Sign in or 
Amplitude vibraimage |
Version 9 - view current page
Amplitude vibraimage (AV) characterized the amplitude of object vibration. It does not mean that AV measures the object displacement (mm), correctly it measures the amplitude of signal changing (V or bit) in every image pixel for frame difference accumulation period. AV calculates by the following formula:
where:
A x,y - is the resulting signal of the x,y-th element of the amplitude vibraImage calculated in time period for N frames;
U x,y,i - the real signal of x,y element in the frame with number i;
U x,y (i+1) - the real signal of x,y element in the frame with number i+1;
N - the number of frames being processed in the frame sequence;
D - the threshold value, typically equal to the image noise level.
AV depends on several factors, such as object movement, accumulation period (N), object illumination, object optical contrast, etc. Vibraimage software displays AV by the standard 256 gradation scale, one color for the one bit of AV.
where:
A x,y - is the resulting signal of the x,y-th element of the amplitude vibraImage calculated in time period for N frames;
U x,y,i - the real signal of x,y element in the frame with number i;
U x,y (i+1) - the real signal of x,y element in the frame with number i+1;
N - the number of frames being processed in the frame sequence;
D - the threshold value, typically equal to the image noise level.
AV depends on several factors, such as object movement, accumulation period (N), object illumination, object optical contrast, etc. Vibraimage software displays AV by the standard 256 gradation scale, one color for the one bit of AV.
