Hi,
Yes, it is possible to calculate the energy and entropy of an image using its histogram. However, it is important to note that the energy and entropy of a histogram are not the same as the energy and entropy of GLCM (Gray-Level Co-occurrence Matrix) features. GLCM features are calculated based on the spatial relationship of pixel pairs in an image, while histogram features are calculated based on the frequency distribution of pixel intensities.
To calculate the energy and entropy of an image using its histogram, you can follow these steps:
- Calculate the normalized histogram of the image. This can be done using the imhist function in MATLAB.
- Calculate the energy of the image as the sum of squared elements in the normalized histogram. This can be done using the sum and .^ functions in MATLAB.
- Calculate the entropy of the image as the negative sum of the product of each element in the normalized histogram and its log-base-2. This can be done using the sum, .*, and log2 functions in MATLAB.
For color images, you can calculate the energy and entropy of each color channel separately, and then average the results to obtain a single value for the entire image.
