I am trying to understand how the Discrete Cosine Transformation works but I am not sure if I am at the right road.
Assuming that I have an $8\times8$ pixels image and I am applying the DCT to this sample. What I will get as a result is a $8\times8$ matrix of the DCT Coefficients.
In order to convert from this to the original image I will need to multiply each DCT Coefficient with its corresponding basis function and sum the result. But how do I calculate the basis function if DCT only returns the coefficients?