ViewCast Osprey-300, Руководство пользователя

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Chapter 5: Analog Video Driver Properties
Default Size
The standard DirectShow Pin Properties dialog
allows you to select the height and width of
captured video from a dropdown list. The
dropdown list has a particular range of choices
that may or may not fit your needs. The
dropdown list includes one default size that is
provided by the capture driver. The Default Size
control allows you to set up what default size will
be shown.
If you check the Auto Size checkbox, your default
video size will be automatically sized to your crop
settings. The three radio buttons, 1X Crop, 1/2X
Crop, and 1/4X Crop, determine whether the
output size is scaled down from the crop size.
Example 1: If you are running standard
720x480 NTSC video, and the Enable
Cropping checkbox is not checked,
your crop size is 720x480. With Auto
Size checked, and the 1X Crop radio
button selected, your default size will be
720x480; with 1/2X Crop, 360x240; and
with 1/4X Crop, 180x120.
Example 2: If you have enabled cropping
with size 360x240 (one quarter of the full
video area), the default Auto Sizes are as
follows: 1X, 360x240; 1/2X, 180x120;
1/4X, 90x60.
If you leave Auto Size unchecked the default size
radio buttons are disabled and the height and
width edit boxes are enabled. You can set any
default size with the following three restrictions:
• Since the driver does not upscale video,
the default size must be smaller than
the crop size. For example, if the crop
size is 360x240, you cannot set default
size 450x300. If you try to specify an
output size that would result in upscaling
the video, a warning message appears
when you try to exit the Size and Crop
page telling you to correct the size before
proceeding further.