Extron Electronics VN-QUANTUM User Guide - Manual (Page 62)

Section 3: Functional Overview VN-QUANTUM User Guide
Page 62 I455GB issue 8
De-interlacing
VN-QUANTUM outputs a progressive scan to the target display. Most sources that will be connected
to the Video Input Card will be interlaced scan and need to be converted to a progressive scan (or
‘de-interlaced’. The Video Input Card can use one of two de-interlacing modes:
Single Field Interpolation
Three Field Interpolation
For a full explanation of these modes please see page 76.
Down-Scaling of Video Sources
The on-board scaler provides down-scaling (minification) of video sources. Independent horizontal
and vertical scaling is possible down to 1/16 of native resolution. For example, a source of 720x486
pixels can be scaled down to around 45x31 pixels.
More than one scaled version of each source is possible, subject to the maximum number of sources
supported by the scaler:
Maximum number of
Sources Supported (per card)*
Source Type De-interlacing
Real-time Absolute
Single field 30 64 Video
(PAL/NTSC/SECAM)
Three field 15 64
* Also dependant on the source capacity of the RAPT bus.
The scaling engine is built around Electrosonic’s patented convolver technology. This ensures that
original image detail and quality is maintained at all times.
Up-scaling (magnification) is achieved by a scaler on the Output Card. See page 75 for
further details on source scaling.
Source Transfer
Digitized video sources are transferred on to the RAPT bus for transport to the Output Card(s).
NOTE: VN-GLIMPSE RGB sources use a DMA (Direct Memory Access) process on an ES3311-2
Input Card to transfer source data to the RAPT bus.
Only sources that are currently visible on the target display are transferred to the bus.