Editing Image acquisition package
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The {{Forge| | The {{Forge|image_acquisition}} package is part of the [[Octave Forge]] project. | ||
There is not release package yet but you can get the source here [http://sourceforge.net/p/octave/image-acquisition/ci/default/tree/] | |||
Simply do | |||
$ hg clone http://hg.code.sf.net/p/octave/image-acquisition octave-image-acquisition | |||
$ tar czf image-acquisition.tar.gz octave-image-acquisition | |||
octave:>> pkg install image-acquisition.tar.gz | |||
If you want to report a bug see [[Image_acquisition_package#Reporting_bugs]] | |||
== Example session == | == Example session == | ||
Lines starting with | Lines starting with octave> are executed on the octave prompt. | ||
=== Load the package and list available hardware === | === Load the package and list available hardware === | ||
octave | octave> pkg load image-acquisition | ||
octave | octave> imaqhwinfo | ||
ans = | ans = | ||
scalar structure containing the fields: | scalar structure containing the fields: | ||
driver = uvcvideo | driver = uvcvideo | ||
card = UVC Camera (046d:0825) | card = UVC Camera (046d:0825) | ||
bus_info = usb-0000:00: | bus_info = usb-0000:00:16.2-2 | ||
version = 3. | version = 3.2.51 | ||
capabilities = | capabilities = 83886081 | ||
device = /dev/video0 | device = /dev/video0 | ||
=== Open the v4l2 device and output the result === | === Open the v4l2 device and output the result === | ||
octave> obj = videoinput("v4l2", "/dev/video0") | |||
octave | |||
obj = videoinput for v4l2 | obj = videoinput for v4l2 | ||
device | device = /dev/video0 | ||
driver | driver = uvcvideo | ||
card | card = UVC Camera (046d:0825) | ||
VideoInput | VideoInput = 0 | ||
VideoResolution | VideoResolution = 320 x 240 px | ||
VideoFrameInterval = 1/30 s (30.0 fps) | |||
=== Query which properties are available for the used device === | === Query which properties are available for the used device === | ||
The first 6 ones, starting with an upper letter are fixed, the other specific to the used v4l2 device. | |||
The first | octave> get(obj) | ||
octave | |||
ans = | ans = | ||
{ | { | ||
[1,1] = SelectedSourceName | [1,1] = SelectedSourceName | ||
[2,1] = | [2,1] = DeviceCapabilities | ||
[3,1] = | [3,1] = VideoInput | ||
[4,1] = | [4,1] = VideoResolution | ||
[5,1] = | [5,1] = VideoFrameInterval | ||
[6,1] = | [6,1] = VideoFormat | ||
[7,1] = | [7,1] = brightness | ||
[8,1] = | [8,1] = contrast | ||
[9,1] = | [9,1] = saturation | ||
[10,1] = | [10,1] = white_balance_temperature_auto | ||
[11,1] = | [11,1] = gain | ||
[12,1] = | [12,1] = power_line_frequency | ||
[13,1] = | [13,1] = white_balance_temperature | ||
[14,1] = | [14,1] = sharpness | ||
[15,1] = | [15,1] = backlight_compensation | ||
[16,1] = | [16,1] = exposure_auto | ||
[17,1] = | [17,1] = exposure_absolute | ||
[18 | [18,1] = exposure_auto_priority | ||
} | } | ||
=== | === Get device capabilities === | ||
octave> get(obj, "DeviceCapabilities") | |||
octave | ans = | ||
scalar structure containing the fields: | |||
driver = uvcvideo | |||
card = UVC Camera (046d:0825) | |||
bus_info = usb-0000:00:16.2-2 | |||
version = 3.2.51 | |||
capabilities = 83886081 | |||
=== List available video resolutions === | === List available video resolutions === | ||
octave> set(obj, "VideoResolution") | |||
octave | |||
ans = | ans = | ||
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=== Set the video resolution to 320x240px === | === Set the video resolution to 320x240px === | ||
octave | octave> set(obj, "VideoResolution", [320 240]) | ||
=== Get the current brightness value === | === Get the current brightness value === | ||
octave> get(obj, "brightness") | |||
octave | |||
ans = 100 | ans = 100 | ||
=== Query possible range for brightness === | === Query possible range for brightness === | ||
octave> set(obj, "brightness") | |||
octave | |||
ans = | ans = | ||
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=== Set a new value for brightness === | === Set a new value for brightness === | ||
octave> set(obj, "brightness", 100) | |||
octave | |||
=== Start preview === | === Start preview === | ||
octave> preview(obj) | |||
octave | |||
Close it with CTRL+C or with [X] on the preview window | Close it with CTRL+C or with [X] on the preview window | ||
=== Use higher resolution and start streaming with 2 buffers === | === Use higher resolution and start streaming with 2 buffers === | ||
octave> set(obj, "VideoResolution", [640 480]); | |||
octave | octave> start(obj, 2) | ||
octave | |||
=== Get an image from the buffers, view and save it === | === Get an image from the buffers, view and save it === | ||
octave> img = getsnapshot(obj); | |||
octave | octave> image(img) | ||
octave | octave> imwrite(img, "ex1_a.png") | ||
octave | octave> [img, seq, t] = getsnapshot(obj); | ||
octave> seq | |||
octave | seq = 1 | ||
octave | octave> t | ||
t = | |||
octave | |||
scalar structure containing the fields: | scalar structure containing the fields: | ||
tv_sec = | tv_sec = 19618 | ||
tv_usec = | tv_usec = 346553 | ||
=== Stop streaming === | === Stop streaming === | ||
octave> stop(obj) | |||
octave | |||
== Using v4l2loopback for tests == | == Using v4l2loopback for tests == | ||
If you don't have a v4l2 device but | If you don't have a v4l2 device but test the package you could create a loopback device: | ||
modprobe v4l2loopback | modprobe v4l2loopback | ||
gst-launch-0.10 videotestsrc ! v4l2sink device=/dev/video0 | gst-launch-0.10 videotestsrc ! v4l2sink device=/dev/video0 | ||
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There might be some warnings like "warning: function xyz shadows a built-in function" at start. | There might be some warnings like "warning: function xyz shadows a built-in function" at start. | ||
Exit octave and add libv4l2_debug.log to your bug report | Exit octave and add libv4l2_debug.log to your bug report | ||
Consider running the included tests: | Consider running the included tests: | ||
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octave> test @videoinput/set | octave> test @videoinput/set | ||
octave> test @videoinput/getsnapshot | octave> test @videoinput/getsnapshot | ||