1VIDEO(3) Library Functions Manual VIDEO(3)
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6 im_video_v4l1 - various image grabbers
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10 #include <vips/vips.h>
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12 int im_video_v4l1( IMAGE *im, const char *device, int channel, int
13 brightness, int colour, int contrast, int hue, int ngrabs )
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17 These functions grab single video frames from various devices. Which of
18 these functions work depends upon how your VIPS has been configured and
19 compiled, and your platform. As a result, they are far from portable
20 ... you want a layer on top of these functions.
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22 im_video_v4l1(3) grabs a frame using Video4Linux. It grabs a 24-bit RGB
23 colour image, at the maximum resolution your card allows.
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25 device should typically be "/dev/video". channel selects the channel
26 to acquire: usually 0 is TV, and 1 is composite video. brightness,
27 colour, contrast and hue set grab parameters. Each should be in the
28 range (0 - 32768). 32768 is usually the value you want. ngrabs sets
29 the number of frames the card should average. Higher values are slower,
30 but typically less noisy (and slightly softer).
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34 All functions return 0 on success and -1 on error.
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38 3 March 2001 VIDEO(3)