Glossary A–ZLetter V
Video codec
A video codec is the method by which a video is compressed for storage and decoded again for playback.
The word combines “coder” and “decoder”.
Well-known codecs are H.264, also called AVC, its successor H.265 or HEVC, and VP9 and AV1. The codec is not the same as the file format: an MP4 file is a container that can hold video encoded with different codecs. For screen networks, H.264 in an MP4 file is the most widespread and reliable choice, because almost every player can play it. Newer codecs achieve smaller files at the same quality but are not supported by all hardware.
Whether a video plays smoothly depends on whether the player can decode the codec in its graphics hardware. Without that support, the picture stays black, stutters or puts heavy load on the processor. Operators should therefore know which codecs each device type supports and request videos from agencies in an agreed codec. Professional editing formats are not suitable for playback on screens and should be converted beforehand.