Wikipedia:Manual of Style/Images: Difference between revisions

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This page documents an English Wikipedia content guideline.

Editors should generally follow it, though exceptions may apply. Substantive edits to this page should reflect consensus. When in doubt, discuss first on this guideline's talk page.

Shortcuts

Example caption
*To produce this box, use:*
`[[File:Example.png|thumb |alt=Example alt text |Example caption]]`

Wikipedia contains millions of illustrative images and other electronic media. This page gives a very brief overview of how images are used in Wikipedia; for more information, see Image use policy, and see Help:Files on how to upload and include an image.

Image preferences

Logged in users can set their default viewing size of thumbnails in the "my preferences" area under "appearance", which offers an opportunity to customize "files". The default size for users that are not logged in is 220 pixels. Logged in users can choose from widths of 120px, 150px, 180px, 200px, 220px, 250px or 300px.

Also under "files" in the "my preferences" area, one can set the size limit of images shown on image description pages. By default, if either the width or the height exceeds 800px or 600px respectively, then the image is reduced in size until it fits within those dimensions. This can be changed to the default size of 320×240px, 640×480px, 800×600px, 1024×768px, 1280×1024px or 10000×10000px, if preferred. The last choice will effectively display all images at 100% resolution.

Using images

Images uploaded to Wikipedia are automatically placed into the file namespace, formerly known as the image namespace. This means that names of image pages start with the prefix "File:". To incorporate an image into an article, you will need to use image syntax. As an example in a simple form, in order to reproduce the image at the top of this page, insert the following text into an article:

[[File:Example.png|thumb|alt=Example alt text|Example caption]]

The first parameter is the full name of the image, (i.e., File:Example.png). You must reproduce the exact name of the image file including its capitalization, spacing and not omit its file extension such as .jpg.
The second "thumb" parameter forces the creation of a thumbnail.
The third parameter, "alt=Example alt text", can be modified to specify suitable alt text.
The last parameter, "Example caption", can be replaced with any suitable caption.

Alt text is meant for readers who cannot see the image. It summarizes the image's appearance, not its meaning, and typically has little in common with the caption. Alt text also helps search engines find Wikipedia articles.

The full set of options is more complex; however, the vast majority of images should be able to be displayed by using the above format.

If the image does not show up and you are sure the syntax is correct, it may have been blacklisted. See MediaWiki:Bad image list for a list of such images.

Note: The "File:" prefix may be used interchangeably with "Image:":

[[Image:Example.png|thumb|alt=Example alt text|Example caption]]

Inline linking

"WP:HOTLINK" redirects here. For guidelines on hotlinking images on Wikimedia servers, see commons:Commons:Reusing content outside Wikimedia#Hotlinking.

Shortcut

WP:HOTLINK

Inline linking of images on external sites for display on Wikipedia is disabled for several reasons:

inline linking to images on other sites is often considered "leeching"; content sites where the image is stored and from which it is retrieved may not like the new placement
allowing inline image linking makes it easier for vandals to post images from shock sites
allowing inline image linking makes it easier to introduce copyrighted images without obtaining an acceptable free license
inline linking to an image stored on another site increases the bandwidth use of that site, even though the site is not being viewed as intended

Instead, to place an image on Wikipedia, you will need to upload it.

Forced image size

As a rule, images should not be set to a larger fixed size than the 220px default. If an exception to the general rule is warranted, forcing an image size to be either larger or smaller than the 220px default is done by placing a parameter in the image coding in the form |XXXpx, where XXX is replaced by a number of pixels, for example:

[[File:Example.png|thumb|120px|alt=Example alt text|Example caption]]

Forced left justification

In most cases, images should be right justified on pages, which is the default placement. If an exception to the general rule is warranted, forcing an image to justify on the left side of a page is done by placing a parameter in the image coding in the form |left, for example:

[[File:Example.png|thumb|left|alt=Example alt text|Example caption]]

Obtaining images

All images on Wikipedia must comply with the image use policy. This means that they must be free for commercial use and alteration. However, some fair use of non-free content is allowed in limited circumstances.

Making images yourself

You may take a photograph with your digital camera, scanner, or integrated mobile phone, draw an image or graph digitally, perhaps with a graphics tablet, or scan drawings and photos taken with a camera and then upload the image.

Try to avoid including text in images or diagrams; you can use Template:Annotated image to add text (and links) that users can interact with.

Finding images on the Internet

An extensive list of free image resources by topic can be found at: Public domain image resources. In addition to Wikimedia Commons, the Wikimedia Toolserver has a Free Image Search Tool (FIST), which automatically culls free images from the Wikimedia sister projects, Flickr and a few other sites. Several other useful, general purpose image search engines include: Google Image Search, Picsearch and Pixsta. Creative Commons licensed images with Attribution and Attribution-ShareAlike as their license may be used on Wikipedia. Images with any license restricting commercial use or the creation of derivative works may not be used on Wikipedia.

If you find an image on the Internet that is not available freely, you can email the copyright owner and ask for their permission to release it under a suitable license, adapting the boilerplate request for permission. If you cannot find a suitable image, you may also list your request at Wikipedia:Requested pictures, so that another contributor may find or create a suitable image.

Requesting images from others

See

Wikipedia:Requesting copyright permission
Wikipedia:Donating copyrighted materials
Wikipedia:Declaration of consent for all enquiries
Wikipedia:Requested pictures (for requesting Wikipedians to take photos etc.)

Uploading images

Logged in users with autoconfirmed accounts (meaning at least four days old and at least ten edits) can upload media to Wikipedia. It is recommended that only free licensed media, not fair use media, be uploaded to Wikimedia Commons. Media on Wikimedia Commons can be linked to in the same way as media of the same name on Wikipedia. To upload media to the English Wikipedia, go to special:upload and for Wikimedia Commons, go to commons:special:upload. For preferred file formats see Wikipedia:Preparing images for upload.

Each image has a corresponding description page. On that page, one should document the source, author and copyright status of the image, using one of the pre-defined image copyright tags. It is important to add both descriptive (who, what, when, where, why) and technical (equipment, software, etc.) information at the time of creating the page, which will be useful and highly informative to later editors and readers. Also, WikiProject Sexology and sexuality has a very important guideline on WIP images, that should be reviewed before uploading.

Consideration of image download size

In terms of physical memory on a computer, typical images on Wikipedia can range in size from a few kilobytes to several megabytes. Thus, images can easily form the primary bandwidth component of an article download. If a page is rich with big image files, the download time can be significantly impacted, particularly for a client who has a low bandwidth network connection. Slow downloads can lead to user frustration, so it may be beneficial to look for means to reduce the article's memory footprint.

Wikipedia aids the download performance by converting full images into thumbnails before they are transmitted. However, not all image formats provide a significant size reduction through this technique. In most browsers you can review the memory footprint of downloaded images by moving the cursor over the image, right-clicking, then selecting Properties. The resulting window will show the resulting file size in Kb or Mb. For best results, you may want to focus on reducing the size of the largest image files on a page, particularly when they are disproportionately large compared to other images.

There are several image file formats available, each with their own benefits and drawbacks. One method of reducing the image downloaded time is to change the chosen format.

GIF images with a frame size larger than 12.5 million pixels (measured as pixel height × pixel width × number of frames in the animation) cannot currently be displayed in thumbnail form in Wikipedia articles. A thumbnail of a GIF image can be considerably larger in filesize than the original image. For the best results, try to upload GIF images in the framesize that you intend to use in the article.
Animated GIF images have a few additional restrictions. Images larger than 12.5 million pixels (measured as pixel height × pixel width × number of frames in the animation) currently will only show the first frame of the animation in a thumbnail. When not using a GIF animation at its original frame size, consider creating an Ogg Theora movie of the animation.
The PNG format is useful for storing graphics that contain text, line art, or other images with sharp transitions. It can achieve the same graphical results as a GIF file, and in many cases do so with a higher rate of file compression. For this reason, PNG format files are usually preferred to the GIF format. (However, for certain types of images, PNG thumbnailing is not as efficient as GIF thumbnailing, when Wikimedia GIF thumbnailing is enabled.)
A JPEG or other compressed image format can be much smaller than a comparable GIF or PNG format file. When there is no apparent difference in quality, such as with a photograph that has no sharp graphical transitions, a compressed image format such as JPEG may be preferable for reasons of download performance. Wikipedia is often able to achieve much better compression of JPEG photograph thumbnails than comparable PNG images, and with little perceptible loss of quality.
Where an image consists solely of line art, charts text and simple graphics, an SVG file can be significantly smaller than other graphics formats. This is because the data is encoded as a series of drawing commands, rather than as raster graphics. There are open source applications available for rendering graphics in SVG format. However, SVG thumbnails are rendered as PNGs.
Rather than including an image gallery on an article, which could add significantly to the download size, consider creating a gallery/category on the Wikipedia Commons instead.

Image choice and placement

Beyond the basics of copyright and markup, editors face choices of image selection and placement. Some editors maintain that photographs are preferable to paintings and sketches. Notable exceptions exist. Bird identification guides have traditionally used sketches. Other editors dispute giving any preference to photographs.

Articles that use more than one image should present a variety of material near relevant text. Three uniformed portraits would be redundant for a biography of a famous general. A map of a battle and a picture of its aftermath would provide more information to readers.

Images should be large enough to reveal relevant details without overwhelming the surrounding article text. Similar types of images within an article often look appealing if they appear at the same pixel size. Poor quality images (too dark, blurry, etc.) or where the subject in the image is too small, hidden in clutter, ambiguous or otherwise not obvious, should not be used.

Contributors should be judicious in deciding which images are the most suitable for the subject matter in an article. For example:

An image of a White-tailed Eagle is useless if the bird appears as a speck in the sky.
Gloria Steinem looks best as a portrait photograph of herself alone, not with other individuals.
A suitable picture of a hammerhead shark would show its distinctive hammer-like head, to distinguish it from other species of shark.
A map of Moldova should show its frontiers with Romania and Ukraine, so people may know where the country actually is, in relation to its neighbors.
Rice is best represented with an image of plain rice, not fried rice.
Intangible concepts can be illustrated; for example, a cat with its claws out portrays aggression, while a roadside beggar juxtaposed with a Mercedes-Benz shows social inequality.

Pertinence and encyclopedic nature

Images must be relevant to the article that they appear in and be significantly and directly related to the article's topic.

Images are primarily meant to inform readers by providing visual information. Consequently, images should look like what they are meant to illustrate, even if they are not provably authentic images. For example, a photograph of a trompe-l'œil sculpture of a cupcake may be an acceptable image for Cupcake, but a real cupcake that has been decorated to look like something else entirely is less appropriate. Similarly, an image of an unidentified cell under a light microscope might be useful on multiple articles, so long as there are no visible differences between the cell in the image and the typical appearance of the cell being illustrated.

To maximize the utility and educational value of an image, please describe its contents as fully as possible on the image's description page. For example, photographs of artwork benefit from documentation of the artist, title, location, dates, museum identification numbers, etc. Images that are described only in vague terms (e.g., images with descriptions such as "a cuneiform tablet", "a medieval manuscript", etc.) are often less useful for Wikipedia and less informative to our readers.

Reliable sources, if any, may be listed on the image's description page. Generally, Wikipedia assumes in good faith that image creators are correctly identifying the contents of photographs they have taken. For example, if you take a picture in your neighborhood, you do not need to produce a published, independent reliable source to prove that you took the picture in your neighborhood. However, if such sources are available, please provide them. This is particularly important for technical drawings, as someone may want to verify that the image is accurate.

Offensive images

Including information about offensive material is part of Wikipedia's encyclopedic mission. Wikipedia is not censored. However, images that can be considered offensive should not be included unless they are treated in an encyclopedic manner. Material that would be considered vulgar or obscene by typical Wikipedia readers should be used if and only if its omission would cause the article to be less informative, relevant, or accurate, and no equally suitable alternative is available.

Life cycles of images

Eventually, some of the images reach the end of their life cycle. They may be superseded or replaced by an image with a friendlier copyright policy. If you come across an image that needs to go for copyright reasons, list it on Files for deletion. However, superseded images should be kept to preserve Wikipedia's historical record. The history of articles can be difficult to assess if images and templates have been deleted over the years.

Conversely, if you have contributed or found an image that stands out from the crowd, you are invited to nominate it for inclusion on the Featured pictures list.

@@ Line 132: / Line 132: @@
 ==Life cycles of images==
-Eventually, some of the images reach the end of their life cycle. They may be superseded or replaced by an image with a friendlier copyright policy. If you come across an image that needs to go, list it on [[Wikipedia:Files for deletion|Files for deletion]].
+Eventually, some of the images reach the end of their life cycle. They may be superseded or replaced by an image with a friendlier copyright policy. If you come across an image that needs to go for copyright reasons, list it on [[Wikipedia:Files for deletion|Files for deletion]]. However, superseded images should be kept to preserve Wikipedia's historical record. The history of articles can be difficult to assess if images and templates have been deleted over the years.
 Conversely, if you have contributed or found an image that '''stands out from the crowd''', you are invited to [[Wikipedia:Featured picture candidates|nominate]] it for inclusion on the [[Wikipedia:Featured pictures|Featured pictures]] list.