Image resizing enhancement with DCT coefficients

According to the principle of scale transformation, signal expansion in the time domain corresponds to compression in the frequency domain, so that information energy is concentrated in the low frequency part. In this paper, an image enlargement algorithm based on the Discrete Cosine Transform (DCT) is proposed, which preserves the low frequency of the image and combines the corresponding enhancement coefficients to realize the resizing operation in the DCT domain. This paper also reach to proving of the enhancement value determinant. Then comparing the experiment on the scaled image with other interpolation algorithms, the result shows that our algorithm performs better than other methods. This method can also be carried out during DCT transformation, and is easier to implement than other methods.