SDA9410
5.9
Preliminary Data Sheet
Motion compensation
Motion compensation
In the SDA 9410 the motion estimation algorithm is combined with an advanced scan
rate conversion algorithm. The Figure 45 shows the position of the fields as a function
of the time for a 50 Hz sequence and a 100 Hz sequence. The information of the motion
estimation (vector field) can be used for the generation of the additional fields. The A field
is directly used as "a" field. The B field has the right position, but the wrong phase. The
line-scanning pattern interpolation into a A field can be used as "c" field. The "b" and "d"
field has to be generated using the vector field of the motion estimation.
100 Hz sequence
50 Hz sequence
An
an
bn
cn
dn
Bn
an+1
An+1
time
Figure 45
Timing of 100 Hz scan rate conversion
The Figure 46 shows a moving object as a function of the time. The position of the object
in the b field is exactly half the position of the object in the A and B field. That‘s why no
double contours are visible.
An
Bn
cn
50 Hz sequence
an
bn
100 Hz sequence
time
Figure 46
Principles of motion compensation
The principle of the up conversion process is illustrated in the Figure 47 in case of the b
field. Motion compensated pixels are fed to a 5-tap median filter. The background is that
in case of correct motion vector, it can be expected that the two motion compensated
pixels from both neighboring fields are identical. Consequently, either of the two is
selected and a correctly motion compensated intermediate field results. In the figure
below the vector ends on a non existing line. Therefore the pixels of the line before and
after the non existing line are taken. Is the vector unreliable for the current pixel, the two
100
Micronas
MICRONAS [ MICRONAS ]
