How to make the CSI camera on the Raspberry Pi work?

[iGmainC]

My camera is the Raspberry Pi NolR camera V2, and the camera is connected to the Raspberry Pi through the CSI interface.
I get the following error when I run the python code:

import cv2

cap = cv2.VideoCapture(10)
cap.set(3,1920)
cap.set(4,1080)

cap.release()
cv2.destroyAllWindows()

[ WARN:0] global /build/opencv/src/opencv-4.4.0/modules/videoio/src/cap_gstreamer.cpp (480) isPipelinePlaying OpenCV | GStreamer warning: GStreamer: pipeline have not been created
[ WARN:0] global /build/opencv/src/opencv-4.4.0/modules/videoio/src/cap_v4l.cpp (893) open VIDEOIO(V4L2:/dev/video10): can't open camera by index

The contents of my /dev directory are as follows:

autofs           dri        input  loop7         null   ram14   raw             tty    tty18  tty28  tty38  tty48  tty58    ttyprintk  vcs3   vcsm-cma     video10
block            fb0        kmsg   loop-control  port   ram15   rfkill          tty0   tty19  tty29  tty39  tty49  tty59    uhid       vcs4   vcsu         video11
btrfs-control    fd         kvm    mapper        ppp    ram2    rpivid-h264mem  tty1   tty2   tty3   tty4   tty5   tty6     uinput     vcs5   vcsu1        video12
bus              full       log    media0        ptmx   ram3    rpivid-hevcmem  tty10  tty20  tty30  tty40  tty50  tty60    urandom    vcs6   vcsu2        video13
cachefiles       fuse       loop0  media1        pts    ram4    rpivid-intcmem  tty11  tty21  tty31  tty41  tty51  tty61    v4l        vcsa   vcsu3        video14
char             gpiochip0  loop1  mem           ram0   ram5    rpivid-vp9mem   tty12  tty22  tty32  tty42  tty52  tty62    vchiq      vcsa1  vcsu4        video15
console          gpiochip1  loop2  mmcblk0       ram1   ram6    shm             tty13  tty23  tty33  tty43  tty53  tty63    vcio       vcsa2  vcsu5        video16
cpu_dma_latency  gpiomem    loop3  mmcblk0p1     ram10  ram7    snd             tty14  tty24  tty34  tty44  tty54  tty7     vc-mem     vcsa3  vcsu6        watchdog
cuse             hidraw0    loop4  mmcblk0p2     ram11  ram8    stderr          tty15  tty25  tty35  tty45  tty55  tty8     vcs        vcsa4  vga_arbiter  watchdog0
disk             hidraw1    loop5  mqueue        ram12  ram9    stdin           tty16  tty26  tty36  tty46  tty56  tty9     vcs1       vcsa5  vhci         zero
dma_heap         hwrng      loop6  net           ram13  random  stdout          tty17  tty27  tty37  tty47  tty57  ttyAMA0  vcs2       vcsa6  vhost-net    zram0

What should I do to make the camera work properly?

[Jtyle6]

What way is the cable facing?

https://www.raspberrypi.org/documentation/usage/camera/

[iGmainC]

The cable facing is of course correct.
There is no video0 in /dev, but there are video10 to video16.
It is a pity that video10 to video16 are not valid.
I guess there may be no CSI related driver in the system, but I don’t know where to find it.

[iGmainC]

The camera equipment is no problem.
I can use it normally in Raspberry Pi OS.

[Darksky]

Put start_x=1 in /boot/config.txt and reboot.

[Jtyle6]

Thanks. I Was starting to scratch my head. About this…

[iGmainC]

Now the camera is working, but the image it transmits is strange (I am very sure that the camera is not damaged), like this:

This strange picture will flicker and will not be displayed continuously.
At the same time there will be some information:

[ WARN:0] global /build/opencv/src/opencv-4.4.0/modules/videoio/src/cap_gstreamer.cpp (480) isPipelinePlaying OpenCV | GStreamer warning: GStreamer: pipeline have not been created

Can recompiling opencv solve this problem?
In other words, what should I do to solve this problem?

[Darksky]

I have no clue. I do not have a camera and know nothing about opencv. I do know some others here have gotten their camera’s working.

[iGmainC]

Well, I will try to solve this problem.
Thank you very much for your answers.

[iGmainC]

I solved this problem.

1. If there is no video0 in the /dev directory, you need to add start_x=1 in /boot/config.txt.
2. The screen flickers because the camera’s resolution setting is incorrect. The Raspberry Pi Camera V2 (8 million pixels) only supports the ratio of 4:3 (it should be), and the camera can work normally when the resolution is 1024×768.

Thank you @Darksky and @Jtyle6 for helping me.

---

我解决这个问题了

1. 在/dev目录下没有video0的，需要在/boot/config.txt中添加start_x=1
2. 出现画面闪烁是因为没有设置正确的摄像头的分辨率，Raspberry Pi camera V2（800万像素的）只支持4:3的比例（应该是这样），使用1024×768的分辨率时摄像头就能正常工作了（或者2048×1536，只要宽高比是4:3的分辨率，并且总像素在800万像素以下的应该都可以）

感谢帮我解决问题的 @Darksky 和 @Jtyle6。