Scaling Frames - Data Translation DT3120 User Manual

Chapter 2

Scaling Frames

18
• Interlaced frames, starting on the next field (odd or even),
• Even fields only, starting with the next even field,
• An odd field only, starting with the next odd field, or
• Odd or even fields only, starting with the next field of either kind.
For example, if the next field is odd, only the odd fields are
acquired. If the next field is even, only the even fields are
acquired.
DT3120 board can perform simultaneous, interpolated, arbitrary
scaling in real-time. This feature is useful if you want to reduce the
size of an image.
The number of lines per frame in the scaled image can range from 1 to
480 for 60 Hz image formats or from 1 to 576 for 50 Hz image formats
(in increments of 1). The number of pixels per line in the scaled image
can range from 4 to 640 for 60 Hz image formats or from 4 to 768 for
50 Hz image formats (in increments of 4).
Using software, you provide the scale factor for the horizontal and
vertical directions. The scale factor is the ratio of the target values (the
total number of pixels or lines in the resulting scaled image) to the
source values (the total number of pixels or lines in the image to
scale) in each direction.
The minimum scale factor is 1; the maximum scale factor is 100
(nominal is 100).