DirecTV HD DVR User Manual page 165

- Stretch
In the Stretch setting, instead of adding bars to the top and bottom, the 16:9 program image is stretched vertically until it's tall enough
to fill the screen. Your entire screen will be full, but the program images are stretched to compensate.
- Crop
This format crops (cuts off) the left and right portions of the 16:9 frame so it fits the 4:3 screen.
If your display is a 4:3 format TV or monitor, your format options include these:
For 4:3 program signals:
For 16:9 program signals:
Fills TV Screen
Letterbox
Appendix 3: About High-Definition
Stretch Crop
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