White Paper

Technology for improving visibility“Visibility Optimizer” and Its Effect

CONTENTS

1. Introduction ................................................................................................................................................. 2
2. “Visibility Optimizer” ................................................................................................................................. 32-1. LOW-LIGHT CORRECTION ................................................................................................................... 42-2. DEFOG ................................................................................................................................................... 52-3. OUTLINE ENHANCER ............................................................................................................................ 72-4. NOISE REDUCTION................................................................................................................................ 9
3. Summary .................................................................................................................................................... 10

No.15-002 Revision A
December 2015
Product & Business Development Dept.
Product Technology Section

White Paper (Q15B014-AS-09003A)

1/10

1. Introduction
We are engaged in the independent development of visibility improving technologies, including“Smart Insight,” a technology for improving visibility of dark areas.
However, there are scenarios in video surveillance where high visibility is required. Specifically,
these include easy-to-see display for checking surveillance video of dark scenes in nighttime
monitoring or scenes where visibility is lowered by fog, smoke, snow, etc.
In this document, we provide an explanation of “Visibility Optimizer”. This function makes it
possible to create the video that you would see if visual disturbances were not present by removing
undesired information such as fog and smoke. The distinguishing characteristic of this function isthat it can provide display in the optimal form for the viewer by extracting the essential informationfrom the video source and making corrections based on the characteristics of the monitor. Moreover,
the original video is untouched, with all corrections being made within the monitor.

▲DuraVision FDF2306W monitor with Visibility Optimizer

White Paper (Q15B014-AS-09003A)

2/10

2. “Visibility Optimizer”“Visibility Optimizer” optimizes the visibility of video displayed on the monitor by performing four
corrections: “Low-light Correction,” “Defog,” “Outline Enhancer” and “Noise Reduction.” Allcorrections can be turned on and off using the “Visibility Optimization” option on the Visibility
Optimizer Menu or the Visibility Optimizer ON/OFF button on the remote control. Below is anoverview of each correction function and an explanation of their application.

▲Visibility Optimizer Components

Visibility Optimizer Menu
Visibility Optimizer ON/OFF

Auto Fog Detection ON/OFF▲Visibility Optimizer Direct Key

White Paper (Q15B014-AS-09003A)▲Visibility Optimizer Menu Screen

3/10

2-1. Low-light Correction
 Function Overview
The low-light correction function extracts the video’s local contrast information by pixel andadjusts the brightness while preserving the information to correct the brightness while maintaining
the original feel. Additionally, it detects the overall brightness of the video, tone bias and othercharacteristics within the frames and then adjusts the parameters in response to the scenes
dynamically. Specifically, the amount of correction is adjusted, with more on dark scenes and lesson bright scenes, so it is possible to view videos with the optimal amount of correction for various
moving images.
 Application
By enabling this function when surveillance video is dark and hard to see, you can watch a brighter
video. It is particularly effective for improving visibility of nighttime scenes where the whole
screen is dark and scenes that are darkened by shadows.

(No correction)(Correction/Level 1)(Correction/Level 3)(Correction/Level 5) Setting/Control
By using the “Low-light Correction” option on the Visibility Optimizer Menu, you can adjust
brightness at five different levels. The higher the level, the brighter the video will be. You can set itto the optimal brightness for visibility according to the video displayed and the monitor viewingenvironment.

White Paper (Q15B014-AS-09003A)

4/10

2-2. Defog Function Overview
The defog function corrects contrast and color saturation lost due to fog by analyzing the fog
components included in the video by pixel and on the whole screen and removing them.
 Application
By enabling this function for scenes of surveillance video where the screen is whitish due to fog,
smoke, snow, etc. and visibility is diminished, you can watch a video of higher visibility. It isparticularly effective for scenes where fog or snow covers the whole screen.

(No correction)(Correction/Level 1)(Correction/Level 2)(Correction/Level 3)

On the other hand, if there is fog or snow on only one part of the video, the degree of defogging issuppressed. This is because the auto fog detection function estimates the fog concentration on thewhole screen, and if there are parts where there is no fog, it determines that the fog concentration on
the whole screen is low.
Additionally, when displaying the video using the surveillance viewer, the degree of defogging may
be suppressed. This is because the fog concentration is estimated without background information
as the viewer background is a solid color, but if there are stripes or other patterns in the background,the background affects the fog concentration estimate, and it is determined to be low as a result.
If you wish to perform defogging in such cases, you can disable auto fog detection to adjust thedefog function. However, when auto fog detection is disabled, it will perform defogging on video
that does not contain fog and on the viewer part, so there may be adverse effects such as changes incolor density or over accentuation of the edges of the video.

White Paper (Q15B014-AS-09003A)

5/10

▼Partial fog(No correction)(Correction/Auto fogdetection on)(Correction/Auto fog
detection off)

▼Display using viewer(No correction)(Correction/Auto fog
detection on)(Correction/Auto fogdetection on)* Defog determines that the viewer part has a low fog concentration and that the video part has ahigh fog concentration, and as a result, it determines that there is a partial fog on the monitor.
 Setting/Control
By using the “Defog” option on the Visibility Optimizer Menu, you can adjust defogging with threelevels. The recommended level is 3. If the edge, brightness and color saturation correction seems
too intense at a correction level of 3, you can lower it to the desired level.
Additionally, you can configure whether or not to estimate fog concentration on the whole screen
by using the “Auto Fog Detection” option or using the Auto Fog Detection button on the remotecontrol.
White Paper (Q15B014-AS-09003A)

6/10

2-3. Outline Enhancer
 Function Overview
The outline enhancer function does not simply emphasize edges but analyzes the input video andestimates the noise components and amount of blur to correct blur properly and sharpen the video.
Additionally, this function includes skin tone and text detection.
The skin tone detection function makes it possible to preserve natural skin appearance close to theoriginal by detecting skin, which the outline enhancer tends to make appear unnatural, and reducing
the correction.

(Original image)(Detection of skin area)(Without skin tone
detection:
Overemphasis of wrinkles
Lip discoloration)(With skin tonedetection:
Natural appearingenhancement)

The text detection function detects text within the display screen and makes it possible to suppress
the coloring of text and bleeding around it. If enhancement of text in the Viewer makes it hard tosee, the enhancement can be suppressed by enabling the text detection function.

(Original image)White Paper (Q15B014-AS-09003A)(With text detection:
No pseudo contours)(Without text detection:
Pseudo contours generated)

7/10

 Application
By enabling this function for video surveillance when the images are blurry due to digital zoom or
low camera resolution, you can watch a high-visibility video with detailed clarity.

(No correction)(Correction/Level 1)(Correction/Level 3)(Correction/Level 5) Setting/Control
By using “Outline Enhancer” on the Visibility Optimizer Menu, you can adjust the degree ofsharpness with five levels and can adjust it to the optimal setting according to the image
magnification and blurriness.
Additionally, using the “Skin Tone Detection” and “Text Detection” options, you can make skinareas or periphery of text sharper.

White Paper (Q15B014-AS-09003A)

8/10

2-4. Noise Reduction
 Function Overview
The noise reduction function reduces noise without making the video too blurry by analyzing thenoise contained in the video and performing correction according to the noise characteristics. It isalso possible to reduce noise by correcting grid-like noise called “block noise” generated during
video compression.
 Application
Video from surveillance cameras is generally compressed during transmission, and noise is mixed
in during compression. By enabling this function when noise reduces visibility making it difficult tomonitor, you can reduce the noise.
Additionally, noise generated during compression and dark area noise generated during filming may
be exaggerated by low-light correction, defog or outline enhancer. Enabling this function canreduce noise in those cases as well.

(Without correction)(With correction)

White Paper (Q15B014-AS-09003A)

9/10

 Setting/Control
By using “Noise Reduction” on the Visibility Optimizer Menu, you can turn this function on andoff.

3. Summary“Visibility Optimizer” makes it possible to improve poor visibility resulting from fog, smoke andother visual disturbances which was not possible with the previous “Smart Insight” technology for
improving visibility of dark areas.
Each “Visibility Optimizer” function (low-light correction, defog, outline enhancer and noisereduction) facilitate the viewing of nighttime scenes and foggy scenes from outdoor surveillance,
making it easier to check video footage. It also fixes noise generated during video compression andblur resulting from zooming. Moreover, the delay resulting from all of the processes of eachfunction is very small at only a few lines, so it can also be used in real time surveillance.
As a “Visual Technology Company,” we will continue to promote development of image
processing technology that draws out the essential information from video sources to achieve
further improvement of visibility with “Visibility Optimizer” and offer optimal video display
systems to meet our customers’ demands.

All product names are trademarks or registered trademarks of their respective companies. Copyright 2015 EIZO CORPORATION.
All rights reserved.

White Paper (Q15B014-AS-09003A)

10/10