LED Processor
Definition
An LED processor is the device that converts an incoming video signal into data for an LED wall. It maps the image onto the physical layout of the cabinets and sends the data, usually over Ethernet cables, to the receiving cards in each cabinet. Each output port has a pixel capacity: Brompton gives 525,000 pixels per 1G port at 8 bits and 60 Hz for its Tessera processors, and NovaStar about 650,000 pixels per Ethernet port for its common sending cards. A larger wall requires more ports, or a lower frame rate or bit depth. Common manufacturers include NovaStar, Brompton (Tessera), Megapixel (Helios, formerly Megapixel VR) and Colorlight.
In the field
Scan lines, banding or flicker that appear on camera but not to the eye come from the interaction between the LED refresh (the PWM cycle of the panels) and the camera shutter. Common remedies are genlocking the processor to the camera reference, choosing a shutter speed or angle that covers whole refresh cycles, and raising the panel refresh rate. Brompton's ShutterSync function aligns the LED refresh period with the shutter period entered by the operator.
Related lessons
Sources
- Brompton Technology, Tessera Output Capacity : 525 000 pixels par port 1G en 8 bits à 60 Hz · bromptontech.com
- NovaStar, MSD600 Sending Card Specifications : capacité de charge par carte et par port Ethernet · oss.novastar.tech
- Brompton Technology, ShutterSync : alignement du rafraîchissement des dalles sur la période d'obturation, avec genlock · bromptontech.com
- Brompton Technology, Recreating Reality: Synchronisation Artefacts : artefacts de synchronisation entre mur LED et caméra · bromptontech.com
- Megapixel, HELIOS : plateforme de traitement LED de Megapixel, présentée sous le nom Megapixel VR sur le site du fabricant · megapixelvr.com