Panel Setup - Martin LC 2140 User Manual

Panel setup

This section describes how to set panels to display a video image.
Video image resolution
Because LC 1140 panels can only display 25 x 25 pixels and LC 2140 panels can only display 25 x 50
pixels, to map every pixel in a 1024 x 768 pixel video image to a single pixel in a video curtain would require
a very large installation with 41 panels horizontally and either 31 LC 1140 or 16 LC 2140 panels vertically.
This arrangement would give full 1024 x 768 resolution with a few spare pixels at the edges.
Your installation probably has a smaller number of panels than this, so you can set up the output from your
media server in two ways:
• You can display an area of the video image that has the same number of pixels as your installation at full
pixel resolution (one pixel in the installation displays one pixel of the video image). The advantage of this
is that you do not lose any detail from this area of the image, but the disadvantage is that you can only
display part of the video image.
• You can display an area of the video image that has more pixels than your installation, but at reduced pixel
resolution (one pixel in the installation displays an "average" of more than one pixel in the video image).
The advantage of this is that you can display more of the video image than in the first method, but
because you only have a limited number of pixels in your installation, you must accept loss of detail from
the video image.
If you have a limited number of LC panels, you are thus faced with a trade-off between the amount of the
video image you display and the amount of detail that is possible: the more of the video image you display,
the less detail you can display. To take an extreme example of this, it is possible to display a full 1024 x 768
video image on one LC panel, but you have to accept a very significant reduction in video image resolution
and loss of detail.
To reduce the resolution of a full 1024 x 768 video image, 'shrink' the image on your monitor screen until it
contains the same number of pixels as your installation. For example, to display a full 1024 x 768 video
image on an installation 200 pixels (8 panels) wide and 150 pixels (6 x LC 1140 panels or 3 x LC 2140
panels) high, you must 'shrink' the image to just under 20% of its original size, so that it fits in an area on
your monitor screen 200 pixels wide and 150 pixels high.
Note that LC panels cannot 'shrink' a video image themselves – 'shrinking' must be carried out on the media
server.
If your installation has the same aspect ratio as the video image (e.g. 1024 x 768, 800 x 600, 400 x 300, 200
x 150 pixels etc. for a 4:3 aspect ratio image), you can display the full video image using all the pixels in your
installation. However, the smaller your installation is, the more you must 'shrink' the video image, reducing
its resolution and thus the amount of detail you can display.
Tiles in the video image
The DVI signal on the video link contains the full video
image information everywhere on the link, so each
panel on the link receives the full video image. One
panel can display only a small part of the full image,
however, so each panel divides the video image into
25 x 25 pixel "tiles" as shown in Figure 11, and then
displays one or two tiles:
• an LC 1140 panel displays one tile
• an LC 2140 panel displays two tiles – one tile plus
the tile below it.
Setting panels to display tiles
To identify individual tiles, a panel gives each tile an x
and a y coordinate according to the following
principles:
• Coordinates are numbered starting at the top
left-hand corner of the video image when facing the
video image.
• The top left-hand tile is given the coordinates x = 0, y = 0.
• The next tile to the right is one tile further along the x axis, so it is given the coordinates x = 1, y = 0. After
this tile, the next tile to the right is assigned the coordinates x = 2, y = 0, and so on.
• The tile below the top left-hand tile is one tile further down the y axis, so it is given the coordinates x = 0,
y = 1. The next tile down is assigned the coordinates x = 0, y = 2, and so on.
Figure 11: Tiles in the video image
Video link
25pix
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