Scale bias, Input sizing, Vertical shift – Lumagen Radiance 2021/2041 User Manual
Page 24: Non-linear stretch
Section 5 – Video Configuration
Radiance 2021 and Radiance 2041
rev 082813
18
Scale Bias
Scaling is normally on in order to adjust the source to exactly fit the output resolution. If the bias is set to “On”,
scaling is enabled unless the input and output resolution match exactly. If the scale bias is set to “Off” scaling is
disabled if the input and output resolutions are close. Scaling is disabled/enabled independently for horizontal and
vertical. When the bias is off there can be small borders on the edges of the image. If these areas have bad video
the output
Mask command can be used to blank that portion of the image. The second page of on-screen status
information indicates whether scaling is active (Press OK on the remote twice when no Menu is displayed).
MENU → Input → Video Setup → [Resolution] → Size → [Aspect ratio] → Scale Bias → OK
Input Sizing
Input sizing can be used to compensate for active image size differences between sources. Note: The input size
command does not affect the output size or position. Rather, it affects which input pixels are captured for
processing.
Use the Crop TopLeft command to select the top-left-most active input pixel. Use the Crop BotRight command
to select the bottom-right-most active pixel. For standard-definition sources you should set these controls so that
overscan is about 1.5% on all four sides. For digital high-definition sources, overscan may not be required. Cable
and Satellite Boxes may require more overscan due to size differences between channels. Select the scanline using
the and arrows, and the pixel using the and arrows. The command is:
MENU → Input → Video Setup → [Resolution] → Size → [Aspect ratio] → (Crop TopLeft, Crop
BotRight)
Vertical Shift
The vertical shift is an easy way to move the image up and down without changing the
Input Sizing settings. There
are 15 vertical settings that are shared between all input memories. Select the vertical shift setting and then the
shift value. The command is:
MENU → Input → Video Setup → [Resolution] → Size → [Aspect ratio] → Vert Shift → OK
Non-linear Stretch
Non-linear-stretch (NLS) is used to horizontally stretch a 4:3 aspect ratio source to fit a 16:9 aspect-ratio display or
to stretch a 16:9/1.85 source to fit a 2.35 aspect-ratio display. The image is stretched by a constant amount in the
center section, and by an increasing amount approaching the left and right edges. This eliminates the black
sidebars normally seen when viewing smaller aspect material on a higher aspect display. To use non-linear stretch
press the “4:3”, “16:9” or “1.85” button and then press the “NLS” button.
The goal is to stretch the image to fill the screen in a way that looks as natural as possible. The Lumagen NLS
command is very flexible and allows the image to be adjusted to user preferences to achieve this goal. The NLS
adjustments are center width, center stretch, top cropping and bottom cropping. The center section of the image
is stretched by a constant ratio from 100% to 124%. The width of the center section can be set from 15% to 70%
of the display width. By programming the center section width and stretch amount, the amount of non-linear
stretch in the left and right sections can be optimized. In addition, the top and bottom cropping can be set from 0
to 12%. Increasing the amount of cropping reduces the amount of stretch near the left and right edges of the
image. When setting the cropping parameters, it is recommended that the satellite/cable box menu be checked to
assure that critical parameters remain visible.
Some 4:3 sources fill the entire source image (e.g. DVD 16:9 movies), but other sources place a 4:3 image in the
center of a 16:9 image (e.g. HDTV with up-scaled SD source). This latter case is seen as a “pillar-boxed” image
with black bars on the left and right. The “PILLARBOXED” parameter must be enabled for this case. The Lumagen
will then crop the pillbox bars and stretch the active 4:3 image.
For a 16:9 display, when 4:3 NLS is enabled, the image will fill the screen with a 4:3 (1.33) source for any output
aspect ratio up to 1.85. If the output aspect ratio is greater than 1.85, software limits the maximum width to the
equivalent of 1.78 and adds left and right sidebars.
For a 2.35 display, when 16:9 NLS is enabled, the image will fill the screen with a 16:9 or 1.85 source for any
output aspect ratio up to 2.40. If the output aspect ratio is greater than 2.40, software limits the maximum width
to the equivalent of 2.40 and adds left and right sidebars.
Select the parameter to adjust using the and arrows, and change the value of the selected parameter using
the and arrows. The command is:
MENU → Input → Video Setup → [Resolution] → Size → [Aspect] → NLStretch → OK