HDMI – High Definition Multimedia Interface
HDMI is a new standard for the digital transmission of high-resolution audio and video data. The HDMI standard supports encryption of the transmitted data, which is intended to prevent unauthorised copying. If the projector or plasma display has no electronics to decode the data, the image either stays black or is only shown at reduced resolution. Projectors only need image information, which is why projectors with DVI (and HDCP) are compatible with HDMI via an adapter, and vice versa.
The industry itself recognised the information chaos as a problem and, through its association EICTA (European Information & Communications Technology Industry Association), set a minimum standard. At the same time, a quality label called "HD ready" was developed. This gives consumers certainty along the lines of: "Only where it says 'HD ready' is there HDTV inside". We strongly recommend buying only plasma and LCD TVs or projectors that carry this label or whose sellers explicitly confirm the technical specifications behind it.
Technical requirements:
1. The display (e.g. LCD or plasma) or the panel processor (e.g. DLP) must have a native resolution of at least 720 pixels vertically in 16:9 format. In other words, 720 vertical pixels must physically be present.
2. The following video inputs must be present:
● HD video inputs (HD = High Definition)
– Analogue: YUV (YPbPr), also called component video
– Digital: DVI or HDMI (with HDCP copy protection)
● The HD video inputs must be able to process these formats:
– 1280×720 at 50 Hz and 60 Hz progressive ("720p")
– 1920×1080 at 50 Hz and 60 Hz interlaced ("1080i")
● The digital DVI and HDMI inputs must support HDCP copy protection.
HD satellite receivers and compatibility
HD satellite receivers:
EICTA has also introduced a quality label for satellite receivers, which identifies HDTV-capable satellite receivers and screens with integrated HDTV receivers. To qualify, these devices must be able to play MPEG-2 and MPEG-4/H.264 video signals in 720p and 1080i. In addition to a digital audio output – where digital sound output via HDMI must be available alongside Toslink – the device needs a YUV, DVI or HDMI output to be compatible with "HD ready" screens. If a satellite receiver meets these requirements, it is technically ideally prepared for HDTV.
back to projector technology and terms
Matching product categories in the shop:
Further guides:
- Projector buying guide using the BEAM method – overview of all guides
- Audio Return Channel – HDMI ARC for sound explained
- Projector connections – which connection for what
