MATLAB: How to find total number of pixels in a colour image? How to find the resolution of an 2D image

how to find total number of pixels in a colour image? how to find the resolution of an 2d image?Image Processing Toolboxspatial calibration

How to find total number of pixels in a colour image? How to find the resolution of an 2D image?

[rows, columns, numColorChannels] = size(rgbImage);
numberOfPixels = rows * columns;

Digital resolution is number of rows and columns.

Spatial resolution in the real world units is the field of view in real world units divided by the number of rows or columns.

Perhaps just threshold

binaryImage = volumetricImage3D > someThresholdValue;

image = imread('image.jpg');
[height, width, channels] = size(image);
pixels = height * width