USB Camera

Name

usb_camera - Get streaming data from USB camera

Description

KNEO Pi includes an application example named usb_camera which connects to an external USB camera and streams images into SSM buffers. Once the example is running, you can use ssm_receiver example to retrieve the streamed images from those buffers. Together, these two examples like a snapshot system—capturing and accessing real-time camera data through shared memory.

What are SSM and ssm_receiver example?

See SSM section for more details.

Synopsis

usb_camera [OPTION]

Options

-W Camera width

-H Camera height

Example

To run usb_camera, users need to give details of the camera image size.

usb_camera -W 640 -H 480

To snapshot an image streamed by the usb_camera example.

ssm_receiver -p vsrc_ssm_c_0 -o ssm_reader.yuv

How to virtualize the image?

• If you're running the example in Local Access mode (where you can see the GUI desktop), use the following command:

  ffplay -f rawvideo -pixel_format yuv420p -video_size 640x480 ssm_reader.yuv
  

• Alternatively, upload the image to an online viewer, e.g., https://codestation.ch/

Warning

The default CameraPath is set to /dev/video8 which may not be the same every time due to the timing when the webcam is connected to KNEO Pi.