:Synchiropus splendidus|Synchiropus splendidus]]'' (Mandarin fish)
File:Psetta maxima Luc Viatour.jpg|''[[commons:Psetta maxima|Psetta maxima]]'' (Turbot)
File:Australian blenny.jpg|''[[commons:Category:Ecsenius|Ecsenius axelrodi]]''
</gallery>

Gives (mode: packed-hover):

Optional gallery attributes

The gallery tag itself takes several additional parameters, specified as attribute name-value pairs:

<gallery {parameters}>
{images}
</gallery>
  • caption="{caption}": (caption text between double quotes for more than a word) sets a caption centered atop the gallery.
  • widths={width}px: sets the widths of the images, default 120px. Note the plural, widths
  • heights={heights}px: sets the (max) heights of the images.
  • perrow={integer}: sets the number of images per row. 0 means automatically adjust based on width of screen
  • showfilename={anything}: Show the filenames of the images in the individual captions for each image (1.17+)
  • mode={traditional|nolines|packed|packed-hover|packed-overlay}: See section above (1.22+)
The widths and heights parameters are taken more as suggestions then strict values for packed (and related) modes. Packed modes will adjust the width of images in order to make each row the same length.

Example:

Coding:

<gallery widths=60px heights=60px perrow=7 caption="sunflowers are groovy">
File:Example.jpg
File:Example.jpg
File:Example.jpg
File:Example.jpg
File:Example.jpg
File:Example.jpg
File:Example.jpg
File:Example.jpg
File:Example.jpg
File:Example.jpg
</gallery>

Result:

Link behavior

By default an image links to its file description page. The "link=" option modifies this behavior to link to another page or website, or to turn off the image's linking behavior. Alternatively, you can create a text link to an image's description page or to the image itself.

Text link to image's file description page

Use a colon (:) before File: to link to image's file description page:

[[:File:MediaWiki:Image sample]]

[[:File:MediaWiki:Image sample]]

[[:File:MediaWiki:Image sample|Sunflowers]]

[[:File:MediaWiki:Image sample|Sunflowers]]

Text link to actual image

Use pseudo-namespace “Media” for a text link to the actual image:

[[Media:MediaWiki:Image sample]]

[[Media:MediaWiki:Image sample]]

[[Media:MediaWiki:Image sample|Sunflowers]]

[[Media:MediaWiki:Image sample|Sunflowers]]

(If above gets you instead a text link to the image's file description, not a link to the actual image, perhaps your wiki's namespaces are configured out of compliance with this feature?)


Display image, link it to another page or website

Use "link=" option to link image to another page or website:

Clicking on the below image will take you to MediaWiki:

[[File:Wiki.png|50px|link=MediaWiki]]

50px

Clicking on the below image will take you to example.com:

[[File:Wiki.png|50px|link=http://example.com]]

50px

Display image, turn off link

Use "link=" option with no value assigned to turn link off entirely; the below image is not a link:

[[File:Wiki.png|50px|link=]]

50px

Requisites

Before using images in your page, the system administrator of your wiki must have enabled file uploads and a user has to upload the file. System administrators may also set the wiki to accept files from foreign repositories, such as the Wikimedia Commons. For server side image resizing it is necessary to have a scaler configured (such as GD2, ImageMagick, etc.).

Files at other websites

You can link to an external file available online using the same syntax used for linking to an external web page. With these syntaxes, the image will not be rendered, but only the text of the link to this image will be displayed.

[http://url.for/some/image.png]

Or with a different displayed text:

[http://url.for/some/image.png link text here]

Additional MediaWiki markup or HTML/CSS formatting (for inline elements) is permitted in this displayed text (with the exception of embedded links that would break the surrounding link):

[http://www.example.com/some/image.png Example '''<del>rich</del>''' ''<ins>link text</ins>'' here.]

which renders as: Example rich link text here.

If it is enabled on your wiki (see Manual:$wgAllowExternalImages), you can also embed external images. To do that, simply insert the image's url:

http://url.for/some/image.png

Currently, embedded images cannot be resized, but they may be formatted by surrounding MediaWiki markup or HTML/CSS code.

If this wiki option is not enabled, the image will not be embedded but rendered as a textual link to the external site, just like above.

Displaying a web site screenshot thumbnail

For displaying a web site screenshot thumbnail with MediaWiki, you have to write the full external link image (ending with ".jpg") provided by www.robothumb.com.

You have to set true in your LocalSettings Manual:$wgAllowExternalImages too.

The syntax is simple :

http://www.robothumb.com/src/[url]@[size](.jpg)

where [url] is the url of the page to be displayed, example : http://www.example.com

available sizes for the parameter [size] are :

  • 100x75
  • 120x90
  • 160x120
  • 180x135
  • 240x180
  • 320x240
  • 560x420
  • 640x480
  • 800x600

Example :

http://www.robothumb.com/src/http://example.com@160x120.jpg

Including an external link :

[http://example.com http://www.robothumb.com/src/http://example.com@160x120.jpg]

Note the mandatory space after the first http://example.com.

You can see examples here.

Language: English