LEDadvertising screen phenomenon of water ripple
In
daily life, when we see beautiful pictures on TV, often pick up the phone to
record down, and at this point, the photo flash tend to appear on the water
ripples and scan lines. In can also bring gorgeous pictures of LED advertising
screen before the photos, also can appear ripples and scan lines, there are
some customers doubt about the quality of the LED advertising screen. Below small
make up detailed analysis to the customer in the heart of doubt, the picture of
water ripple and scan lines are not LED advertising screen caused by quality
problems, but because when you take a photo in mobile phone, camera Angle and
focal length.
First. Concept of water ripple
"Water
ripple" also called "Moore lines," Moore grain is a kind of
expression of the principle of beat. Mathematically speaking, the superposition
of the continuous sine wave frequency close to two synthetic signal amplitude
will change according to the difference between the two frequencies.
Second: appearance of MOORE LINES
Two
slightly different spatial frequency stripe, they left black line position, due
to different interval with, to the right gradually refreshed line can't
overlap.The results of the two overlapping stripes, on the left because of the
black line overlap, so I can see the white line.And right dislocation, white
line on the black line, overlapping the outcome become all black.Have the
change of the white line and all black, comprise the mole.
Third: appearance of led advertising
screen moore lines
If
LED advertising screen pixel distribution density between the camera can
distinguish between the case, then will can decipher the part identification
results, but because of LED advertising screen can't identify the ash terrace
zone, a combination of both will form the regularity of the grain, response is
periodic ripples on the vision.
Forth: how to delete Moore Lines
1,
change the camera position. By around or move up and down, can reduce the
ripple Moore.
2,
change focus. Hd LED advertising screen due to the focus of the image clearly
and height details may cause Moore corrugated production, slightly adjust the
camera focus to change resolution, and thus help eliminate Moore.
3,
change the camera Angle. Moore corrugated, due to camera fixed Angle will be
slightly adjust the Angle of the camera, is a good way to slow Moore lines.
4,
use mirror filter installed directly in front of the camera lens, make its
exposure conditions satisfy the spatial frequency, high spatial frequency part
thoroughly filtered image, opportunities for decreasing the occurrence of
Moore's grain, but it will also be synchronous reduce the sharpness of the
image.
5,
change the lens focal length. Can use different lenses or adjust the focal
length, to change or remove Moore.
If you have interest, you can send me e-mail


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