Wikipedia:Image Use Policy - Format

Format

See also: Wikipedia:Preparing images for upload

• Drawings, icons, political maps, flags and other such images are preferably uploaded in SVG format as vector images. Images with large, simple, and continuous blocks of color which are not available as SVG should be in PNG format.
• Software screenshots should be in PNG format.
• Photos and scanned images should be in JPEG format.
• TV and movie screenshots should be in JPEG format.
• Inline animations should be in animated GIF format.
• Video should be in Ogg/Theora format.

In general, if you have a good image that is in the wrong format, convert it to the correct format before uploading. However, if you find a map, flag, etc. in JPEG format, only convert it to PNG if this reduces the file size. For further advice on converting JPEG to PNG, see Wikipedia:How to reduce colors for saving a JPEG as PNG.

Most of the maps on the CIA World Factbook website were coded as JPEG, but are now coded as GIF. To update these photos, download the GIF picture from the CIA factbook, resave it in PNG format, and upload it to Wikipedia.

Try to avoid editing JPEGs too frequently—each edit creates more loss of quality. If you can find an original of a photograph in 16-bit or 24-bit PNG or TIFF, edit that, and save as JPEG before you upload. A limited variety of edits (crops, rotation, flips) can be performed losslessly using jpegcrop (windows) or jpegtran (other); try to use this where possible.

Avoid images that mix photographic and iconic content. Though CSS makes it easy to use a PNG overlay on top of a JPEG image, the Wikipedia software does not allow such a technique. Thus, both parts must be in the same file, and either the quality of one part will suffer, or the file size will be unnecessarily large.

Direct SVG support is implemented as of September 2005 (see meta:SVG image support). The SVG is dynamically rendered as a PNG at a given size when inserted into an article. If you find that a SVG image is being cropped too closely by Wikimedia's rendering software, one way around this is to draw a box around the image at the distance it should be cropped, and set the box to have no fill and no stroke color.