FAQ: What is EDID in the context of video displays?

EDID is a protocol that enables digital video display technologies like HDMI, DVI and DisplayPort.

According to Wikipedia
“Extended display identification data (EDID) is a data structure provided by a digital display to describe its capabilities to a video source (e.g. graphics card or set-top box). It is what enables a modern personal computer to know what kinds of monitors are connected to it. EDID is defined by a standard published by the Video Electronics Standards Association (VESA). The EDID includes manufacturer name and serial number, product type, phosphor or filter type, timings supported by the display, display size, luminance data and (for digital displays only) pixel mapping data.”

What is EDID’s role?

EDID enables the flow of digital AV content from the digital source to a digital display. It is a critical element to establishing two-way communication in HDMI, DVI, and DisplayPort.
The first step towards facilitating two-way communication is the EDID exchange, and this is followed by HDCP authentication if the content is HDCP-encrypted. Both these stages of authentication failure must be completed if digital AV content is to flow from source to display.

What problems can EDID related issues cause?

According to Extron…

“HDMI, DVI, and DisplayPort require successful two-way EDID exchange between a display and a source to establish
a connection between them. Problems with EDID communication are major causes of failure in digital video systems, with no image display as the typical symptom.”
“…EDID also has a long history in AV and is widely familiar to integrators. However, it is also difficult to fully understand, and perhaps more importantly, to effectively troubleshoot when things go wrong in a digital video setup.”

AV Solutions, Audio Visual Consultants at Actis Technologies India