The new Raspberry Pi Camera Module 3 offers exceptional image quality, with a choice of standard (75 degree) and wide angle (120 degree) lenses. Best of all, it now has autofocus. Take a picture with Picamera2 is easy, but sometimes you want to press a button to take a photo and be in the picture.
This project uses the Blue Dot Python module and an Android app to create a Bluetooth-controlled camera trigger. Thanks to Blue Dot’s easy-to-use library and Picamera2’s detailed structure, you can capture 1080p photos with a small amount of code.
What you need for this project
- Raspberry Pi 3 or 4
- raspberry pi camera
- Android device
Mounting the Raspberry Pi Camera Module
1. open camera port Gently lift the plastic lock upwards.
2. Insert the ribbon connector with the blue tab facing the USB/Ethernet port. Raspberry Pi Zero users should use an adapter to connect the camera to the port on the right side of the board.
3. close connector lock Gently pull to make sure it is in place.
4. Power on the Raspberry Pi on your desktop. Open Terminal and install the latest Picamera update.
sudo apt update && sudo apt upgrade -yFive. From your device, verify that your camera is working properly. The libcamera command is useful for quickly verifying that your camera is connected and working as expected.
libcamera-helloblue dot installation
The Blue Dot was created by Martin O’Hanlon and provides a really easy way to remotely control a Raspberry Pi. The name “Blue Dot” refers to the large blue dot that dominates the screen of Android devices. Use the Blue Dot as a big blue button to trigger the camera and take a photo.
1. Open the Google Play Store on your Android device and search for Blue Dot. or Please follow this link.
2. Install Blue Dot on your Android device.
3. On the Raspberry Pi, Open a terminal and install the Blue Dot Python library.
sudo pip3 install bluedotFour. Go to the Bluetooth menu, right click and[検出可能にする]Choose.
Five. On your Android device,[設定]>>[接続済みのデバイス]Go to[新しいデバイスのペアリング]Choose.
6. Select “raspberrypi” and follow the pairing instructions. If your Raspberry Pi has a different hostname, you won’t see “raspberrypi”. Look for your host name.
Now that your Android device and Raspberry Pi are connected, let’s create a simple Python script to make sure Blue Dot can communicate between the two devices.
1. open tonyin the main menu under Programming.
2. Create a new file and import the Blue Dot Python library.
from bluedot import BlueDot3. object, bd, Used to operate the library.
sudo pip3 install bluedotFour. Wait until the user presses the blue button. This line of Python is a blocker. Wait for user interaction. When that happens the code moves to the next line.
bd.wait_for_press()Five. Print a message to the Python shell.
print("You pressed the blue dot!")6. Save the code as bd-test.py and[実行]Click. The code waits for a connection from an Android device.
7. On your Android device, open Blue Dot.
8. Choose the hostname of your Raspberry Pi. Usually this is “raspberrypi”.
9. Click a blue dot to trigger Python code to perform an action. A message is displayed in the Python shell.
Full test code listing
from bluedot import BlueDot
bd = BlueDot()
bd.wait_for_press()
print("You pressed the blue dot!")Create a camera trigger with Blue Dot
The goal of this project is to create a camera trigger with Blue Dot. When the button is pressed, a function is started on the Raspberry Pi that handles taking the photo.
1. Create a new file and import the Blue Dot Python library.
from bluedot import BlueDot2. Import Picamera2 and libcamera. The preview class is used to generate a preview window to help frame shots. Autofocus can be used with the new Camera Module 3 using libcamera’s control classes.
from picamera2 import Picamera2, Preview
from libcamera import controls3. Import the pause function from Signals and then the Time library. Pause is used to stop the code from exiting. After the preview window is created, the time delays the code to give it time to frame the shot.
from signal import pause
import timeFour. object, bd, Used to operate the library.
bd = BlueDot()Five. Create an object picam2. This makes using the Picamera2 library easy.
picam2 = Picamera2()6. Define a function take_picture() that will be used to take a picture. A function works by calling its name. This will trigger the function and execute all the steps in it.
7. Create a configuration for the camera to capture still images. This will set the image size to 1080p and the preview window to 720p.
camera_config = picam2.create_still_configuration(main={"size": (1920, 1080)}, lores={"size": (1280, 720)}, display="lores")8. Set Picamera2 to use the new configuration.
picam2.configure(camera_config)9. Start the preview window at 720p resolution. Sets the position using the X and Y coordinates. Otherwise, it defaults to 0,0. Tweak this to suit your needs.
picam2.start_preview(Preview.QTGL, x=100, y=200, width=1280, height=720)Ten. Show preview window.
picam2.start(show_preview=True)11. Set the camera to use continuous autofocus. Note that this only works with Camera Module 3.
picam2.set_controls({"AfMode": controls.AfModeEnum.Continuous})12. Pause for 2 seconds before capturing the image to a file called picam1.jpg.
time.sleep(2)
picam2.capture_file("picam1.jpg")13. Close the preview window and stop Picamera2.
picam2.stop_preview()
picam2.stop()14. Of the functions, Use Blue Dot’s “when_pressed” function to execute the take_picture function to react to user input.
bd.when_pressed = take_picture15. Use pause to prevent the code from terminating.
pause()16. Save the code as bluedot_camera.py and[実行]Click. Start code. You can see that the code is waiting for the Android device to connect.
17. On your Android device, Open a blue dot.
18. Choose the hostname of your Raspberry Pi. Usually this is “raspberrypi”.
19. click the blue dot Trigger the camera. A preview window will appear and after 2 seconds the image will be saved to the micro SD card. Repeated presses will create a new image, but since the filename is the same, it will be overwritten each time.
complete code listing
from bluedot import BlueDot
from picamera2 import Picamera2, Preview
from libcamera import controls
from signal import pause
import time
bd = BlueDot()
picam2 = Picamera2()
def take_picture():
camera_config = picam2.create_still_configuration(main={"size": (1920, 1080)}, lores={"size": (1280, 720)}, display="lores")
picam2.configure(camera_config)
picam2.start_preview(Preview.QTGL, x=100, y=200, width=1280, height=720)
picam2.start(show_preview=True)
picam2.set_controls({"AfMode": controls.AfModeEnum.Continuous})
time.sleep(2)
picam2.capture_file("picam1.jpg")
picam2.stop_preview()
picam2.stop()
bd.when_pressed = take_picture
pause()
