How to draw a PIL image to a DearPyGui canvas?

Question

I would like to draw an image to a canvas in DearPyGui :

import dearpygui.core as dpg

with sdpg.window("Main Window"):
    dpg.set_main_window_size(800, 800)
    dpg.set_main_window_title("Pixel selector")

    dpg.add_drawing('drawing', width=400, height=350)

    img = ImageGrab.grab(bbox=[0, 0, 100, 100])

    # something like this would be great
    dpg.draw_image('drawing', img, [0, 0], [100, 100])

Answer 1

You must convert the image to a 1D list, like so:

import dearpygui.core as dpg
import dearpygui.simple as sdpg
from PIL import ImageGrab


with sdpg.window("Main Window"):
    dpg.set_main_window_size(800, 800)
    dpg.set_main_window_title("Pixel selector")

    dpg.add_drawing('drawing', width=400, height=350)

    img = ImageGrab.grab(bbox=[0, 0, 100, 100])

    dpg_image = []
    for i in range(0, img.height):
        for j in range(0, img.width):
            pixel = img.getpixel((j, i))
            dpg_image.append(pixel[0])
            dpg_image.append(pixel[1])
            dpg_image.append(pixel[2])
            dpg_image.append(255)

    # something like this would be great
    dpg.add_texture("texture id", dpg_image, img.width, img.height)
    dpg.draw_image('drawing', "texture id", [0, 0], [100, 100])

dpg.start_dearpygui()

The list is then added as a texture, which can then be accessed like a regular image file.

Answer 2

I had issues with previous answer since I was loading a PIL Image from disk. After a few hours (annoyed by lack of documentation and examples) I managed to find a solution that works for me and does it faster that using loops:

image = PIL.Image.open("sample.png")

# We need RGBA, in my case loaded image was RGB, so I added alpha channel
image.putalpha(255)

# I had to divide values by 255 since PIL uses 0 to 255 and dearpygui seems 
# to use 0.0 to 1.0
dpg_image = numpy.frombuffer(image.tobytes(), dtype=numpy.uint8) / 255.0

# After this you can use dpg_image with dearpygui and add to texture