Instruction
Manual
DataVS1
Series
77
14. TUTORIAL
14.1.
Digital image
Digitisation allows real images acquired by a camera to be treated using a processor.
This is done in two steps:
sampling: image is divided into a dot matrix. Dots are termed picture elements (or more
commonly pixels);
quantisation: each pixel is associated to a numeric value.
Such information may signify point brightness for grey scale images (0 = black, 255 = white), or three
values (Red-Blue-Green, RGB coding) for colour images.
As a result, the real image is converted to a mathematical format (pixel matrix) which can be
processed by a personal computer.
sampling
quantisation
real image
(grey scale)
Detail of sampling
Pixel matrix with brightness
information
The maximum resolution of the DataVS1 sensor is 640 × 480 pixel. This means that the acquired
images will be processed by a personal computer as 640×480 element matrixes (307200 values).
Each element is identified by its location in the matrix, i.e. by specifying column and line and
considering the first element in the top left corner as the origin (in the matrix shown above, this would
be the pixel with brightness equal to 20).
X coordinate axis
Origin
pixel
(0,0)
Y coordinate
axi
s
0 1 2 3 4 ...
0
1
2
3
4
5
6
...
Position pixel
(2,3)
