Using USB camera

Take photos and videos on your Raspberry Pi using a standard USB camera.

Install FSWebcam

FSWebcam is a simple and clear webcam application. The software installation command is as follows:

xxxxxxxxxx
sudo apt install fswebcam

• Add user permissions: sudo usermod -a -G video

Example: Add pi user permissions to the group

xxxxxxxxxx
sudo usermod -a -G video pi

• Check if the user has been added to the group correctly

  Command: groups

View USB camera device

Use the lsusb command to view all USB devices recognized by the system;

Use the ls /dev/video* command to list all video devices recognized by the system.

xxxxxxxxxx
The next two commands are to detect the information displayed by the camera. You can compare the differences by yourself:
One is image/video collection and the other is metadata collection.

Photograph

• fswebcam <image_name>

Example: Take a photo and save it as image.jpg (the file saving path defaults to the user directory)

xxxxxxxxxx
fswebcam image.jpg

• fswebcam -r resolution <image_name>

Example: Take an image file with a resolution of 1280x720 and save it as image2.jpg

xxxxxxxxxx
fswebcam -r 1280x720 image2.jpg

• fswebcam -r resolution --no-banner <image_name>

Example: Take an image file with a resolution of 1280x720, no information such as time is displayed on the picture, and save it as image3.jpg

xxxxxxxxxx
fswebcam -r 1280x720 --no-banner image3.jpg

Time-lapse photography

Create a new Webcam folder and enter the file

xxxxxxxxxx
mkdir Webcam

xxxxxxxxxx
cd Webcam

Create a new webcam.sh script file and edit the content

xxxxxxxxxx
sudo nano webcam.sh

File content: The file saving path needs to be modified by yourself. My system username directory is yahboom.

xxxxxxxxxx
#!/bin/bash

DATE=$(date +"%Y-%m-%d_%H%M")

fswebcam -r 1280x720 --no-banner /home/pi/Webcam/$DATE.jpg

Hold down Ctrl+X, enter Y, and press Enter.

Add executable permissions

xxxxxxxxxx
sudo chmod +x webcam.sh

run script

xxxxxxxxxx
./webcam.sh

Using Cron (scheduled tasks)

Open the cron table for editing. You will be prompted to select an editor when using it for the first time. It is recommended to use the nano editor.

xxxxxxxxxx
crontab -e

Add the following code to the edited document: the first 5 * symbols represent a timer of 1 minute, and 2>&1 is to input the error output to the standard output.

xxxxxxxxxx
* * * * * /home/pi/Webcam/webcam.sh 2>&1

After saving the file and exiting, the terminal will output the following content:

xxxxxxxxxx
crontab: installing new crontab

For Cron jobs, you can learn about format and syntax by yourself!

xxxxxxxxxx
If no pictures are generated after one minute, you can restart the service and check whether the path is correct!
Start cron service: sudo service cron start
Stop the cron service: sudo service cron stop

xxxxxxxxxx
If you cannot turn off the camera to automatically shoot using the cron service stop command, it is recommended to use the crontab -e command directly to delete the previously edited content!

Web page preview camera

Use Motion to view the video captured by the USB camera in real time on the web page.

xxxxxxxxxx
CSI cameras cannot use this method to preview the camera!

Install Motion

xxxxxxxxxx
sudo apt install motion

Modify configuration file

-motion.conf

xxxxxxxxxx
sudo nano /etc/motion/motion.conf

Add or modify the following:

xxxxxxxxxx
daemon on
stream_localhost off
picture_output off
movie_output off
stream_maxrate 100
framerate 70
width 640
height 480

illustrate:

1. The above options that are not found in the configuration file can be added directly to the file. For example, the stream_maxrate option needs to be added by yourself, but other options are available.

2. Frame rate: You can modify it yourself (the above parameters are my best results)

3. The nano editor can use the Ctrl+W shortcut keys to search for keywords and quickly locate the content that needs to be modified.

xxxxxxxxxx
stream_maxrate: real-time streaming frame rate
framerate: frame rate
width: image width
height: image height
The above parameters can be adjusted!

• motion

xxxxxxxxxx
sudo nano /etc/default/motion

Add the following code: motion runs in the background

xxxxxxxxxx
start_motion_daemon=yes

Start service

• Start service

xxxxxxxxxx
sudo service motion start

• Out of service

xxxxxxxxxx
sudo service motion stop

• Restart service

xxxxxxxxxx
sudo service motion restart

• Turn on motion

xxxxxxxxxx
sudo motion

Web page preview screen

Enter the start motion service and enable motion commands in the terminal:

xxxxxxxxxx
sudo service motion start
sudo motion

• Preview screen

After turning on motion, enter the car IP: 8081 on the browser on the same LAN to view the real-time image of the camera.

Example: 192.168.2.93:8081