40 lines
1.1 KiB
Groff
40 lines
1.1 KiB
Groff
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.TH VIDEO 3 "3 March 2001"
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.SH NAME
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im_video_v4l1 \- various image grabbers
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.SH SYNOPSIS
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.B #include <vips/vips.h>
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.B int
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.B im_video_v4l1( IMAGE *im, const char *device, int channel,
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.B int brightness, int colour, int contrast, int hue,
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.B int ngrabs )
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.SH DESCRIPTION
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These functions grab single video frames from various devices. Which of these
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functions work depends upon how your VIPS has been configured and compiled,
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and your platform. As a result, they are far from portable ... you want a
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layer on top of these functions.
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.B im_video_v4l1(3)
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grabs a frame using Video4Linux. It grabs a 24-bit RGB colour image, at the
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maximum resolution your card allows.
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.B device
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should typically be "/dev/video".
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.B channel
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selects the channel to acquire: usually 0 is TV, and 1 is composite video.
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.B brightness,
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.B colour,
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.B contrast
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and
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.B hue
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set grab parameters. Each should be in the range (0 - 32768). 32768 is usually
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the value you want.
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.B ngrabs
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sets the number of frames the card should average. Higher values are slower,
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but typically less noisy (and slightly softer).
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.SH RETURN VALUE
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All functions return 0 on success and -1 on error.
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