Raspberry Pi A, Руководство пользователя, Страница: 289 / 314

A P P E N D I X B
R A S P B E R R Y P I C A M E R A M O D U L E Q U I C K R E F E R E N C E
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❍
-ex or --exposure (Exposure Mode)— Sets the camera’s automatic exposure setting,
which controls how long the camera spends capturing an individual image or frame
and is largely a factor of available light or the speed of the subject: fast-moving objects
need a short exposure time in order to remain in focus, while low-light shooting
demands a long exposure time. Possible values for this option are
off
, au
t
o,
night
,
nightpreview
,
backlight
,
spotlight
,
sports
,
snow
,
beach
,
verylong
,
fixedfps
,
antishake
,
fireworks
.
❍
-f or --fullscreen (Fullscreen Preview)—
Makes the preview image fill the screen,
overriding any other preview option you may have set.
❍
-h or --height (Height)— Specifies the height, or vertical resolution, of the captured
image or video. This should be set to the desired height in pixels; for example, a Full
HD capture would require a height value of 1080. The minimum value is 64; the maxi-
mum depends on whether video or still images are being captured.
❍
-hf or --hflip (Horizontal Flip)—
Flips the captured image or video along its horizon-
tal axis, as though it has been viewed in a mirror.
❍
-ifx or --imxfx (Image Effects)— Enables one of a number of preconfigured special
effects on the image or video. Possible values for this option are
none
,
negative
,
solarise
,
sketch
,
denoise
,
emboss
,
oilpaint
,
hatch
,
gpen
,
pastel
,
watercolour
,
film
,
blur
,
saturation
,
colourswap
,
washedout
,
posterise
,
colourpoint
,
colourbalance
,
cartoon
,
whiteboard
,
blackboard
. These
settings can be seen in action using the Demonstration Mode option.
❍
-ISO or --ISO (ISO Sensitivity)— Sets the camera’s sensitivity to light. A lower ISO
value provides a clearer image, but requires longer exposures; a higher ISO value can
shoot at very low exposure times to capture fast-moving or badly lit subjects, but cre-
ates a ‘noisier’ image.
❍
-mm or --metering (Metering Mode)—
Sets the light metering mode for image or
video capture, which controls the automatic exposure, white balance, and ISO sensitiv-
ity options. Possible values for this option are
average
,
spot
,
backlit
,
matrix
.
❍
-n or --nopreview (No Preview)—
Does not display a preview window while captur-
ing; not required when using a timeout value of 0.
❍
-o or --output (Output File)— Sets the name of the file to be saved. The value for this
option can be either a filename, in which case the file will be created in the current direc-
tory, or an absolute path. If you are using
raspistill
or
raspivid
along with another
application that expects image data through standard input, you can divert the image or
video through standard output using a hyphen (
-
) character as the filename.