$ strace -e open,close ./ko 1

Test interval: 1
v4l2src name=gc-v4l2-src device=/dev/video0 ! video/x-raw,framerate=24/1,width=640,height=480 ! xvimagesink ---> 0
 ---> 1
 ---> 2
 ---> 3
 ---> 4
 ---> 5
Error waiting 1 sec

open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
close(3)                                = 0
open("/usr/lib/x86_64-linux-gnu/libgstreamer-1.0.so.0", O_RDONLY|O_CLOEXEC) = 3
close(3)                                = 0
open("/lib/x86_64-linux-gnu/libpthread.so.0", O_RDONLY|O_CLOEXEC) = 3
close(3)                                = 0
open("/lib/x86_64-linux-gnu/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
close(3)                                = 0
open("/usr/lib/x86_64-linux-gnu/libgobject-2.0.so.0", O_RDONLY|O_CLOEXEC) = 3
close(3)                                = 0
open("/usr/lib/x86_64-linux-gnu/libgmodule-2.0.so.0", O_RDONLY|O_CLOEXEC) = 3
close(3)                                = 0
open("/lib/x86_64-linux-gnu/libglib-2.0.so.0", O_RDONLY|O_CLOEXEC) = 3
close(3)                                = 0
open("/lib/x86_64-linux-gnu/libm.so.6", O_RDONLY|O_CLOEXEC) = 3
close(3)                                = 0
open("/lib/x86_64-linux-gnu/librt.so.1", O_RDONLY|O_CLOEXEC) = 3
close(3)                                = 0
open("/lib/x86_64-linux-gnu/libdl.so.2", O_RDONLY|O_CLOEXEC) = 3
close(3)                                = 0
open("/usr/lib/x86_64-linux-gnu/libffi.so.6", O_RDONLY|O_CLOEXEC) = 3
close(3)                                = 0
open("/lib/x86_64-linux-gnu/libpcre.so.3", O_RDONLY|O_CLOEXEC) = 3
close(3)                                = 0
open("/home/alfro/.cache/gstreamer-1.0/registry.x86_64.bin", O_RDONLY) = 3
close(3)                                = 0
open("/home/alfro/.local/share/gstreamer-1.0/plugins", O_RDONLY|O_NONBLOCK|O_DIRECTORY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
open("/usr/lib/x86_64-linux-gnu/charset.alias", O_RDONLY) = -1 ENOENT (No such file or directory)
open("/usr/lib/x86_64-linux-gnu/gconv/gconv-modules.cache", O_RDONLY) = 3
close(3)                                = 0
open("/usr/lib/x86_64-linux-gnu/gstreamer-1.0", O_RDONLY|O_NONBLOCK|O_DIRECTORY|O_CLOEXEC) = 3
open("/home/alfro/.frei0r-1/lib", O_RDONLY|O_NONBLOCK|O_DIRECTORY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
open("/usr/lib/x86_64-linux-gnu/frei0r-1", O_RDONLY|O_NONBLOCK|O_DIRECTORY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
open("/usr/lib/frei0r-1", O_RDONLY|O_NONBLOCK|O_DIRECTORY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
open("/usr/local/lib/frei0r-1", O_RDONLY|O_NONBLOCK|O_DIRECTORY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
open("/usr/lib32/frei0r-1", O_RDONLY|O_NONBLOCK|O_DIRECTORY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
open("/usr/local/lib32/frei0r-1", O_RDONLY|O_NONBLOCK|O_DIRECTORY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
open("/usr/lib64/frei0r-1", O_RDONLY|O_NONBLOCK|O_DIRECTORY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
open("/usr/local/lib64/frei0r-1", O_RDONLY|O_NONBLOCK|O_DIRECTORY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
open("/dev", O_RDONLY|O_NONBLOCK|O_DIRECTORY|O_CLOEXEC) = 4
close(4)                                = 0
open("/dev/v4l2", O_RDONLY|O_NONBLOCK|O_DIRECTORY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
open("/usr/lib/x86_64-linux-gnu/gstreamer-1.0/include", O_RDONLY|O_NONBLOCK|O_DIRECTORY|O_CLOEXEC) = 4
open("/usr/lib/x86_64-linux-gnu/gstreamer-1.0/include/gst", O_RDONLY|O_NONBLOCK|O_DIRECTORY|O_CLOEXEC) = 5
open("/usr/lib/x86_64-linux-gnu/gstreamer-1.0/include/gst/gl", O_RDONLY|O_NONBLOCK|O_DIRECTORY|O_CLOEXEC) = 6
close(6)                                = 0
close(5)                                = 0
close(4)                                = 0
close(3)                                = 0
open("/usr/lib/x86_64-linux-gnu/gstreamer-1.0/libgstvideo4linux2.so", O_RDONLY|O_CLOEXEC) = 3
close(3)                                = 0
open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
close(3)                                = 0
open("/usr/lib/x86_64-linux-gnu/libgstallocators-1.0.so.0", O_RDONLY|O_CLOEXEC) = 3
close(3)                                = 0
open("/usr/lib/x86_64-linux-gnu/libgstvideo-1.0.so.0", O_RDONLY|O_CLOEXEC) = 3
close(3)                                = 0
open("/usr/lib/x86_64-linux-gnu/libgstbase-1.0.so.0", O_RDONLY|O_CLOEXEC) = 3
close(3)                                = 0
open("/usr/lib/x86_64-linux-gnu/libv4l2.so.0", O_RDONLY|O_CLOEXEC) = 3
close(3)                                = 0
open("/usr/lib/x86_64-linux-gnu/libgudev-1.0.so.0", O_RDONLY|O_CLOEXEC) = 3
close(3)                                = 0
open("/usr/lib/x86_64-linux-gnu/liborc-0.4.so.0", O_RDONLY|O_CLOEXEC) = 3
close(3)                                = 0
open("/usr/lib/x86_64-linux-gnu/libv4lconvert.so.0", O_RDONLY|O_CLOEXEC) = 3
close(3)                                = 0
open("/lib/x86_64-linux-gnu/libudev.so.1", O_RDONLY|O_CLOEXEC) = 3
close(3)                                = 0
open("/usr/lib/x86_64-linux-gnu/libjpeg.so.8", O_RDONLY|O_CLOEXEC) = 3
close(3)                                = 0
open("/usr/lib/x86_64-linux-gnu/gstreamer-1.0/libgstxvimagesink.so", O_RDONLY|O_CLOEXEC) = 3
close(3)                                = 0
open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
close(3)                                = 0
open("/usr/lib/x86_64-linux-gnu/libX11.so.6", O_RDONLY|O_CLOEXEC) = 3
close(3)                                = 0
open("/usr/lib/x86_64-linux-gnu/libXv.so.1", O_RDONLY|O_CLOEXEC) = 3
close(3)                                = 0
open("/usr/lib/x86_64-linux-gnu/libXext.so.6", O_RDONLY|O_CLOEXEC) = 3
close(3)                                = 0
open("/usr/lib/x86_64-linux-gnu/libxcb.so.1", O_RDONLY|O_CLOEXEC) = 3
close(3)                                = 0
open("/usr/lib/x86_64-linux-gnu/libXau.so.6", O_RDONLY|O_CLOEXEC) = 3
close(3)                                = 0
open("/usr/lib/x86_64-linux-gnu/libXdmcp.so.6", O_RDONLY|O_CLOEXEC) = 3
close(3)                                = 0
open("/usr/lib/x86_64-linux-gnu/gstreamer-1.0/libgstcoreelements.so", O_RDONLY|O_CLOEXEC) = 5
close(5)                                = 0
open("/home/alfro/.Xauthority", O_RDONLY) = 6
close(6)                                = 0
open("/dev/video0", O_RDWR)             = 6
open("/usr/lib/x86_64-linux-gnu/libv4l/plugins", O_RDONLY|O_NONBLOCK|O_DIRECTORY|O_CLOEXEC) = 7
close(7)                                = 0
open("/usr/lib/x86_64-linux-gnu/libv4l/plugins/libv4l-mplane.so", O_RDONLY|O_CLOEXEC) = 7
close(7)                                = 0
open("/sys/class/video4linux/video0/dev", O_RDONLY) = 7
close(7)                                = 0
open("/sys/class/video4linux/video0/device/modalias", O_RDONLY) = 7
close(7)                                = 0
open("/sys/class/video4linux/video0/device/../speed", O_RDONLY) = 7
close(7)                                = 0
open("/sys/class/dmi/id/sys_vendor", O_RDONLY) = 7
close(7)                                = 0
open("/sys/class/dmi/id/product_name", O_RDONLY) = 7
close(7)                                = 0
open("/sys/class/dmi/id/product_version", O_RDONLY) = 7
close(7)                                = 0
open("/sys/class/dmi/id/board_vendor", O_RDONLY) = 7
close(7)                                = 0
open("/sys/class/dmi/id/board_name", O_RDONLY) = 7
close(7)                                = 0
open("/sys/class/dmi/id/board_version", O_RDONLY) = 7
close(7)                                = 0
close(12)                               = 0
close(11)                               = 0
close(10)                               = 0
close(9)                                = 0
close(14)                               = 0
close(13)                               = 0
close(5)                                = 0
close(6)                                = 0
close(4)                                = 0
close(3)                                = 0
open("/home/alfro/.Xauthority", O_RDONLY) = 6
close(6)                                = 0
open("/dev/video0", O_RDWR)             = 6
open("/usr/lib/x86_64-linux-gnu/libv4l/plugins", O_RDONLY|O_NONBLOCK|O_DIRECTORY|O_CLOEXEC) = 9
close(9)                                = 0
open("/usr/lib/x86_64-linux-gnu/libv4l/plugins/libv4l-mplane.so", O_RDONLY|O_CLOEXEC) = 9
close(9)                                = 0
open("/sys/class/video4linux/video0/dev", O_RDONLY) = 9
close(9)                                = 0
open("/sys/class/video4linux/video0/device/modalias", O_RDONLY) = 9
close(9)                                = 0
open("/sys/class/video4linux/video0/device/../speed", O_RDONLY) = 9
close(9)                                = 0
open("/sys/class/dmi/id/sys_vendor", O_RDONLY) = 9
close(9)                                = 0
open("/sys/class/dmi/id/product_name", O_RDONLY) = 9
close(9)                                = 0
open("/sys/class/dmi/id/product_version", O_RDONLY) = 9
close(9)                                = 0
open("/sys/class/dmi/id/board_vendor", O_RDONLY) = 9
close(9)                                = 0
open("/sys/class/dmi/id/board_name", O_RDONLY) = 9
close(9)                                = 0
open("/sys/class/dmi/id/board_version", O_RDONLY) = 9
close(9)                                = 0
close(12)                               = 0
close(11)                               = 0
close(10)                               = 0
close(9)                                = 0
close(14)                               = 0
close(13)                               = 0
close(5)                                = 0
close(6)                                = 0
close(4)                                = 0
close(3)                                = 0
open("/home/alfro/.Xauthority", O_RDONLY) = 6
close(6)                                = 0
open("/dev/video0", O_RDWR)             = 6
open("/usr/lib/x86_64-linux-gnu/libv4l/plugins", O_RDONLY|O_NONBLOCK|O_DIRECTORY|O_CLOEXEC) = 9
close(9)                                = 0
open("/usr/lib/x86_64-linux-gnu/libv4l/plugins/libv4l-mplane.so", O_RDONLY|O_CLOEXEC) = 9
close(9)                                = 0
open("/sys/class/video4linux/video0/dev", O_RDONLY) = 9
close(9)                                = 0
open("/sys/class/video4linux/video0/device/modalias", O_RDONLY) = 9
close(9)                                = 0
open("/sys/class/video4linux/video0/device/../speed", O_RDONLY) = 9
close(9)                                = 0
open("/sys/class/dmi/id/sys_vendor", O_RDONLY) = 9
close(9)                                = 0
open("/sys/class/dmi/id/product_name", O_RDONLY) = 9
close(9)                                = 0
open("/sys/class/dmi/id/product_version", O_RDONLY) = 9
close(9)                                = 0
open("/sys/class/dmi/id/board_vendor", O_RDONLY) = 9
close(9)                                = 0
open("/sys/class/dmi/id/board_name", O_RDONLY) = 9
close(9)                                = 0
open("/sys/class/dmi/id/board_version", O_RDONLY) = 9
close(9)                                = 0
close(12)                               = 0
close(11)                               = 0
close(10)                               = 0
close(9)                                = 0
close(14)                               = 0
close(13)                               = 0
close(5)                                = 0
close(6)                                = 0
close(4)                                = 0
close(3)                                = 0
open("/home/alfro/.Xauthority", O_RDONLY) = 6
close(6)                                = 0
open("/dev/video0", O_RDWR)             = 6
open("/usr/lib/x86_64-linux-gnu/libv4l/plugins", O_RDONLY|O_NONBLOCK|O_DIRECTORY|O_CLOEXEC) = 9
close(9)                                = 0
open("/usr/lib/x86_64-linux-gnu/libv4l/plugins/libv4l-mplane.so", O_RDONLY|O_CLOEXEC) = 9
close(9)                                = 0
open("/sys/class/video4linux/video0/dev", O_RDONLY) = 9
close(9)                                = 0
open("/sys/class/video4linux/video0/device/modalias", O_RDONLY) = 9
close(9)                                = 0
open("/sys/class/video4linux/video0/device/../speed", O_RDONLY) = 9
close(9)                                = 0
open("/sys/class/dmi/id/sys_vendor", O_RDONLY) = 9
close(9)                                = 0
open("/sys/class/dmi/id/product_name", O_RDONLY) = 9
close(9)                                = 0
open("/sys/class/dmi/id/product_version", O_RDONLY) = 9
close(9)                                = 0
open("/sys/class/dmi/id/board_vendor", O_RDONLY) = 9
close(9)                                = 0
open("/sys/class/dmi/id/board_name", O_RDONLY) = 9
close(9)                                = 0
open("/sys/class/dmi/id/board_version", O_RDONLY) = 9
close(9)                                = 0
close(12)                               = 0
close(11)                               = 0
close(10)                               = 0
close(9)                                = 0
close(14)                               = 0
close(13)                               = 0
close(5)                                = 0
close(6)                                = 0
close(4)                                = 0
close(3)                                = 0
open("/home/alfro/.Xauthority", O_RDONLY) = 6
close(6)                                = 0
open("/dev/video0", O_RDWR)             = 6
open("/usr/lib/x86_64-linux-gnu/libv4l/plugins", O_RDONLY|O_NONBLOCK|O_DIRECTORY|O_CLOEXEC) = 9
close(9)                                = 0
open("/usr/lib/x86_64-linux-gnu/libv4l/plugins/libv4l-mplane.so", O_RDONLY|O_CLOEXEC) = 9
close(9)                                = 0
open("/sys/class/video4linux/video0/dev", O_RDONLY) = 9
close(9)                                = 0
open("/sys/class/video4linux/video0/device/modalias", O_RDONLY) = 9
close(9)                                = 0
open("/sys/class/video4linux/video0/device/../speed", O_RDONLY) = 9
close(9)                                = 0
open("/sys/class/dmi/id/sys_vendor", O_RDONLY) = 9
close(9)                                = 0
open("/sys/class/dmi/id/product_name", O_RDONLY) = 9
close(9)                                = 0
open("/sys/class/dmi/id/product_version", O_RDONLY) = 9
close(9)                                = 0
open("/sys/class/dmi/id/board_vendor", O_RDONLY) = 9
close(9)                                = 0
open("/sys/class/dmi/id/board_name", O_RDONLY) = 9
close(9)                                = 0
open("/sys/class/dmi/id/board_version", O_RDONLY) = 9
close(9)                                = 0
close(12)                               = 0
close(11)                               = 0
close(10)                               = 0
close(9)                                = 0
close(14)                               = 0
close(13)                               = 0
close(5)                                = 0
close(4)                                = 0
close(3)                                = 0
open("/home/alfro/.Xauthority", O_RDONLY) = 9
close(9)                                = 0
open("/dev/video0", O_RDWR)             = 9
open("/usr/lib/x86_64-linux-gnu/libv4l/plugins", O_RDONLY|O_NONBLOCK|O_DIRECTORY|O_CLOEXEC) = 10
close(10)                               = 0
open("/usr/lib/x86_64-linux-gnu/libv4l/plugins/libv4l-mplane.so", O_RDONLY|O_CLOEXEC) = 10
close(10)                               = 0
open("/sys/class/video4linux/video0/dev", O_RDONLY) = 10
close(10)                               = 0
open("/sys/class/video4linux/video0/device/modalias", O_RDONLY) = 10
close(10)                               = 0
open("/sys/class/video4linux/video0/device/../speed", O_RDONLY) = 10
close(10)                               = 0
open("/sys/class/dmi/id/sys_vendor", O_RDONLY) = 10
close(10)                               = 0
open("/sys/class/dmi/id/product_name", O_RDONLY) = 10
close(10)                               = 0
open("/sys/class/dmi/id/product_version", O_RDONLY) = 10
close(10)                               = 0
open("/sys/class/dmi/id/board_vendor", O_RDONLY) = 10
close(10)                               = 0
open("/sys/class/dmi/id/board_name", O_RDONLY) = 10
close(10)                               = 0
open("/sys/class/dmi/id/board_version", O_RDONLY) = 10
close(10)                               = 0
libv4l2: error setting pixformat: Device or resource busy
+++ exited with 255 +++
