MaixPy Screen Usage

Introduction

MaixPy provides the display module, which can display images on the screen, and can also send images to MaixVision for display, facilitating debugging and development.

API Documentation

This document introduces commonly used methods. For more APIs, please refer to the display section of the API documentation.

Using the Screen

• Import the display module:

from maix import display

• Create a Display object:

disp = display.Display()

• Display an image:

disp.show(img)

Here, the img object is a maix.image.Image object, which can be obtained through the read method of the camera module, or loaded from an image file in the file system using the load method of the image module, or created as a blank image using the Image class of the image module.

For example:

from maix import image, display

disp = display.Display()
img = image.load("/root/dog.jpg")
disp.show(img)

Here, you need to transfer the dog.jpg file to the /root directory on the device first.

Display text:

from maix import image, display

disp = display.Display()
img = image.Image(320, 240)
img.draw_rectangle(0, 0, disp.width(), disp.height(), color=image.Color.from_rgb(255, 0, 0), thickness=-1)
img.draw_rectangle(10, 10, 100, 100, color=image.Color.from_rgb(255, 0, 0))
img.draw_string(10, 10, "Hello MaixPy!", color=image.Color.from_rgb(255, 255, 255))
disp.show(img)

Read an image from the camera and display it:

from maix import camera, display, app

disp = display.Display()
cam = camera.Camera(320, 240)
while not app.need_exit():
    img = cam.read()
    disp.show(img)

Here, while not app.need_exit(): is used to facilitate exiting the loop when the app.set_exit_flag() method is called elsewhere.

Adjusting Backlight Brightness

You can manually adjust the backlight brightness in the system's "Settings" app. If you want to adjust the backlight brightness programmatically, you can use the set_backlight method, with the parameter being the brightness percentage, ranging from 0 to 100:

disp.set_backlight(50)

Note that when the program exits and returns to the app selection interface, the backlight brightness will automatically revert to the system setting.

Displaying on MaixVision

When running code in MaixVision, images can be displayed on MaixVision for easier debugging and development.

When calling the show method, the image will be automatically compressed and sent to MaixVision for display.

Of course, if you don't have a screen, or to save memory by not initializing the screen, you can also directly call the send_to_maixvision method of the image.Image object to send the image to MaixVision for display.

from maix import image

img = image.Image(320, 240)
img.draw_rectangle(0, 0, img.width(), img.height(), color=image.Color.from_rgb(255, 0, 0), thickness=-1)
img.draw_rectangle(10, 10, 100, 100, color=image.Color.from_rgb(255, 0, 0))
img.draw_string(10, 10, "Hello MaixPy!", color=image.Color.from_rgb(255, 255, 255))
img.send_to_maixvision()