TechNexion USB Camera User Guide

Introduction

This article guides you how to get started using TechNexion USB camera on Windows and Linux.

Supported Camera Modules

Camera Series	Products
VCS	VCS-AR0145
VCI	VCI-AR0144 VCI-AR0234 VCI-AR0521 VCI-AR0522 VCI-AR0821 VCI-AR0822 VCI-AR1335
UVC-VLS3	UVC-VLS3-AR0144 UVC-VLS3-AR0145 UVC-VLS3-AR0234 UVC-VLS3-AR0521 UVC-VLS3-AR0522 UVC-VLS3-AR0821 UVC-VLS3-AR0822 UVC-VLS3-AR1335

More Camera Products Details...

How to use

There are several methods to use the camera when you connect it to a computer or embedded development kit via a USB cable.

Method 1 - Using TechNexion VizionViewer (Windows/Linux)

VizionViewer™

Method 2 - Using V4L2 Control (Linux)

List all devices.

$ v4l2-ctl --list-device

VCI-AR0144-C (usb-xhci-hcd.1.auto-1.2):
        /dev/video0
        /dev/video1
        /dev/media0

List camera formats.

$ v4l2-ctl -d /dev/video0 --list-formats-ext
ioctl: VIDIOC_ENUM_FMT
        Type: Video Capture

        [0]: 'UYVY' (UYVY 4:2:2)
                Size: Discrete 1280x800
                        Interval: Discrete 0.017s (60.000 fps)
                        Interval: Discrete 0.033s (30.000 fps)
                Size: Discrete 1280x720
                        Interval: Discrete 0.017s (60.000 fps)
                        Interval: Discrete 0.033s (30.000 fps)
                Size: Discrete 640x480
                        Interval: Discrete 0.017s (60.000 fps)
                        Interval: Discrete 0.033s (30.000 fps)
        [1]: 'MJPG' (Motion-JPEG, compressed)
                Size: Discrete 1280x800
                        Interval: Discrete 0.017s (60.000 fps)
                        Interval: Discrete 0.033s (30.000 fps)
                Size: Discrete 1280x720
                        Interval: Discrete 0.017s (60.000 fps)
                        Interval: Discrete 0.033s (30.000 fps)
                Size: Discrete 640x480
                        Interval: Discrete 0.017s (60.000 fps)
                        Interval: Discrete 0.033s (30.000 fps)

List camera v4l2 controls.

$ v4l2-ctl -d /dev/video0 --list-ctrls

User Controls

                brightness 0x00980900 (int)    : min=0 max=32 step=4 default=16 value=16
                        contrast 0x00980901 (int)    : min=0 max=10 step=1 default=5 value=5
                saturation 0x00980902 (int)    : min=0 max=80 step=8 default=16 value=16
        white_balance_automatic 0x0098090c (bool)   : default=1 value=1
                        gamma 0x00980910 (int)    : min=0 max=40 step=1 default=18 value=18
                        gain 0x00980913 (int)    : min=1 max=48 step=1 default=1 value=1
        power_line_frequency 0x00980918 (menu)   : min=0 max=2 default=0 value=0 (Disabled)
white_balance_temperature 0x0098091a (int)    : min=2300 max=15000 step=1 default=5000 value=5000 flags=inactive
                sharpness 0x0098091b (int)    : min=0 max=64 step=8 default=32 value=32
        backlight_compensation 0x0098091c (int)    : min=0 max=480 step=8 default=256 value=256

Camera Controls

                auto_exposure 0x009a0901 (menu)   : min=0 max=3 default=0 value=0 (Auto Mode)
        exposure_time_absolute 0x009a0902 (int)    : min=1 max=10000 step=1 default=330 value=100 flags=inactive
                pan_absolute 0x009a0908 (int)    : min=-648000 max=648000 step=3600 default=0 value=0
                tilt_absolute 0x009a0909 (int)    : min=-648000 max=648000 step=3600 default=0 value=0
                zoom_absolute 0x009a090d (int)    : min=100 max=800 step=1 default=100 value=100

Camera streaming test with UYVY format.

$ v4l2-ctl -d /dev/video0 --set-fmt-video=pixelformat=UYVY,width=1280,height=800 --stream-mmap
<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< 59.84 fps
<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< 59.85 fps

note

Using "Ctrl+C " to exit v4l2 streaming.

Camera streaming test with MJPG format.

$ v4l2-ctl -d /dev/video0 --set-fmt-video=pixelformat=MJPG,width=1280,height=800 --stream-mmap
<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< 59.84 fps
<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< 59.85 fps

note

Using "Ctrl+C " to exit v4l2 streaming.

Method 3 - Using GStreamer (Linux)

List all devices and formats.

$ gst-device-monitor-1.0

Device found:

        name  : VCI-AR0144-C
        class : Video/Source
        caps  : video/x-raw, format=UYVY, width=1280, height=800, pixel-aspect-ratio=1/1, framerate={ (fraction)60/1, (fraction)30/1 }
                video/x-raw, format=UYVY, width=1280, height=720, pixel-aspect-ratio=1/1, framerate={ (fraction)60/1, (fraction)30/1 }
                video/x-raw, format=UYVY, width=640, height=480, pixel-aspect-ratio=1/1, framerate={ (fraction)60/1, (fraction)30/1 }
                image/jpeg, parsed=true, width=1280, height=800, pixel-aspect-ratio=1/1, framerate={ (fraction)60/1, (fraction)30/1 }
                image/jpeg, parsed=true, width=1280, height=720, pixel-aspect-ratio=1/1, framerate={ (fraction)60/1, (fraction)30/1 }
                image/jpeg, parsed=true, width=640, height=480, pixel-aspect-ratio=1/1, framerate={ (fraction)60/1, (fraction)30/1 }
        properties:
                udev-probed = true
                device.bus_path = platform-xhci-hcd.1.auto-usb-0:1.2:1.0
                sysfs.path = /sys/devices/platform/soc@0/32f10108.usb/38200000.usb/xhci-hcd.1.auto/usb2/2-1/2-1.2/2-1.2:1.0/video4linux/video0
                device.bus = usb
                device.subsystem = video4linux
                device.vendor.id = 3407
                device.vendor.name = TechNexion
                device.product.id = 0144
                device.product.name = VCI-AR0144-C
                device.serial = TechNexion_VCI-AR0144-C_000000008E604600A159178868A11A1A
                device.capabilities = :capture:
                device.api = v4l2
                device.path = /dev/video0
                v4l2.device.driver = uvcvideo
                v4l2.device.card = VCI-AR0144-C
                v4l2.device.bus_info = usb-xhci-hcd.1.auto-1.2
                v4l2.device.version = 393527 (0x00060137)
                v4l2.device.capabilities = 2225078273 (0x84a00001)
                v4l2.device.device_caps = 69206017 (0x04200001)
        gst-launch-1.0 v4l2src ! ...

Preview with UYVY format.

$ gst-launch-1.0 v4l2src device=/dev/video0 ! "video/x-raw, format=(string)UYVY, width=(int)1280, height=(int)800" ! videoconvert ! autovideosink sync=false

Preview with MJPG format.

$ gst-launch-1.0 v4l2src device=/dev/video0 ! "image/jpeg, width=(int)1280, height=(int)800" ! jpegdec ! autovideosink sync=false

note

GStreamer element
The element depends on your system, so the example may not be suitable for your system.

Troubleshooting

Auto-suspend

Since the camera's standby power consumption is low, the system may disconnect camera through the auto-suspend function as like below.

[86452.959044] usb 2-1.2: new SuperSpeed USB device number 5 using xhci-hcd
[86452.983505] usb 2-1.2: LPM exit latency is zeroed, disabling LPM.
[86453.022662] usb 2-1.2: Found UVC 1.10 device VCI-AR0144-C (3407:0144)
[86453.139540] input: VCI-AR0144-C as /devices/platform/soc@0/32f10108.usb/38200000.usb/xhci-hcd.1.auto/usb2/2-1/2-1.2/2-1.2:1.0/input/input8
[86467.470212] usb 2-1.2: USB disconnect, device number 5
[86468.959511] usb 2-1.2: new SuperSpeed USB device number 6 using xhci-hcd
[86468.983960] usb 2-1.2: LPM exit latency is zeroed, disabling LPM.
[86469.022673] usb 2-1.2: Found UVC 1.10 device VCI-AR0144-C (3407:0144)
[86469.139501] input: VCI-AR0144-C as /devices/platform/soc@0/32f10108.usb/38200000.usb/xhci-hcd.1.auto/usb2/2-1/2-1.2/2-1.2:1.0/input/input9
[86472.078213] usb 2-1.2: USB disconnect, device number 6

You can first check flag of auto-suspend and modify it to turn off this function.

$ cat /sys/module/usbcore/parameters/autosuspend
2

$ echo -1 > /sys/module/usbcore/parameters/autosuspend

After turning off auto-suspend, you need to reconnect the camera.

Floating framerate

Because of the product feature "Designed for Low Light Applications ", the camera will increase exposure time via automatic exposure mode to maintain image quality in low-light environment. You can change the camera to manual exposure mode to keep the framerate. However, if you increase exposure gain in low-light environment, you will see more noise.

$ v4l2-ctl -d /dev/video0 --set-ctrl auto_exposure=1

The other way, you can use VizionViewer™ or VizionCTL to change to AGC mode (Auto gain control, Manual exposure time).

Camera Firmware Issues

If you encounter camera firmware-related problems or need to restore factory settings, please refer to the USB Camera Factory Recondition Tool for detailed instructions on how to recondition and restore your camera to factory defaults.

Camera issue on NVIDIA JetPack

On NVIDIA Jetson platforms, a UVC camera stream may freeze, stop after several frames, or show frame corruption when streaming high-resolution or high-bandwidth video. This issue can be caused by insufficient UVC transfer buffers in the uvcvideo kernel driver.

The solution is to rebuild the uvcvideo kernel module with larger UVC_URBS and UVC_MAX_PACKETS values, then replace the module on the Jetson system.

caution

The following steps replace a Linux kernel module on the target system. Build and install the module on the same Jetson device and JetPack/L4T version where the camera will be used.

Verified Environment

We verified this solution on JetPack 6.2.x. For other JetPack versions, use the same procedure but download the BSP source package that matches the Jetson Linux/L4T version installed on the target device.

The following JetPack 6.2.x packages are verified examples:

JetPack version	L4T version	BSP source package
JetPack 6.2	R36.4.3	`https://developer.nvidia.com/downloads/embedded/l4t/r36_release_v4.3/sources/public_sources.tbz2`
JetPack 6.2.1	R36.4.4	`https://developer.nvidia.com/downloads/embedded/l4t/r36_release_v4.4/sources/public_sources.tbz2`

For other JetPack/L4T versions, go to the NVIDIA Jetson Linux Archive, open the page for the matching Jetson Linux release, and download Sources > Driver Package (BSP) Sources.

Build and Install uvcvideo Module

Check the JetPack/L4T version.

$ cat /etc/nv_tegra_release

Install build dependencies.

$ sudo apt-get update
$ sudo apt-get install -y libssl-dev build-essential pkg-config libncurses-dev lbzip2

Download and extract the NVIDIA kernel source.

Replace <BSP_SOURCE_URL> with the BSP source URL that matches your L4T version.

$ mkdir -p ~/uvc_driver/build_dir
$ cd ~/uvc_driver
$ wget "<BSP_SOURCE_URL>" -O public_sources.tbz2
$ tar -xf public_sources.tbz2
$ cd Linux_for_Tegra/source/
$ tar -xf kernel_src.tbz2
$ cd kernel/kernel-jammy-src/

Update the UVC driver buffer settings.

$ sed -i -e '/#define DRIVER_VERSION/ s/"\(.*\)"/"\1-tn1"/' drivers/media/usb/uvc/uvcvideo.h
$ sed -i -e 's/#define UVC_URBS.*/#define UVC_URBS                1000/' drivers/media/usb/uvc/uvcvideo.h
$ sed -i -e 's/#define UVC_MAX_PACKETS.*/#define UVC_MAX_PACKETS         64/' drivers/media/usb/uvc/uvcvideo.h

Prepare the kernel build configuration.

$ if [ -f /proc/config.gz ]; then \
    zcat /proc/config.gz > ~/uvc_driver/build_dir/.config; \
  else \
    cp /boot/config-$(uname -r) ~/uvc_driver/build_dir/.config; \
  fi
$ make ARCH=arm64 O=~/uvc_driver/build_dir olddefconfig
$ make ARCH=arm64 O=~/uvc_driver/build_dir modules_prepare

Build the UVC driver module.

$ make ARCH=arm64 O=~/uvc_driver/build_dir M=$PWD/drivers/media/usb/uvc modules

After the build completes, the new module should be available at:

drivers/media/usb/uvc/uvcvideo.ko

Back up the original module and install the rebuilt module.

Make sure the camera application is stopped before replacing the driver.

$ sudo cp -av /lib/modules/$(uname -r)/kernel/drivers/media/usb/uvc/uvcvideo.ko \
    /lib/modules/$(uname -r)/kernel/drivers/media/usb/uvc/uvcvideo.ko.backup
$ sudo install -m 0644 drivers/media/usb/uvc/uvcvideo.ko \
    /lib/modules/$(uname -r)/kernel/drivers/media/usb/uvc/uvcvideo.ko
$ sudo depmod -a
$ sudo reboot

Verify the installed module.

After reboot, confirm that the installed uvcvideo module version includes the -tn1 suffix.

$ modinfo /lib/modules/$(uname -r)/kernel/drivers/media/usb/uvc/uvcvideo.ko | grep '^version:'
version:        1.1.1-tn1

Then run a camera streaming test again:

$ v4l2-ctl -d /dev/video0 --stream-mmap --stream-count=100

Reference

Windows Laptop streaming Issue

When using UVC cameras on Windows laptops, intermittent frame freezing may occur during UYVY video streaming. This behavior is caused by Windows power-saving features, such as CPU C-states and USB selective suspend, which can slow down USB interrupt handling.

To resolve this issue, manually disable CPU C-states and USB selective suspend on your Windows system. These settings must be configured before starting the stream to ensure stable performance.

Disable power-saving settings (before streaming):

Download disable_pwr_setting.reg, then run the following commands in PowerShell to apply the registry settings that disable CPU C-states and USB selective suspend:

# Import the registry file silently without confirmation dialog
# Using -Wait ensures the registry update is finished before the next step
Start-Process -FilePath "regedit.exe" -ArgumentList "/s", "disable_pwr_setting.reg" -Wait

# Force Windows to reload the current power scheme to apply changes immediately
powercfg -setactive scheme_current

Restore power-saving settings (after streaming):

Download restore_pwr_setting.reg, then run the following commands to restore the original power settings:

# Import the registry file silently without confirmation dialog
Start-Process -FilePath "regedit.exe" -ArgumentList "/s", "restore_pwr_setting.reg" -Wait

# Force Windows to reload the current power scheme to apply changes immediately
powercfg -setactive scheme_current

Introduction​

Supported Camera Modules​

How to use​

Method 1 - Using TechNexion VizionViewer (Windows/Linux)​

Method 2 - Using V4L2 Control (Linux)​

Method 3 - Using GStreamer (Linux)​

Troubleshooting​

Auto-suspend​

Floating framerate​

Camera Firmware Issues​

Camera issue on NVIDIA JetPack​

Verified Environment​

Build and Install uvcvideo Module​

Reference​

Windows Laptop streaming Issue​

Introduction

Supported Camera Modules

How to use

Method 1 - Using TechNexion VizionViewer (Windows/Linux)

Method 2 - Using V4L2 Control (Linux)

Method 3 - Using GStreamer (Linux)

Troubleshooting

Auto-suspend

Floating framerate

Camera Firmware Issues

Camera issue on NVIDIA JetPack

Verified Environment

Build and Install uvcvideo Module

Reference

Windows Laptop streaming Issue