Help:Images

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This page explains the image syntax when editing the wiki. You or another user must usually Special:Upload 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).
  • .tiff : Tagged image format. Often used for high-resolution archival photographs.
  • .ogg, .oga, .ogv : Ogg multimedia (audio or video) Not an image format, but treated similarly.
  • .pdf : multipaged documents in the Portable Document Format (initially specified by Adobe).
  • .djvu : multipaged bitmap documents in the DejaVu format (most often, scans of books).
    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) — Displays an image without any activable link; e.g. [[File:Example.jpg|20px|link=]] renders as Example.jpg.
      • ! Link does not work with thumb, thumbnail or frame.
      • ! If you set |link=| (empty), then no title will be rendered.
  • Other specific options:
    • alt={alternative text} — Defines the alternative text (maps to the HTML attribute alt="..." of the generated <image /> 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).

The options can be given in any order. If the given options conflict each other, the latter is applied, except for the format options, where the options take the priority in the order of: frame; thumb (or thumbnail); frameless and/or border.

If a parameter does not match any of the other possibilities, it is assumed to be the caption text. Caption text shows below the image in thumb and frame formats, or as mouseover text in border, frameless formats or when the format is omitted. 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.

If no caption text is supplied, a caption is automatically created showing the file name. To completely remove the caption, set it to <span title=""></span>. For example, [[File:Example.jpg|20px|<span title=""></span>]] renders as .

Format

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.

Horizontal alignment

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

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.


Rendering a gallery of images

Gallery syntax

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

<gallery>
Image:file_name.ext|caption
Image:file_name.ext|caption
{...}
</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.

for example:

<gallery>
File:Example.jpg|Item 1
File:Example.jpg|a link to [[Help:Contents]]
File:Example.jpg
File:Example.jpg
File:Example.jpg| ''italic caption''
File:Example.jpg|on page "{{PAGENAME}}"
</gallery>

is formatted as:

Optional gallery attributes

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

<gallery {parameters}>
{images}
</gallery>
  • caption="{caption}": (caption in parentheses 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.
  • showfilename={anything}: Show the filenames of the images in the individual captions for each image (1.17+)

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:

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.