A QGIS field calculator expression with two custom expressions to get the size of images stored as blobs in DB or from links

Get_images_dim.py

from qgis.core import *
from qgis.gui import *
from PyQt5.QtGui import QImage, QImageReader

@qgsfunction(args='auto', group='Custom', referenced_columns=[])
def get_blob_sizes(img_blob, feature, parent):
    """
    Calculate blob image dimension (W x H)
    <h2>Example usage:</h2>
    <ul>
      <li>get_blob_sizes("img_blob") -> '1024 x 512 px'</li>
    </ul>
    """
    
    image = QImage().fromData(img_blob)
    sizeOfImage = image.size()
    img_height = sizeOfImage.height()
    img_width = sizeOfImage.width()
    dim_blob = str(img_width)+ ' x ' + str(img_height) + ' px '
    
    return dim_blob
       
@qgsfunction(args='auto', group='Custom', referenced_columns=[])
def get_image_sizes(img_shape, feature, parent):
    """
    Calculate blob image size
    <h2>Example usage:</h2>
    <ul>
      <li>get_image_sizes(img_shape) -> '1024 x 512 px'</li>
    </ul>
    NEED ABSOLUTE IMAGE LINK
    """
    
    reader = QImageReader(img_shape)
    sizeOfImage = reader.size()
    img_height = sizeOfImage.height()
    img_width = sizeOfImage.width()
    dim_image = str(img_width)+ ' x ' + str(img_height) + ' px '
    
    return dim_image