Image format (JPEG, PNG)

The most common formats are JPEG for photographs and PNG for graphics with sharp edges, text or transparency.

JPEG makes files much smaller by discarding image information the eye hardly notices. This suits photographs but creates visible blurring around sharp edges and text. PNG stores images losslessly and can carry an alpha channel, but its files are larger. There are also WebP, which supports both kinds of compression, and SVG for vector graphics, which not every player can display. For a Full HD screen, an image of 1920 × 1080 pixels is enough; larger files burden storage and transfer without any visible gain.

Common mistakes come from print production: images in the CMYK colour model, which is intended for printing, are often displayed incorrectly or not at all on screens. Images for screens belong in RGB, most safely in the sRGB colour space. Embedded bleed and crop marks from print files have no place on a screen either.