Introduction

The Video4Linux-API (V4L in short) is the Linux interface that is used to manage the CSI video input from the CSI-Camera. Most of those cameras are using I2C for futher configurations for the camera, which can be changed over the V4L-API in the following ways.

 test@test-desktop:~$ sudo apt update & sudo apt install v4l-utils

Video4Linux Controls

V4L allows the user to make further configurations on the Camera sensor to alter/improve the video stream settings.

The video device can be found in the /dev/ directory. If the camera correctly plugged in then there should be a device called /dev/videoX, where X is the camera id.

List available controls

Returns a list of available camera controls to change

Syntax: sudo v4l2-ctl --device /dev/videoX -l

test@test-desktop:~$ sudo v4l2-ctl --device /dev/video0 -l

Camera Controls

                     group_hold 0x009a2003 (bool)   : default=0 value=0 flags=execute-on-write
                    sensor_mode 0x009a2008 (int64)  : min=0 max=3 step=1 default=0 value=1 flags=slider
                           gain 0x009a2009 (int64)  : min=16 max=356 step=1 default=16 value=16 flags=slider
                       exposure 0x009a200a (int64)  : min=13 max=683709 step=1 default=2495 value=26011 flags=slider
                     frame_rate 0x009a200b (int64)  : min=2000000 max=60000000 step=1 default=60000000 value=21000000 flags=slider
                    bypass_mode 0x009a2064 (intmenu): min=0 max=1 default=0 value=1
                override_enable 0x009a2065 (intmenu): min=0 max=1 default=0 value=1
                   height_align 0x009a2066 (int)    : min=1 max=16 step=1 default=1 value=1
                     size_align 0x009a2067 (intmenu): min=0 max=2 default=0 value=0
               write_isp_format 0x009a2068 (int)    : min=1 max=1 step=1 default=1 value=1
       sensor_signal_properties 0x009a2069 (u32)    : min=0 max=4294967295 step=1 default=0 [30][18] flags=read-only, has-payload
        sensor_image_properties 0x009a206a (u32)    : min=0 max=4294967295 step=1 default=0 [30][16] flags=read-only, has-payload
      sensor_control_properties 0x009a206b (u32)    : min=0 max=4294967295 step=1 default=0 [30][36] flags=read-only, has-payload
              sensor_dv_timings 0x009a206c (u32)    : min=0 max=4294967295 step=1 default=0 [30][16] flags=read-only, has-payload
               low_latency_mode 0x009a206d (bool)   : default=0 value=0
               preferred_stride 0x009a206e (int)    : min=0 max=65535 step=1 default=0 value=0
                   sensor_modes 0x009a2082 (int)    : min=0 max=30 step=1 default=30 value=3 flags=read-only
test@test-desktop:~$ 

Set control value

For this example we use the exposure controls from the list above

exposure 0x009a200a (int64)  : min=13 max=683709 step=1 default=2495 value=26011 flags=slider

This control can be changed by using the following command Syntax: sudo v4l2-ctl --device /dev/videoX --set-ctrl=<control>=<value>

test@test-desktop:~$ sudo v4l2-ctl --device /dev/video0 --set-ctrl=exposure=600000

Get control value

For this example we use the exposure controls from the list above.

This control can be read by using the following command Syntax: sudo v4l2-ctl --device /dev/videoX --get-ctrl=<control>

test@test-desktop:~$ sudo v4l2-ctl --device /dev/video0 --get-ctrl=exposure
exposure: 19999

Example Stream

The following screenshots are showing the difference between different exposure settings on a Raspberry PI IMX477 camera sensor that is connected via CSI on our JNX30M Carrierboard

How to connect

Most of carrierboards are using a 22-Pin FPC/FFC connector. The images below are showing the camera connection for the camera on a JNX30 Carrierboard using a 15- to 22-Pin adapter .

Camera Capture

The parameter sensor-id= describes the camera target. This id can be found by using ls /dev/. If the camera correctly plugged in then there should be a device called /dev/videoX, where X is the camera id.

All pipelines listed below are using the NVIDIA accelerated Argus GStreamer-plugins to make use of the NVIDIA Jetson specific hardware components

Common properties

Capture examples

Document revisions and changes

What is CSI?

CSI (Camera Serial Interface) is a specification for the transmission of video data from a camera sensor to a processor or other device. It is commonly used in embedded and mobile systems for a low latency video input.

• Q: Is the camera sensor <insert_sensor_name_here> supported by your firmware?

  • A: Our default firmware currently only supports the . If you need further support with a different camera, you may want to contact us (support@auvidea.eu)

• Q: My custom camera does not work on your board?

  • A: You may want to contact your camera vendor, if he already supports our carrierboard with their camera. If not, you may want to contact us (support@auvidea.eu)

• Q: Why doesn't my IMX219 sensor on your Carrierboard?

  • A: Its required to install a custom firmware on the Jetson to support our carrierboards properly. You can find the downloads for our image on our

• Q: I have installed your firmware, but my IMX219 sensor still does not work.

  • A: Please make sure that you have connected the camera properly to your carrierboard. You may want to reach out to us, If the camera still does not work (support@auvidea.eu)

• Q: How is the CSI-Connector configured on your carrierboard?

  • A: You can find a more detailed description of the CSI-Connectors in the manual on our of your carrierboard