I used Python to output text and simple graphics to an OLED display connected to a Raspberry Pi.
OLED wiring
i2cdetect -y 1
Luma-OLED Driver
I installed the Luma-OLED driver by following these instructions:
https://luma-oled.readthedocs.io/en/latest/install.html
I installed the driver with this command
$ sudo -H pip3 install --upgrade luma.oled
I enabled I2C communications using the raspi-config application
$ sudo raspi-config
Interface Options | I2C | enable ARM I2C
i2c permissions
I followed the steps described by Alexander Rüedlinger to allow non-root users to access i2c devices (specifically the OLED display).
1) Create new user group called i2c:
$ sudo groupadd i2c
2) Change the group ownership of /dev/i2c-1 to i2c:
$ sudo chown :i2c /dev/i2c-1
3) Change the file permissions of the device /dev/i2c-1 so users of the i2c group can read and write to the device:
$ sudo chmod g+rw /dev/i2c-1
4) Add your user to the group i2c:
$ sudo usermod -aG i2c <username>
Python code
The hello.py code running on configured hardware
Displaying an image on the OLED display
I downloaded a stop sign image and updated the hello.py code to display the image on the OLED display.
Stop sign
Using OpenCV and luma.oled to display video on the OLED display
I used the cv2 library (OpenCV) to read frames from a dog video I downloaded from:
https://pixabay.com/videos/puppy-dog-playful-beach-sand-play-4740/
I then updated the code to send images captured by the webcam to the OLED display.
Dog video
Webcam
hello.py
PYTHON
1from luma.core.interface.serial import i2c, spi, pcf8574 2from luma.core.interface.parallel import bitbang_6800 3from luma.core.render import canvas 4from luma.oled.device import ssd1306, ssd1309, ssd1325, ssd1331, sh1106, sh1107, ws0010 5from time import sleep 6 7# rev.1 users set port=0 8# substitute spi(device=0, port=0) below if using that interface 9# substitute bitbang_6800(RS=7, E=8, PINS=[25,24,23,27]) below if using that interface 10serial = i2c(port=1, address=0x3C) 11 12# substitute ssd1331(...) or sh1106(...) below if using that device 13device = sh1106(serial) 14 15with canvas(device) as draw: 16 draw.rectangle(device.bounding_box, outline="white", fill="black") 17 draw.text((30, 40), "Hello World", fill="white") 18 19sleep(10)
stop_sign_display.py
PYTHON
1from luma.core.interface.serial import i2c, spi, pcf8574 2from luma.core.interface.parallel import bitbang_6800 3from luma.core.render import canvas 4from luma.oled.device import ssd1306, ssd1309, ssd1325, ssd1331, sh1106, sh1107 5from time import sleep 6 7from PIL import Image 8 9serial = i2c(port=1, address=0x3C) 10device = sh1106(serial) 11 12width = device.width 13height = device.height 14 15image = Image.open("stop.png") 16 17image_r = image.resize((width,height), Image.LANCZOS) 18# Image.BICUBIC is another option 19image_bw = image_r.convert("1") 20 21device.display(image_bw) 22 23sleep(10)
dog_display_window_and_oled.py
PYTHON
1from luma.core.interface.serial import i2c, spi, pcf8574 2from luma.core.interface.parallel import bitbang_6800 3from luma.core.render import canvas 4from luma.oled.device import ssd1306, ssd1309, ssd1325, ssd1331, sh1106, sh1107 5 6from time import sleep 7 8import cv2 9 10# OpenCV follows BGR color convention and PIL follows RGB color convention 11 12# Python Imaging Library 13from PIL import Image 14 15serial = i2c(port=1, address=0x3C) 16device = sh1106(serial) 17 18width = device.width 19height = device.height 20 21cap = cv2.VideoCapture("dog.mp4") 22while True: 23 ret, frame = cap.read() 24 if not ret: 25 break 26 cv2.imshow("Img", frame) 27 28 color_coverted = cv2.cvtColor(frame, cv2.COLOR_BGR2RGB) 29 pil_image = Image.fromarray(color_coverted) 30 image_r = pil_image.resize((width,height), Image.LANCZOS) 31 # Image.BICUBIC is another option 32 image_bw = image_r.convert("1") 33 34 device.display(image_bw) 35 36 key = cv2.waitKey(1) 37 if key == 27: 38 break 39 40cap.release() 41cv2.destroyAllWindows()
webcam_display_window_and_oled.py
PYTHON
1... 2cap = cv2.VideoCapture(0) 3...