Relationship Between Input And Output Image; Cropping - evertz 7710ARC Series Manual

7700 MultiFrame Manual
7710ARC Series - SD Aspect Ratio Converter

6.2.2. Relationship Between Input and Output Image

Both card input and output images follow the model outlined above in section 6.2.1.2. The source frame,
input image, destination frame and output image aspect ratios are totally independent of each other.
When the input image aspect ratio is different from the output image aspect ratio, the input image is
converted to "fit" into the output image aspect ratio using 1 of the 3 following methods:
•

Cropping

•
Stretching
•
Filling
The following descriptions and diagrams will illustrate cropping, stretching and filling based on the
following reference input image:
Solid Line shows
extent of the "Image"
which is the portion of
the frame that is being
utilized for program
content .
6.2.2.1. Cropping
In cropping mode, parts of the input image are removed to make it "fit" into the output image. The aspect
ratio of objects inside the output image area is preserved (i.e. circles remain as circles, squares remain as
squares, etc.).
If the input image aspect ratio is greater than the output image aspect ratio, the entire height of the input
image is used and only a portion of the width is used. When an equal amount of the image is removed on
each side it is commonly referred to as centre crop or side cut mode.
Figure 6-10: Large to small aspect ratio crop - Side Cropping
7710ARC-14
Figure 6-9: Reference Image
Output Image - Crop
Revision 1.1
Dashed Line shows
edge of "Frame"
which could also be
referred to as the
production aperture of
the video.
Circles represent
image content and
show whether the
image has been
distorted, or cropped
during resizing