How to Use the Instrument
Description and Applications of the Test Patterns
4
4-67
Moving Block
Moving Block is a full field B/W pattern with color burst. A vertical white block with
Y = 100% (100 IRE) moves smoothly from left to right on a black background. Duration
of one moving cycle is 4.7 s for 625 line systems and 4.0 s for 525 line systems.
This test pattern can be used to check the correct digital video processing, especially AD
conversion of modern TV equipment. Moving pictures or slow motion function can be
checked on VCRs by the pattern.
Figure 4-100. Moving Block
Progressive Scan Check 1
This B/W pattern with color burst offers four horizontal white lines on a black
background moving in vertical direction from top to bottom. The motion can be switched
off at any position of the screen by selecting the
DIGI_SCAN1_S
test pattern. The pattern
contains 50 Hz and 25 Hz test signals for 625 line systems respectively 60 and 30 Hz
signals for 525 line systems.
The first white line is only present in the first or second field. This will result in a 25 Hz/
30 Hz test signal. The second horizontal line is composed of a line in the first and second
field producing a normal interlaced 50 Hz/ 60 Hz signal. The third and fourth white lines,
comprising two TV lines, are combinations of the first two lines.
A. 1 TV line (one field only)
B. 1 TV line (1. and 2. field)
C. 2 TV lines (1 TV line as A and 1 line as B)
D. 2 TV lines (2 TV lines as B)
Figure 4-101. Progressive Scan Check 1
Applications:
Progressive Scan Check is a special test pattern to test modern Enhanced Definition TV
equipment that is commonly used for bigger picture tubes. In these TVs the 50 Hz/ 60
Hz transmitted images are stored, processed and read out with double picture tube scan
rate. This process doubles the field frequency and avoids typical 50 Hz/ 60 Hz picture
disturbances like image flicker.
For reduction of the line flicker, different video processing techniques, for example
Digital Scan, are used in such TV.
To Next Page
Loading...